U.S. patent application number 14/615418 was filed with the patent office on 2015-06-04 for novel oxazine derivatives and their use in the treatment of disease.
This patent application is currently assigned to NOVARTIS AG. The applicant listed for this patent is Rainer Martin LUEOEND, Rainer MACHAUER, Heinrich RUEEGER, Siem Jacob VEENSTRA. Invention is credited to Rainer Martin LUEOEND, Rainer MACHAUER, Heinrich RUEEGER, Siem Jacob VEENSTRA.
Application Number | 20150150877 14/615418 |
Document ID | / |
Family ID | 47018309 |
Filed Date | 2015-06-04 |
United States Patent
Application |
20150150877 |
Kind Code |
A1 |
LUEOEND; Rainer Martin ; et
al. |
June 4, 2015 |
NOVEL OXAZINE DERIVATIVES AND THEIR USE IN THE TREATMENT OF
DISEASE
Abstract
The invention relates to novel oxazine derivatives of formula
(I), and pharmaceutically acceptable salts thereof, ##STR00001## in
which all of the variables are as defined in the specification,
pharmaceutical compositions thereof, combinations thereof, and
their use as medicaments, particularly for the treatment of
Alzheimer's Disease or diabetes via inhibition of BACE-1 or
BACE-2.
Inventors: |
LUEOEND; Rainer Martin;
(Therwil, CH) ; MACHAUER; Rainer; (Freiburg,
CH) ; RUEEGER; Heinrich; (Flueh, CH) ;
VEENSTRA; Siem Jacob; (Lorrach, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LUEOEND; Rainer Martin
MACHAUER; Rainer
RUEEGER; Heinrich
VEENSTRA; Siem Jacob |
Therwil
Freiburg
Flueh
Lorrach |
|
CH
CH
CH
DE |
|
|
Assignee: |
NOVARTIS AG
Basel
CH
|
Family ID: |
47018309 |
Appl. No.: |
14/615418 |
Filed: |
February 5, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13592580 |
Aug 23, 2012 |
|
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14615418 |
|
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61665395 |
Jun 28, 2012 |
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61527172 |
Aug 25, 2011 |
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Current U.S.
Class: |
514/228.8 |
Current CPC
Class: |
C07D 413/14 20130101;
A61P 25/28 20180101; A61K 31/5355 20130101; A61P 3/00 20180101;
A61P 5/50 20180101; A61P 9/12 20180101; A61P 3/04 20180101; A61P
43/00 20180101; A61K 45/06 20130101; A61P 25/00 20180101; A61P 3/10
20180101 |
International
Class: |
A61K 31/5355 20060101
A61K031/5355 |
Claims
1. A method of treating Alzheimer's Disease or mild cognitive
impairment comprising, administering to a patient in need thereof,
a compound of formula (I), or a pharmaceutically acceptable salt
thereof, ##STR00062## wherein R.sup.1 and R.sup.2 are independently
hydrogen or halogen; R.sup.3 and R.sup.4 are independently hydrogen
or C.sub.1-3alkyl; or R.sup.3 and R.sup.4 taken together are
cyclopropyl; or R.sup.1 and R.sup.4 are hydrogen and R.sup.2 and
R.sup.3 taken together are --CH.sub.2--O--CH.sub.2--; R.sup.5 is
C.sub.1-3alkyl, halogen-C.sub.1-3alkyl or
C.sub.1-3alkoxy-C.sub.1-3alkyl; and R.sup.6 is phenyl or a 5- or
6-membered monocyclic heteroaryl comprising 1, 2, 3 or 4
heteroatoms independently selected from N, O and S, and wherein
said phenyl or heteroaryl is optionally substituted by 1, 2, 3 or 4
substituents independently selected from halogen, cyano, amino,
hydroxy, C.sub.1-4alkyl, halogen-C.sub.1-4alkyl,
halogen-C.sub.1-4alkylthio, halogen-C.sub.1-4alkoxy,
C.sub.1-4alkoxy, C.sub.1-4alkoxy-C.sub.1-4alkyl,
C.sub.1-4alkoxy-C.sub.1-4alkoxy,
C.sub.1-4alkoxy-C.sub.1-4alkylthio,
C.sub.1-4alkoxy-C.sub.2-4alkenyl, C.sub.1-4alkoxy-C.sub.2-4alkynyl,
hydroxy-C.sub.1-4alkyl, hydroxy-C.sub.2-4alkenyl and
hydroxy-C.sub.2-4alkynyl.
2. The method according to claim 1, or a pharmaceutically
acceptable salt thereof, wherein R.sup.1 and R.sup.2 are both
fluoro.
3. The method according to claim 1, or a pharmaceutically
acceptable salt thereof, wherein R.sup.3 and R.sup.4 are both
hydrogen.
4. The method according to claim 1, or a pharmaceutically
acceptable salt thereof, wherein R.sup.5 is methyl.
5. The method according to claim 1, or a pharmaceutically
acceptable salt thereof, wherein R.sup.6 is a 6-membered monocyclic
heteroaryl comprising 1, 2, 3 or 4 heteroatoms independently
selected from N, O and S, and wherein said phenyl or heteroaryl is
optionally substituted by 1, 2, 3 or 4 substituents independently
selected from halogen, cyano, amino, hydroxy, C.sub.1-4alkyl,
halogen-C.sub.1-4alkyl, halogen-C.sub.1-4alkylthio,
halogen-C.sub.1-4alkoxy, C.sub.1-4alkoxy,
C.sub.1-4alkoxy-C.sub.1-4alkyl, C.sub.1-4alkoxy-C.sub.1-4alkoxy and
C.sub.1-4alkoxy-C.sub.1-4alkylthio.
6. The method according to claim 1, or a pharmaceutically
acceptable salt thereof, wherein R.sup.6 is a pyridin-2-yl group
which is substituted by 2 substituents and wherein one of the
substituents is located at the para position and one of the
substituents is located at the ortho position of the pyridin-2-yl
group relative to the amide linker and wherein the substituents are
independently selected from halogen, cyano, amino, hydroxy, methyl,
trifluoromethyl, methoxy and trifluoromethoxy.
7. The method according to claim 1 which is selected from:
5-Cyano-3-methyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; 3-Chloro-5-cyano-pyridine-2-carboxylic
acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; 3-Chloro-5-cyano-pyridine-2-carboxylic
acid
[6-((R)-2-amino-5,5-difluoro-4,6,6-trimethyl-5,6-dihydro-4H-[1,3]oxazin-4-
-yl)-5-fluoro-pyridin-2-yl]-amide;
5-Cyano-3-methyl-pyridine-2-carboxylic acid
{6-[(R)-2-amino-5,5-difluoro-4-(2-methoxy-ethyl)-5,6-dihydro-4H-[1,3-
]oxazin-4-yl]-5-fluoro-pyridin-2-yl}-amide;
3-Chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
{6-[(R)-2-amino-5,5-difluoro-4-(2-methoxy-ethyl)-5,6-dihydro-4H-[1,3]oxaz-
in-4-yl]-5-fluoro-pyridin-2-yl}-amide;
3-Chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Amino-5-trifluoromethyl-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; 3,5-Dichloro-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Amino-5-(2,2,2-trifluoro-ethoxy)pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Amino-5-(2,2-difluoro-ethoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Amino-5-(3-fluoro-propoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
5-Methoxy-3-methyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Amino-5-(3-methoxy-prop-1-ynyl)-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Amino-5-fluoromethoxy-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-y-
l)-5-fluoro-pyridin-2-yl]amide;
3-Amino-5-(2-methoxy-ethoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Amino-5-(3-hydroxy-prop-1-ynyl)-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; 3-Amino-5-fluoro-pyridine-2-carboxylic
acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; 3-Amino-5-chloro-pyridine-2-carboxylic
acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; 3-Chloro-pyridine-2-carboxylic
acid[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl-
)-5-fluoro-pyridin-2-yl]amide;
3-Chloro-5-(3-methoxy-prop-1-ynyl)pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Amino-5-difluoromethyl-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-y-
l)-5-fluoro-pyridin-2-yl]-amide;
3-Amino-5-(2-chloro-ethoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Chloro-5-(2,2-difluoro-ethoxy)-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Amino-5-(2-fluoro-ethoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Chloro-5-fluoromethoxy-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-y-
l)-5-fluoro-pyridin-2-yl]-amide;
3-Chloro-5-ethoxy-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-y-
l)-5-fluoro-pyridin-2-yl]-amide;
3-Amino-5-(penta-deutero-ethoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Amino-5-(2-methoxy-ethyl)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
4-Chloro-1-difluoromethyl-1H-pyrazole-3-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; 3-Amino-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Chloro-5-(3-hydroxy-prop-1-ynyl)-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Amino-5-difluoromethyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-y-
l)-5-fluoro-pyridin-2-yl]amide;
3-Amino-6-chloro-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; 5-Cyano-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide;
3-Chloro-5-(1,1-difluoro-ethyl)-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; and
3-Amino-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; and pharmaceutically acceptable salts
thereof.
8. A method of treating Alzheimer's Disease or mild cognitive
impairment comprising, administering to a patient in need thereof,
##STR00063## or a salt thereof.
9. A method of treating Alzheimer's Disease or mild cognitive
impairment comprising, administering to a patient in need thereof,
##STR00064## or a salt thereof.
10. A combination comprising a therapeutically effective amount of
a compound, or a pharmaceutically acceptable salt thereof, of
formula (I), ##STR00065## wherein R.sup.1 and R.sup.2 are
independently hydrogen or halogen; R.sup.3 and R.sup.4 are
independently hydrogen or C.sub.1-3alkyl; or R.sup.3 and R.sup.4
taken together are cyclopropyl; or R.sup.1 and R.sup.4 are hydrogen
and R.sup.2 and R.sup.3 taken together are
--CH.sub.2--O--CH.sub.2--; R.sup.5 is C.sub.1-3alkyl,
halogen-C.sub.1-3alkyl or C.sub.1-3alkoxy-C.sub.1-3alkyl; and
R.sup.6 is phenyl or a 5- or 6-membered monocyclic heteroaryl
comprising 1, 2, 3 or 4 heteroatoms independently selected from N,
O and S, and wherein said phenyl or heteroaryl is optionally
substituted by 1, 2, 3 or 4 substituents independently selected
from halogen, cyano, amino, hydroxy, C.sub.1-4alkyl,
halogen-C.sub.1-4alkyl, halogen-C.sub.1-4alkylthio,
halogen-C.sub.1-4alkoxy, C.sub.1-4alkoxy,
C.sub.1-4alkoxy-C.sub.1-4alkyl, C.sub.1-4alkoxy-C.sub.1-4alkoxy,
C.sub.1-4alkoxy-C.sub.1-4alkylthio,
C.sub.1-4alkoxy-C.sub.2-4alkenyl, C.sub.1-4alkoxy-C.sub.2-4alkynyl,
hydroxy-C.sub.1-4alkyl, hydroxy-C.sub.2-4alkenyl and
hydroxy-C.sub.2-4alkynyl, and a second drug substance, for
simultaneous or sequential administration.
Description
FIELD OF THE INVENTION
[0001] The invention relates to novel oxazine derivatives and
pharmaceutically acceptable salts thereof, pharmaceutical
compositions thereof, pharmaceutical combinations thereof, and
their use as medicaments, particularly for the treatment of
neurodegeneration via inhibition of BACE-1 or diabetes via
inhibition of BACE-2.
BACKGROUND OF THE INVENTION
[0002] Alzheimer's Disease is a devastating neurodegenerative
disorder. Its sporadic forms affect an elderly population (sharp
increase in incidence at >75 years of age), in addition, there
are various familial forms with an onset of the disease in the
fourth or fifth decade of life. Pathologically, it is characterized
by the presence of extracellular senile plaques, and intracellular
neurofibrillar tangles in patient's brains. The core constituent of
the senile plaques are small, 4 kDa amyloid peptides. They are
generated by the proteolytic processing of a large transmembrane
protein, amyloid precursor protein (APP). Cleavage of APP by
beta-secretase (BACE-1) releases the soluble APP-beta fragment,
while the 99-amino acid long C-terminus remains tethered to the
membrane. This C-terminal fragment is subsequently proteolytically
processed by gamma-secretase (an membrane multi-enzyme complex) to
generate amyloid peptides of various length, predominantly 40 and
42 amino acids long (Hardy J, Selkoe D J (2002) Science; 297
(5580):353-356).
[0003] If, under pathologic conditions, the generation of these
peptides occurs at an increased rate, or if their removal from the
brain is disturbed, increased brain amyloid peptide concentrations
leads to the formation of oligomers, fibrils and eventually plaques
(Farris W, et al (2007) Am. J. Pathol.; 171 (1):241-251). It has
been shown, that deposition of amyloid peptides and plaques in the
brain is the first measurable event in the pathogenesis of
Alzheimers Disease, and that it is the trigger for loss of
synapses, synaptic contacts, and neurons (Grimmer T, et al (2009)
Neurobiology of Aging; 30 (12):1902-1909). Brain atrophy caused by
massive neuron loss is followed by impairments in cognition,
memory, orientation and the ability to perform the tasks of daily
living, i.e. clinically manifest dementia (Okello A, et al (2009)
Neurology; 73 (10):754-760).
[0004] BACE-1, also known as Asp2 or Memapsin 2, is a transmembrane
aspartic protease highly expressed in neurons. It co-localizes with
its substrate APP in Golgi and endocytic compartments (Willem M,
Lammich S, Haass C (2009) Semin. Cell Dev. Biol; 20 (2):175-182).
Knock-out studies in mice have demonstrated the absence of amyloid
peptide formation, while the animals are healthy and fertile (Ohno
M, et al (2007) Neurobiol. Dis.; 26 (1):134-145). Genetic ablation
of BACE-1 in APP-overexpressing mice has demonstrated absence of
plaque formation, and the reverse of cognitive deficits (Ohno M, et
al (2004) Neuron; 41 (1):27-33). BACE-1 levels are elevated in the
brains of sporadic Alzheimer's Disease patients (Hampel H, Shen Y
(2009) Scand. J. Clin. Lab. Invest.; 69 (1):8-12).
[0005] Taken together, these findings suggest that the inhibition
of BACE-1 may be a favourable therapeutic strategy for the
treatment of Alzheimer's Disease.
[0006] Beta-site amyloid precursor protein cleaving enzyme 2
(BACE-2) is a transmembrane aspartic protease that is highly
expressed in pancreatic .beta. cells and other peripheral tissues
(Brian D. Bennett, Safura Babu-Khan, Richard Loeloff, Jean-Claude
Louis, Eileen Curran; Martin Citron, and Robert Vassar (2000) J J.
Biol. Chem. 275(27) 20647-20651). BACE-2 is closely related to
BACE-1 or beta secretase. However, despite structural and sequence
similarities the substrate specificity of BACE-1 and BACE-2 appear
to be different. While A.beta. or .beta.-amyloid peptide is the
main substrate of BACE-1, BACE-2 does not generate either form of
A.beta. (Vassar, R., Bennett, B. D., Babu-Khan, S., Kahn, S.,
Mendiaz, E. A., Denis, P., Teplow, D. B., Ross, S., Amarante, P.,
Loeloff, R., Luo, Y., Fisher, S., Fuller, J., Edenson, S., Lile,
J., Jarosinski, M. A., Biere, A. L., Curran, E., Burgess, T.,
Louis, J.-C., Collins, F., Treanor, J., Rogers, G., and Citron, M.
(1999) Science 286, 735-741).
[0007] Transmembrane protein 27 (TMEM27 or collectrin) plays an
important role in .beta.-cell proliferation and insulin secretion
(Pinar Akpinar, Satoru Kuwajima, Jan Krutzfeldt, and Markus Stoffel
(2005) Tmem27: Cell Metabolism. 2(6) 385-397) and has been
identified as a substrate for BACE-2 (WO 2010/063718). Tmem27
exists as a dimer and the extracellular domain is cleaved and shed
from the plasma in a .beta. cell-specific manner. Overexpression of
full-length Tmem27, but not the truncated or soluble protein,
increases .beta. cell proliferation, suggesting that the full
length protein is required for this biological function. Tcf1
(hepatocyte nuclear factor-1.alpha., HNF-1.alpha.) controls the
transcription of TMEM27. Mice with targeted deletion of Tcf1
exhibit decreased .beta. cell mass, and knockdown of Tmem27 using
RNAi results in a reduction of cell proliferation. Transgenic mice
with increased expression of Tmem27 in pancreatic .beta. cells
exhibit increased .beta. cell mass compared to their wild-type
littermates. This data indicates that TMEM27 plays a role in
control of .beta. cell mass and that inhibition of BACE-2 which
cleaves TMEM27 could be useful for treating loss of .beta. cell
mass and function, the underlying cause of diabetes.
[0008] Taken together, these findings suggest that the inhibition
of BACE-2 may be a favourable therapeutic strategy for the
treatment and prevention of metabolic disorders related to
decreased .beta. cell mass and/or function, such as type 2
diabetes.
[0009] Oxazine derivatives having BACE-1 and/or BACE-2 activity are
described in the literature, for example WO 2011/069934 A1.
However, there is an ongoing requirement for further structurally
diverse BACE inhibitors which may have improved properties in terms
of their inhibitory activity, selectivity, solubility, metabolism,
pharmacokinetics and/or safety profile. It may also be advantageous
to identify compounds which show selective inhibitory activity for
BACE-1 over BACE-2 or BACE-2 over BACE-1.
SUMMARY OF THE INVENTION
[0010] The present invention therefore relates to novel oxazine
derivatives having BACE inhibitory activity, to their preparation,
to their medical use and to medicaments comprising them.
[0011] More particularly, in a first aspect the invention relates
to a compound of the formula (I), or a pharmaceutically acceptable
salt thereof:
##STR00002##
wherein R.sup.1 and R.sup.2 are independently hydrogen or halogen;
R.sup.3 and R.sup.4 are independently hydrogen or C.sub.1-3alkyl;
or R.sup.3 and R.sup.4 taken together are cyclopropyl; or R.sup.1
and R.sup.4 are hydrogen and R.sup.2 and R.sup.3 taken together are
--CH.sub.2--O--CH.sub.2--; R.sup.5 is C.sub.1-3alkyl,
halogen-C.sub.1-3alkyl or C.sub.1-3alkoxy-C.sub.1-3alkyl; and
R.sup.6 is phenyl or a 5- or 6-membered monocyclic heteroaryl
comprising 1, 2, 3 or 4 heteroatoms independently selected from N,
O and S, and wherein said phenyl or heteroaryl is optionally
substituted by 1, 2, 3 or 4 substituents independently selected
from halogen, cyano, amino, hydroxy, C.sub.1-4alkyl,
halogen-C.sub.1-4alkyl, halogen-C.sub.1-4alkylthio,
halogen-C.sub.1-4alkoxy, C.sub.1-4alkoxy,
C.sub.1-4alkoxy-C.sub.1-4alkyl, C.sub.1-4alkoxy-C.sub.1-4alkoxy,
C.sub.1-4alkoxy-C.sub.1-4alkylthio,
C.sub.1-4alkoxy-C.sub.2-4alkenyl, C.sub.1-4alkoxy-C.sub.2-4alkynyl,
hydroxy-C.sub.1-4alkyl, hydroxy-C.sub.2-4alkenyl and
hydroxy-C.sub.2-4alkynyl.
[0012] More particularly, in a second aspect the invention relates
to a compound of the formula (I), or a pharmaceutically acceptable
salt thereof:
##STR00003##
wherein R.sup.1 and R.sup.2 are independently hydrogen or halogen;
R.sup.3 and R.sup.4 are independently hydrogen or C.sub.1-3alkyl;
or R.sup.3 and R.sup.4 taken together are cyclopropyl; R.sup.5 is
C.sub.1-3alkyl, halogen-C.sub.1-3alkyl or
C.sub.1-3alkoxy-C.sub.1-3alkyl; and R.sup.6 is phenyl or a 5- or
6-membered monocyclic heteroaryl comprising 1, 2, 3 or 4
heteroatoms independently selected from N, O and S, and wherein
said phenyl or heteroaryl is optionally substituted by 1, 2, 3 or 4
substituents independently selected from halogen, cyano, amino,
hydroxy, C.sub.1-4alkyl, halogen-C.sub.1-4alkyl,
halogen-C.sub.1-4alkylthio, halogen-C.sub.1-4alkoxy,
C.sub.1-4alkoxy, C.sub.1-4alkoxy-C.sub.1-4alkyl,
C.sub.1-4alkoxy-C.sub.1-4alkoxy,
C.sub.1-4alkoxy-C.sub.1-4alkylthio,
C.sub.1-4alkoxy-C.sub.2-4alkenyl, C.sub.1-4alkoxy-C.sub.2-4alkynyl,
hydroxy-C.sub.1-4alkyl, hydroxy-C.sub.2-4alkenyl and
hydroxy-C.sub.2-4alkynyl.
[0013] More particularly, in a third aspect the invention relates
to a compound of the formula (I), or a pharmaceutically acceptable
salt thereof:
##STR00004##
wherein R.sup.1 and R.sup.2 are independently hydrogen or halogen;
R.sup.3 and R.sup.4 are independently hydrogen or C.sub.1-3alkyl;
or R.sup.3 and R.sup.4 taken together are cyclopropyl; R.sup.5 is
C.sub.1-3alkyl, halogen-C.sub.1-3alkyl or
C.sub.1-3alkoxy-C.sub.1-3alkyl; and R.sup.6 is phenyl or a 5- or
6-membered monocyclic heteroaryl comprising 1, 2, 3 or 4
heteroatoms independently selected from N, O and S, and wherein
said phenyl or heteroaryl is optionally substituted by 1, 2, 3 or 4
substituents independently selected from halogen, cyano, amino,
hydroxy, C.sub.1-4alkyl, halogen-C.sub.1-4alkyl,
halogen-C.sub.1-4alkylthio, halogen-C.sub.1-4alkoxy,
C.sub.1-4alkoxy, C.sub.1-4alkoxy-C.sub.1-4alkyl,
C.sub.1-4alkoxy-C.sub.1-4alkoxy and
C.sub.1-4alkoxy-C.sub.1-4alkylthio.
DEFINITIONS
[0014] As used herein, the term "C.sub.1-4alkyl" refers to a
straight or branched hydrocarbon chain radical consisting solely of
carbon and hydrogen atoms, containing no unsaturation, having from
one to four carbon atoms, and which is attached to the rest of the
molecule by a single bond. Examples of C.sub.1-4alkyl include
methyl, (R)-methyl, ethyl, n-propyl, 1-methylethyl (iso-propyl)
n-butyl and 1,1-dimethylethyl (t-butyl). The term "C.sub.1-3alkyl"
refers to alkyl radicals as defined herein having from one to three
carbon atoms.
[0015] As used herein, the term "C.sub.2-4alkenyl" refers to a
straight or branched hydrocarbon chain radical group consisting
solely of carbon and hydrogen atoms, containing at least one double
bond, having from two to four carbon atoms, and which is attached
to the rest of the molecule by a single bond. Examples of
C.sub.2-6alkenyl include, ethenyl, prop-1-enyl and but-1-enyl.
[0016] As used herein, the term "C.sub.2-4alkynyl" refers to a
straight or branched hydrocarbon chain radical group consisting
solely of carbon and hydrogen atoms, containing at least one triple
bond, having from two to four carbon atoms, and which is attached
to the rest of the molecule by a single bond. Examples of
C.sub.2-4alkynyl include ethynyl, prop-1-ynyl and but-1-ynyl.
[0017] As used herein, the term "C.sub.1-4alkoxy" refers to a
radical of the formula --O--R.sub.a where R.sub.a is a
C.sub.1-4alkyl radical as defined above. Examples of
C.sub.1-4alkoxy include methoxy, ethoxy, propoxy, isopropoxy,
butoxy and isobutoxy. The term "C.sub.1-3alkoxy" is to be construed
accordingly.
[0018] As used herein, the term "C.sub.1-4alkoxy-C.sub.1-4alkyl"
refers to a radical of the formula --R.sub.a--O--R.sub.a where each
R.sub.a is independently a C.sub.1-4alkyl radical as defined above.
The oxygen atom may be bonded to any carbon atom in either alkyl
radical. Examples of C.sub.1-4alkoxy-C.sub.1-4alkyl include
methoxy-methyl, methoxy-ethyl, ethoxy-ethyl, 1-ethoxy-propyl and
2-methoxy-butyl. The term "C.sub.1-3alkoxy-C.sub.1-3alkyl" is to be
construed accordingly.
[0019] As used herein, the term "C.sub.1-4alkoxy-C.sub.1-4alkoxy"
refers to a radical of the formula --O--R.sub.a--O--R.sub.a where
each R.sub.a is independently a C.sub.1-4alkyl radical as defined
above. The oxygen atoms may be bonded to any alkyl radical carbon
atom. Examples of C.sub.1-4alkoxy-C.sub.1-4alkoxy include
methoxy-methoxy, methoxy-ethoxy, ethoxy-ethoxy, 1-ethoxy-propyloxy
and 2-methoxy-butoxy.
[0020] As used herein, the term
"C.sub.1-4alkoxy-C.sub.1-4alkylthio" refers to a radical of the
formula --S--R.sub.a--O--R.sub.a where each R.sub.a is
independently a C.sub.1-4alkyl radical as defined above. The oxygen
and sulfur atoms may be bonded to any alkyl radical carbon atom.
Examples of C.sub.1-4alkoxy-C.sub.1-4alkylthio include
methoxy-methylthio, methoxy-ethylthio, ethoxy-ethylthio,
1-ethoxy-propylthio and 2-methoxy-butylthio.
[0021] As used herein, the term "C.sub.1-4alkoxy-C.sub.2-4alkenyl"
refers to a radical of the formula --R.sub.b--O--R.sub.a where
R.sub.a is a C.sub.1-4alkyl radical as defined above and R.sub.b is
a C.sub.2-4alkenyl radical as defined above. The oxygen atom may be
bonded to any carbon atom in the alkyl radical and any carbon atom
in the alkenyl radical. Examples of
C.sub.1-4alkoxy-C.sub.2-4alkenyl include methoxy-ethenyl,
ethoxy-ethenyl, 3-methoxy-propenyl, 1-ethoxy-propenyl and
2-methoxy-butenyl.
[0022] As used herein, the term "C.sub.1-4alkoxy-C.sub.2-4alkynyl"
refers to a radical of the formula --R.sub.b--O--R.sub.a where
R.sub.a is a C.sub.1-4alkyl radical as defined above and R.sub.b is
a C.sub.2-4alkynyl radical as defined above. The oxygen atom may be
bonded to any carbon atom in the alkyl radical and any available
carbon atom in the alkynyl radical. Examples of
C.sub.1-4alkoxy-C.sub.2-4alkynyl include methoxy-ethynyl,
ethoxy-ethynyl, 3-methoxy-propynyl, 1-ethoxy-propynyl and
2-methoxy-butynyl.
[0023] The term "halogen" refers to bromo, chloro, fluoro or
iodo.
[0024] As used herein, the term "halogen-C.sub.1-4alkyl" refers to
a C.sub.1-4alkyl radical, as defined above, substituted by one or
more halo radicals, as defined above. Examples of
halogen-C.sub.1-4alkyl include trifluoromethyl, difluoromethyl,
fluoromethyl, trichloromethyl, 2,2,2-trifluoroethyl,
1-fluoromethyl-2-fluoroethyl, 3-bromo-2-fluoropropyl and
1-bromomethyl-2-bromoethyl. The term "halogen-C.sub.1-3alkyl" is to
be construed accordingly.
[0025] As used herein, the term "halogen-C.sub.1-4alkylthio" refers
to a radical of the formula --S--R.sub.a where R.sub.a is a
halogen-C.sub.1-4alkyl radical as defined above. Examples of
halogen-C.sub.1-4alkylthio include trifluoromethylthio,
difluoromethylthio, fluoromethylthio, trichloromethylthio,
2,2,2-trifluoroethylthio, 1-fluoromethyl-2-fluoroethylthio,
3-bromo-2-fluoropropylthio and 1-bromomethyl-2-bromoethylthio.
[0026] As used herein, the term "halogen-C.sub.1-4alkoxy" refers to
a C.sub.1-4alkoxy radical, as defined above, substituted by one or
more halo radicals, as defined above. Examples of
halogen-C.sub.1-4alkoxy include trifluoromethoxy, difluoromethoxy,
fluoromethoxy, trichloromethoxy, 2,2,2-trifluoroethoxy,
1-fluoromethyl-2-fluoroethoxy, 3-bromo-2-fluoropropoxy and
1-bromomethyl-2-bromoethoxy.
[0027] As used herein, the term "heteroaryl" refers to a 5- or
6-membered aromatic monocyclic ring radical which comprises 1, 2, 3
or 4 heteroatoms individually selected from nitrogen, oxygen and
sulfur. The heteroaryl radical may be bonded via a carbon atom or
heteroatom. Examples of heteroaryl include furyl, pyrrolyl,
thienyl, pyrazolyl, imidazolyl, thiazolyl, isothiazolyl, oxazolyl,
isoxazolyl, triazolyl, tetrazolyl, pyrazinyl, pyridazinyl,
pyrimidyl and pyridyl.
[0028] As used herein, the term "hydroxyC.sub.1-4alkyl" refers to a
C.sub.1-4alkyl radical as defined above, wherein one of the
hydrogen atoms of the C.sub.1-4alkyl radical is replaced by OH.
Examples of hydroxyC.sub.1-4alkyl include hydroxy-methyl,
2-hydroxy-ethyl, 2-hydroxy-propyl, 3-hydroxy-propyl and
2-hydroxy-butyl.
[0029] As used herein, the term "hydroxyC.sub.2-4alkenyl" refers to
a C.sub.2-4alkenyl radical as defined above, wherein one of the
hydrogen atoms of the C.sub.2-4alkenyl radical is replaced by OH.
Examples of hydroxyC.sub.1-4alkenyl include 2-hydroxy-ethenyl,
2-hydroxy-propenyl, 3-hydroxy-propenyl and 2-hydroxy-butenyl.
[0030] As used herein, the term "hydroxyC.sub.2-4alkynyl" refers to
a C.sub.2-4alkynyl radical as defined above, wherein one of the
hydrogen atoms of the C.sub.2-4alkynyl radical is replaced by OH.
Examples of hydroxyC.sub.1-4alkynyl include 2-hydroxy-ethynyl,
3-hydroxy-propynyl and 2-hydroxy-butynyl.
[0031] As used herein, the term "a," "an," "the" and similar terms
used in the context of the present invention (especially in the
context of the claims) are to be construed to cover both the
singular and plural unless otherwise indicated herein or clearly
contradicted by the context. The use of any and all examples, or
exemplary language (e.g. "such as") provided herein is intended
merely to better illuminate the invention and does not pose a
limitation on the scope of the invention otherwise claimed.
[0032] The term "compounds of the present invention" (unless
specifically identified otherwise) refers to compounds of formula
(I), (Ia), (Ib) or (Ic), compounds of the Examples,
pharmaceutically acceptable salts of such compounds, and/or
hydrates or solvates of such compounds, as well as, all
stereoisomers (including diastereoisomers and enantiomers),
tautomers and isotopically labeled compounds (including deuterium).
The term "agents of the invention" is intended to have the same
meaning as "compounds of the present invention".
[0033] As used herein, the term "inhibit", "inhibition" or
"inhibiting" refers to the reduction or suppression of a given
condition, symptom, or disorder, or disease, or a significant
decrease in the baseline activity of a biological activity or
process.
[0034] As used herein, the term "pharmaceutically acceptable
carrier" includes any and all solvents, dispersion media, coatings,
surfactants, antioxidants, preservatives (e.g., antibacterial
agents, antifungal agents), isotonic agents, absorption delaying
agents, salts, preservatives, drugs, drug stabilizers, binders,
excipients, disintegration agents, lubricants, sweetening agents,
flavoring agents, dyes, and the like and combinations thereof, as
would be known to those skilled in the art (see, for example,
Remington's Pharmaceutical Sciences, 18th Ed. Mack Printing
Company, 1990, pp. 1289-1329). Except insofar as any conventional
carrier is incompatible with the active ingredient, its use in the
therapeutic or pharmaceutical compositions is contemplated.
[0035] As used herein, the term "prevention" of any particular
disease or disorder refers to the administration of a compound of
the invention to a subject before any symptoms of that disease or
disorder are apparent.
[0036] As used herein, the term "subject" refers to an animal.
Typically the animal is a mammal. A subject also refers to for
example, primates (e.g., humans, male or female), cows, sheep,
goats, horses, dogs, cats, rabbits, rats, mice, fish, birds and the
like. In certain embodiments, the subject is a primate. In yet
other embodiments, the subject is a human.
[0037] As used herein, a subject is "in need of" a treatment if
such subject would benefit biologically, medically or in quality of
life from such treatment.
[0038] The term "a therapeutically effective amount" of a compound
of the present invention refers to an amount of the compound of the
present invention that will elicit the biological or medical
response of a subject, for example, reduction or inhibition of an
enzyme or a protein activity, or ameliorate symptoms, alleviate
conditions, slow or delay disease progression, or prevent a
disease, etc. In one non-limiting embodiment, the term "a
therapeutically effective amount" refers to the amount of the
compound of the present invention that, when administered to a
subject, is effective to (1) at least partially alleviating,
inhibiting, preventing and/or ameliorating a condition, or a
disorder or a disease (i) mediated by BACE-1 or (ii) associated
with BACE-1 activity, or (iii) characterized by activity (normal or
abnormal) of BACE-1; or (2) reducing or inhibiting the activity of
BACE-1. In another non-limiting embodiment, the term "a
therapeutically effective amount" refers to the amount of the
compound of the present invention that, when administered to a
cell, or a tissue, or a non-cellular biological material, or a
medium, is effective to at least partially reduce or inhibit the
activity of BACE-1. The meaning of the term "a therapeutically
effective amount" as illustrated in the above embodiments for
BACE-1 also applies by the same means to any other relevant
proteins/peptides/enzymes, such as BACE-2, or cathepsin D.
[0039] As used herein, the term "treat", "treating" or "treatment"
of any disease or disorder refers in one embodiment, to
ameliorating the disease or disorder (i.e., slowing or arresting or
reducing the development of the disease or at least one of the
clinical symptoms thereof). In another embodiment, "treat",
"treating" or "treatment" refers to modulating the disease or
disorder, either physically, (e.g., stabilization of a discernible
symptom), physiologically, (e.g., stabilization of a physical
parameter), or both.
DETAILED DESCRIPTION OF THE INVENTION
[0040] The present invention provides compounds and pharmaceutical
compositions thereof that may be useful in the treatment or
prevention of diseases, conditions and/or disorders modulated by
BACE inhibition.
Embodiment 1
[0041] A compound of formula (I), or a pharmaceutically acceptable
salt thereof, as defined above in the first aspect of the
invention.
Embodiment 2
[0042] A compound of formula (I), or a pharmaceutically acceptable
salt thereof, as defined above in the second aspect of the
invention.
Embodiment 3
[0043] A compound of formula (I), or a pharmaceutically acceptable
salt thereof, as defined above in the third aspect of the
invention.
Embodiment 4
[0044] A compound according to any one of Embodiments 1 to 3, or a
pharmaceutically acceptable salt thereof, wherein R.sup.1 and
R.sup.2 are independently hydrogen or fluoro.
Embodiment 5
[0045] A compound according to any one of Embodiments 1 to 4, or a
pharmaceutically acceptable salt thereof, wherein R.sup.1 and
R.sup.2 are both fluoro.
Embodiment 6
[0046] A compound according to any one of Embodiments 1 to 5, or a
pharmaceutically acceptable salt thereof, wherein R.sup.3 and
R.sup.4 are independently hydrogen or methyl.
Embodiment 7
[0047] A compound according to any one of Embodiments 1 to 6, or a
pharmaceutically acceptable salt thereof, wherein R.sup.3 and
R.sup.4 are both hydrogen.
Embodiment 8
[0048] A compound according to any one of Embodiments 1 to 7, or a
pharmaceutically acceptable salt thereof, wherein R.sup.5 is
methyl, fluoromethyl, difluoromethyl, methoxymethyl, methoxyethyl,
ethoxymethyl or ethoxyethyl.
Embodiment 9
[0049] A compound according to any one of Embodiments 1 to 8, or a
pharmaceutically acceptable salt thereof, wherein R.sup.5 is
methyl.
Embodiment 10
[0050] A compound according to any one of Embodiments 1 to 9, or a
pharmaceutically acceptable salt thereof, wherein R.sup.6 is phenyl
or a 5- or 6-membered monocyclic heteroaryl comprising 1, 2, 3 or 4
heteroatoms independently selected from N, 0 and S, and wherein
said phenyl or heteroaryl is optionally substituted by 1, 2, 3 or 4
substituents independently selected from halogen, cyano, amino,
hydroxy, C.sub.1-4alkyl, halogen-C.sub.1-4alkyl,
halogen-C.sub.1-4alkylthio, halogen-C.sub.1-4alkoxy,
C.sub.1-4alkoxy, C.sub.1-4alkoxy-C.sub.1-4alkyl,
C.sub.1-4alkoxy-C.sub.1-4alkoxy and
C.sub.1-4alkoxy-C.sub.1-4alkylthio.
Embodiment 11
[0051] A compound according to any one of Embodiments 1 to 9, or a
pharmaceutically acceptable salt thereof, wherein R.sup.6 is a
6-membered monocyclic heteroaryl comprising 1, 2, 3 or 4
heteroatoms independently selected from N, O and S, and wherein
said phenyl or heteroaryl is optionally substituted by 1, 2, 3 or 4
substituents independently selected from halogen, cyano, amino,
hydroxy, C.sub.1-4alkyl, halogen-C.sub.1-4alkyl,
halogen-C.sub.1-4alkylthio, halogen-C.sub.1-4alkoxy,
C.sub.1-4alkoxy, C.sub.1-4alkoxy-C.sub.1-4alkyl,
C.sub.1-4alkoxy-C.sub.1-4alkoxy and
C.sub.1-4alkoxy-C.sub.1-4alkylthio.
Embodiment 12
[0052] A compound according to any one of Embodiments 1 to 9, or a
pharmaceutically acceptable salt thereof, wherein R.sup.6 is a
pyridyl or pyrazinyl group which is optionally substituted by 1, 2
or 3 substituents independently selected from halogen, cyano,
amino, hydroxy, C.sub.1-4alkyl, halogen-C.sub.1-4alkyl,
halogen-C.sub.1-4alkylthio, halogen-C.sub.1-4alkoxy,
C.sub.1-4alkoxy, C.sub.1-4alkoxy-C.sub.1-4alkyl,
C.sub.1-4alkoxy-C.sub.1-4alkoxy and
C.sub.1-4alkoxy-C.sub.1-4alkylthio.
Embodiment 13
[0053] A compound according to any one of Embodiments 1 to 9, or a
pharmaceutically acceptable salt thereof, wherein R.sup.6 is a
pyridyl or pyrazinyl group which is optionally substituted by 1, 2
or 3 substituents independently selected from halogen, cyano,
amino, hydroxy, C.sub.1-4alkyl, halogen-C.sub.1-4alkyl,
halogen-C.sub.1-4alkylthio, halogen-C.sub.1-4alkoxy,
C.sub.1-4alkoxy, C.sub.1-4alkoxy-C.sub.1-4alkyl,
C.sub.1-4alkoxy-C.sub.1-4alkoxy,
C.sub.1-4alkoxy-C.sub.1-4alkylthio,
C.sub.1-4alkoxy-C.sub.2-4alkenyl, C.sub.1-4alkoxy-C.sub.2-4alkynyl,
hydroxy-C.sub.1-4alkyl, hydroxy-C.sub.2-4alkenyl and
hydroxy-C.sub.2-4alkynyl.
Embodiment 14
[0054] A compound according to any one of Embodiments 1 to 9, or a
pharmaceutically acceptable salt thereof, wherein R.sup.6 is a
pyridin-2-yl group or a pyrazin-2-yl group which is substituted by
2 substituents and wherein one of the substituents is located at
the para position and one of the substituents is located at the
ortho position of the pyridin-2-yl or pyrazin-2-yl group relative
to the amide linker and wherein the substituents are independently
selected from halogen, cyano, amino, hydroxy, C.sub.1-4alkyl,
halogen-C.sub.1-4alkyl, halogen-C.sub.1-4alkylthio,
halogen-C.sub.1-4alkoxy, C.sub.1-4alkoxy,
C.sub.1-4alkoxy-C.sub.1-4alkyl, C.sub.1-4alkoxy-C.sub.1-4alkoxy,
C.sub.1-4alkoxy-C.sub.1-4alkylthio,
C.sub.1-4alkoxy-C.sub.2-4alkenyl, C.sub.1-4alkoxy-C.sub.2-4alkynyl,
hydroxy-C.sub.1-4alkyl, hydroxy-C.sub.2-4alkenyl and
hydroxy-C.sub.2-4alkynyl.
Embodiment 15
[0055] A compound according to any one of Embodiments 1 to 9, or a
pharmaceutically acceptable salt thereof, wherein R.sup.6 is a
pyridin-2-yl group which is substituted by 2 substituents and
wherein one of the substituents is located at the para position and
one of the substituents is located at the ortho position of the
pyridin-2-yl group relative to the amide linker and wherein the
substituents are independently selected from halogen, cyano, amino,
hydroxy, C.sub.1-4alkyl, halogen-C.sub.1-4alkyl,
halogen-C.sub.1-4alkylthio, halogen-C.sub.1-4alkoxy,
C.sub.1-4alkoxy, C.sub.1-4alkoxy-C.sub.1-4alkyl,
C.sub.1-4alkoxy-C.sub.1-4alkoxy and
C.sub.1-4alkoxy-C.sub.1-4alkylthio.
Embodiment 16
[0056] A compound according to any one of Embodiments 1 to 9, or a
pharmaceutically acceptable salt thereof, wherein R.sup.6 is a
pyridin-2-yl group which is substituted by 2 substituents and
wherein one of the substituents is located at the para position and
one of the substituents is located at the ortho position of the
pyridin-2-yl group relative to the amide linker and wherein the
substituents are independently selected from halogen, cyano, amino,
hydroxy, methyl, trifluoromethyl, methoxy, trifluoromethoxy,
3-fluoro-propoxy, fluoromethoxy, 3-methoxy-propynyl,
2-methoxy-ethoxy and 3-hydroxy-propynyl.
Embodiment 17
[0057] A compound according to any one of Embodiments 1 to 9, or a
pharmaceutically acceptable salt thereof, wherein R.sup.6 is a
pyridin-2-yl group which is substituted by 2 substituents and
wherein one of the substituents is located at the para position and
one of the substituents is located at the ortho position of the
pyridin-2-yl group relative to the amide linker and wherein the
substituents are independently selected from halogen, cyano, amino,
hydroxy, methyl, trifluoromethyl, methoxy and trifluoromethoxy.
Embodiment 18
[0058] A compound according to any one of Embodiments 1 to 9, or a
pharmaceutically acceptable salt thereof, wherein R.sup.6 is a
pyrazin-2-yl group which is substituted by 2 substituents and
wherein one of the substituents is located at the para position and
one of the substituents is located at the ortho position of the
pyrazin-2-yl group relative to the amide linker and wherein the
substituents are independently selected from halogen, cyano, amino,
hydroxy, methyl, trifluoromethyl, methoxy, trifluoromethoxy,
3-fluoro-propoxy, fluoromethoxy, 3-methoxy-propynyl,
2-methoxy-ethoxy and 3-hydroxy-propynyl.
Embodiment 19
[0059] A compound according to any one of Embodiments 1 to 9, or a
pharmaceutically acceptable salt thereof, wherein R.sup.6 is
5-cyano-3-methyl-pyridin-2-yl.
Embodiment 20
[0060] A compound according to any one of Embodiments 1 to 9, or a
pharmaceutically acceptable salt thereof, wherein R.sup.6 is
3-chloro-5-trifluoromethyl-pyridin-2-yl.
Embodiment 21
[0061] A compound according to Embodiment 3 of formula (Ia), or a
pharmaceutically acceptable salt thereof,
##STR00005##
wherein R.sup.1 and R.sup.2 are independently hydrogen or halogen;
R.sup.3 and R.sup.4 are independently hydrogen or C.sub.1-3alkyl;
or R.sup.3 and R.sup.4 taken together are cyclopropyl; R.sup.5 is
C.sub.1-3alkyl, halogen-C.sub.1-3alkyl or
C.sub.1-3alkoxy-C.sub.1-3alkyl; and R.sup.6 is phenyl or a 5- or
6-membered monocyclic heteroaryl comprising 1, 2, 3 or 4
heteroatoms independently selected from N, O and S, and wherein
said phenyl or heteroaryl is optionally substituted by 1, 2, 3 or 4
substituents independently selected from halogen, cyano, amino,
hydroxy, C.sub.1-4alkyl, halogen-C.sub.1-4alkyl,
halogen-C.sub.1-4alkylthio, halogen-C.sub.1-4alkoxy,
C.sub.1-4alkoxy, C.sub.1-4alkoxy-C.sub.1-4alkyl,
C.sub.1-4alkoxy-C.sub.1-4alkoxy and
C.sub.1-4alkoxy-C.sub.1-4alkylthio.
Embodiment 22
[0062] A compound according to Embodiment 3 of formula (Ib), or a
pharmaceutically acceptable salt thereof,
##STR00006##
wherein R.sup.3 and R.sup.4 are independently hydrogen or methyl;
and R.sup.6 is a 6-membered monocyclic heteroaryl comprising 1, 2,
3 or 4 heteroatoms independently selected from N, O and S, and
wherein said phenyl or heteroaryl is optionally substituted by 1,
2, 3 or 4 substituents independently selected halogen, cyano,
amino, hydroxy, C.sub.1-4alkyl, halogen-C.sub.1-4alkyl,
halogen-C.sub.1-4alkylthio, halogen-C.sub.1-4alkoxy,
C.sub.1-4alkoxy, C.sub.1-4alkoxy-C.sub.1-4alkyl,
C.sub.1-4alkoxy-C.sub.1-4alkoxy and
C.sub.1-4alkoxy-C.sub.1-4alkylthio.
Embodiment 23
[0063] A compound according to Embodiment 3 of formula (Ic), or a
pharmaceutically acceptable salt thereof,
##STR00007##
wherein R.sup.6 is a pyridin-2-yl group which is substituted by 2
substituents and wherein one of the substituents is located at the
para position and one of the substituents is located at the ortho
position of the pyridin-2-yl group relative to the amide linker and
wherein the substituents are independently selected from halogen,
cyano, amino, hydroxy, methyl, trifluoromethyl, methoxy and
trifluoromethoxy.
Embodiment 24
[0064] A compound according to Embodiment 3 of formula (Ic), or a
pharmaceutically acceptable salt thereof,
##STR00008##
wherein R.sup.6 is a pyrazin-2-yl group which is substituted by 2
substituents and wherein one of the substituents is located at the
para position and one of the substituents is located at the ortho
position of the pyrazin-2-yl group relative to the amide linker and
wherein the substituents are independently selected from halogen,
cyano, amino, hydroxy, methyl, trifluoromethyl, methoxy and
trifluoromethoxy.
Embodiment 25
[0065] A compound according to Embodiment 2, which is selected
from: [0066] 5-Cyano-3-methyl-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0067]
3-Chloro-5-cyano-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0068]
3-Chloro-5-cyano-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4,6,6-trimethyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-
-5-fluoro-pyridin-2-yl]-amide; [0069]
5-Cyano-3-methyl-pyridine-2-carboxylic acid
{6-[2-amino-5,5-difluoro-4-(2-methoxy-ethyl)-5,6-dihydro-4H-[1,3]oxazin-4-
-yl]-5-fluoro-pyridin-2-yl}-amide; [0070]
3-Chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
{6-[2-amino-5,5-difluoro-4-(2-methoxy-ethyl)-5,6-dihydro-4H-[1,3]oxazin-4-
-yl]-5-fluoro-pyridin-2-yl}-amide; [0071]
3-Chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0072]
3-Amino-5-trifluoromethyl-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0073] 3,5-Dichloro-pyridine-2-carboxylic
acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0074]
3-Amino-5-(2,2,2-trifluoro-ethoxy)pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0075]
3-Amino-5-(2,2-difluoro-ethoxy)-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0076]
3-Amino-5-(3-fluoro-propoxy)-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0077]
5-Methoxy-3-methyl-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-
-fluoro-pyridin-2-yl]-amide; [0078]
3-Amino-5-(3-methoxy-prop-1-ynyl)-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]amide; [0079]
3-Amino-5-fluoromethoxy-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0080]
3-Amino-5-(2-methoxy-ethoxy)-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0081]
3-Amino-5-(3-hydroxy-prop-1-ynyl)-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0082]
3-Amino-5-fluoro-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0083]
3-Amino-5-chloro-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]amide; [0084] 3-Chloro-pyridine-2-carboxylic
acid[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0085]
3-Chloro-5-(3-methoxy-prop-1-ynyl)pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0086]
3-Amino-5-difluoromethyl-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0087]
3-Amino-5-(2-chloro-ethoxy)-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0088]
3-Chloro-5-(2,2-difluoro-ethoxy)-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0089]
3-Amino-5-(2-fluoro-ethoxy)-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0090]
3-Chloro-5-fluoromethoxy-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0091]
3-Chloro-5-ethoxy-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-
-fluoro-pyridin-2-yl]amide; [0092]
3-Amino-5-(penta-deutero-ethoxy)-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0093]
3-Amino-5-(2-methoxy-ethyl)-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0094]
4-Chloro-1-difluoromethyl-1H-pyrazole-3-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0095] 3-Amino-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0096]
3-Chloro-5-(3-hydroxy-prop-1-ynyl)-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]amide; [0097]
3-Amino-5-difluoromethyl-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0098]
3-Amino-6-chloro-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0099] 5-Cyano-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; [0100]
3-Chloro-5-(1,1-difluoro-ethyl)-pyridine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; and [0101]
3-Amino-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic acid
[6-(2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluo-
ro-pyridin-2-yl]-amide; and pharmaceutically acceptable salts
thereof.
Embodiment 26
[0102] A compound according to Embodiment 2, which is selected
from: [0103] 5-Cyano-3-methyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0104]
3-Chloro-5-cyano-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-y-
l)-5-fluoro-pyridin-2-yl]-amide; [0105]
3-Chloro-5-cyano-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4,6,6-trimethyl-5,6-dihydro-4H-[1,3]oxazin-4-
-yl)-5-fluoro-pyridin-2-yl]-amide; [0106]
5-Cyano-3-methyl-pyridine-2-carboxylic acid
{6-[(R)-2-amino-5,5-difluoro-4-(2-methoxy-ethyl)-5,6-dihydro-4H-[1,3]oxaz-
in-4-yl]-5-fluoro-pyridin-2-yl}-amide; [0107]
3-Chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
{6-[(R)-2-amino-5,5-difluoro-4-(2-methoxy-ethyl)-5,6-dihydro-4H-[1,3]oxaz-
in-4-yl]-5-fluoro-pyridin-2-yl}-amide; [0108]
3-Chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0109]
3-Amino-5-trifluoromethyl-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0110]
3,5-Dichloro-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0111]
3-Amino-5-(2,2,2-trifluoro-ethoxy)pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0112]
3-Amino-5-(2,2-difluoro-ethoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0113]
3-Amino-5-(3-fluoro-propoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0114]
5-Methoxy-3-methyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0115]
3-Amino-5-(3-methoxy-prop-1-ynyl)-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0116]
3-Amino-5-fluoromethoxy-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0117]
3-Amino-5-(2-methoxy-ethoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]amide; [0118]
3-Amino-5-(3-hydroxy-prop-1-ynyl)-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0119]
3-Amino-5-fluoro-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-y-
l)-5-fluoro-pyridin-2-yl]-amide; [0120]
3-Amino-5-chloro-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0121] 3-Chloro-pyridine-2-carboxylic
acid[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl-
)-5-fluoro-pyridin-2-yl]-amide; [0122]
3-Chloro-5-(3-methoxy-prop-1-ynyl)pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0123]
3-Amino-5-difluoromethyl-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0124]
3-Amino-5-(2-chloro-ethoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0125]
3-Chloro-5-(2,2-difluoro-ethoxy)-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0126]
3-Amino-5-(2-fluoro-ethoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0127]
3-Chloro-5-fluoromethoxy-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0128]
3-Chloro-5-ethoxy-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-y-
l)-5-fluoro-pyridin-2-yl]-amide; [0129]
3-Amino-5-(penta-deutero-ethoxy)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0130]
3-Amino-5-(2-methoxy-ethyl)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]amide; [0131]
4-Chloro-1-difluoromethyl-1H-pyrazole-3-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0132] 3-Amino-pyrazine-2-carboxylic
acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0133]
3-Chloro-5-(3-hydroxy-prop-1-ynyl)-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0134]
3-Amino-5-difluoromethyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0135]
3-Amino-6-chloro-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0136] 5-Cyano-pyridine-2-carboxylic
acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; [0137]
3-Chloro-5-(1,1-difluoro-ethyl)-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; and [0138]
3-Amino-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide; and pharmaceutically acceptable salts
thereof.
[0139] On account of one or more than one asymmetrical carbon atom,
which may be present in a compound of the formula (I), a
corresponding compound of the formula (I) may exist in pure
optically active form or in the form of a mixture of optical
isomers, e.g. in the form of a racemic mixture. All of such pure
optical isomers and all of their mixtures, including the racemic
mixtures, are part of the present invention unless the context
dictates otherwise (for example in an embodiment of the invention
clearly specifying a single enantiomer).
[0140] As used herein, the term "isomers" refers to different
compounds that have the same molecular formula but differ in
arrangement and configuration of the atoms. Also as used herein,
the term "an optical isomer" or "a stereoisomer" refers to any of
the various stereo isomeric configurations which may exist for a
given compound of the present invention and includes geometric
isomers. It is understood that a substituent may be attached at a
chiral center of a carbon atom. The term "chiral" refers to
molecules which have the property of non-superimposability on their
mirror image partner, while the term "achiral" refers to molecules
which are superimposable on their mirror image partner. Therefore,
unless the context dictates otherwise (for example in an embodiment
of the invention clearly specifying a single enantiomer) the
invention includes enantiomers, diastereomers or racemates of the
compound. "Enantiomers" are a pair of stereoisomers that are
non-superimposable mirror images of each other. A 1:1 mixture of a
pair of enantiomers is a "racemic" mixture. The term is used to
designate a racemic mixture where appropriate. "Diastereoisomers"
are stereoisomers that have at least two asymmetric atoms, but
which are not mirror-images of each other. The absolute
stereochemistry is specified according to the Cahn-Ingold-Prelog
R-S system. When a compound is a pure enantiomer the
stereochemistry at each chiral carbon may be specified by either R
or S. Resolved compounds whose absolute configuration is unknown
can be designated (+) or (-) depending on the direction (dextro- or
levorotatory) which they rotate plane polarized light at the
wavelength of the sodium D line. Certain compounds described herein
contain one or more asymmetric centers or axes and may thus give
rise to enantiomers, diastereomers, and other stereoisomeric forms
that may be defined, in terms of absolute stereochemistry, as (R)-
or (S)-.
[0141] Depending on the choice of the starting materials and
procedures, the compounds can be present in the form of one of the
possible isomers or as mixtures thereof, for example as pure
optical isomers, or as isomer mixtures, such as racemates and
diastereoisomer mixtures, depending on the number of asymmetric
carbon atoms. The present invention is meant to include all such
possible isomers, including racemic mixtures, diasteriomeric
mixtures and optically pure forms. Optically active (R)- and
(S)-isomers may be prepared using chiral synthons or chiral
reagents, or resolved using conventional techniques. If the
compound contains a double bond, the substituent may be E or Z
configuration. If the compound contains a disubstituted cycloalkyl,
the cycloalkyl substituent may have a cis- or
trans-configuration.
[0142] In one embodiment of the invention, there is provided a
compound of the Examples having one chiral center as an isolated
stereoisomer in the R configuration.
[0143] In one embodiment of the invention, there is provided a
compound of the Examples having one chiral center as an isolated
stereoisomer in the S configuration.
[0144] In one embodiment of the invention, there is provided a
compound of the Examples having one chiral center as a racemic
mixture.
[0145] It is also possible that the intermediates and compounds of
the present invention may exist in different tautomeric forms, and
all such forms are embraced within the scope of the invention. The
term "tautomer" or "tautomeric form" refers to structural isomers
of different energies which are interconvertible via a low energy
barrier. For example, proton tautomers (also known as prototropic
tautomers) include interconversions via migration of a proton, such
as keto-enol and imine-enamine isomerizations. A specific example
of a proton tautomer is the imidazole moiety where the proton may
migrate between the two ring nitrogens. Valence tautomers include
interconversions by reorganization of some of the bonding
electrons.
[0146] Any resulting mixtures of isomers can be separated on the
basis of the physicochemical differences of the constituents, into
the pure or substantially pure geometric or optical isomers,
diastereomers, racemates, for example, by chromatography and/or
fractional crystallization.
[0147] Any resulting racemates of final products or intermediates
can be resolved into the optical antipodes by known methods, e.g.,
by separation of the diastereomeric salts thereof, obtained with an
optically active acid or base, and liberating the optically active
acidic or basic compound. In particular, a basic moiety may thus be
employed to resolve the compounds of the present invention into
their optical antipodes, e.g., by fractional crystallization of a
salt formed with an optically active acid, e.g., tartaric acid,
dibenzoyl tartaric acid, diacetyl tartaric acid, di-O,O'-p-toluoyl
tartaric acid, mandelic acid, malic acid or camphor-10-sulfonic
acid. Racemic products can also be resolved by chiral
chromatography, e.g., high pressure liquid chromatography (HPLC)
using a chiral adsorbent.
[0148] As used herein, the terms "salt" or "salts" refers to an
acid addition salt of a compound of the invention. "Salts" include
in particular "pharmaceutical acceptable salts". The term
"pharmaceutically acceptable salts" refers to salts that retain the
biological effectiveness and properties of the compounds of this
invention and, which typically are not biologically or otherwise
undesirable. The compounds of the present invention may be capable
of forming acid salts by virtue of the presence of amino groups or
groups similar thereto.
[0149] In one embodiment, the invention relates to a compound of
the formula (I), (Ia), (Ib) or (Ic) as defined herein, in free
form. In another embodiment, the invention relates to a compound of
the formula (I), (Ia), (Ib) or (Ic) as defined herein, in salt
form. In another embodiment, the invention relates to a compound of
the formula (I), (Ia), (Ib) or (Ic) as defined herein, in acid
addition salt form. In a further embodiment, the invention relates
to a compound of the formula (I), (Ia), (Ib) or (Ic) as defined
herein, in pharmaceutically acceptable salt form. In yet a further
embodiment, the invention relates to a compound of the formula (I),
(Ia), (Ib) or (Ic) as defined herein, in pharmaceutically
acceptable acid addition salt form. In yet a further embodiment,
the invention relates to a compound of the formula (I), (Ia), (Ib)
or (Ic) as defined herein, in hydrochloride salt form. In yet a
further embodiment, the invention relates to any one of the
compounds of the Examples in free form. In yet a further
embodiment, the invention relates to any one of the compounds of
the Examples in salt form. In yet a further embodiment, the
invention relates to any one of the compounds of the Examples in
acid addition salt form. In yet a further embodiment, the invention
relates to any one of the compounds of the Examples in
pharmaceutically acceptable salt form. In still another embodiment,
the invention relates to any one of the compounds of the Examples
in pharmaceutically acceptable acid addition salt form. In still
another embodiment, the invention relates to any one of the
compounds of the Examples in hydrochloride salt form.
[0150] Pharmaceutically acceptable acid addition salts can be
formed with inorganic acids and organic acids, e.g., acetate,
aspartate, benzoate, besylate, bromide/hydrobromide,
bicarbonate/carbonate, bisulfate/sulfate, camphorsulfonate,
chloride/hydrochloride, chlortheophyllonate, citrate,
ethandisulfonate, fumarate, gluceptate, gluconate, glucuronate,
hippurate, hydroiodide/iodide, isethionate, lactate, lactobionate,
laurylsulfate, malate, maleate, malonate, mandelate, mesylate,
methylsulphate, naphthoate, napsylate, nicotinate, nitrate,
octadecanoate, oleate, oxalate, palmitate, pamoate,
phosphate/hydrogen phosphate/dihydrogen phosphate,
polygalacturonate, propionate, stearate, succinate,
sulfosalicylate, tartrate, tosylate and trifluoroacetate salts.
[0151] Inorganic acids from which salts can be derived include, for
example, hydrochloric acid, hydrobromic acid, sulfuric acid, nitric
acid, phosphoric acid, and the like.
[0152] Organic acids from which salts can be derived include, for
example, acetic acid, propionic acid, glycolic acid, oxalic acid,
maleic acid, malonic acid, succinic acid, fumaric acid, tartaric
acid, citric acid, benzoic acid, mandelic acid, methanesulfonic
acid, ethanesulfonic acid, toluenesulfonic acid, sulfosalicylic
acid, and the like. Pharmaceutically acceptable base addition salts
can be formed with inorganic and organic bases.
[0153] The pharmaceutically acceptable salts of the present
invention can be synthesized from an acidic moiety, by conventional
chemical methods. Generally, such salts can be prepared by reacting
free base forms of these compounds with a stoichiometric amount of
the appropriate acid. Such reactions are typically carried out in
water or in an organic solvent, or in a mixture of the two.
Generally, use of non-aqueous media like ether, ethyl acetate,
ethanol, isopropanol, or acetonitrile is desirable, where
practicable. Lists of additional suitable salts can be found, e.g.,
in "Remington's Pharmaceutical Sciences", 20th ed., Mack Publishing
Company, Easton, Pa., (1985); and in "Handbook of Pharmaceutical
Salts: Properties, Selection, and Use" by Stahl and Wermuth
(Wiley-VCH, Weinheim, Germany, 2002).
[0154] Furthermore, the compounds of the present invention,
including their salts, may also be obtained in the form of their
hydrates, or include other solvents used for their crystallization.
The compounds of the present invention may inherently or by design
form solvates with pharmaceutically acceptable solvents (including
water); therefore, it is intended that the invention embrace both
solvated and unsolvated forms. The term "solvate" refers to a
molecular complex of a compound of the present invention (including
pharmaceutically acceptable salts thereof) with one or more solvent
molecules. Such solvent molecules are those commonly used in the
pharmaceutical art, which are known to be innocuous to the
recipient, e.g., water, ethanol, and the like. The term "hydrate"
refers to the complex where the solvent molecule is water.
[0155] Compounds of the invention, i.e. compounds of formula (I)
that contain groups capable of acting as donors and/or acceptors
for hydrogen bonds may be capable of forming co-crystals with
suitable co-crystal formers. These co-crystals may be prepared from
compounds of formula (I) by known co-crystal forming procedures.
Such procedures include grinding, heating, co-subliming,
co-melting, or contacting in solution compounds of formula (I) with
the co-crystal former under crystallization conditions and
isolating co-crystals thereby formed. Suitable co-crystal formers
include those described in WO 2004/078163. Hence the invention
further provides co-crystals comprising a compound of formula
(I).
[0156] The compounds of the present invention, including salts,
hydrates and solvates thereof, may inherently or by design form
polymorphs.
[0157] Any formula given herein is also intended to represent
unlabeled forms as well as isotopically labeled forms of the
compounds. Isotopically labeled compounds have structures depicted
by the formulas given herein except that one or more atoms are
replaced by an atom having a selected atomic mass or mass number.
Examples of isotopes that can be incorporated into compounds of the
invention include isotopes of hydrogen, carbon, nitrogen, oxygen,
phosphorous, fluorine, and chlorine, such as .sup.2H, .sup.3H,
.sup.11C, .sup.13C, .sup.14C, .sup.15N, .sup.18F .sup.31P,
.sup.32P, .sup.35S, .sup.36Cl, .sup.125I respectively. The
invention includes various isotopically labeled compounds as
defined herein, for example those into which radioactive isotopes,
such as .sup.3H and .sup.14C, or those into which non-radioactive
isotopes, such as .sup.2H and .sup.13C are present. Such
isotopically labelled compounds are useful in metabolic studies
(with .sup.14C), reaction kinetic studies (with, for example
.sup.2H or .sup.3H), detection or imaging techniques, such as
positron emission tomography (PET) or single-photon emission
computed tomography (SPECT) including drug or substrate tissue
distribution assays, or in radioactive treatment of patients. In
particular, an .sup.18F or labeled compound may be particularly
desirable for PET or SPECT studies. Isotopically-labeled compounds
of formula (I) can generally be prepared by conventional techniques
known to those skilled in the art or by processes analogous to
those described in the accompanying Examples and Preparations using
an appropriate isotopically-labeled reagents in place of the
non-labeled reagent previously employed.
[0158] Further, substitution with heavier isotopes, particularly
deuterium (i.e., .sup.2H or D) may afford certain therapeutic
advantages resulting from greater metabolic stability, for example
increased in vivo half-life or reduced dosage requirements or an
improvement in therapeutic index. It is understood that deuterium
in this context is regarded as a substituent of a compound of the
formula (I). The concentration of such a heavier isotope,
specifically deuterium, may be defined by the isotopic enrichment
factor. The term "isotopic enrichment factor" as used herein means
the ratio between the isotopic abundance and the natural abundance
of a specified isotope. If a substituent in a compound of this
invention is denoted deuterium, such compound has an isotopic
enrichment factor for each designated deuterium atom of at least
3500 (52.5% deuterium incorporation at each designated deuterium
atom), at least 4000 (60% deuterium incorporation), at least 4500
(67.5% deuterium incorporation), at least 5000 (75% deuterium
incorporation), at least 5500 (82.5% deuterium incorporation), at
least 6000 (90% deuterium incorporation), at least 6333.3 (95%
deuterium incorporation), at least 6466.7 (97% deuterium
incorporation), at least 6600 (99% deuterium incorporation), or at
least 6633.3 (99.5% deuterium incorporation).
[0159] Pharmaceutically acceptable solvates in accordance with the
invention include those wherein the solvent of crystallization may
be isotopically substituted, e.g. D.sub.2O, d.sub.6-acetone,
d.sub.6-DMSO.
[0160] Compounds of the present invention may be synthesized by
synthetic routes that include processes analogous to those
well-known in the chemical arts, particularly in light of the
description contained herein. The starting materials are generally
available from commercial sources such as Sigma-Aldrich or are
readily prepared using methods well known to those skilled in the
art (e.g., prepared by methods generally described in Louis F.
Fieser and Mary Fieser, Reagents for Organic Synthesis, v. 1-19,
Wiley, New York (1967-1999 ed.), or Beilsteins Handbuch der
organischen Chemie, 4, Aufl. ed. Springer-Verlag, Berlin, including
supplements (also available via the Beilstein online
database)).
[0161] For illustrative purposes, reaction schemes 1 and 2 depicted
below provide potential routes for synthesizing the compounds of
the present invention as well as key intermediates. For a more
detailed description of the individual reaction steps, see the
Examples section below. Those skilled in the art will appreciate
that other synthetic routes may be used to synthesize the inventive
compounds. Although specific starting materials and reagents are
depicted in the schemes and discussed below, other starting
materials and reagents can be easily substituted to provide a
variety of derivatives and/or reaction conditions. In addition,
many of the compounds prepared by the methods described below can
be further modified in light of this disclosure using conventional
chemistry well known to those skilled in the art.
##STR00009## ##STR00010##
##STR00011## ##STR00012##
[0162] In a further aspect, the invention relates to a process for
the preparation of a compound of the formula (I), in free form or
in pharmaceutically acceptable salt form, comprising
[0163] a) the reaction of a compound of the formula
##STR00013##
in free form or in salt form, in which R.sup.1, R.sup.2, R.sup.3,
R.sup.4 and R.sup.5 are as defined for the formula I and PG is a
protecting group, for example N-tert-butoxycarbonyl, with a
compound of the formula
##STR00014##
in free form or in salt form, in which R.sup.6 is as defined for
the formula I and L is a leaving group, for example a hydroxyl
group,
[0164] b) the reaction of a compound of the formula
##STR00015##
in free form or in salt form, in which R.sup.1, R.sup.2, R.sup.3,
R.sup.4 and R.sup.5 are as defined for the formula I, Hal is
halogen, for example bromine, and PG is a protecting group, for
example N-tert-butoxycarbonyl, with a compound of the formula
##STR00016##
in free form or in salt form, in which R.sup.6 is as defined for
the formula I,
[0165] c) the optional reduction, oxidation or other
functionalisation of the resulting compound,
[0166] d) the cleavage of any protecting group(s) optionally
present and
[0167] e) the recovery of the so obtainable compound of the formula
I in free form or in salt form.
[0168] The above reactions can be effected according to
conventional methods. For example, the reaction described in step
(a) may be carried out in the presence of a suitable coupling
agent, for example 1-hydroxy-7-azabenzotriazole, a suitable
activating agent, for example
1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, and
optionally a suitable base, for example diisopropylethylamine, a
suitable solvent, for example dimethylformamide, and at a suitable
temperature, for example 0 to 50.degree. C., more suitably 0 to
25.degree. C.
[0169] The reaction described in step (b) may be carried out:
[0170] (i) in the presence of a suitable catalyst, for example
tris(dibenzylidene-acetone) di palladium, a suitable ligand, for
example Xantphos, a suitable base, for example cesium carbonate, a
suitable solvent, for example dioxane, and at a suitable
temperature, for example 10 to 100.degree. C., more suitably 30 to
85.degree. C.; or
[0171] (ii) in the presence of a suitable catalyst, for example
copper iodide, a suitable ligand, for example
rac-trans-N,N'-dimethylcyclohexane-1,2-diamine, a suitable base,
for example potassium carbonate, a suitable solvent, for example
dioxane, and at a suitable temperature, for example reflux
temperature.
[0172] The starting materials of the formulae II, IIa, III and IIIa
are known or may be prepared according to conventional procedures
starting from known compounds, may be prepared from known compounds
as described in the Examples, or may be prepared using procedures
analogous to those described in the Examples.
[0173] The further optional reduction, oxidation or other
functionalisation of compounds of formula (I) may be carried out
according to methods well know to those skilled in the art.
[0174] Within the scope of this text, only a readily removable
group that is not a constituent of the particular desired end
product of the compounds of the present invention is designated a
"protecting group", unless the context indicates otherwise. The
protection of functional groups by such protecting groups, the
protecting groups themselves, and their cleavage reactions are
described for example in standard reference works, such as J. F. W.
McOmie, "Protective Groups in Organic Chemistry", Plenum Press,
London and New York 1973, in T. W. Greene and P. G. M. Wuts,
"Protective Groups in Organic Synthesis", Third edition, Wiley, New
York 1999, in "The Peptides"; Volume 3 (editors: E. Gross and J.
Meienhofer), Academic Press, London and New York 1981, in "Methoden
der organischen Chemie" (Methods of Organic Chemistry), Houben
Weyl, 4th edition, Volume 15/I, Georg Thieme Verlag, Stuttgart
1974, and in H.-D. Jakubke and H. Jeschkeit, "Aminosauren, Peptide,
Proteine" (Amino acids, Peptides, Proteins), Verlag Chemie,
Weinheim, Deerfield Beach, and Basel 1982. A characteristic of
protecting groups is that they can be removed readily (i.e. without
the occurrence of undesired secondary reactions) for example by
solvolysis, reduction, photolysis or alternatively under
physiological conditions (e.g. by enzymatic cleavage).
[0175] Salts of compounds of the present invention having at least
one salt-forming group may be prepared in a manner known to those
skilled in the art. For example, acid addition salts of compounds
of the present invention are obtained in customary manner, e.g. by
treating the compounds with an acid or a suitable anion exchange
reagent.
[0176] Salts can be converted into the free compounds in accordance
with methods known to those skilled in the art. Acid addition salts
can be converted, for example, by treatment with a suitable basic
agent.
[0177] For those compounds containing an asymmetric carbon atom,
the compounds exist in individual optically active isomeric forms
or as mixtures thereof, e.g. as racemic or diastereomeric mixtures.
Diastereomeric mixtures can be separated into their individual
diastereoisomers on the basis of their physical chemical
differences by methods well known to those skilled in the art, such
as by chromatography and/or fractional crystallization. Enantiomers
can be separated by converting the enantiomeric mixture into a
diastereomeric mixture by reaction with an appropriate optically
active compound (e.g., chiral auxiliary such as a chiral alcohol or
Mosher's acid chloride), separating the diastereoisomers and
converting (e.g., hydrolyzing) the individual diastereoisomers to
the corresponding pure enantiomers. Enantiomers can also be
separated by use of a commercially available chiral HPLC
column.
[0178] The invention further includes any variant of the present
processes, in which the reaction components are used in the form of
their salts or optically pure material. Compounds of the invention
and intermediates can also be converted into each other according
to methods generally known to those skilled in the art.
[0179] Compounds of the formula (I), in free form or in
pharmaceutically acceptable salt form, herein-after often referred
to as "agents of the invention", exhibit valuable pharmacological
properties, when tested in vitro, and may, therefore, be useful in
medicaments, in therapy or for use as research chemicals, for
example as tool compounds.
[0180] For example, agents of the invention are inhibitors of
BACE-1 and BACE-2 and may be used for the treatment or prevention
of a condition, disease or disorder involving processing by such
enzymes, particularly the generation of beta-amyloid and the
subsequent aggregation into oligomers and fibrils, and loss of
.beta. cell mass and/or function.
[0181] The inhibiting properties of an agent of the invention
towards proteases can be evaluated in the tests as described
hereinafter.
Test 1: Inhibition of Human BACE-1
[0182] Recombinant BACE-1 (extracellular domain, expressed in
baculovirus and purified using standard methods) at 0.1 to 1 nM
concentrations is incubated with the test compound at various
concentrations for 1 hour at room temperature in 100 mM acetate
buffer, pH 4.5, containing 0.1% CHAPS. Activity was measured using
a final concentration of 3 .mu.M of the fluorescence-quenched
substrate
Q-C(HSO.sub.3)-Ile-Asp-Leu-Ala-Val-Leu-Asp-HN-CH.sub.2-CH.sub.2-Mca,
where Q=2-nitro-5-amino benzoic acid and Mca=7-methoxy-4-coumarinyl
acetic acid. Catalytic turnover was monitored in a Spectramax
Gemini fluorescence plate reader (Molecular Devices) in black
96-well microplates using excitation/emission wavelength of 325 nm
and 400 nm, respectively. Fluorescence increase was followed for 15
min, in 1 minute's intervals. The fluorescence/time slopes were
calculated from duplicate wells and from wells without inhibitor
and the IC.sub.50 values were calculated using a logistic
4-parameter model.
Test 2: Inhibition of Human BACE-2
[0183] Recombinant BACE-2 (extracellular domain, expressed in
baculovirus and purified using standard methods) at 0.1 to 1 nM
concentrations is incubated with the test compound at various
concentrations for 1 hour at room temperature in 100 mM acetate
buffer, pH 4.5, containing 0.1% CHAPS. Activity was measured using
a final concentration of 3 .mu.M of the fluorescence-quenched
substrate
Q-C(HSO.sub.3)-Ile-Asp-Leu-Ala-Val-Leu-Asp-HN-CH.sub.2-CH.sub.2-Mca,
where Q=2-nitro-5-amino benzoic acid and Mca=7-methoxy-4-coumarinyl
acetic acid. Catalytic turnover was monitored in a Spectramax
Gemini fluorescence plate reader (Molecular Devices) in black
96-well microplates using excitation/emission wavelength of 325 nm
and 400 nm, respectively. Fluorescence increase was followed for 15
min, in 1 minute's intervals. The fluorescence/time slopes were
calculated from duplicate wells and from wells without inhibitor
and the IC.sub.50 values were calculated using a logistic
4-parameter model.
Test 3: Inhibition of Human Cathepsin D
[0184] Recombinant cathepsin D (expressed as procathepsin D in
baculovirus, purified using standard methods and activated by
incubation in sodium formate buffer pH 3.7) is incubated with the
test compound at various concentrations for 1 hour at room
temperature in sodium formate or sodium acetate buffer at a
suitable pH within the range of pH 3.0 to 5.0. Synthetic peptide
substrate
Mca-Gly-Lys-Pro-Ile-Leu-Phe-Phe-Arg-Leu-Lys(DNP)-D-Arg-NH.sub.2 is
added to a final concentration of 1 to 5 .mu.M, and the increase in
fluorescence is recorded at excitation of 325 nm and emission at
400 nm in a microplate spectro-fluorimeter for 5 to 30 minutes in
1-minute intervals. IC.sub.50 values are calculated from the
percentage of inhibition of cathepsin D-activity as a function of
the test compound concentration.
Test 4: Inhibition of Cellular Release of Amyloid Peptide 1-40
[0185] Chinese hamster ovary cells are transfected with the human
gene for amyloid precursor protein. The cells are plated at a
density of 8000 cells/well into 96-well microtiter plates and
cultivated for 24 hours in DMEM cell culture medium containing 10%
FCS. The test compound is added to the cells at various
concentrations, and the cells are cultivated for 24 hours in the
presence of the test compound. The supernatants are collected, and
the concentration of amyloid peptide 1-40 is determined using state
of the art immunoassay techniques, for example sandwich ELISA,
homogenous time-resolved fluorescence (HTRF) immunoassay, or
electro-chemiluminescence immunoassay. The potency of the compound
is calculated from the percentage of inhibition of amyloid peptide
release as a function of the test compound concentration.
[0186] The compounds of the Examples showed the IC.sub.50 values
presented in Table 1 below when tested in Tests 1, 2 and 4. NT=Not
Tested
TABLE-US-00001 TABLE 1 Test 4 Example Test 1 Test 2
Amyloid-.beta.1-40 No. BACE-1 IC.sub.50 [.mu.M] BACE-2 IC.sub.50
[.mu.M] release IC.sub.50 [.mu.M] 1 0.012 0.066 0.007 2 0.012 0.071
0.008 3 0.029 0.14 0.007 4 0.1 0.58 0.049 5 >10 >10 >10 6
0.65 6.6 0.38 7 0.035 0.29 0.027 8 0.16 1.4 0.14 9 0.018 0.004
0.012 10 0.59 3.8 0.6 11 0.83 2.9 0.44 12 1.2 >10 0.31 13 0.27
0.093 0.082 14 NT NT 0.54 15 0.11 0.73 0.030 16 0.12 8.9 NT 17 0.24
8.2 0.062 18 0.33 0.12 0.088 19 0.06 0.048 0.045 20 0.36 0.095
0.088 21 0.083 0.84 0.081 22 0.19 0.58 0.06 23 8.7 >10 2.9 24
0.24 4.5 0.25 25 0.57 >10 0.48 26 0.11 0.027 0.057 27 0.29 0.42
0.45 28 1.9 10 0.84 29 0.15 5.6 0.07 30 0.019 0.007 0.013 31 0.54
0.49 0.18 32 0.06 0.93 0.019 33 0.14 0.26 0.066 34 >10 >10
6.5 35 0.054 0.26 0.014 36 NT NT 0.058 37 0.064 >10 0.31
Test 5: In Vivo Inhibitory Activity of Example Compounds
[0187] Male Sprague-Dawley rats, 220-280 g weight, (Charles River,
France) were dosed by oral gavage with vehicle alone (0.1% Tween80,
0.5% methylcellulose in water) or with compound suspended in
vehicle at a dose of 10 micromoles compound per kilogram body
weight, 4 hours prior to sacrifice. The 4 hour timepoint was
selected in order to compare the activity of compounds that have
sufficient pharmacokinetic and biodistribution properties to reduce
total brain Abeta within approximately three half-lives of the rat
brain Abeta40 peptide.
[0188] Immediately prior to sacrifice, anaesthetized rat
(spontaneous inhalation, 2-5% Isoflurane and air) were fixed in a
stereotaxic apparatus on a raised platform, with anesthesia
maintained though a nose cone. The angle of the head was tilted
downward, perpendicular to the body, and a hypodermic needle
lowered through the skin behind the occipital ridge, into the
Cisterna magna. Cerebrospinal fluid (CSF) was withdrawn
(.about.-50-100 .mu.L), dispensed into tubes (protein Lo-bind
Eppendorf tubes for Abeta40 analysis, normal Eppendorph tubes for
compound analysis), frozen on dry ice and stored at -80.degree. C.
until analysis. Rats were then immediately decapitated under
anesthesia, trunk blood collected for analysis of compound levels
and the brain retrieved. One half-forebrain was dissected by
removing the cerebellum and olfactory bulbs, frozen in three pieces
on a metal plate pre-cooled on frozen CO.sub.2 and stored in tubes
at -80.degree. C. until analysis for Abeta40. For the other
half-brain, olfactory bulbs were discarded and a sagittal slice
taken from the medial aspect, weighing .about.200-400 mg, placed in
glass HPLC tubes and frozen on dry ice until analysis for compound
levels.
[0189] Soluble Abeta40 levels in the rat brain and CSF were
quantified using a Meso Scale Discovery (MSD) 96-well MULTI-ARRAY
human/rodent (4G8) Abeta40 Ultrasensitive Assay (#K110FTE-3, Meso
Scale Discovery, Gaithersburg, USA). Forebrain sample homogenates
were prepared by sonication in 9 volumes (w/v) of ice cold TBA.
Fifty .mu.L of 2% TX-100 in TBS-complete was added to 50 .mu.L
aliquots of the homogenate to reach a final concentration of 1%
TX-100 in a 1:20 dilution. Samples were incubated on ice for 15 min
interrupted with 3 short vortexing steps, then centrifuged (100
000.times.g, 4.degree. C., 15 min), and 50 .mu.L of supernatant
collected. This was further diluted 1:5 with 3% Blocker A solution
from the MSD kit to a final dilution of 1:100 and applied to the
MSD plate. CSF samples containing blood were excluded. All other
CSF samples were diluted with 1% Blocker A solution (from
manufacturers kit) to reach a 1:20 CSF dilution. Calibration curves
were prepared in 1% Blocker A solution spiked with synthetic
Abetal-40 peptide. Samples and calibration standards were applied
in duplicate at a volume of 25 .mu.L per well. Abeta40
concentrations of samples were estimated from the standard curve
using SOFTmax PRO 4.0.
[0190] The compounds of Examples 2, 3, 7 and 30 of the present
invention and those of Examples 22, 39 and 71 of WO 2011/069934 A1
showed the effects presented in Table 2 below on Abeta lowering in
rat brain and CSF when tested in Test 5. (n.s.=not statistically
significant (Student's t-test))
TABLE-US-00002 TABLE 2 Abeta Abeta lowering lowering in Example No.
Structure in rat forebrain rat CSF 7 Present Invention ##STR00017##
-63.6% -67.9% 39 WO 2011/069934 A1 ##STR00018## -1.4% (n.s.) -8.2%
(n.s.) 2 Present Invention ##STR00019## -67.1% -70.7% 22 WO
2011/069934 A1 ##STR00020## -7.8% (n.s.) -17.9% 3 Present Invention
##STR00021## -20.0% -35.3% 71 WO 2011/069934 A1 ##STR00022## -5.6%
(n.s.) -30.4% 30 Present Invention ##STR00023## -46.6% -55.2%
[0191] Blood, CSF and brain samples were also analyzed for compound
levels using liquid chromatography/tandem mass spectrometry methods
(LC/MS/MS). Brain samples were mixed with 2 volumes of
KH.sub.2PO.sub.4 buffer and homogenized using a Covaris.RTM.
device. Either 30 or 50 .mu.L of blood, CSF or tissue homogenate
were spiked with a structurally related internal standard and
subsequently mixed with an at least 4-fold excess volume
acetonitrile (protein precipitation). The supernatant was either
directly, or after dilution with water, injected into the LC/MS/MS
system for analysis.
[0192] Due to their inhibiting properties towards proteases, and
BACE-1 in particular, agents of the invention may be useful, e.g.,
in the treatment or prevention of a variety of disabilitating
psychiatric, psychotic, neurological or vascular states, e.g. of a
condition, disease or disorder of the vascular system or of the
nervous system, in which beta-amyloid generation or aggregation
plays a role. Based on the inhibition of BACE-2 (beta-site
APP-cleaving enzyme 2) or cathepsin D, which are close homologues
of the pepsin-type aspartyl proteases and beta-secretase, and the
correlation of BACE-2 or cathepsin D expression with a more
tumorigenic or metastatic potential of tumor cells, the agents of
the invention may also be useful as anti-cancer medicaments, e.g.
in the suppression of the metastasis process associated with tumor
cells. Furthermore, based on the inhibition of BACE-2 and the
correlation of BACE-2 activity with TME27 cleavage and .beta. cell
mass, the agents of the invention may also be useful for treating
or preventing loss of .beta. cell mass and/or function, e.g. in the
treatment of diabetes.
[0193] The said condition, disease or disorder of the vascular
system or of the nervous system is exemplified by, and includes,
without limitation, an anxiety disorder, such as panic disorder
with or without agoraphobia, agoraphobia without history of panic
disorder, an animal or other specific phobia, including a social
phobia, social anxiety disorder, anxiety, obsessive-compulsive
disorder, a stress disorder, including post-traumatic or acute
stress disorder, or a generalized or substance-induced anxiety
disorder; a neurosis; seizures; epilepsy, especially partial
seizures, simple, complex or partial seizures evolving to
secondarily generalized seizures or generalized seizures [absence
(typical or atypical), myoclonic, clonic, tonic, tonic-clonic or
atonic seizures]; convulsions; migraine; an affective disorder,
including a depressive or bipolar disorder, e.g. single-episode or
recurrent major depressive disorder, major depression, a dysthymic
disorder, dysthymia, depressive disorder NOS, bipolar I or bipolar
II manic disorder or cyclothymic disorder; a psychotic disorder,
including schizophrenia or depression; neurodegeneration, e.g.
neurodegeneration arising from cerebral ischemia; an acute,
traumatic or chronic degenerative process of the nervous system,
such as Parkinson's disease, Down's syndrome, dementia, e.g. senile
dementia, dementia with Lewy bodies or a fronto-temporal dementia,
a cognitive disorder, cognitive impairment, e.g. mild cognitive
impairment, memory impairment, an amyloid neuropathy, a peripheral
neuropathy, Alzheimer's disease, Gerstmann-Straeussler-Scheinker
syndrome, Niemann-Pick disease, e.g. Niemann-Pick type C disease,
brain inflammation, a brain, spinal cord or nerve injury, e.g.
traumatic brain injury (TBI), a nerve trauma or a brain trauma,
vascular amyloidosis, cerebral haemorrhage with amyloidosis,
Huntington's chorea, amyotrophic lateral sclerosis, multiple
sclerosis or fragile X syndrome; scrapie; cerebral amyloid
angiopathy; an encephalopathy, e.g. transmissible spongiform
encephalopathy; stroke; an attention disorder, e.g. attention
deficit hyperactivity disorder; Tourette's syndrome; a speech
disorder, including stuttering; a disorder of the circadian rhythm,
e.g. in subjects suffering from the effects of jet lag or shift
work; pain; nociception; itch; emesis, including acute, delayed or
anticipatory emesis, such as emesis induced by chemotherapy or
radiation, motion sickness, or post-operative nausea or vomiting;
an eating disorder, including anorexia nervosa or bulimia nervosa;
premenstrual syndrome; a muscle spasm or spasticity, e.g. in
paraplegic patients; a hearing disorder, e.g. tinnitus or
age-related hearing impairment; urinary incontinence; glaucoma;
inclusion-body myositis; or a substance-related disorder, including
substance abuse or dependency, including a substance, such as
alcohol, withdrawal disorder. Agents of the invention may also be
useful in enhancing cognition, e.g. in a subject suffering from a
dementing condition, such as Alzheimer's disease; as pre-medication
prior to anaesthesia or a minor medical intervention, such as
endoscopy, including gastric endoscopy; or as ligands, e.g.
radioligands or positron emission tomography (PET) ligands.
[0194] Due to their inhibiting properties towards BACE-2, compounds
of the invention may be useful in the treatment or prevention a
disease or disorder mediated by BACE-2. Diseases and disorders
associated with BACE-2 include: metabolic syndrome (such as
dyslipidemia, obesity, insulin resistance, hypertension,
microalbuminemia, hyperuricaemia, and hypercoagulability), insulin
resistance, glucose intolerance (also known as impaired glucose
tolerance or impaired glucose tolerance, IGT), obesity,
hypertension, or diabetic complications (such as retinopathy,
nephropathy, diabetic foot, ulcers, macroangiopathies, metabolic
acidosis or ketosis, reactive hypoglycaemia, hyperinsulinaemia),
glucose metabolic disorder, dyslipidaemias of different origins,
atherosclerosis and related diseases, high blood pressure, chronic
heart failure, Syndrome X, diabetes, non-insulin-dependent diabetes
mellitus, Type 2 diabetes, Type 1 diabetes, body weight disorders,
weight loss, body mass index and leptin related diseases.
[0195] Compounds of the invention may be suitable for preventing
beta-cell degeneration such as apoptosis or necrosis of pancreatic
beta cells, for improving or restoring the functionality of
pancreatic cells, and/or increasing the number and/or size of
pancreatic beta cells.
[0196] As used herein a patient is suffering from "obesity" if the
patient exhibits at least one of: [0197] a body mass index (BMI),
i.e. the patient's mass (in kg) divided by the square of the
patient's height (in m), of 30 or more; [0198] an absolute waist
circumference of >102 cm in men or >88 cm in women; [0199] a
waist-to-hip ratio >0.9 in men or >0.85 in women; or [0200] a
percent body fat >25% in men or >30% in women.
[0201] As used herein a patient is suffering from "Type 2 diabetes"
if they meet the World Health
[0202] Organisation criteria for Diabetes diagnosis (Definition and
diagnosis of diabetes mellitus and intermediate hyperglycaemia,
WHO, 2006), i.e. the patient exhibits at least one of: [0203] a
fasting plasma glucose .gtoreq.7.0 mmol/l (126 mg/dl); or [0204] a
venous plasma glucose 11.1 mmol/l (200 mg/dl) 2 hours after
ingestion of 75 g oral glucose load.
[0205] As used herein a patient is suffering from "IGT" if they
meet the World Health Organisation criteria for IGT diagnosis
(Definition and diagnosis of diabetes mellitus and intermediate
hyperglycaemia, WHO, 2006), i.e. the patient exhibits both of:
[0206] a fasting plasma glucose <7.0 mmol/l (126 mg/dl); and
[0207] a venous plasma glucose .gtoreq.7.8 and <11.1 mmol/l (200
mg/dl) 2 hours after ingestion of 75 g oral glucose load.
[0208] As used herein, the term "metabolic syndrome" is a
recognized clinical term used to describe a condition comprising
combinations of Type II diabetes, impaired glucose tolerance,
insulin resistance, hypertension, obesity, increased abdominal
girth, hypertriglyceridemia, low HDL, hyperuricaernia,
hypercoagulability and/or microalbuminemia. The American Heart
Association has published guidelines for the diagnosis of metabolic
syndrome, Grundy, S., et. al., (2006) Cardiol. Rev. Vol. 13, No. 6,
pp. 322-327.
[0209] For the above-mentioned indications, the appropriate dosage
will vary depending on, e.g., the compound employed as active
pharmaceutical ingredient, the host, the mode of administration,
the nature and severity of the condition, disease or disorder or
the effect desired. However, in general, satisfactory results in
animals are indicated to be obtained at a daily dosage of from
about 0.1 to about 100, preferably from about 1 to about 50, mg/kg
of animal body weight. In larger mammals, for example humans, an
indicated daily dosage is in the range of from about 0.5 to about
2000, preferably from about 2 to about 200, mg of an agent of the
invention conveniently administered, for example, in divided doses
up to four times a day or in sustained release form.
[0210] An agent of the invention may be administered by any
conventional route, in particular enterally, preferably orally,
e.g. in the form of a tablet or capsule, or parenterally, e.g. in
the form of an injectable solution or suspension.
[0211] In a further aspect, the invention relates to a
pharmaceutical composition comprising an agent of the invention as
active pharmaceutical ingredient in association with at least one
pharmaceutically acceptable carrier or diluent and optionally in
association with other auxiliary substances, such as inhibitors of
cytochrome P450 enzymes, agents preventing the degradation of
active pharmaceutical ingredients by cytochrome P450, agents
improving or enhancing the pharmacokinetics of active
pharmaceutical ingredients, agents improving or enhancing the
bioavailability of active pharmaceutical ingredients, and so on,
e.g. grapefruit juice, ketoconazole or, preferably, ritonavir. Such
a composition may be manufactured in conventional manner, e.g. by
mixing its components. Unit dosage forms contain, e.g., from about
0.1 to about 1000, preferably from about 1 to about 500, mg of an
agent of the invention.
[0212] In addition, the pharmaceutical compositions of the present
invention can be made up in a solid form (including without
limitation capsules, tablets, pills, granules, powders or
suppositories), or in a liquid form (including without limitation
solutions, suspensions or emulsions). The pharmaceutical
compositions can be subjected to conventional pharmaceutical
operations such as sterilization and/or can contain conventional
inert diluents, lubricating agents, or buffering agents, as well as
adjuvants, such as preservatives, stabilizers, wetting agents,
emulsifers and buffers, etc.
[0213] Typically, the pharmaceutical compositions are tablets or
gelatin capsules comprising the active ingredient together with
[0214] a) diluents, e.g., lactose, dextrose, sucrose, mannitol,
sorbitol, cellulose and/or glycine; [0215] b) lubricants, e.g.,
silica, talcum, stearic acid, its magnesium or calcium salt and/or
polyethyleneglycol; for tablets also [0216] c) binders, e.g.,
magnesium aluminum silicate, starch paste, gelatin, tragacanth,
methylcellulose, sodium carboxymethylcellulose and/or
polyvinylpyrrolidone; if desired [0217] d) disintegrants, e.g.,
starches, agar, alginic acid or its sodium salt, or effervescent
mixtures; and/or [0218] e) absorbents, colorants, flavors and
sweeteners.
[0219] Tablets may be either film coated or enteric coated
according to methods known in the art.
[0220] Suitable compositions for oral administration include an
effective amount of a compound of the invention in the form of
tablets, lozenges, aqueous or oily suspensions, dispersible powders
or granules, emulsion, hard or soft capsules, or syrups or elixirs.
Compositions intended for oral use are prepared according to any
method known in the art for the manufacture of pharmaceutical
compositions and such compositions can contain one or more agents
selected from the group consisting of sweetening agents, flavoring
agents, coloring agents and preserving agents in order to provide
pharmaceutically elegant and palatable preparations. Tablets may
contain the active ingredient in admixture with nontoxic
pharmaceutically acceptable excipients which are suitable for the
manufacture of tablets. These excipients are, for example, inert
diluents, such as calcium carbonate, sodium carbonate, lactose,
calcium phosphate or sodium phosphate; granulating and
disintegrating agents, for example, corn starch, or alginic acid;
binding agents, for example, starch, gelatin or acacia; and
lubricating agents, for example magnesium stearate, stearic acid or
talc. The tablets are uncoated or coated by known techniques to
delay disintegration and absorption in the gastrointestinal tract
and thereby provide a sustained action over a longer period. For
example, a time delay material such as glyceryl monostearate or
glyceryl distearate can be employed. Formulations for oral use can
be presented as hard gelatin capsules wherein the active ingredient
is mixed with an inert solid diluent, for example, calcium
carbonate, calcium phosphate or kaolin, or as soft gelatin capsules
wherein the active ingredient is mixed with water or an oil medium,
for example, peanut oil, liquid paraffin or olive oil.
[0221] Certain injectable compositions are aqueous isotonic
solutions or suspensions, and suppositories are advantageously
prepared from fatty emulsions or suspensions. Said compositions may
be sterilized and/or contain adjuvants, such as preserving,
stabilizing, wetting or emulsifying agents, solution promoters,
salts for regulating the osmotic pressure and/or buffers. In
addition, they may also contain other therapeutically valuable
substances. Said compositions are prepared according to
conventional mixing, granulating or coating methods, respectively,
and contain about 0.1-75%, or contain about 1-50%, of the active
ingredient.
[0222] Suitable compositions for transdermal application include an
effective amount of a compound of the invention with a suitable
carrier. Carriers suitable for transdermal delivery include
absorbable pharmacologically acceptable solvents to assist passage
through the skin of the host. For example, transdermal devices are
in the form of a bandage comprising a backing member, a reservoir
containing the compound optionally with carriers, optionally a rate
controlling barrier to deliver the compound of the skin of the host
at a controlled and predetermined rate over a prolonged period of
time, and means to secure the device to the skin.
[0223] Suitable compositions for topical application, e.g., to the
skin and eyes, include aqueous solutions, suspensions, ointments,
creams, gels or sprayable formulations, e.g., for delivery by
aerosol or the like. Such topical delivery systems will in
particular be appropriate for dermal application, e.g., for the
treatment of skin cancer, e.g., for prophylactic use in sun creams,
lotions, sprays and the like. They are thus particularly suited for
use in topical, including cosmetic, formulations well-known in the
art. Such may contain solubilizers, stabilizers, tonicity enhancing
agents, buffers and preservatives.
[0224] As used herein a topical application may also pertain to an
inhalation or to an intranasal application. They may be
conveniently delivered in the form of a dry powder (either alone,
as a mixture, for example a dry blend with lactose, or a mixed
component particle, for example with phospholipids) from a dry
powder inhaler or an aerosol spray presentation from a pressurised
container, pump, spray, atomizer or nebuliser, with or without the
use of a suitable propellant.
[0225] The present invention further provides anhydrous
pharmaceutical compositions and dosage forms comprising the
compounds of the present invention as active ingredients, since
water may facilitate the degradation of certain compounds.
[0226] Anhydrous pharmaceutical compositions and dosage forms of
the invention can be prepared using anhydrous or low moisture
containing ingredients and low moisture or low humidity conditions.
An anhydrous pharmaceutical composition may be prepared and stored
such that its anhydrous nature is maintained. Accordingly,
anhydrous compositions are packaged using materials known to
prevent exposure to water such that they can be included in
suitable formulary kits. Examples of suitable packaging include,
but are not limited to, hermetically sealed foils, plastics, unit
dose containers (e.g., vials), blister packs, and strip packs.
[0227] The invention further provides pharmaceutical compositions
and dosage forms that comprise one or more agents that reduce the
rate by which the compound of the present invention as an active
ingredient will decompose. Such agents, which are referred to
herein as "stabilizers," include, but are not limited to,
antioxidants such as ascorbic acid, pH buffers, or salt buffers,
etc.
[0228] In accordance with the foregoing, in a further aspect, the
invention relates to an agent of the invention for use as a
medicament, for example for the treatment or prevention of a
neurological or vascular condition, disease or disorder, in which
beta-amyloid generation or aggregation plays a role, or for the
suppression of the metastasis process associated with tumor cells,
or for the treatment or prevention of loss of .beta. cell mass
and/or function. In one embodiment, the invention relates to an
agent of the invention for use in the treatment of a disease or
disorder mediated by BACE-1, BACE-2 or cathepsin D activity. In
another embodiment, the invention relates to an agent of the
invention for use in the treatment or prevention of Alzheimer's
Disease or mild cognitive impairment. In a further embodiment, the
invention relates to an agent of the invention for use in the
treatment or prevention of insulin resistance, glucose intolerance,
type 2 diabetes, obesity, hypertension, or diabetic complications.
In yet another embodiment, the invention relates to a compound of
the invention for use in the treatment of impaired glucose
tolerance or Type 2 diabetes.
[0229] In a further aspect, the invention relates to the use of an
agent of the invention as an active pharmaceutical ingredient in a
medicament, for example for the treatment or prevention of a
neurological or vascular condition, disease or disorder, in which
beta-amyloid generation or aggregation plays a role, or for the
suppression of the metastasis process associated with tumor cells,
or for the treatment or prevention of loss of .beta. cell mass
and/or function. In a further embodiment, the invention relates to
the use of an agent of the invention as an active pharmaceutical
ingredient in a medicament for the treatment or prevention of a
disease or disorder mediated by BACE-1, BACE-2 or cathepsin D
activity. In one embodiment, the invention relates to the use of an
agent of the invention as an active pharmaceutical ingredient in a
medicament for the treatment or prevention of Alzheimer's Disease
or mild cognitive impairment. In a further embodiment, the
invention relates to the use of a compound of the invention as an
active pharmaceutical ingredient in a medicament for the treatment
or prevention of insulin resistance, glucose intolerance, type 2
diabetes, obesity, hypertension, or diabetic complications. In yet
a further embodiment, the invention relates to the use of a
compound of the invention as an active pharmaceutical ingredient in
a medicament for the treatment or prevention of impaired glucose
tolerance or Type 2 diabetes.
[0230] In a further aspect, the invention relates to the use of an
agent of the invention for the manufacture of a medicament for the
treatment or prevention of a neurological or vascular condition,
disease or disorder, in which beta-amyloid generation or
aggregation plays a role, or for the suppression of the metastasis
process associated with tumor cells, or for the treatment or
prevention of loss of .beta. cell mass and/or function. In a
further embodiment, the invention relates to the use of an agent of
the invention for the manufacture of a medicament for the treatment
or prevention of a disease or disorder mediated by BACE-1, BACE-2
or cathepsin D activity. In one embodiment, the invention relates
to the use of an agent of the invention for the manufacture of a
medicament for the treatment or prevention of Alzheimer's Disease
or mild cognitive impairment. In a further embodiment, the
invention relates to the use of a compound of the invention as an
active pharmaceutical ingredient in a medicament for the treatment
or prevention of insulin resistance, glucose intolerance, type 2
diabetes, obesity, hypertension, or diabetic complications. In yet
a further embodiment, the invention relates to the use of a
compound of the invention as an active pharmaceutical ingredient in
a medicament for the treatment or prevention of impaired glucose
tolerance or Type 2 diabetes.
[0231] In a further aspect, the invention relates to a method for
the treatment or prevention of a neurological or vascular
condition, disease or disorder, in which beta-amyloid generation or
aggregation plays a role, or for the suppression of the metastasis
process associated with tumor cells, or for the treatment or
prevention of loss of .beta. cell mass and/or function, in a
subject in need of such treatment, prevention or suppression, which
method comprises administering to such subject an effective amount
of an agent of the invention. In one embodiment, the invention
relates to a method of modulating BACE-1, BACE-2 or cathepsin D
activity in a subject, wherein the method comprises administering
to the subject a therapeutically effective amount of an agent of
the invention. In another embodiment, the invention relates to a
method for the treatment or prevention of a disease mediated by
BACE-1, BACE-2 or cathepsin D activity, in a subject in need of
such treatment or prevention, which method comprises administering
to such subject an effective amount of an agent of the invention.
In yet another embodiment, the invention relates to a method for
the treatment or prevention of Alzheimer's Disease or mild
cognitive impairment, in a subject in need of such treatment or
prevention, which method comprises administering to such subject an
effective amount of an agent of the invention. In a further
embodiment, the invention relates to a method for the treatment or
prevention of insulin resistance, glucose intolerance, type 2
diabetes, obesity, hypertension, or diabetic complications, in a
subject in need of such treatment or prevention, which method
comprises administering to such subject a therapeutically effective
amount of a compound of the invention. In yet a further embodiment,
the invention relates to a method for the treatment or prevention
of impaired glucose tolerance or Type 2 diabetes, in a subject in
need of such treatment or prevention, which method comprises
administering to such subject a therapeutically effective amount of
a compound of the invention.
[0232] An agent of the invention can be administered as sole active
pharmaceutical ingredient or as a combination with at least one
other active pharmaceutical ingredient effective, e.g., in the
treatment or prevention of a neurological or vascular condition,
disease or disorder, in which beta-amyloid generation or
aggregation plays a role, or in the suppression of the metastasis
process associated with tumor cells, or in the treatment or
prevention of loss of .beta. cell mass and/or function. Such a
pharmaceutical combination may be in the form of a unit dosage
form, which unit dosage form comprises a predetermined quantity of
each of the at least two active components in association with at
least one pharmaceutically acceptable carrier or diluent.
Alternatively, the pharmaceutical combination may be in the form of
a package comprising the at least two active components separately,
e.g. a pack or dispenser-device adapted for the concomitant or
separate administration of the at least two active components, in
which these active components are separately arranged. In a further
aspect, the invention relates to such pharmaceutical
combinations.
[0233] In a further aspect, the invention therefore relates to a
combination comprising a therapeutically effective amount of an
agent of the invention and a second drug substance, for
simultaneous or sequential administration.
[0234] In one embodiment, the invention provides a product
comprising an agent of the invention and at least one other
therapeutic agent as a combined preparation for simultaneous,
separate or sequential use in therapy. In one embodiment, the
therapy is the treatment of a disease or condition mediated by
BACE-1, BACE-2 or cathepsin D activity, such as Alzheimer's
Disease, mild cognitive impairment, impaired glucose tolerance or
type 2 diabetes.
[0235] In one embodiment, the invention provides a pharmaceutical
composition comprising an agent of the invention and another
therapeutic agent(s). Optionally, the pharmaceutical composition
may comprise a pharmaceutically acceptable carrier, as described
above.
[0236] In one embodiment, the invention provides a kit comprising
two or more separate pharmaceutical compositions, at least one of
which contains an agent of the invention. In one embodiment, the
kit comprises means for separately retaining said compositions,
such as a container, divided bottle, or divided foil packet. An
example of such a kit is a blister pack, as typically used for the
packaging of tablets, capsules and the like. The kit of the
invention may be used for administering different dosage forms, for
example, oral and parenteral, for administering the separate
compositions at different dosage intervals, or for titrating the
separate compositions against one another. To assist compliance,
the kit of the invention typically comprises directions for
administration.
[0237] In the combination therapies of the invention, the agent of
the invention and the other therapeutic agent may be manufactured
and/or formulated by the same or different manufacturers. Moreover,
the compound of the invention and the other therapeutic may be
brought together into a combination therapy: (i) prior to release
of the combination product to physicians (e.g. in the case of a kit
comprising the compound of the invention and the other therapeutic
agent); (ii) by the physician themselves (or under the guidance of
the physician) shortly before administration; (iii) in the patient
themselves, e.g. during sequential administration of the compound
of the invention and the other therapeutic agent. Accordingly, the
invention provides an agent of the invention for use in the
treatment of a disease or condition mediated by BACE-1, BACE-2 or
cathepsin D activity, such as Alzheimer's Disease, impaired glucose
tolerance or type 2 diabetes, wherein the medicament is prepared
for administration with another therapeutic agent. The invention
also provides the use of another therapeutic agent for treating a
disease or condition mediated by BACE-1, BACE-2 or cathepsin D
activity, such as Alzheimer's Disease, impaired glucose tolerance
or type 2 diabetes, wherein the medicament is administered with an
agent of the invention.
[0238] The invention also provides an agent of the invention for
use in a method of treating a disease or condition mediated by
BACE-1, BACE-2 or cathepsin D activity, such as Alzheimer's
Disease, impaired glucose tolerance or type 2 diabetes, wherein the
agent of the invention is prepared for administration with another
therapeutic agent. The invention also provides another therapeutic
agent for use in a method of treating a disease or condition
mediated by BACE-1, BACE-2 or cathepsin D activity, such as
Alzheimer's Disease, impaired glucose tolerance or type 2 diabetes,
wherein the other therapeutic agent is prepared for administration
with an agent of the invention. The invention also provides an
agent of the invention for use in a method of treating a disease or
condition mediated by BACE-1, BACE-2 or cathepsin D activity, such
as Alzheimer's Disease, impaired glucose tolerance or type 2
diabetes, wherein the agent of the invention is administered with
another therapeutic agent. The invention also provides another
therapeutic agent for use in a method of treating a disease or
condition mediated by BACE-1, BACE-2 or cathepsin D activity, such
as Alzheimer's Disease, impaired glucose tolerance or type 2
diabetes, wherein the other therapeutic agent is administered with
an agent of the invention.
[0239] The invention also provides the use of an agent of the
invention for treating a disease or condition mediated by BACE-1,
BACE-2 or cathepsin D activity, such as Alzheimer's Disease,
impaired glucose tolerance or type 2 diabetes, wherein the patient
has previously (e.g. within 24 hours) been treated with another
therapeutic agent. The invention also provides the use of another
therapeutic agent for treating a disease or condition mediated by
BACE-1, BACE-2 or cathepsin D activity, such as Alzheimer's
Disease, impaired glucose tolerance or type 2 diabetes, wherein the
patient has previously (e.g. within 24 hours) been treated with an
agent of the invention.
[0240] In one embodiment, the invention relates to a compound of
the invention, or a pharmaceutically acceptable salt thereof, in
combination with another therapeutic agent wherein the other
therapeutic agent is selected from:
[0241] (a) acetylcholinesterase inhibitors, such as donepezil
(Aricept.TM.), rivastigmine (Exelon.TM.) and galantamine
(Razadyne.TM.);
[0242] (b) glutamate antagonists, such as memantine
(Namenda.TM.);
[0243] (c) antidepressant medications for low mood and
irritability, such as citalopram (Celexa.TM.) fluoxetine
(Prozac.TM.), paroxeine (Paxil.TM.), sertraline (Zoloft.TM.) and
trazodone (Desyrel.TM.);
[0244] (d) anxiolytics for anxiety, restlessness, verbally
disruptive behavior and resistance, such as lorazepam (Ativan.TM.)
and oxazepam (Serax.TM.);
[0245] (e) antipsychotic medications for hallucinations, delusions,
aggression, agitation, hostility and uncooperativeness, such as
aripiprazole (Abilify.TM.), clozapine (Clozaril.TM.), haloperidol
(Haldol.TM.), olanzapine (Zyprexa.TM.), quetiapine (Seroquel.TM.),
risperidone (Risperdal.TM.) and ziprasidone (Geodon.TM.);
[0246] (f) mood stabilizers, such as carbamazepine (Tegretol.TM.)
and divalproex (Depakote.TM.);
[0247] (g) nicotinic apha--7 agonists;
[0248] (h) mGluR5 antagonists;
[0249] (i) H3 agonists; and
[0250] (j) amyloid therapy vaccines.
[0251] Thus, in one embodiment, the invention provides a
pharmaceutical composition comprising;
[0252] i) a compound of the invention, or a pharmaceutically
acceptable salt thereof, and
[0253] ii) at least one compound selected from [0254] a)
acetylcholinesterase inhibitors, [0255] b) glutamate antagonists,
[0256] c) antidepressant medications, [0257] d) anxiolytics, [0258]
e) antipsychotic medications, [0259] (f) mood stabilizers, [0260]
(g) nicotinic apha--7 agonists, [0261] (h) mGluR5 antagonists,
[0262] (i) H3 agonists, [0263] (j) amyloid therapy vaccines, and
ii) one or more pharmaceutically acceptable carriers.
[0264] In another embodiment, the invention relates to a compound
of the invention, or a pharmaceutically acceptable salt thereof, in
combination with another therapeutic agent wherein the other
therapeutic agent is selected from:
[0265] a) antidiabetic agents, such as insulin, insulin derivatives
and mimetics; insulin secretagogues such as the sulfonylureas,
e.g., Glipizide, glyburide and Amaryl; insulinotropic sulfonylurea
receptor ligands such as meglitinides, e.g., nateglinide and
repaglinide; protein tyrosine phosphatase-1B (PTP-1B) inhibitors
such as PTP-112; GSK3 (glycogen synthase kinase-3) inhibitors such
as SB-517955, SB-4195052, SB-216763, NN-57-05441 and NN-57-05445;
RXR ligands such as GW-0791 and AGN-194204; sodium-dependent
glucose cotransporter inhibitors such as T-1095; glycogen
phosphorylase A inhibitors such as BAY R3401; biguanides such as
metformin; alpha-glucosidase inhibitors such as acarbose; GLP-1
(glucagon like peptide-1), GLP-1 analogs such as Exendin-4 and
GLP-1 mimetics; and DPPIV (dipeptidyl peptidase IV) inhibitors such
as vildagliptin;
[0266] b) hypolipidemic agents such as 3-hydroxy-3-methyl-glutaryl
coenzyme A (HMG-CoA) reductase inhibitors, e.g., lovastatin,
pitavastatin, simvastatin, pravastatin, cerivastatin, mevastatin,
velostatin, fluvastatin, dalvastatin, atorvastatin, rosuvastatin
and rivastatin; squalene synthase inhibitors; FXR (farnesoid X
receptor) and LXR (liver X receptor) ligands; cholestyramine;
fibrates; nicotinic acid bile acid binding resins such as
cholestyramine; fibrates; nicotinic acid and other GPR109 agonists;
cholesterol absorption inhibitors such as ezetimibe; CETP
inhibitors (cholesterol-ester-transfer-protein inhibitors), and
aspirin;
[0267] c) anti-obesity agents such as orlistat, sibutramine and
Cannabinoid Receptor 1 (CB1) antagonists e.g. rimonabant; and
[0268] d) anti-hypertensive agents, e.g., loop diuretics such as
ethacrynic acid, furosemide and torsemide; angiotensin converting
enzyme (ACE) inhibitors such as benazepril, captopril, enalapril,
fosinopril, lisinopril, moexipril, perinodopril, quinapril,
ramipril and trandolapril; inhibitors of the Na-K-ATPase membrane
pump such as digoxin; neutralendopeptidase (NEP) inhibitors;
ACE/NEP inhibitors such as omapatrilat, sampatrilat and fasidotril;
angiotensin II antagonists such as candesartan, eprosartan,
irbesartan, losartan, telmisartan and valsartan, in particular
valsartan; renin inhibitors such as ditekiren, zankiren,
terlakiren, aliskiren, RO 66-1132 and RO-66-1168; .beta.-adrenergic
receptor blockers such as acebutolol, atenolol, betaxolol,
bisoprolol, metoprolol, nadolol, propranolol, sotalol and timolol;
inotropic agents such as digoxin, dobutamine and milrinone; calcium
channel blockers such as amlodipine, bepridil, diltiazem,
felodipine, nicardipine, nimodipine, nifedipine, nisoldipine and
verapamil; aldosterone receptor antagonists; and aldosterone
synthase inhibitors.
[0269] e) agonists of peroxisome proliferator-activator receptors,
such as fenofibrate, pioglitazone, rosiglitazone, tesaglitazar,
BMS-298585, L-796449, the compounds specifically described in the
patent application WO 2004/103995 i.e. compounds of examples 1 to
35 or compounds specifically listed in claim 21, or the compounds
specifically described in the patent application WO 03/043985 i.e.
compounds of examples 1 to 7 or compounds specifically listed in
claim 19 and especially
(R)-1-{4-[5-methyl-2-(4-trifluoromethyl-phenyl)-oxazol-4-ylmethoxy]-benze-
nesulfonyl}-2,3-dihydro-1H-indole-2-carboxylic or a salt
thereof.
[0270] Thus, in one embodiment, the invention provides a
pharmaceutical composition comprising;
[0271] i) a compound of the invention, or a pharmaceutically
acceptable salt thereof, and
[0272] ii) at least one compound selected from [0273] a)
antidiabetic agents, [0274] b) hypolipidemic agents, [0275] c)
anti-obesity agents, [0276] d) anti-hypertensive agents, [0277] e)
agonists of peroxisome proliferator-activator receptors, and
[0278] ii) one or more pharmaceutically acceptable carriers.
[0279] Other specific anti-diabetic compounds are described by
Patel Mona in Expert Opin Investig Drugs, 2003, 12(4), 623-633, in
the FIGS. 1 to 7.
[0280] The structure of the therapeutic agents identified by code
numbers, generic or trade names may be taken from the actual
edition of the standard compendium "The Merck Index" or from
databases, e.g., Patents International (e.g. IMS World
Publications).
EXAMPLES
NMR Methods
[0281] Proton spectra are recorded on a Bruker 400 MHz ultrashield
spectrometer unless otherwise noted. Chemical shifts are reported
in ppm relative to methanol (.delta. 3.31), dimethyl sulfoxide
(.delta. 2.50), or chloroform (.delta. 7.29). A small amount of the
dry sample (1-5 mg) is dissolved in an appropriate deuterated
solvent (0.7 mL). The shimming is automated and the spectra
obtained in accordance with normal procedure.
General Chromatography Conditions
UPLC Method H1 (Rt.sub.H1):
[0282] HPLC-column dimensions: 2.1.times.50 mm [0283] HPLC-column
type: Acquity UPLC HSS T3, 1.8 .mu.m [0284] HPLC-eluent: A)
water+0.05 Vol.-% formic acid+3.75 mM ammonium acetate B) ACN+0.04
Vol.-% formic acid [0285] HPLC-gradient: 2-98% B in 1.4 min, 98% B
0.75 min, flow=1.2 ml/min [0286] HPLC-column temperature:
50.degree. C.
UPLC Method H2 (Rt.sub.H2):
[0286] [0287] HPLC-column dimensions: 2.1.times.50 mm [0288]
HPLC-column type: Acquity UPLC HSS T3, 1.8 .mu.m [0289]
HPLC-eluent: A) water+0.05 Vol.-% formic acid+3.75 mM ammonium
acetate B) ACN+0.04 Vol.-% formic acid [0290] HPLC-gradient: 5-98%
B in 1.4 min, 98% B 0.4 min, flow=1.0 ml/min [0291] HPLC-column
temperature: 60.degree. C.
LCMS Method H3 (Rt.sub.H3):
[0291] [0292] HPLC-column dimensions: 4.0.times.20 mm [0293]
HPLC-column type: Mercury MS Synergi, 2 .mu.m [0294] HPLC-eluent:
A) water+0.1 Vol.-% formic acid, B) ACN [0295] HPLC-gradient: 0.5
min 70% B, 70-100% B in 1 min, 0.9 min 100% B, flow=2.0 ml/min
[0296] HPLC-column temperature: 30.degree. C.
LCMS Method H4 (Rt.sub.H4):
[0296] [0297] HPLC-column dimensions: 2.1.times.30 mm [0298]
HPLC-column type: Ascentis Express C18, 2.8 .mu.m [0299]
HPLC-eluent A) water+0.05 Vol.-% formic acid+3.75 mM ammonium
acetate B) ACN+0.04 Vol.-% formic acid [0300] HPLC-gradient: 2-98%
B in 1.4 min, 0.75 min 98% B, flow=1.2 ml/min [0301] HPLC-column
temperature: 50.degree. C.
HPLC Method H5 (Rt.sub.H5):
[0301] [0302] HPLC-column dimensions: 3.0.times.30 mm [0303]
HPLC-column type: Zorbax SB-C18, 1.8 .mu.m [0304] HPLC-eluent: A)
water+0.05 Vol.-% TFA; B) ACN+0.05 Vol.-% TFA [0305] HPLC-gradient:
0-100% B in 3.25 min, 0.75 min 100% B, flow=0.7 ml/min [0306]
HPLC-column temperature: 35.degree. C.
UPLC Method H6 (Rt.sub.H6):
[0306] [0307] HPLC-column dimensions: 2.1.times.50 mm [0308]
HPLC-column type: Acquity UPLC HSS T3, 1.8 .mu.m [0309]
HPLC-eluent: A) water+0.1 Vol.-% TFA; B) ACN+0.1 Vol.-% TFA [0310]
HPLC-gradient: 10-95% B in 1.5 min, flow=1.0 ml/min
HPLC Method H7 (Rt.sub.H7):
[0310] [0311] HPLC-column dimensions: 3.0.times.30 mm [0312]
HPLC-column type: Zorbax SB-C18, 1.8 .mu.m [0313] HPLC-eluent: A)
water+0.05 Vol.-% TFA; B) ACN+0.05 Vol.-% TFA [0314] HPLC-gradient:
30-100% B in 3.25 min, 0.75 min 100% B, flow=0.7 ml/min [0315]
HPLC-column temperature: 35.degree. C.
HPLC Method H8 (Rt.sub.H8):
[0315] [0316] HPLC-column dimensions: 3.0.times.30 mm [0317]
HPLC-column type: Zorbax SB-C18, 1.8 .mu.m [0318] HPLC-eluent: A)
water+0.05 Vol.-% TFA; B) ACN+0.05 Vol.-% TFA [0319] HPLC-gradient:
10-100% B in 3.25 min, 0.75 min 100% B, flow=0.7 ml/min [0320]
HPLC-column temperature: 35.degree. C.
Abbreviations
[0321] ACN acetonitrile AcOH acetic acid aq. aqueous Boc.sub.2O
tert-butyl dicarbonate BuLi butyl lithium CSA campher sulfonic acid
DAST diethylaminosulfur trifluoride dba dibenzylideneacetone DCM
dichloromethane DEAD diethyl azodicarboxylate DIAD diisopropyl
azodicarboxylate DIPEA diisopropylethylamine DMA dimethylacetamide
DMF dimethylformamide DMSO dimethylsulfoxide DMTr
4,4'-dimethoxytrityl DPPF 1,1'-bis-diphenylphosphino-ferrocene EDC
1-(3-dimethylaminopropyl)-3-ethylcarbodiimide Et.sub.3N
triethylamine EtOAc ethyl acetate EtOH ethanol h hour(s) hex hexane
HOAt 1-hydroxy-7-aza-benztriazole HPLC high performance liquid
chromatography LCMS liquid chromatography with mass spectrometry
LDA lithium diisopropylamide mCPBA 3-chloroperbenzoic acid MeOH
methanol min minute(s) MS mass spectrometry NEt.sub.3 triethylamine
NMR nuclear magnetic resonance spectrometry R.sub.f retention
factor (TLC) RP reverse phase Rt retention time rt room temperature
sat. saturated TBME tert-butyl-methyl-ether TFA trifluoroacetic
acid THF tetrahydrofuran TLC thin layer chromatography Xantphos
4,5-bis(diphenylphosphino)-9,9-dimethylxanthene
Example 1
5-Cyano-3-methyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide
##STR00024##
[0322] a) 2-Bromo-5-fluoro-4-triethylsilanylpyridine
[0323] To a solution of diisopropylamine (25.3 g, 250 mmol) in THF
(400 ml) was added n-BuLi (100 ml, 2.5 mol/L in hexanes) below
-50.degree. C. A solution of 2-bromo-5-fluoropyridine (41.9 g, 238
mmol) in THF (60 ml) was added to the LDA-solution at -78.degree.
C. in a dropwise manner below -63.degree. C. After 60 minutes at
-78.degree. C. triethylchlorosilane (44 ml, 262 mmol) was added in
a fast manner keeping the temperature below -50.degree. C. The
cooling bath was removed and the reaction mixture was allowed to
reach -20.degree. C. The reaction mixture was poured on a mixture
of 1M aq. HCl (250 ml) and aq. NH.sub.4Cl (10%). Tert.-butyl methyl
ether was added and the layers were separated. The organic phase
was washed with brine, dried over magnesium sulfate, filtered and
evaporated to give a yellow liquid. Distillation (bp.
99-101.degree. C., 0.5 mmHg). afforded the title compound as a
slightly yellow liquid: 66.26 g (96% yield).
[0324] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 8.17 (s, 1H),
7.42 (d, 1H), 1.01-0.97 (m, 9H), 0.92-0.87 (m, 6H).
b) 1-(6-Bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-ethanone
[0325] To a solution of diisopropylamine (25.4 g, 251 mmol) in THF
(500 ml) was added n-BuLi (100 ml, 2.5 mol/L in hexanes) below
-50.degree. C. A solution of
2-bromo-5-fluoro-4-triethylsilanyl-pyridine (56.04 g, 193 mmol) in
THF (60 ml) was added to the LDA-solution at -78.degree. C. in a
dropwise manner below -65.degree. C. After 70 minutes at
-78.degree. C. DMA (23.51 ml, 251 mmol) was added dropwise in a
fast manner to the deep red solution keeping the temperature below
-57.degree. C. After 15 minutes the cooling bath was removed and
the reaction mixture was allowed to reach -40.degree. C. The cold
reaction mixture was poured on a mixture of 2M aq. HCl (250
ml)/water (200 ml)/brine (100 ml). Tert.-butyl methyl ether was
added and the layers were separated. The organic phase was washed
twice with brine, dried over magnesium sulfate, filtered and
evaporated to give a yellow oil. The crude product (64.76 g) was
chromatographed over silica gel (hexane/TBME) to give the title
compound as a yellow liquid: 58.3 g (91% yield).
[0326] TLC (hexane/TBME 99:1): R.sub.f=0.25;
[0327] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.55 (d, 1H),
2.67 (3, 3H), 0.98-0.93 (m, 9H), 0.91-0.85 (m, 6H).
c) (R)-2-Methyl-propane-2-sulfinic
acid[1-(6-bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-eth-(E)-ylidene]-
-amide
[0328] A mixture of titantetraethoxide (4.26 g, 18.69 mmol),
(R)-tert.-butylsulfinamide (1.246 g, 10.28 mmol) and
1-(6-bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-ethanone (3.45
g, 9.34 mmol, 90% pure) in THF (25 ml) was refluxed under a
nitrogen atmosphere for 6 hours. The cold reaction mixture was
poured onto icecold brine (200 ml) with gentle stirring. The
precipitate was filtered through a pad of hyflo and and washed with
ethyl acetate. The filtrate was diluted with ethyl acetate and
washed with brine, dried over sodium sulfate, filtered and
evaporated. The crude yellow oil (4.55 g) was chromatographed over
silica gel (cyclohexane/ethyl acetate 94:6) to give the title
compound as a yellow oil. 3.35 g (82% yield).
[0329] TLC (cyclohexane/ethyl acetate 5:1): R.sub.f=0.50;
[0330] HPLC: Rt.sub.H1=1.56 min; ESIMS: 435, 437 [(M+H).sup.+,
1Br];
[0331] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.48 (d, 1H),
2.28 (s, 3H), 1.34 (s, 9H), 1.01-0.98 (m, 9H), 0.92-0.89 (m,
6H).
d)
(R)-3-(6-Bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-2,2-difluoro-3--
((R)-2-methyl-propane-2-sulfinylamino)-butyric acid ethyl ester
[0332] To a suspension of zinc (466 mg, 7.12 mmol) and copper(I)
chloride (34 mg, 0.344 mmol) in dry THF (20 ml) were added 3 drops
of trimethylchlorosilane under nitrogen to activate the zinc. After
10 minutes ethyl 2-bromo-2,2-difluoroacetate (1.398 g, 6.89 mmol)
was added slowly by syringe over a period of 10 minutes at
25.degree. C. (slightly exothermic). The reaction mixture was kept
in an ultrasound bath for 45 minutes. This black fine suspension
was added dropwise to a solution of (R)-2-methyl-propane-2-sulfinic
acid
[1-(6-bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-eth-(E)-ylidene]-ami-
de) (1 g, 2.296 mmol) in dry THF (10 ml) at rt under inert
atmosphere. After 4 h at rt the reaction mixture was added to a
cold aq. ammonium chloride solution (5%) and was diluted with ethyl
acetate. The organic phase was washed with aq. citric acid (5%
solution), water, sat. sodium bicarbonate solution and brine, dried
over sodium sulfate, filtered and concentrated. The crude brownish
oil (1.5 g) was chromatographed over silica gel (cyclohexane/ethyl
acetate 83:17) to give the title compound as a light yellow oil.
984 mg (77% yield).
[0333] TLC (cyclohexane/ethyl acetate 2:1): R.sub.f=0.46;
[0334] HPLC: Rt.sub.H1=1.54 min; ESIMS: 559, 561 [(M+H).sup.+,
1Br];
[0335] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.40 (d, 1H),
5.48 (s, NH), 4.38 (q, 2H), 2.07 (s, 3H), 1.26 (s, 9H), 1.00-0.96
(m, 9H), 0.90-0.86 (m, 6H).
[0336] Minor diastereoisomer R.sub.f=0.64 (2:1 cyclohexane:ethyl
acetate).
e)
(R)-3-(6-Bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-3-((R)-2-methyl-prop-
ane-2-sulfinylamino)-butyric acid ethyl ester
[0337] Freshly ground KF (195 mg, 3.36 mmol) was added to a
solution of
(R)-3-(6-bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-2,2-difluoro-3-((-
R)-2-methyl-propane-2-sulfinylamino)-butyric acid ethyl ester (940
mg, 1.68 mmol) and acetic acid (0.192 ml, 3.36 mmol) in THF (7 ml).
DMF (7 ml) was added and the suspension was stirred at rt. After 2
h the reaction mixture was diluted with ethyl acetate and washed
with sat. sodium bicarbonate solution and brine, dried over sodium
sulfate, filtered and evaporated. The crude product (733 mg) was
chromatographed over silica gel (cyclohexane/ethyl acetate 7:3) to
give the title compound as a slightly yellow oil. 664 mg (88%
yield).
[0338] TLC (cyclohexane/ethyl acetate 1:1): R.sub.f=0.38;
[0339] HPLC: Rt.sub.H1=1.08 min; ESIMS: 445, 447 [(M+H).sup.+,
1Br];
[0340] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.51-7.46 (dd,
1H), 7.35 (t, 1H), 5.38 (br. s, 1H, NH), 4.37 (q, 2H), 2.07 (s,
3H), 1.39 (t, 3H), 1.26 (s, 9H).
f) (R)-2-Methyl-propane-2-sulfinic acid
[(R)-1-(6-bromo-3-fluoro-pyridin-2-yl)-2,2,difluoro-3-hydroxy-1-methyl-pr-
opyl]amide
[0341] To a solution of
(R)-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-3-((R)-2-methyl-propan-
e-2-sulfinylamino)-butyric acid ethyl ester (513 mg, 1.15 mmol) in
THF (11.5 ml) was added lithiumborohydride (52.8 mg, 2.30 mmol).
The slightly exothermic reaction was stirred for 2.5 h at room
temperature. Crushed ice was added and the reaction mixture was
diluted with ethyl acetate. The organic phase was washed with water
and brine, dried over sodium sulfate, filtered and evaporated; 465
mg (quantitative yield) slightly yellow resin which was used
without purification in the next step.
[0342] TLC (toluene/ethyl acetate 7:3): R.sub.f=0.16;
[0343] HPLC: Rt.sub.H1=0.93 min; ESIMS: 403, 405 [(M+H).sup.+,
1Br];
[0344] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.52 (dd, 1H),
7.38 (dd, 1H), 5.84 (s broad, 1H), 4.32 (dd, 1H), 4.02 (m, 1H),
3.81 (m, 1H), 2.05 (s, 3H), 1.31 (s, 9H).
g)
(R)-3-Amino-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-butan-1-ol
[0345] To a solution of (R)-2-methyl-propane-2-sulfinic acid
[(R)-1-(6-bromo-3-fluoro-pyridin-2-yl)-2,2,difluoro-3-hydroxy-1-methyl-pr-
opyl]amide (1.33 g, 3.30 mmol) in dioxane (26.6 ml) was added
HCl/dioxane 4N (3.3 ml, 13.19 mmol). The reaction mixture was
stirred for 21 hours at room temperature. The solvent was
evaporated and to the residue was added ethyl acetate and crushed
ice. The organic phase was extracted with water and was made
alkaline with solid potassium carbonate. The aqueous phase was
extracted with ethyl acetate, dried over sodium sulfate, filtered
and evaporated. 930 mg colourless solid (94% yield).
[0346] TLC (toluene/ethyl acetate 7:3): R.sub.f=0.25;
[0347] HPLC: Rt.sub.H1=0.44 min; ESIMS: 299, 301 [(M+H).sup.+,
1Br];
[0348] .sup.1H-NMR (400 MHz, DMSO-D.sub.6): .delta. 7.73 (m, 2H,
Ar), 7.29 (broad s, 1H), 6.69 (broad s, 1H), 5.30 (t, 1H), 3.79 (m,
2H), 1.57 (d, 3H).
h)
(R)-4-(6-Bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydro-
-4H-[1,3]oxazine-2-ylamine
[0349] A solution of
(R)-3-amino-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-butan-1-ol
(150 mg, 0.49 mmol) and bromocyan (106 mg, 1 mmol) in ethanol (5
ml) was heated for 19 h at 85.degree. C. in a capped microwave
vial. The solvent was evaporated and the residue was dissolved in
ethyl acetate. The organic phase was washed with aq. ammonia, water
and brine, dried over sodium sulfate, filtered and evaporated. The
crude product (136 mg) was chromatographed over silica
(toluene/ethyl acetate 1:1) to afford recovered starting material
(27 mg) and the title compound: 64 mg (40% yield).
[0350] TLC (toluene/ethyl acetate 1:1): R.sub.f=0.17;
[0351] HPLC: Rt.sub.H1=0.56 min; ESIMS: 324, 326 [(M+H).sup.+,
1Br];
[0352] .sup.1H-NMR (400 MHz, DMSO-D.sub.6): .delta. 7.69 (m, 2H),
5.82 (broad s, 2H), 4.36 (m, 1H), 4.17 (m, 1H), 1.63 (s, 3H).
i)
[(R)-4-(6-Bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydr-
o-4H-[1,3]oxazine-2-yl]-carbamic acid tert-butyl ester
[0353] A solution of
(R)-4-(6-bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydro-4-
H-[1,3]oxazine-2-ylamine (60 mg, 0.185 mmol), Boc-anhydride (42.3
mg, 0.194 mmol) and Hunig's base (64.7 .mu.l, 0.37 mmol) in
dichloromethane (1.9 ml) was stirred at rt for 3 days. The reaction
mixture was diluted with ethyl acetate, washed with as. Bicarbonate
solution, water and brine, dried over sodium sulfate, filtered and
evaporated. 76 mg (85% yield).
[0354] TLC (toluene/ethyl acetate 7:3): R.sub.f=0.38;
[0355] HPLC: Rt.sub.H1=1.08 min; ESIMS: 424, 426 [(M+H).sup.+,
1Br];
[0356] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.58-7.30 (m, 2H,
Ar), 4.40-4.30 (m, 2H), 1.90 (broad s, 3H), 1.52 (s, 9H).
j)
((R)-4-{6-[(5-Cyano-3-methyl-pyridine-2-carbonyl)-amino]-3-fluoro-pyrid-
in-2-yl}-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-2-yl)-carbamic
acid tert-butyl ester
[0357] A degassed mixture of
[(R)-4-(6-bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydro--
4H-[1,3]oxazine-2-yl]-carbamic acid tert-butyl ester (70 mg, 0.145
mmol), 5-cyano-3-methyl-pyridine-2-carboxylic acid amide (25.7 mg,
0.160 mmol), Xantphos (30.2 mg, 0.052 mmol), caesium carbonate
(67.6 mg, 0.203 mmol) and Pd.sub.2(dba).sub.3 (16.45 mg, 0.017
mmol) was heated under argon in dioxane (2.9 ml) at 60.degree. C.
for 5 hours. The reaction mixture (grey-brown suspension) was
diluted with ethyl acetate and aq. bicarbonate solution and was
then filtered. The filtrate was washed with water and brine, dried
over sodium sulfate, filtered and evaporated. 166 mg brown solid.
The crude product was chromatographed over silica gel
(toluene/ethyl acetate 7:3) to give the title compound as a white
solid. 28 mg (38% yield).
[0358] TLC (toluene/ethyl acetate 7:3): R.sub.f=0.25;
[0359] HPLC: Rt.sub.H1=1.18 min; ESIMS: 505 [(M+H).sup.+];
[0360] 1H-NMR (400 MHz, CDCl.sub.3): .delta. 10.7 (broad s, 1H),
10.49 (broad s, 1H), 8.77 (d, 1H), 8.49 (broad d, 1H), 7.99 (d,
1H), 7.6 (broad t, 1H), 4.49-4.30 (m, 2H), 2.88 (s, 3H), 1.92
(broad s, 3H), 1.55 (s, 9H).
k) 5-Cyano-3-methyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide
[0361] A solution of
((R)-4-{6-[(5-cyano-3-methyl-pyridine-2-carbonyl)-amino]-3-fluoro-pyridin-
-2-yl}-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-2-yl)-carbamic
acid tert-butyl ester (26 mg, 0.052 mmol) and TFA (200 .mu.l, 2.6
mmol) in dichloromethane (1.3 ml) was stirred at rt for 5 hours.
The reaction mixture was evaporated and the residue diluted with
aq. ammonia and ethyl acetate, washed with water and brine, dried
over sodium sulfate, filtered and evaporated. 24 mg yellowish
solid. Trituration with cyclohexane afforded the title compound as
a slightly yellow solid. 17 mg (80% yield).
[0362] HPLC: Rt.sub.H1=0.72 min; ESIMS: 405 [(M+H).sup.+];
[0363] .sup.1H-NMR (400 MHz, DMSO-D.sub.6): .delta. 10.71 (broad s,
1H, NH), 9.01 (broad s, 1H), 8.43 (broad s, 1H), 8.19 (broad d,
1H), 7.76 (t, 1H), 5.77 (broad s, 2H, NH.sub.2), 4.32 (m, 2H), 2.61
(s, 3H), 1.67 (broad s, 3H).
Example 2
[0364] The compound listed in Table 1 was prepared by a procedure
analogous to that used in Example 1.
TABLE-US-00003 TABLE 2 MS [m/z; Example Compound .sup.1H-NMR
(.delta.; CDCl.sub.3) (M + 1).sup.+] 2 ##STR00025## 10.15 (br s,
1H), 8.85 (d, 1H), 8.39 (dd, 1H), 8.21 (d, 1H), 7.53 (dd, 1H),
4.22-4.14 (m, 2H), 1.84 (t, 3H) LCMS: Rt.sub.H1 = 0.67 min. [M + 1]
= 425.0, 427.0 3-Chloro-5-cyano-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-
methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-
5-fluoro-pyridin-2-yl]-amide
Example 3
3-Chloro-5-cyano-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4,6,6-trimethyl-5,6-dihydro-4H-[1,3]oxazin-4-
-yl)-5-fluoro-pyridin-2-yl]-amide
##STR00026##
[0365] a) (R)-2-Methyl-propane-2-sulfinic acid
[(R)-1-(6-bromo-3-fluoro-pyridin-2-yl)-2,2,difluoro-3-hydroxy-1,3-dimethy-
l-butyl]-amide
[0366] To methylmagnesium chloride 3M in THF (38.3 ml, 115 mmol)
was added a solution of
(R)-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-3-((R)-2-methyl-propan-
e-2-sulfinylamino)-butyric acid ethyl ester (5.12 g, 11.5 mmol,
example 1e)) in THF (102 ml) at rt. After 2 hr stirring the
reaction was quenched with addition of an aqueous ammonium chloride
solution. The mixture was diluted with ethyl acetate and washed
with water and brine, dried over sodium sulfate, filtered and
evaporated. The crude product (4.78 g) was chromatographed over
silica gel (cyclohexane/ethyl acetate 6:4) to give the title
compound as a colourless solid. 2.97 g (59.9% yield).
[0367] TLC (cyclohexane/ethyl acetate 6:4, silica gel, UV 254):
R.sub.f=0.32;
[0368] LC-MS: Rt.sub.H1=1.09 min; (100% pure; ESI+-MS: m/z 431
[(M+H).sup.+]);
[0369] .sup.1H-NMR (400 MHz, DMSO-d.sub.6) .delta.=7.83-7.70 (m,
2H), 6.10 (s, 1H), 5.48 (s, 1H), 1.93 (s, 3H), 1.23 (s, 3H), 1.18
(s, 9H), 1.07 (s, 3H).
b)
(R)-4-(6-Bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4,6,6-trimethyl-5,6--
dihydro-4H-[1,3]oxazin-2-ylamine
[0370] A solution of (R)-2-methyl-propane-2-sulfinic acid
[(R)-1-(6-bromo-3-fluoro-pyridin-2-yl)-2,2,difluoro-3-hydroxy-1,3-dimethy-
l-butyl]-amide (2.95 g, 6.84 mmol) and cyanogen bromide (2.24 g,
20.52 mmol) in dry ethanol (68 ml) was sealed with a glass stopper
and heated at 85.degree. C. for 9 hr. The reaction solution was
evaporated in vacuo and the crude product was taken up with ethyl
acetate and 2M aq. ammonia. The organic phase was washed with water
and brine, dried over sodium sulfate, filtered and evaporated. The
crude product (2.74 g) was chromatographed over silica gel
(toluene/ethyl acetate 6:4) to give the title compound as a
colourless solid. 1.19 g (48.9% yield).
[0371] LC-MS: Rt.sub.H1=67 min; (99% pure; ESI+-MS: m/z 352
[(M+H).sup.+], 354);
[0372] .sup.1H-NMR (400 MHz, DMSO-d.sub.6) .delta.=7.72-7.59 (m,
2H), 5.83 (br. s, 2H), 1.67 (d, J=4.0 Hz, 3H), 1.48 (s, 3H), 1.27
(d, J=2.0 Hz, 3H).
c)
[Bis-(4-methoxy-phenyl)-phenyl-methyl]-[(R)-4-(6-bromo-3-fluoro-pyridin-
-2-yl)-5,5-difluoro-4,6,6-trimethyl-5,6-dihydro-4H-[1,3]oxazin-2-yl]-amine
[0373] To a solution of
(R)-4-(6-bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4,6,6-trimethyl-5,6-di-
hydro-4H-[1,3]oxazin-2-ylamine (106 mg, 0.301 mmol) and
triethylamine (60.9 mg, 0.602 mmol) in dichloromethane (3 ml) was
added solid 4,4'-dimethoxytrityl chloride (112 mg, 0.331 mmol)
under argon atmosphere. The green solution was stirred at rt for 2
hrs and was then evaporated in vacuo. The crude product was taken
up with ethyl acetate and washed with aqueous sodium bicarbonate
solution, water and brine. The organic phase was dried over sodium
sulfate, filtered and evaporated. Filtration over silica gel (4.4
g, toluene/ethyl acetate 6:4) afforded the title compound as a
blue-gray foam (202 mg, 96%).
[0374] TLC (toluene/ethyl acetate 6:4, silica gel, UV 254):
R.sub.f=0.60;
[0375] LC-MS: Rt.sub.H1=1.22 min; (94% pure; ESI+-MS: m/z 654
[(M+H).sup.+]; 656);
[0376] .sup.1H-NMR (400 MHz, DMSO-d.sub.6) .delta.=7.72-7.61 (m,
2H), 7.32-7.13 (m, 9H), 6.84-6.77 (m, 4H), 6.71 (br. s, 1H), 3.71
(s, 6H), 1.16 (br. s, 3H), 1.12 (br. s, 3H), 1.07 (br. s, 3H).
d) 3-Chloro-5-cyano-pyridine-2-carboxylic acid
[6-((R)-2-{[bis-(4-methoxy-phenyl)-phenyl-methyl]-amino}-5,5-difluoro-4,6-
,6-trimethyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]-amide
[0377] A degassed mixture of
[bis-(4-methoxy-phenyl)-phenyl-methyl]-[(R)-4-(6-bromo-3-fluoro-pyridin-2-
-yl)-5,5-difluoro-4,6,6-trimethyl-5,6-dihydro-4H-[1,3]oxazin-2-yl]-amine
(196 mg, 0.299 mmol), 5-cyano-3-methyl-pyridine-2-carboxylic acid
amide (59.8 mg, 0.329 mmol), Xantphos (62.4 mg, 0.108 mmol),
caesium carbonate (139 mg, 0.419 mmol) and Pd.sub.2(dba).sub.3
(33.9 mg, 0.036 mmol) was heated under argon in dioxane (6 ml) at
60.degree. C. for 20 hours. The reaction mixture was diluted with
ethyl acetate and aq. bicarbonate solution and was then filtered
through hyflo. The filtrate was washed with water and brine, dried
over sodium sulfate, filtered and evaporated to give 226 mg
yellowish foam. The crude product was chromatographed over silica
gel (toluene/ethyl acetate 8:2) to give the title compound as a
light yellow foam. 92 mg (38.6% yield).
[0378] LC-MS: Rt.sub.H1=1.20 min (95% pure; ESI+-MS: 755,
[(M+H).sup.+]; 756, 757, 758);
[0379] .sup.1H-NMR (400 MHz, CDCl3): .delta. 10.24 (br. s, 1 NH),
8.74 (br. d, 1H), 8.36 (dd, 1H), 8.21 (d, J=1.8 Hz, 1H), 7.50 (dd,
1H), 7.42-6.79 (m, 13H+1NH), 3.79 (s, 6H), 1.60 (br. s, 3H), 0.89
(br. s, 3H), 0.78 (br. s, 3H).
e) 3-Chloro-5-cyano-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4,6,6-trimethyl-5,6-dihydro-4H-[1,3]oxazin-4-
-yl)-5-fluoro-pyridin-2-yl]-amide
[0380] A solution of 3-chloro-5-cyano-pyridine-2-carboxylic acid
[6-((R)-2-{[bis-(4-methoxy-phenyl)-phenyl-methyl]-amino}-5,5-difluoro-4,6-
,6-trimethyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]-amide
(85 mg, 0.113 mmol), TFA (572 .mu.l, 7.43 mmol) and triethylsilane
(54 .mu.l, 0.338 mmol) in dichloromethane (1.1 ml) was stirred at
rt for 24 hours. The reaction mixture was evaporated and the
residue diluted with ethyl acetate, washed with water and brine,
dried over sodium sulfate, filtered and evaporated to give 119 mg
brown-yellowish resin. The product was chromatographed over silica
gel (RediSep 12 g, conditioned with ethyl acetate/methanol 95:5 and
eluted with ethyl acetate) to give the title compound as a light
yellow solid. 38 mg (74.6% yield).
[0381] TLC (ethyl acetate/methanol 95:5, silica gel, UV 254):
R.sub.f=0.29;
[0382] LC-MS: Rt.sub.H1=0.76 min (100% pure; ESI+-MS: 453,
[(M+H).sup.+], 455);
[0383] .sup.1H-NMR (400 MHz, CDCl3): .delta. 12.66 (very br. s, 1
NH), 12.03 (br. s, 1 NH), 10.29 (br. s, 1 NH), 8.87 (d, J=1.8 Hz,
1H), 8.49 (dd, 1H), 8.18 (d, J=1.8 Hz, 1H), 7.62 (dd, 1H), 5.74
(br. s, 1 NH), 2.01 (d, J=2.3 Hz, 3H), 1.74 (s, 3H), 1.44 (d, J=2.3
Hz, 3H).
Example 4
5-Cyano-3-methyl-pyridine-2-carboxylic acid
{6-[(R)-2-amino-5,5-difluoro-4-(2-methoxy-ethyl)-5,6-dihydro-4H-[1,3]oxaz-
in-4-yl]-5-fluoro-pyridin-2-yl}-amide
##STR00027##
[0384] a)
1-(6-Bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-3-methoxy-pr-
opan-1-one
[0385] To a solution of
1-(6-bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-ethanone (11.6
g, 33.9 mmol, example 1, step b) in dichloromethane (50 ml) was
added Hunigs-base (6.21 ml, 35.6 mmol) at 0.degree. C. followed by
TMS-triflate (6.43 ml, 35.52 mmol, 1.05 eq.) under nitrogen. The
reaction mixture was stirred at 0.degree. C. for 40 minutes.
Dimethoxymethane (2.71 g, 35.6 mmol) and 2,6-di-tert-butylpyridine
(0.648 g, 3.39 mmol) was added drop wise at 0.degree. C.
TMS-triflate (0.61 ml, 3.39 mmol) was then added to the reaction
mixture. After 30 min the cooling bath was removed and stirring was
continued at rt over night (18 h). The reaction mixture was poured
onto cold brine, diluted with ethyl acetate and the organic phase
was washed thoroughly with 10% NaHSO.sub.4 solution, sat. sodium
bicarbonate solution (saturated with NaCl) and brine, dried over
sodium sulfate, filtered and evaporated. The crude product (13.52
g) was chromatographed over silica gel (320 g, cyclohexane/ethyl
acetate 95:5) to give the title compound as a yellow liquid: 9.18 g
(72% yield).
[0386] TLC (cyclohexane/ethyl acetate 5:1): R.sub.f=0.61;
[0387] LC-MS: Rt.sub.H1=1.43 min (100% pure; ESI+-MS: 376,
[(M+H).sup.+], 378);
[0388] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.58 (d, J=2.9
Hz, 1H), 3.83 (t, J=6.2 Hz, 2H), 3.41 (t, J=6.2 Hz, 2H), 3.39 (s,
3H), 1.06-0.82 (m, 15H).
b) (S)-2-Methyl-propane-2-sulfinic acid
[1-(6-bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-3-methoxy-prop-(E)-y-
lidene]-amide
[0389] A mixture of titantetraethoxide (11.03 g, 48.4 mmol),
(S)-tert.-butylsulfinamide (3.52 g, 29 mmol) and
1-(6-Bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-3-methoxy-propan-1-on-
e (9.1 g, 24.18 mmol) in THF (100 ml) was stirred at 60.degree. C.
under a nitrogen atmosphere for 34 hours. The cold reaction mixture
was diluted with ethyl acetate and poured onto icecold brine (200
ml) with gentle stirring. The precipitate was filtered through a
pad of hyflo and and washed with ethyl acetate. The filtrate was
diluted with ethyl acetate and washed with brine, dried over sodium
sulfate, filtered and evaporated. The crude yellowish-brown oil
(10.67 g) was chromatographed over silica gel (Redisep column 120
g, cyclohexane/ethyl acetate 95:5) to give the title compound as a
yellow-orange oil. 7.51 g (63.5% yield).
[0390] TLC (cyclohexane/ethyl acetate 10:1): R.sub.f=0.23;
[0391] LC-MS: Rt.sub.H1=1.53 min (98%, ESI+-MS: m/z 479
[(M+H).sup.+, 1Br], 481).
c)
(R)-3-(6-Bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-2,2-difluoro-5--
methoxy-3-((S)-2-methyl-propane-2-sulfinylamino)-pentanoic acid
ethyl ester
[0392] To a suspension of zinc (3.07 g, 47 mmol) and copper(I)
chloride (233 mg, 2.349 mmol) in dry THF (90 ml) were added 4 drops
of trimethylchlorosilane under nitrogen to activate the zinc. After
10 minutes ethyl 2-bromo-2,2-difluoroacetate (9.54 g, 47 mmol) was
added slowly by syringe over a period of 20 minutes between
25.degree. and 30.degree. C. adjusted with an external cooling bath
(exothermic). The reaction mixture was kept in an ultrasound bath
for 30 minutes. This black fine suspension was added drop wise to a
solution of (S)-2-methyl-propane-2-sulfinic acid
[1-(6-bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-3-methoxy-prop-(E)-y-
lidene]-amide (7.51 g, 15.66 mmol) in dry THF (75 ml) at 0.degree.
C. under inert atmosphere. After 15 min the reaction mixture was
kept at 50.degree. C. for 2 h and was then added to a cold aq.
ammonium chloride solution (5%). Ethyl acetate was added and the
organic phase was washed with aq. citric acid (5% solution), water,
sat. sodium bicarbonate solution and brine, dried over sodium
sulfate, filtered and concentrated. The crude yellowish oil (9.77
g, roughly a 4:1 mixture of diastereoisomers) was chromatographed
over silica gel (Redisep column 120 g, cyclohexane/ethyl acetate
85:15) to give the title compound as a yellow oil. 6.11 g yellow
oil. (64.6% yield).
[0393] TLC (cyclohexane/ethyl acetate 2:1): R.sub.f=0.47;
[0394] LC-MS: Rt.sub.H1=1.54 min (100%, ESI+-MS: m/z 604
[(M+H).sup.+, 1Br], 606);
[0395] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.45 (d, J=2.5
Hz, 1H), 6.63 (br. s, 1H), 4.22-4.04 (m, 2H), 3.77-3.68 (m, 1H),
3.31-3.20 (m, 1H), 3.15 (s, 3H), 3.11-3.00 (m, 1H), 2.97-2.84 (m,
1H), 1.35 (s, 9H), 1.15 (t, J=7.2 Hz, 3H), 1.04-0.95 (m, 9H),
0.94-0.83 (m, 6H).
[0396] The minor diastereoisomer R.sub.f=0.35 (2:1
cyclohexane:ethyl acetate was not isolated.
d)
(R)-3-(6-Bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-5-methoxy-3-((S)-2-m-
ethyl-propane-2-sulfinylamino)-pentanoic acid ethyl ester
[0397] Freshly ground KF (1.174, 20.21 mmol) was added to a
solution of
(R)-3-(6-bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-2,2-difluoro-5-me-
thoxy-3-((S)-2-methyl-propane-2-sulfinylamino)-pentanoic acid ethyl
ester (6.10 g, 10.11 mmol) and acetic acid (1.157 ml, 20.21 mmol)
in THF (39.8 ml). DMF (39.8 ml) was added and the suspension was
stirred at rt. After 6 h the reaction mixture was diluted with
ethyl acetate and washed with sat. sodium bicarbonate solution and
brine, dried over sodium sulfate, filtered and evaporated. The
crude product (4.85 g, 98% yield) was used without purification in
the next step.
[0398] TLC (cyclohexane/ethyl acetate 1:1): R.sub.f=0.33;
[0399] LC-MS: Rt.sub.H1=1.11 min (100%, ESI+-MS: m/z 489
[(M+H).sup.+, 1Br], 491);
[0400] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.56-7.48 (m,
1H), 7.41-7.30 (m, 1H), 6.54 (br. s, 1H), 4.25-4.05 (m, 2H),
3.77-3.64 (m, 1H), 3.34-3.22 (m, 1H), 3.15 (s, 3H), 3.08-2.97 (m,
1H), 2.94-2.86 (m, 1H), 1.34 (s, 9H), 1.18 (t, J=7.3 Hz, 3H).
e) (S)-2-Methyl-propane-2-sulfinic acid
[(R)-1-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-3-hydroxy-1-(2-methox-
y-ethyl)-propyl]-amide
[0401] To a solution of
(R)-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-5-methoxy-3-((S)-2-met-
hyl-propane-2-sulfinylamino)-pentanoic acid ethyl ester (2.4 g,
4.90 mmol) in THF (38 ml) was added lithiumborohydride (214 mg,
9.81 mmol) in 2 portions. The slightly exothermic reaction was
stirred for 6 hours at room temperature. Crushed ice was added
carefully and the reaction mixture was diluted with ethyl acetate.
The organic phase was washed with water and brine, dried over
sodium sulfate, filtered and evaporated. The crude yellowish resin
(2.05 g) was chromatographed over silica gel (Redisep column 40 g,
cyclohexane/ethyl acetate 4:6) to give the title compound as a
colourless resin. 1.50 g (68.4% yield).
[0402] TLC (cyclohexane/ethyl acetate 1:1): R.sub.f=0.13;
[0403] LC-MS: Rt.sub.H1=0.84 min (100%, ESI+-MS: m/z 447
[(M+H).sup.+, 1Br], 449);
[0404] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.55-7.45 (m,
1H), 7.37-7.29 (m, 1H), 6.34-6.25 (br. s, 1H), 3.95-3.63 (m, 2+1H),
3.40-3.27 (m, 1H), 3.18 (s, 3H), 3.05-2.94 (m, 1H), 2.84-2.73 (m,
1H), 2.19-2.11 (m, 1H, OH), 1.35 (s, 9H).
f)
(R)-3-Amino-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-5-methoxy-pe-
ntan-1-ol
[0405] To a solution of (S)-2-methyl-propane-2-sulfinic acid
[(R)-1-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-3-hydroxy-1-(2-methox-
y-ethyl)-propyl]-amide (1.50 g, 3.33 mmol) in methanol (8.4 ml) was
added 2M HCl in diethyl ether (6.56 ml, 13.11 mmol). The reaction
mixture was stirred for 1.5 h at room temperature. 7 M ammonia in
methanol (2.7 ml) was added to the reaction mixture and the
resulting colourless suspension was evaporated in vacuo. The
remaining solid was triturated with warm dichloromethane, cooled to
rt, filtered and rinsed with dichloromethane. The filtrate was
evaporated affording the title compound which was used without
purification in the next step. 1.42 g colourless, viscous oil. 100%
yield.
[0406] TLC (cyclohexane/ethyl acetate 4:6): R.sub.f=0.41;
[0407] LC-MS: Rt.sub.H1=0.52 min (100%, ESI+-MS: m/z 343
[(M+H).sup.+, 1Br], 345);
[0408] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.52 (dd, J=3.1,
8.4 Hz, 1H), 7.34 (dd, J=8.4, 9.9 Hz, 1H), 4.23-4.06 (m, 1H), 3.81
(s, 1H+OH), 3.66-3.56 (m, 1H), 3.30-3.21 (m, 1H), 3.17 (s, 3H),
2.77-2.66 (m, 1H), 2.57-2.43 (m, 1H).
g)
N--[(R)-4-(6-Bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-(2-methoxy-eth-
yl)-5,6-dihydro-4H-[1,3]oxazin-2-yl]-4-nitro-benzamide
[0409] To a solution of
(R)-3-amino-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-5-methoxy-pent-
an-1-ol (1.15 g, 3.35 mmol) in THF (27.9 ml) was added
nitrobenzoyl-isothiocyanate (767 mg, 3.69 mmol). After stirring at
rt for 4 hr DCC (760 mg, 3.69 mmol) and triethylamine (34.1 mg,
0.337 mmol) was added. Stirring was continued at rt for 19 hr and
finally, the reaction mixture was kept at 70.degree. C. for 5 h.
The yellow-orange solution was cooled and evaporated in vacuo. The
crude product (2.7 g) was chromatographed over silica gel (Redisep
column 120 g, cyclohexane/ethyl acetate 7:3) to give the title
compound as a light yellow foam. 650 mg (35.6% yield).
[0410] TLC (cyclohexane/ethyl acetate 7:3): R.sub.f=0.17;
[0411] LC-MS: Rt.sub.H1=1.15 min (95%, ESI+-MS: m/z 517
[(M+H).sup.+, 1Br], 519);
[0412] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 12.07 (br. s,
1H), 8.49 (d, J=9.0 Hz, 2H), 8.29 (d, J=8.9 Hz, 2H), 7.68-7.58 (m,
1H), 7.49-7.40 (m, 1H), 4.59-4.42 (m, 1H), 4.35-4.19 (m, 1H),
3.87-3.72 (m, 1H), 3.54-3.39 (m, 1H), 3.35 (s, 3H), 3.02-2.88 (m,
1H), 2.71-2.57 (m, 1H).
h)
(R)-4-(6-Bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-(2-methoxy-ethyl)--
5,6-dihydro-4H-[1,3]oxazin-2-ylamine
[0413] A suspension of
N--[(R)-4-(6-bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-(2-methoxy-ethyl-
)-5,6-dihydro-4H[1,3]oxazin-2-yl]-4-nitro-benzamide (640 mg, 1.237
mmol) and potassium carbonate (513 mg, 3.71 mmol) in methanol (18.7
ml) was stirred for 22 h at rt. The resulting yellow solution was
evaporated, diluted with ethyl acetate and washed with water and
brine, dried over sodium sulfate, filtered and evaporated. 400 mg
yellow solid (88% yield). The crude product was used in the next
step without purification.
[0414] TLC (cyclohexane/ethyl acetate 1:1): R.sub.f=0.14;
[0415] LC-MS: Rt.sub.H1=0.59 min (100%, ESI+-MS: m/z 368
[(M+H).sup.+, 1Br], 370);
[0416] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.53-7.43 (m,
1H), 7.28 (s, 1H), 4.35-4.18 (m, 1H), 4.14-4.01 (m, 1H), 3.71-3.62
(m, 1H), 3.53-3.40 (m, 1H), 3.30 (s, 3H), 3.26-3.10 (m, 1H),
3.05-2.93 (m, 1H), 2.32-2.14 (br. s, 1H, NH), 1.77-1.47 (br. s, 2H,
NH plus res. water).
i)
[Bis-(4-methoxy-phenyl)-phenyl-methyl]-[(R)-4-(6-bromo-3-fluoro-pyridin-
-2-yl)-5,5-difluoro-4-(2-methoxy-ethyl)-5,6-dihydro-4H-[1,3]oxazin-2-yl]-a-
mine
[0417] To a solution of
(R)-4-(6-bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-(2-methoxy-ethyl)-5,-
6-dihydro-4H-[1,3]oxazin-2-ylamine (200 mg, 0.543 mmol) and
triethylamine (110 mg, 1.087 mmol) in dichloromethane (5.4 ml) was
added solid 4,4'-dimethoxytrityl chloride (202 mg, 0.598 mmol)
under argon atmosphere. The green solution was stirred at rt for 16
hrs and was then evaporated in vacuo. The crude product was taken
up with ethyl acetate and washed with aqueous citric acid, aqueous
sodium bicarbonate solution, water and brine. The organic phase was
dried over sodium sulfate, filtered and evaporated. The crude
product (380 mg) was chromatographed over silica gel (Redisep
column 12 g, cyclohexane/ethyl acetate 8:2) to give the title
compound as a colourless foam. 339 mg (93% yield).
[0418] TLC (cyclohexane/ethyl acetate 8:2): R.sub.f=0.29;
[0419] LC-MS: Rt.sub.H1=1.23 min (100%, ESI+-MS: m/z 670
[(M+H).sup.+, 1Br], 672);
[0420] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 7.49-7.16 (m,
11H), 6.87-6.78 (m, 4H), 5.41-5.28 (m, 1H), 3.87-3.59 (m, 9H), 3.07
(m, 4H), 2.99-2.85 (m, 1H), 2.74-2.60 (m, 1H).
j) 5-Cyano-3-methyl-pyridine-2-carboxylic acid
{6-[(R)-2-{[bis-(4-methoxy-phenyl)-phenyl-methyl]-amino}-5,5-difluoro-4-(-
2-methoxy-ethyl)-5,6-dihydro-4H-[1,3]oxazin-4-yl]-5-fluoro-pyridin-2-yl}-a-
mide
[0421] A degassed mixture of
[bis-(4-methoxy-phenyl)-phenyl-methyl]-[(R)-4-(6-bromo-3-fluoro-pyridin-2-
-yl)-5,5-difluoro-4-(2-methoxy-ethyl)-5,6-dihydro-4H-[1,3]oxazin-2-yl]-ami-
ne (330 mg, 0.492 mmol), 5-cyano-3-methyl-pyridine-2-carboxylic
acid amide (95 mg, 0.591 mmol),
rac-trans-N,N'-dimethylcyclohexane-1,2-diamine (21.65 mg, 0.148
mmol), potassium carbonate (150 mg, 1.083 mmol) and copper iodide
(28.1 mg, 0.148 mmol) was refluxed under argon in dioxane (12.3 ml)
for 20 hrs. The reaction mixture was evaporated, taken up in ethyl
acetate and washed with aqueous sodium bicarbonate solution, water
and brine, dried over sodium sulfate, filtered and evaporated to
give 406 mg red-brown foam. The crude product was chromatographed
over silica gel (Redisep column 12 g, toluene/ethyl acetate 8:2) to
give the title compound as a pinky foam. 152 mg (37.4% yield).
[0422] TLC (toluene/ethyl acetate 8:2): R.sub.f=0.37;
[0423] LC-MS: Rt.sub.H1=1.22 min (91% pure; ESI+-MS: 751).
k) 5-Cyano-3-methyl-pyridine-2-carboxylic acid
{6-[(R)-2-amino-5,5-difluoro-4-(2-methoxy-ethyl)-5,6-dihydro-4H-[1,3]oxaz-
in-4-yl]-5-fluoro-pyridin-2-yl}-amide
[0424] A solution of 5-cyano-3-methyl-pyridine-2-carboxylic acid
{6-[(R)-2-{[bis-(4-methoxy-phenyl)-phenyl-methyl]-amino}-5,5-difluoro-4-(-
2-methoxy-ethyl)-5,6-dihydro-4H-[1,3]oxazin-4-yl]-5-fluoro-pyridin-2-yl}-a-
mide (146 mg, 0.194 mmol), TFA (0.989 ml, 12.83 mmol) and
triethylsilane (0.093 ml, 0.583 mmol) in dichloromethane (1.9 ml)
was stirred at rt for 18 hours. The reaction mixture was evaporated
and the residue diluted with ethyl acetate, washed with sat.
aqueous sodium bicarbonate solution, water and brine, dried over
sodium sulfate, filtered and evaporated. 142 mg colourless resin.
The product was chromatographed over a preparative silica gel plate
(2 mm, 20.times.20 cm, Merck, dichloromethane/methanol 95:5) to
give the title compound as a colourless foam. 74 mg (85%
yield).
[0425] TLC (dichloromethane/methanol 95:5, silica gel, UV 254):
R.sub.f=0.28;
[0426] LC-MS: Rt.sub.H1=0.76 min (100% pure; ESI+-MS: 449
[(M+H).sup.+]);
[0427] .sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta.=10.70 (br. s,
1H, NH), 9.00 (br. s, 1H), 8.45 (br. s, 1H), 8.30-8.13 (m, 1H),
7.84-7.66 (m, 1H), 5.88 (br. s, 3H), 4.45-4.25 (m, 1H), 4.19-4.00
(m, 1H), 3.62-3.44 (m, 1H), 3.27-3.18 (m, 1H), 3.16 (s, 3H),
2.96-2.83 (m, 1H), 2.61 (s, 3H), 2.00-1.88 (m, 1H).
Examples 5-6
[0428] The compounds listed in Table 3 were prepared by a procedure
analogous to that used in Example 4. However, for Example 5
(R)-tert.-butylsulfinamide was used to form the sulfoximine in step
4b.
TABLE-US-00004 TABLE 3 MS [m/z; Example Compound .sup.1H-NMR
(solvent; .delta.) (M + 1).sup.+] 5 ##STR00028## (400 MHz,
CDCl.sub.3): .delta. 10.69 (br s, 1H), 8.92- 8.82 (m, 1H),
8.55-8.43 (m, 1H), 7.96-7.87 (m, 1H), 7.68-7.58 (m, 1H), 4.61-4.45
(m, 1H), 4.31-4.17 (m, 1H), 3.65-3.56 (m, 2H), 3.32 (s, 3H), 3.01-
2.88 (m, 1H), 2.81 (s, 3H), 2.58-2.43 (m, 1H) LCMS: Rt.sub.H3 =
0.75 [M + 1] = 449 5-Cyano-3-methyl-pyridine-2-carboxylic acid
{6-[(S)-2-amino-5,5-difluoro-4-(2-methoxy-
ethyl)-5,6-dihydro-4H-[1,3]oxazin-4-yl]-5-
fluoro-pyridin-2-yl}-amide 6 ##STR00029## (400 MHz, CDCl.sub.3):
.delta. 10.47 (br s, 1H), 8.82 (s, 1H), 8.41 (dd, 1H), 8.06 (s,
1H), 7.49 (t, 1H), 4.25-4.33 (d, 1H), 3.97-4.20 (m, 1H), 3.42-3.56
(m, 2H), 3.19 (s, 3H), 2.78-2.92 (m, 1H), 2.15-2.31 (m, 1H) LCMS:
Rt.sub.H2 = 0.81 [M + 1] = 514.0
3-Chloro-5-trifluoromethyl-pyridine-2- carboxylic acid
{6-[(R)-2-amino-5,5-difluoro- 4-(2-methoxy-ethyl)-5,6-dihydro-4H-
[1,3]oxazin-4-yl]-5-fluoro-pyridin-2-yl}-amide
Example 7
3-Chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide
##STR00030##
[0429] a)
[Bis-(4-methoxy-phenyl)-phenyl-methyl]-[(R)-4-(6-bromo-3-fluoro--
pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-2-A-amine
[0430]
(R)-4-(6-bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dih-
ydro-4H-[1,3]oxazine-2-ylamine (5 g, 15.43 mmol, Example 1
intermediate h) was dissolved in DCM (154 ml) under argon,
triethylamine (4.30 mL, 30.9 mmol) and 4,4'-dimethoxytrityl
chloride (5.75 g, 16.97 mmol) were added and the reaction mixture
was stirred at rt for 18 hours. The solvent was removed in vacuo
and the residue was taken up in ethyl acetate. The organic layer
was washed with aq 10% citric acid, water, aqueous saturated sodium
bicarbonate solution and brine, dried over sodium sulfate, filtered
and concentrated. The crude product was chromatographed over silica
gel (Redisep column 120 g, cyclohexane/ethyl) to give the title
compound: 8.16 g (69.2% yield).
[0431] TLC (cyclohexane/ethyl acetate 3:1, silica gel, UV 254):
R.sub.f=0.45;
[0432] LC-MS: Rt.sub.H2=1.37 min; (ESI+-MS: m/z 626
[(M+H).sup.+,1Br]; 628);
[0433] .sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 7.71 (dd, 1H),
7.64 (dd, 1H), 7.32-7.08 (m, 9H), 6.86 (s, 1H), 6.81-6.77 (m, 4H),
4.07-4.05 (m, 1H), 4.02-3.98 (m, 1H), 3.71 (s, 6H), 1.05 (br. s.,
3H).
b)
[(R)-4-(6-Amino-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydr-
o-4H-[1,3]oxazin-2-yl]-[bis-(4-methoxy-phenyl)-phenyl-methyl]-amine
[0434] To a solution of
[bis-(4-methoxy-phenyl)-phenyl-methyl]-[(R)-4-(6-bromo-3-fluoro-pyridin-2-
-yl)-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-2-yl]-amine
(23.4 g, 28.8 mmol) in ammonia (173 ml, 1.21 mol, 7M in methanol)
in a microwave vial was added ethylene glycol (240 ml) and methanol
(240 ml). Copper oxide Cu.sub.2O (1.21 g, 8.46 mmol) was added and
the vial was sealed. The reaction mixture was stirred at 80.degree.
C. for 43 hours. The cold reaction mixture was diluted with ethyl
acetate and washed with water, aqueous ammonia and brine. The
organic layer was dried over sodium sulfate, filtered and
evaporated. The crude product was chromatographed over silica gel
(400 g, dichloromethane/methanol 98:2+0.2% ammonia) to give the
title compound: 4.29 g (25% yield).
[0435] TLC (dichloromethane/methanol 95:5+0.5% ammonia, silica gel,
UV 254): R.sub.f=0.29;
[0436] LC-MS: Rt.sub.H2=1.03 min; (ESI+-MS: m/z 563
[(M+H).sup.+]);
[0437] .sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 7.25-7.32 (m,
2H) 7.10-7.24 (m, 8H) 6.77 (d, 4H) 6.59 (s, 1H) 6.41 (dd, 1H) 5.77
(d, 2H) 4.09-4.22 (m, 1H) 3.91-4.01 (m, 1H) 3.70 (s, 6H) 0.97 (br.
s., 3H).
c) 3-Chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
[6-((R)-5,5-difluoro-2-{[(4-methoxy-phenyl)-(3-methoxy-phenyl)-phenyl-met-
hyl]-amino}-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-y-
l]-amide
[0438]
[(R)-4-(6-amino-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-di-
hydro-4H-[1,3]oxazin-2-yl]-[bis-(4-methoxy-phenyl)-phenyl-methyl]-amine
(250 mg, 0.444 mmol), 3-chloro-5-(trifluoromethyl)-picolinic acid
(120 mg, 0.533 mmol) and HOAt (109 mg, 0.800 mmol) were dissolved
in DMF (4.44 ml) under argon. EDC.times.HCl (128 mg, 0.667 mmol)
was added and the reaction mixture was stirred at rt for 18 hours.
The reaction mixture was diluted with ethyl acetate, washed with
water and brine, dried over sodium sulfate, filtered and
concentrated. The crude product was chromatographed over silica gel
(Redisep column 12 g, cyclohexane/ethyl acetate) to give the title
compound: 100 mg (29.2% yield).
[0439] LC-MS: Rt.sub.H2=1.43 min; (96% purity; ESI+-MS: m/z 770
[(M+H).sup.+,1Cl]; 772);
[0440] .sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 11.22 (s, 1H),
9.08 (s, 1H), 8.72 (s, 1H), 8.16 (dd, 1H), 7.71 (dd, 1H), 7.30-7.24
(m, 2H), 7.23-7.10 (m, 7H), 6.81-6.74 (m, 5H), 4.33-4.23 (m, 1H),
4.08-4.00 (m, 1H), 3.70 (s, 6H), 1.06 (br. s, 3H).
d) 3-Chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide
[0441] 3-Chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
[6-((R)-5,5-difluoro-2-{[(4-methoxy-phenyl)-(3-methoxy-phenyl)-phenyl-met-
hyl]-amino}-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-y-
l]-amide (80 mg, 0.104 mmol) was dissolved in dichloromethane
(0.1039 ml), TFA (80.0 .mu.l, 1.04 mmol) was added and the reaction
mixture was stirred at rt for 18 hours. The reaction mixture was
poured onto a mixture of ice ethyl acetate and NH.sub.4OH (w=25%).
The organic layer was washed with water, brine, dried over sodium
sulfate, filtered and concentrated. The crude product was
chromatographed over silica gel (column 4 g,
dichloromethane/methanol 95:5+0.5% ammonia) to give the title
compound: 32 mg (65.9% yield).
[0442] LC-MS: Rt.sub.H1=0.79 min; (100% purity; ESI+-MS: m/z 468
[(M+H).sup.+,1Cl]; 470);
[0443] .sup.1H-NMR (400 MHz, CDCl.sub.3): .delta. 10.21 (br. s,
1H), 8.86 (d, 1H), 8.40 (dd, 1H), 8.17 (d, 1H), 7.53 (dd, 1H),
4.21-4.13 (m, 4H), 1.83 (t, 3H).
Example 7a
Alternative synthesis of
3-chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-y-
l)-5-fluoro-pyridin-2-yl]-amide
a)
(R)-4-(6-Bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydro-
-4H-[1,3]oxazin-2-ylamine
[0444] The (+)-campher sulfonic acid salt of
(R)-3-amino-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-butan-1-ol
(12.75 g, 23.99 mmol) was partitioned between TBME and aq.
Na.sub.2CO.sub.3 (w=10%), the layers were separated, the aq. layer
was extracted with TBME, the organic layer was extracted with sat.
aq. NaCl. The combined organic layers were dried with
Na.sub.2CO.sub.3, the solvent evaporated to yield the free base as
white crystals.
[0445] To a solution of
(R)-3-amino-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-butan-1-ol
(9.49 g, 31.7 mmol) in EtOH (256 ml) was added NaHCO.sub.3 (1.066
g, 12.69 mmol) and cyanogen bromide (10.08 g, 95 mmol) and the
mixture was warmed to 85.degree. C. over night. After cooling to rt
the solvent was evaporated and the residue taken up in 1N HCl and
TBME, the layers were separated and the organic layer was washed
with 1N HCl. The aq. layers were combined, basified by addition of
solid Na.sub.2CO.sub.3 and extracted with TBME (2.times.). The
combined TBME extracts were washed with sat. aq. NaCl, dried with
K.sub.2CO.sub.3 to provide the desired product as yellow resin.
This material was used for the next step without further
purification.
[0446] HPLC: Rt.sub.H5=2.716 min; ESIMS [M+H].sup.+=324.0/326.0;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 7.76-7.59 (m, 2H),
5.85 (s, 2H), 4.43-4.30 (m, 1H), 4.24-4.10 (m, 1H), 1.63 (br. s,
3H).
b)
(R)-4-(6-Amino-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydro-
-4H-[1,3]oxazin-2-ylamine
[0447] To a solution of
(R)-4-(6-bromo-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydro-4-
H-[1,3]oxazin-2-ylamine (8.73 g, 23.17 mmol) in ethylene glycol
(139 ml) and aq. NH.sub.3 (w=25%, 108 ml) in an autoclave was added
copper(I) oxide (497 mg, 3.47 mmol) and the mixture was warmed to
60.degree. C. over night. After cooling to rt the mixture was
extracted with EtOAc, the organic layer was washed with aq.
NH.sub.3 (w=12%, 2.times.), the combined organic layers were washed
with sat. aq. NaCl, dried with Na.sub.2SO.sub.4 and evaporated. The
residue was dissolved in TBME and extracted with 1N HCl (2.times.).
The combined aq. layers were basified by addition of solid
Na.sub.2CO.sub.3 some NaCl was added and the aq. solution extracted
with DCM (4.times.). The combined DCM extracts were dried with
K.sub.2CO.sub.3 and evaporated to provide the title compound as
greyish resin. The crude material was used for the next step
without further purification.
[0448] HPLC: Rt.sub.H5=2.584 min; ESIMS [M+H].sup.+=261.0;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 7.23 (dd, 1H), 6.40
(dd, 1H), 5.77 (s, 2H), 5.63 (s, 2H), 4.29-4.15 (m, 2H), 1.56 (s,
3H).
c)
[(R)-4-(6-Amino-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydr-
o-4H-[1,3]oxazin-2-yl]-carbamic acid tert-butyl ester
[0449] To a solution of
(R)-4-(6-amino-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydro-4-
H-[1,3]oxazin-2-ylamine (4.53 g, 17.41 mmol) in DCM (46 ml) was
added DIPEA (4.26 ml, 24.37 mmol) and Boc.sub.2O (4.56 g, 20.89
mmol) and the mixture was warmed to 40.degree. C. over night. The
solvent was evaporated (at 34.degree. C.) and the residue was
purified by chromatography on silica gel (cyclohexane/[EtOAc/MeOH
95:5] 4:1 to 1:1) to provide the title compound as colorless foam.
HPLC: Rt.sub.H5=3.001 min; ESIMS [M+H].sup.+=361.2; .sup.1H-NMR
(600 MHz, CDCl.sub.3): .delta. 7.26 (t, 1H), 6.51 (d, 1H), 4.51
(br. s, 2H), 4.40-4.29 (m, 2H), 1.91 (s, 3H), 1.52 (s, 9H).
d)
((R)-4-{6-[(3-Chloro-5-trifluoromethyl-pyridine-2-carbonyl)-amino]-3-fl-
uoro-pyridin-2-yl}-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-2-yl)--
carbamic acid tert-butyl ester
[0450] To a solution of
[(R)-4-(6-amino-3-fluoro-pyridin-2-yl)-5,5-difluoro-4-methyl-5,6-dihydro--
4H-[1,3]oxazin-2-yl]-carbamic acid tert-butyl ester (134 mg, 0.372
mmol) in DMF (1.3 ml) was added
3-chloro-5-trifluoromethyl-pyridine-2-carboxylic acid (101 mg,
0.446 mmol) and HOAt (91 mg, 0.669 mmol). The mixture was cooled to
0.degree. C., EDC*HCl (107 mg, 0.558) was added and the mixture
stirred for 1 h while allowing to warm to rt. To the reaction
mixture was added TBME and water, the layers were separated and the
aq. layer extracted with TBME. The combined organic layers were
washed with sat. aq. NaHCO.sub.3, sat. aq. NaCl, dried with
MgSO.sub.4 and evaporated. The residue was purified by
chromatography on silica gel (cyclohexane/EtOAc 6:1 to 5:1) to
provide the title compound as colorless solid.
[0451] HPLC: Rt.sub.H7=2.920 min; ESIMS [M+H].sup.+=568.0/570,0;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 11.25 (s, 1H), 9.65
(s, 1H), 9.08 (br. s, 1H), 8.72 (br. s, 1H), 8.23 (d, 1H), 7.83 (t,
1H), 4.57-4.41 (m, 2H), 1.72 (s, 3H), 1.40 (s, 9H).
e) 3-Chloro-5-trifluoromethyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide
[0452] To a solution of
((R)-4-{6-[(3-chloro-5-trifluoromethyl-pyridine-2-carbonyl)-amino]-3-fluo-
ro-pyridin-2-yl}-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-2-yl)-ca-
rbamic acid tert-butyl ester (180 mg, 0.317 mmol) in DCM (1.5 ml)
was added TFA (0.5 ml) and the mixture was stirred at rt for 1 h.
The reaction mixture was poured on 10% aq. Na.sub.2CO.sub.3, more
DCM was added and the layers were separated. The aq. phase was
extracted with DCM (3.times.), the combined DCM phases were dried
with K.sub.2CO.sub.3 and evaporated to provide the title compound
as colorless solid.
[0453] HPLC: Rt.sub.H8=3.001 min; ESIMS [M+H].sup.+=468.0/470,0;
.sup.1H-NMR (600 MHz, CDCl.sub.3): .delta. 10.22 (br. s, 1H), 8.87
(s, 1H), 8.41 (dd, 1H), 8.18 (s, 1H), 7.53 (t, 1H), 4.33-4.13 (m,
4H), 1.85 (s, 3H).
Examples 8 to 21
[0454] The compounds listed in Table 4 were prepared by a procedure
analogous to that used in Example 7.
TABLE-US-00005 TABLE 4 MS [m/z; Example Compound .sup.1H-NMR
(solvent; .delta.) (M + 1).sup.+] 8 ##STR00031## (400 MHz,
DMSO-d.sub.6): .delta. 10.28 (s, 1H), 8.38 (s, 1H), 8.15 (dd, 1H),
8.10 (br s, 2H), 7.80 (dd, 1H), 5.79 (s, 2H), 4.40-4.18 (m, 2H),
1.67 (s, 3H) LCMS: Rt.sub.H2 = 0.78 [M + 1] = 450.1
3-Amino-5-trifluoromethyl-pyrazine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-
5-fluoro-pyridin-2-yl]-amide 9 ##STR00032## (400 MHz,
DMSO-d.sub.6): .delta. 10.97 (br s, 1H), 8.73 (s, 1H), 8.45 (s,
1H), 8.17 (dd, 1H), 7.75 (dd, 1H), 5.75 (br s, 2H), 4.36-4.28 (m,
2H), 1.66 (s, 3H) LCMS: Rt.sub.H2 = 0.75; [M + 1] = 434.0/ 436.0
3,5-Dichloropyridine-2-carboxylic acid [6-
((R)-2-amino-5,5-difluoro-4-methyl-5,6-
dihydro-4H-[1,3]oxazin-4-yl)-5-fluoro- pyridin-2-yl]-amide 10
##STR00033## (400 MHz, DMSO-d.sub.6): .delta. 9.93 (s, 1H), 8.16
(dd, 1H), 7.89 (br s, 2H), 7.78-7.73 (m, 1H), 7.73 (s, 1H), 5.78
(s, 2H), 5.05 (q, 2H), 4.36-4.27 (m, 1H), 4.25-4.16 (m, 1H), 1.66
(s, 3H) LCMS: Rt.sub.H2 = 0.43; [M + 1] = 480.5
3-Amino-5-(2,2,2-trifluoro-ethoxy)pyrazine- 2-carboxylic acid
[6-((R)-2-amino-5,5- difluoro-4-methyl-5,6-dihydro-4H-
[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]-amide 11 ##STR00034## (400
MHz, DMSO-d.sub.6): .delta. 9.96 (br s., 1H), 8.19 (dd, 1H), 8.03-
7.75 (m, 3H), 7.67 (s, 1H), 6.46 (tt, 1H), 4.63 (td, 2H), 4.42-4.31
(m, 2H), 1.71 (br s, 3H) LCMS: Rt.sub.H2 = 0.78; [M + 1] = 462.1
3-Amino-5-(2,2-difluoro-ethoxy)-pyrazine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-
5-fluoro-pyridin-2-yl]-amide 12 ##STR00035## (400 MHz,
DMSO-d.sub.6): .delta. 10.14 (br s, 1H), 8.28 (d, 1H), 7.96 (t,
1H), 7.79 (br s, 2H), 7.56 (s, 1H), 4.96 (br s, 1H), 4.80 (br s,
1H), 4.68 (t, 1H), 4.56 (t, 1H), 4.43 (t, 2H), 2.16 (dquin, 2H),
1.91 (br s, 3H) LCMS: Rt.sub.H2 = 0.80; [M + 1] = 458.1
3-Amino-5-(3-fluoro-propoxy)-pyrazine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-
5-fluoro-pyridin-2-yl]-amide 13 ##STR00036## (400 MHz, CDCl3):
.delta. 10.49 (s, 1H), 8.36 (dd, 1H), 8.17 (d, 1H), 7.45 (dd, 1H),
7.08 (dd, 1H), 4.40 (br s, 2H), 4.28-4.08 (m, 2H), 3.92 (s, 3H),
2.79 (s, 3H), 1.85 (t, 3H) LCMS: Rt.sub.H2 = 0.77; [M + 1] = 411.1
5-Methoxy-3-methyl-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-
5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-fluoro- pyridin-2-yl]-amide 14
##STR00037## (400 MHz, DMSO-d.sub.6): .delta. 10.26 (s, 1H), 8.19
(dd, 1H), 7.95 (d, 1H), 7.75 (dd, 1H), 7.36 (d, 1H), 7.09 (br s,
2H), 5.79 (s, 2H), 4.39 (s, 2H), 4.37- 4.26 (m, 1H), 4.26- 4.12 (m,
1H), 3.32 (s, 3H), 1.67 (s, 3H) LCMS: Rt.sub.H2 = 0.78; [M + 1] =
450.1 3-Amino-5-(3-methoxy-prop-1-ynyl)- pyridine-2-carboxylic acid
[6-((R)-2-amino- 5,5-difluoro-4-methyl-5,6-dihydro-4H-
[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]- amide 15 ##STR00038##
(400 MHz, DMSO-d.sub.6): .delta. 9.96 (s, 1H), 8.17 (dd, 1H), 7.89
(br s, 2H), 7.76 (dd, 1H), 7.71 (s, 1H), 6.11 (d, 2H), 5.78 (s,
2H), 4.37- 4.27(m, 1H), 4.26- 4.15 (m, 1H), 1.66 (s, 3H) LCMS:
Rt.sub.H2 = 0.72; [M + 1] = 430.1
3-Amino-5-fluoromethoxy-pyrazine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-
5-fluoro-pyridin-2-yl]-amide 16 ##STR00039## (400 MHz,
DMSO-d.sub.6): .delta. 9.90 (s, 1H), 8.17 (d, 1H), 7.98-7.68 (m,
3H), 7.60 (s, 1H), 5.79 (s, 2H), 4.44 (br s, 2H), 4.36-4.27 (m,
1H), 4.25- 4.16 (m, 1H), 3.69 (br s, 2H), 3.32 (s, 3H), 1.66 (br s,
3H) LCMS: Rt.sub.H2 = 0.74; [M + 1] = 456.2
3-Amino-5-(2-methoxy-ethoxy)-pyrazine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-
5-fluoro-pyridin-2-yl]-amide 17 ##STR00040## (400 MHz,
DMSO-d.sub.6): .delta. 10.26 (s, 1H), 8.19 (dd, 1H), 7.91 (d, 1H),
7.75 (dd, 1H), 7.32 (d, 1H), 7.09 (br s, 2H), 5.79 (br s, 2, H),
5.46 (t, 1H), 4.44-4.26 (m, 3H), 4.26-4.13 (m, 1H), 1.67 (s, 3H)
LCMS: Rt.sub.H2 = 0.68; [M + 1] = 435.2
3-Amino-5-(3-hydroxy-prop-1-ynyl)- pyridine-2-carboxylic acid
[6-((R)-2-amino- 5,5-difluoro-4-methyl-5,6-dihydro-4H-
[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]-amide 18 ##STR00041## (400
MHz, DMSO-d.sub.6): .delta. 10.15 (s, 1H), 8.18 (dd, 1H), 7.91 (dd,
1H), 7.75 (dd, 1H), 7.25 (br s, 2H), 7.11 (dd, 1H), 5.78 (s, 2H),
4.32 (td, 1H), 4.20 (td, 1H), 1.66 (s, 3H) LCMS: Rt.sub.H2 = 0.71;
[M + 1] = 399.2 3-Amino-5-fluoro-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-
dihydro-4H-[1,3]oxazin-4-yl)-5-fluoro- pyridin-2-yl]-amide 19
##STR00042## (400 MHz, DMSO-d.sub.6): .delta. 10.18 (s, 1H), 8.18
(dd, 1H), 7.92 (d, 1H), 7.76 (dd, 1H), 7.39 (d, 1H), 7.19 (br s,
2H), 5.79 (br s, 2H), 4.39- 4.09 (m, 2H), 1.67 (s, 3H) LCMS:
Rt.sub.H2 = 0.77; [M + 1] = 415.1
3-Amino-5-chloro-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-
dihydro-4H-[1,3]oxazin-4-yl)-5-fluoro- pyridin-2-yl]-amide 20
##STR00043## (400 MHz, CDCl3): .delta. 10.44 (br s, 1H), 8.61 (d,
1H), 8.46 (d, 1H), 7.90 (d, 1H), 7.53 (t, 1H), 7.50-7.44 (m, 1H).
4.92 (br s, 2H), 4.39-4.17 (m, 2H), 1.91 (br s, 3H) LCMS: Rt.sub.H2
= 0.67; [M + 1] = 400.1 3-Chloro-pyridine-2-carboxylic acid[6-((R)-
2-amino-5,5-difluoro-4-methyl-5,6-dihydro-
4H-[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]-amide 21 ##STR00044##
(400 MHz, CDCl3): .delta. 10.45 (br s, 1H), 8.62 (d, 1H), 8.47 (dd,
1H), 7.91 (d, 1H), 7.56 (dd, 1H), 4.47-4.24 (m, 4H), 3.48 (s, 3H),
1.95 (br s, 3H) LCMS: Rt.sub.H2 = 0.80; [M + 1] = 468.1
3-Chloro-5-(3-methoxy-prop-1- ynyl)pyridine-2-carboxylic acid
[6-((R)-2- amino-5,5-difluoro-4-methyl-5,6-dihydro-
4H-[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]-amide
Examples 22 to 36
[0455] The compounds presented below in Table 5 were also prepared
by a procedure analogous to that used in Example 7. Examples 26 and
27 were separated after the deprotection step by prep. TLC
(DCM/MeOH 95:5).
TABLE-US-00006 TABLE 5 MS [m/z; Example Compound Structure
.sup.1H-NMR (solvent; .delta.) (M + 1).sup.+] 22 ##STR00045## (400
MHz, DMSO-d.sub.6): .delta. 10.44 (br s, 1H), 8.28-8.13 (m, 2H),
8.02-7.84 (m, 3H), 6.98 (t, 1H, CHF2), 4.66-4.57 (m, 2H), 1.82 (s,
3H) LCMS: Rt.sub.H2 = 0.69; [M + 1] = 432.2
3-Amino-5-difluoromethyl-pyrazine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-
fluoro-pyridin-2-yl]-amide 23 ##STR00046## (400 MHz, DMSO-d.sub.6):
.delta. 9.91 (s, 1H), 8.17 (dd, 1H), 7.87 (br s, 2H), 7.74 (d, 1H),
7.76 (d, 1H), 7.62 (s, 1H), 5.83 (br s, 1H), 4.66- 4.53 (m, 2H),
4.40-4.14 (m, 2H), 4.06-3.97 (m, 2H), 1.66 (s, 3H) LCMS: Rt.sub.H2
= 0.79; [M + 1] = 460.1/ 462.1
3-Amino-5-(2-chloro-ethoxy)-pyrazine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl}-5-
fluoro-pyridin-2-yl]-amide 24 ##STR00047## (400 MHz, DMSO-d.sub.6):
.delta. 10.68 (s, 1H), 8.46 (br s, 1H), 8.18 (d, 1H), 7.89 (s, 1H),
7.74 (t, 1H), 7.08 (d, 1H), 6.85 (d, 1H), 6.47 (t, 1H, CHF2),
4.69-4.51 (m, 2H), 4.43-4.17 (m, 2H), 1.66 (s, 3H) LCMS: Rt.sub.H2
= 0.79; [M + 1] = 480.1/ 482.1
3-Chloro-5-(2,2-difluoro-ethoxy)-pyridine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-
fluoro-pyridin-2-yl]-amide 25 ##STR00048## (400 MHz, DMSO-d.sub.6):
.delta. 10.00 (s, 1H), 8.21 (d, 1H), 7.90 (br S, 2H), 7.82 (t, 1H),
7.63 (s, 1H), 4.91-4.82 (m, 1H), 4.78-4.69 (m, 1H), 4.65-4.57 (m,
1H), 4.56-4.49 (m, 1H), 4.41 (br s, 2H), 1.75 (s, 3H) LCMS:
Rt.sub.H2 = 0.76; [M + 1] = 444.2
3-Amino-5-(2-fluoro-ethoxy)-pyrazine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-
fluoro-pyridin-2-yl]-amide 26 ##STR00049## (400 MHz, DMSO-d.sub.6):
.delta. 10.80 (s, 1H), 8.53 (s, 1H), 8.18 (d, 1H), 7.97 (s, 1H),
7.75 (t, 1H), 6.13 (s, 1H), 6.00 (s, 1H), 5.78 (br s, 2H),
4.46-4.17 (m, 2H), 1.66 (s, 3H) LCMS: Rt.sub.H2 = 0.74; [M + 1] =
448.1/ 450.2 3-Chloro-5-fluoromethoxy-pyridine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-
fluoro-pyridin-2-yl]-amide 27 ##STR00050## (400 MHz, DMSO-d.sub.6):
.delta. 10.60 (s, 1H), 8.38 (s, 1H), 8.18 (d, 1H), 7.83-7.67 (m,
2H), 5.82 (br s, 1H), 4.41- 4.15 (m, 4H), 1.66 (s, 3H), 1.38 (t,
3H) LCMS: Rt.sub.H2 = 0.81; [M + 1] = 444.1/ 446.3
3-Chloro-5-ethoxy-pyridine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-
dihydro-4H-[1,3]oxazin-4-yl)-5-fluoro-pyridin- 2-yl]-amide 28
##STR00051## (600 MHz, DMSO-d.sub.6): .delta. 9.90 (s, 1H), 8.17
(d, 1H), 7.90 (br s, 2H), 7.75 (t, 1H), 7.56 (s, 1H), 5.82 (br s,
2H), 4.32 (q, 1H), 4.20 (q, 1H), 1.66 (s, 3H) LCMS: Rt.sub.H2 =
0.79; [M + 1] = 431.3 3-Amino-5-(penta-deutero-ethoxy)-pyrazine-
2-carboxylic acid [6-((R)-2-amino-5,5-
difluoro-4-methyl-5,6-dihydro-4H-
[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]-amide 29 ##STR00052## (600
MHz, DMSO-d.sub.6): .delta. 10.16 (s, 1H), 8.18 (d, 1H), 7.90 (s,
1H), 7.77 (t, 1H), 7.62 (br s, 2H), 5.85 (br s, 1H), 4.34 (q, 1H),
4.22 (q, 1H), 3.71 (t, 2H), 3.25 (s, 3H), 2.92 (t, 2H), 1.67 (s,
3H) LCMS: Rt.sub.H2 = 0.69; [M + 1] = 440.3
3-Amino-5-(2-methoxy-ethyl)-pyrazine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-
fluoro-pyridin-2-yl]-amide 30 ##STR00053## (400 MHz, DMSO-d.sub.6):
.delta. 10.27 (s, 1H), 8.81 (s, 1H), 8.14-8.01 (m, 1H), 7.94 (s,
1H), 7.84-7.68 (m, 2H), 4.33 (t, 2H), 1.66 (s, 3H) LCMS: Rt.sub.H2
= 0.74; [M + 1] = 439.1/ 441.1
4-Chloro-1-difluoromethyl-1H-pyrazole-3- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-
fluoro-pyridin-2-yl]-amide 31 ##STR00054## (400 MHz, DMSO-d.sub.6):
.delta. 10.22 (s, 1H), 8.37 (d, 1H), 8.18 (dd, 1H), 7.97 (d, 1H),
7.78 (dd, 1H), 7.65 (br s, 2H), 5.85 (br s, 2H), 4.42- 4.15 (m,
2H), 1.68 (s, 3H) LCMS: Rt.sub.H2 = 0.60; [M + 1] = 382.2
3-Amino-pyrazine-2-carboxylic acid [6-((R)-
2-amino-5,5-difluoro-4-methyl-5,6-dihydro-
4H-[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]-amide 32 ##STR00055##
(400 MHz, DMSO-d.sub.6): .delta. 10.99 (s, 1H), 8.68 (s, 1H), 8.23
(s, 1H), 8.17 (d, 1H), 7.75 (t, 1H), 5.76 (br s, 2H), 5.52 (t, 1H),
4.39 (d, 2H), 4.32 (br s, 2H), 1.66 (s, 3H) LCMS: Rt.sub.H2 = 0.68;
[M + 1] = 454.2/ 456.1 3-Chloro-5-(3-hydroxy-prop-1-ynyl)-pyridine-
2-carboxylic acid [6-((R)-2-amino-5,5-
difluoro-4-methyl-5,6-dihydro-4H-
[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]-amide 33 ##STR00056## (400
MHz, DMSO-d.sub.6): .delta. 10.34 (s, 1H), 8.20 (dd, 1H), 8.07 (s,
1H), 7.77 (dd, 1H), 7.48 (s, 1H), 7.24 (br s, 2 H), 7.14 (t, 1 H,
CHF2), 5.80 (s, 2H), 4.39- 4.14 (m, 2H), 1.67 (s, 3H) LCMS:
Rt.sub.H2 = 0.74; [M + 1] = 431.2
3-Amino-5-difluoromethyl-pyridine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-
fluoro-pyridin-2-yl]-amide 34 ##STR00057## (400 MHz, DMSO-d.sub.6):
.delta. 9.99 (s, 1H), 8.13 (dd, 1H), 7.97 (br s, 2H), 7.80 (dd,
1H), 5.83 (br s, 2H), 4.43- 4.17 (m, 2H), 2.05 (t, 3H), 1.68 (s,
3H) LCMS: Rt.sub.H2 = 0.81; [M + 1] = 480.2/ 482.2
3-Amino-6-chloro-5-(1,1-difluoro-ethyl)- pyrazine-2-carboxylic acid
[6-((R)-2-amino- 5,5-difluoro-4-methyl-5,6-dihydro-4H-
[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]-amide 35 ##STR00058## (600
MHz, DMSO-d.sub.6): .delta. 10.41 (s, 1H), 9.26 (s, 1H), 8.64 (dd,
1H), 8.35 (d, 1H), 8.23 (d, 1H), 7.82 (t, 1H), 5.83 (br s, 2H),
4.40-4.20 (m, 2H), 1.68 (s, 3H) LCMS: Rt.sub.H2 = 0.66; [M + 1] =
391.2 5-Cyano-pyridine-2-carboxylic acid [6-((R)-
2-amino-5,5-difluoro-4-methyl-5,6-dihydro-
4H-[1,3]oxazin-4-yl)-5-fluoro-pyridin-2-yl]-amide 36 ##STR00059##
(600 MHz, CDCl.sub.3): .delta. 10.30 (br s, 1H), 8.74 (s, 1H),
8.49-8.36 (m, 1H), 8.03 (s, 1H), 7.52 (t, 1H), 4.33 (br s, 1H),
4.25-4.13 (m, 2H), 2.04 (t, 3H), 1.85 (s, 3H) LCMS: Rt.sub.H8 =
2.981; [M + 1] = 464.0/ 466.0
3-Chloro-5-(1,1-difluoro-ethyl)-pyridine-2- carboxylic acid
[6-((R)-2-amino-5,5-difluoro-
4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5-
fluoro-pyridin-2-yl]-amide
Example 37
3-Amino-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide
##STR00060##
[0457] To a solution of
3-amino-6-chloro-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic acid
[6-((R)-2-amino-5,5-difluoro-4-methyl-5,6-dihydro-4H-[1,3]oxazin-4-yl)-5--
fluoro-pyridin-2-yl]-amide [Example 34] (54 mg, 0.113 mmol) in
MeOH/THF (1:1, 10 ml) was added Pd/C 10% (BASF 4505 D/R E, 12 mg)
and the mixture was set under an hydrogen atmosphere. After 2.5 h
more Pd/C 10% (BASF 4505 D/R E, 11 mg) was added and the
hydrogenation continued for another 2.5 h. The reaction mixture was
filtered through a pad of Celite, washed with MeOH and the solvent
evaporated. The residue was purified by chromatography on silica
gel (DCM to DCM/MeOH 9:1) to provide the title compound as yellow
foam.
[0458] HPLC: Rt.sub.H2=0.76 min; ESIMS [M+H].sup.+=446.2;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 10.25 (s, 1H), 8.22
(s, 1H), 8.17 (dd, 1H), 7.92 (s, 2H), 7.79 (dd, 1H), 5.82 (br. s,
1H), 4.44-4.14 (m, 2H), 2.00 (t, 3H), 1.68 (s, 3H)
Preparation of Intermediates
[0459] Alternative synthesis of
(R)-3-amino-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-butan-1-ol
(Example 1 intermediate g):
##STR00061##
a) 1-(6-Bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-ethanone
[0460] To a solution of diisopropylamine (11.33 g, 112 mmol) in THF
(200 ml) was added n-BuLi (44.8 ml, 2.5 mol/L in hexanes) below
-50.degree. C. A solution of
2-bromo-5-fluoro-4-triethylsilanyl-pyridine (25 g, 86 mmol) in THF
(25 ml) was added to the LDA-solution at -78.degree. C. in a drop
wise manner below -65.degree. C. After 70 minutes at -78.degree. C.
DMA (10.49 ml, 112 mmol) was added drop wise in a fast manner to
the deep red solution keeping the temperature below -57.degree. C.
After 30 minutes the cooling bath was removed and the reaction
mixture was allowed to reach -40.degree. C. The cold reaction
mixture was poured on a mixture of 2M aq. HCl (160 ml)/water (200
ml)/brine (100 ml). Tert.-butyl methyl ether was added and the
layers were separated. The organic phase was washed twice with
brine, dried over magnesium sulfate, filtered and evaporated to
give a yellow oil. The crude product (28.67 g) was used in the next
step without purification.
[0461] TLC (cyclohexane/ethyl acetate 10:1): R.sub.f=0.61;
[0462] LC-MS: Rt.sub.H1=1.46 min; (98% purity; ESI+-MS: m/z 332
[(M+H).sup.+,1Br]; 334);
[0463] .sup.1H-NMR (400 MHz, CDCl.sub.3): 7.59 (d, J=2.8 Hz, 1H),
2.70 (s, 3H), 1.06-0.83 (m, 15H).
b)
(R)-3-(6-Bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-2,2-difluoro-3--
((R)-2-methyl-propane-2-sulfinylamino)-butyric acid ethyl ester
[0464] a) A mixture of titantetraethoxide (25.07 g, 110 mmol),
(R)-tert.-butylsulfinamide (13.32 g, 110 mmol) and
1-(6-bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-ethanone (28.67
g, 85 mmol, 98% pure) in THF (250 ml) was heated under a nitrogen
atmosphere for 24 hours at 60.degree. C. The cold reaction mixture
was then concentrated to remove ethanol. Dry toluene (2.times.150
ml) was added and removed in vacuo to minimize the content of
ethanol. Finally dry THF (250 ml) was added.
[0465] b) The Reformatsky reagent was prepared in a separate flask:
To a suspension of zinc (17.15 g, 262 mmol) and copper(I) chloride
(1.256 g, 12.68 mmol) in dry THF (20 ml) were added 3 drops of
trimethylchlorosilane under nitrogen to activate the zinc. After 10
minutes ethyl 2-bromo-2,2-difluoroacetate (51.5 g, 254 mmol) was
added slowly by syringe between 25 and 35.degree. C. (Slightly
exothermic with induction period) The reaction mixture was kept in
an ultrasound bath for 45 minutes.
[0466] The sulfoximine solution was cooled to 0.degree. C. and the
Reformatsky reagent b) was quickly added to the sulfoximine
solution a). The cooling bath was removed and stirring was
continued at 50.degree. C. for 4 h.
[0467] The cold reaction mixture was poured onto ice cold aqueous
5% sulfuric acid solution (300 ml) with gentle stirring. The
suspension was diluted with water (150 ml) and TBME (500 to 1000
ml) and was stirred at rt for 30 min (pH about 3-4). The organic
phase was washed thoroughly with plenty of water with
backextraction of the aqueous phase. The organic phase was finally
washed with brine, dried over magnesium sulfate, filtered and
concentrated. The crude product (52.4 g brown-red oil, 65.3% yield)
was used in the next step without purification.
[0468] TLC (cyclohexane/ethyl acetate 2:1): R.sub.f=0.46;
[0469] LC-MS: Rt.sub.H1=1.53 min; (47% purity; ESI+-MS: m/z 559
[(M+H).sup.+,1Br]; 561); main isomer;
[0470] LC-MS: Rt.sub.H1=1.55 min; (11.9% purity; ESI+-MS: m/z 559
[(M+H).sup.+,1Br]; 561); minor isomer.
c)
(R)-3-(6-Bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-3-((R)-2-methyl-prop-
ane-2-sulfinylamino)-butyric acid ethyl ester
[0471] Freshly ground KF (9.78 g, 168 mmol) was added to a solution
of
(R)-3-(6-bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-2,2-difluoro-3-((-
R)-2-methyl-propane-2-sulfinylamino)-butyric acid ethyl ester
(52.34 g, 56.1 mmol, 60% pure) and acetic acid (9.64 ml, 168 mmol)
in THF (200 ml). DMF (200 ml) was added and the suspension was
stirred at rt. After 3 hours the reaction mixture was diluted with
TBME and washed thoroughly with water, sat. sodium bicarbonate
solution, water and brine, dried over magnesium sulfate, filtered
and evaporated. The crude product (35.9 g yellowish-brown oil, 86%
yield, 60% purity) was used in the next step without
purification.
[0472] TLC (cyclohexane/ethyl acetate 2:1): R.sub.f=0.30;
[0473] LC-MS: Rt.sub.H1=1.10 min; (53% purity; ESI+-MS: m/z 445
[(M+H).sup.+,1Br]; 447); main isomer;
[0474] LC-MS: Rt.sub.H1=1.15 min; (7% purity; ESI+-MS: m/z 445
[(M+H).sup.+,1Br]; 447); minor isomer.
d) (R)-2-Methyl-propane-2-sulfinic acid
[(R)-1-(6-bromo-3-fluoro-pyridin-2-yl)-2,2,difluoro-3-hydroxy-1-methyl-pr-
opyl]amide
[0475] To a solution of
(R)-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-3-((R)-2-methyl-propan-
e-2-sulfinylamino)-butyric acid ethyl ester (35.9 g, 48.4 mmol) in
THF (225 ml) was portion wise added lithiumborohydride (2.63 g, 121
mmol) with external cooling. The exothermic reaction was stirred ar
rt for 60 min. Crushed ice and water was added carefully and the
reaction mixture was diluted with TBME and neutralised with 2N HCl
solution. The organic phase was washed with water and brine, dried
over magnesium sulfate in the presence of charcoal, filtered and
evaporated. The crude product (29.74 g brown-yellow sticky
oil-resin) was used in the next step without purification.
[0476] TLC (cyclohexane/ethyl acetate 1:1): R.sub.f=0.30;
[0477] LC-MS: Rt.sub.H1=0.94 min; (83% purity; ESI+-MS: m/z 403
[(M+H).sup.+,1Br]; 405); main isomer;
[0478] LC-MS: Rt.sub.H1=1.15 min; (14% purity; ESI+-MS: m/z 403
[(M+H).sup.+,1Br]; 405); minor isomer.
e)
(R)-3-Amino-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-butan-1-ol
camphersulfonic acid salt
[0479] To a cold solution of (R)-2-methyl-propane-2-sulfinic acid
[(R)-1-(6-bromo-3-fluoro-pyridin-2-yl)-2,2,difluoro-3-hydroxy-1-methyl-pr-
opyl]amide (29.74 g, 61.2 mmol, 83% pure) in methanol (150 ml) was
added HCl/dioxane 4N (59.8 ml, 239 mmol). The reaction mixture was
stirred for 2.5 hours at rt. The solvent was evaporated and to the
residue was added TBME (300 ml) and crushed ice. The organic phase
was extracted with water (3.times.200 ml, pH readjusted to about 2
with each extraction using 2N HCl solution). The aq. phase was
washed with TBME and solid potassium carbonate was added. The free
base was extracted with TBME and dried over magnesium sulfate,
filtered and evaporated. 15.5 g brown oil. LC-MS crude Rt=0.43 min.
(85%, ES+ m/z 299, 301).
[0480] (+)-Campher sulfonic acid salt:
(R)-3-Amino-3-(6-bromo-3-fluoro-pyridin-2-yl)-2,2-difluoro-butan-1-ol
(13 g crude material, 36.52 mmol) and (+)-CSA monohydrate (9.13 g,
36.52 mmol) in acetone (230 ml) was heated until dissolution. The
solution was cooled down to rt and kept 10 hrs at -20.degree. C.
The solid was filtered and washed with ice cold acetone and dried
at 70.degree. C. for 2 hrs in a vacuum oven. 13.66 g white solid.
(theoretical yield: 19.38 g: 70%). LC-MS: Rt=0.45 min. (>98%
purity, ES+m/z 299, 301 weak signal). Chiral HPLC: Chiracel OD-H,
250.times.4.6 mm; heptane-ethanol-methanol 95:3:2, 1 ml/min.,
Rt=14.188 min 90.76%; Rt=16.17 min. 9.2%: e.e. 82%.
[0481] Recrystallization:
[0482] 13.66 g was recrystallised from a mixture of hot acetone
(220 ml) and ethanol (50 ml). Clear solution. The flask was kept at
-20.degree. C. over the weekend. The solid was filtered, washed
with ice cold acetone and dried in a vacuum oven at 70.degree. C.
White solid: 9.31 g. LC-MS Rt=0.45 min. (100% pure, ES+m/z 299,
301). Chiral HPLC: Chiracel OD-H, 250.times.4.6 mm;
heptane-ethanol-methanol 95:3:2, 1 ml/min., Rt=14.205 min 98.21%;
Rt=16.207 min. 1.7%: e.e. 96.4%. Free base: .sup.1H-NMR (400 MHz,
DMSO-d.sub.6): .delta. 7.76-7.70 (m, 2H), 5.29 (br. s, 1H, OH),
3.89-3.70 (dt, 2H, CH2), 1.59 (s, 3H).
Preparation of Substituted Acid Building Block Intermediates
[0483] The substituted acid building blocks were either
commercially available or can be prepared as described hereafter or
in an analogous manner.
Acid-1: 3-Amino-5-(2,2,2-trifluoro-ethoxy)-pyrazine-2-carboxylic
acid
a) 3-Amino-5-(2,2,2-trifluoro-ethoxy)-pyrazine-2-carboxylic acid
methyl ester
[0484] A mixture of 2,2,2-trifluoro-ethanol (6.9 ml, 96 mmol) and
cesium carbonate (1.56 g, 4.8 mmol) was stirred for 20 min,
3-amino-5-chloro-pyrazine-2-carboxylic acid methyl ester
[28643-16-5] (600 mg, 3.2 mmol) was added and the mixture was
stirred at rt for 42 h. To complete the reaction the mixture was
heated to reflux for another 3 h. Saturated aq. NH.sub.4Cl was
added and the mixture was extracted with EtOAc, the combined
organic layers were washed with saturated aq. sodium chloride,
dried with Na.sub.2SO.sub.4 and evaporated. The residue was
purified by chromatography on silica gel (cyclohexane to
cyclohexane/EtOAc 3:7) to provide the title compound as colorless
solid.
[0485] HPLC: Rt.sub.H1=0.83 min; ESIMS [M+H].sup.+=252.2;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 7.66 (s, 1H), 7.60
(br. s, 2H), 5.03 (q, 2H), 3.81 (s, 3H).
b) 3-Amino-5-(2,2,2-trifluoro-ethoxy)-pyrazine-2-carboxylic
acid
[0486] To a solution of
3-amino-5-(2,2,2-trifluoro-ethoxy)-pyrazine-2-carboxylic acid
methyl ester (400 mg, 1.59 mmol) in THF (20 ml) was added 1N sodium
hydroxide (2.5 ml, 2.5 mmol) and the mixture was stirred at room
temperature over night. To the mixture were added 1N HCl (2.39 ml,
2.39 mmol) after stirring for 5 min toluene was added and the
solvents were evaporated to provide the title compound together
with sodium chloride as an off-white solid. The mixture was used
for coupling reactions without further purification.
[0487] HPLC: Rt.sub.H1=0.71 min; ESIMS [M+H].sup.+=238.2;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 7.46 (s, 1H), 4.97 (q,
2H).
Acid-2: 3-Amino-5-(2,2-difluoro-ethoxy)-pyrazine-2-carboxylic
acid
[0488] The title compound was prepared by an analogous procedure to
Acid-1 using 2,2-difluoro-ethanol instead of
2,2,2-trifluoro-ethanol [Acid-1 step a)].
[0489] HPLC: Rt.sub.H2=0.60 min; ESIMS [M+H].sup.+=220.2;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 12.51 (br. s, 1H),
7.62 (s, 1H), 6.43 (tt, 1H), 4.59 (td, 2H).
Acid-3: 3-Amino-5-(3-fluoro-propoxy)-pyrazine-2-carboxylic acid
[0490] The title compound was prepared by an analogous procedure to
Acid-1 using 3-fluoro-propan-1-ol instead of
2,2,2-trifluoro-ethanol [Acid-1 step a)] and lithium hydroxide
instead of sodium hydroxide [Acid-1 step b)].
[0491] HPLC: Rt.sub.H1=0.60 min; ESIMS [M+H].sup.+=216.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 8.98 (br. s, 1H), 7.19
(s, 1H), 6.82 (br. s, 1H), 4.65 (t, 1H), 4.53 (t, 1H), 4.32 (t,
2H), 2.20-1.99 (m, 2H).
Acid-4: 3-Amino-5-(3-fluoro-propoxy)-pyrazine-2-carboxylic acid
[0492] The title compound was prepared by an analogous procedure to
Acid-1 using 2-methoxy-ethanol instead of 2,2,2-trifluoro-ethanol
[Acid-1 step a)].
[0493] HPLC: Rt.sub.H1=0.53 min; ESIMS [M+H].sup.+=214.2;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 12.49 (br. s, 1H),
7.54 (br. s, 2H), 7.51 (s, 1H), 4.49-4.33 (m, 2H), 3.71-3.60 (m,
2H), 3.30 (s, 3H).
Acid-5: 3-Amino-5-(2-fluoro-ethoxy)-pyrazine-2-carboxylic acid
a) 3-Amino-4-oxy-pyrazine-2-carboxylic acid methyl ester
[0494] To a solution of 3-amino-pyrazine-2-carboxylic acid methyl
ester [16298-03-6] (15 g, 98 mmol) in CHCl.sub.3 (245 ml) was added
mCPBA (26.6 g, 108 mmol) and the resulting mixture was heated up to
reflux for 40 min. To complete the reaction, more mCPBA (2.5 g) was
added and the reaction was heated to reflux for another 40 min. The
mixture was diluted in DCM/Chlorofom (1/1) and then saturated aq.
NaHCO.sub.3 was added. The organic layer was separated and the
aqueous layer was extracted several times with DCM/Chloroform
(1/1). The combined organic layers were dried with
Na.sub.2SO.sub.4, filtered and evaporated to give a yellow solid.
(12.6 g, 68% yield, 90% purity)
[0495] HPLC: Rt.sub.H1=0.33 min; ESIMS [M+H].sup.+=170.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 8.48 (d, 1H), 7.88 (d,
1H), 7.70 (br. s, 2H), 3.89 (s, 3H).
b) 3-Acetylamino-5-oxo-4,5-dihydro-pyrazine-2-carboxylic acid
methyl ester
[0496] A solution of 3-amino-4-oxy-pyrazine-2-carboxylic acid
methyl ester (11.3 g, 66.8 mmol) in Ac.sub.2O (150 ml, 1590 mmol)
and AcOH (200 ml) was heated to 120.degree. C. for 2 h, then the
reaction was cooled to rt, the solvent was evaporated and
co-evaporated with toluene. The resulting crude material was
directly used in the next step without further purification.
[0497] HPLC: Rt.sub.H1=0.45 min; ESIMS [M+H].sup.+=212.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 12.55 (br. s, 1H),
11.04-10.75 (m, 1H), 7.76 (br. s, 1H), 3.81 (s, 3H), 2.25 (s,
3H).
c) 3-Acetylamino-5-(2-fluoro-ethoxy)-pyrazine-2-carboxylic acid
methyl ester
[0498] To a solution of
3-acetylamino-5-oxo-4,5-dihydro-pyrazine-2-carboxylic acid methyl
ester (300 mg, 1.136 mmol, 80% purity) in dry THF (8 ml) under
argon were added triphenylphoshine (119 mg, 0.455 mmol) and diethyl
azodicarboxylate (DEAD, 0.072 ml, 0.455 mmol) at -10.degree. C. The
reaction was stirred at -10.degree. C. for 15 min and then
2-fluoro-ethanol (0.033 ml, 0.568 mmol) was added. The reaction was
stirred at rt for 15 min. To complete the reaction, more
triphenylphoshine (119 mg, 0.455 mmol) and DEAD (0.072 ml, 0.455
mmol) were added at -10.degree. C. and the resulting mixture was
stirred at -10.degree. C. for 15 min before the addition of
2-fluoro-ethanol (0.033 ml, 0.568 mmol). The reaction was stirred
for 100 min. More triphenylphoshine (119 mg, 0.455 mmol) and DEAD
(0.072 ml, 0.455 mmol) were added at -10.degree. C. and the
resulting mixture was stirred at -10.degree. C. for 15 min before
the addition of 2-fluoroethanol (0.033 ml, 0.568 mmol). The
reaction was stirred for another 2 h. Saturated aq. NaHCO.sub.3 was
added and the mixture was extracted with EtOAc, the combined
organic layers were washed with aq. sodium chloride, filtered and
dried with Na.sub.2SO.sub.4 and evaporated. The residue was
purified by chromatography on silica gel (DCM to DCM/EtOAc 9:1) to
provide the title compound as yellow oil (300 mg).
[0499] HPLC: Rt.sub.H2=0.63 min; ESIMS [M+H].sup.+=258.4;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 10.70 (s, 1H), 8.14
(s, 1H), 4.98-4.81 (m, 1H), 4.77-4.72 (m, 1H), 4.68-4.63 (m, 1H),
4.60-4.56 (m, 1H), 3.79 (s, 3H), 2.21 (s, 3H).
d) 3-Amino-5-(2-fluoro-ethoxy)-pyrazine-2-carboxylic acid methyl
ester
[0500] To a mixture of
3-acetylamino-5-(2-fluoro-ethoxy)-pyrazine-2-carboxylic acid methyl
ester (330 mg, 0.962 mmol) in dry MeOH (12 ml) was added sodium
methoxide (52.0 mg, 0.962 mmol) at 0.degree. C. The resulting
suspension was stirred at rt for 1 h. Saturated aq. NH.sub.4CI, was
added and then mixture was extracted with EtOAc. The combined
organic layers were dried with Na.sub.2SO.sub.4, filtered and
evaporated. The residue was purified by chromatography on silica
gel (DCM to DCM/EtOAc 9:1) to provide the title compound as white
solid (176 mg).
[0501] HPLC: Rt.sub.H2=0.62 min; ESIMS [M+H].sup.+=216.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 7.56 (s, 1H), 7.50
(br. s, 2H), 4.87-4.79 (m, 1H), 4.74-4.67 (m, 1H), 4.62-4.55 (m,
1H), 4.53-4.45 (m, 1H), 3.80 (s, 3H).
e) 3-Amino-5-(2-fluoro-ethoxy)-pyrazine-2-carboxylic acid
[0502] To a solution of
3-amino-5-(2-fluoro-ethoxy)-pyrazine-2-carboxylic acid methyl ester
(176 mg, 0.818 mmol) in THF (6.8 ml) was added a solution of 1M
NaOH (900 .mu.l, 0.900 mmol). The reaction was stirred at rt for 48
h. A solution of 1M HCl (1096 .mu.L, 1.096 mmol) was added, the
mixture was evaporated to dryness and then co-evaporated with
toluene to give a light purple solid (212 mg). The crude material
was used directly for the coupling reactions.
[0503] HPLC: Rt.sub.H2=0.50 min; ESIMS [M+H].sup.+=202.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 12.52 (br. s, 1H),
7.56 (br. s, 2H), 7.54 (s, 1H), 4.83 (dd, 1H), 4.71 (dd, 1H),
4.60-4.54 (m, 1H), 4.50 (dd, 1H).
Acid-6: 3-Amino-5-(2-chloro-ethoxy)-pyrazine-2-carboxylic acid
[0504] The title compound was prepared by an analogous procedure to
Acid-5 using 2-chloro-ethanol instead of 2-fluoro-ethanol [Acid-5
step c)], adding more 1M NaOH (200 .mu.l, 0.200 mmol) after 48 h of
stirring in step e).
[0505] HPLC: Rt.sub.H2=0.62 min; ESIMS [M+H].sup.+=218.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 12.45 (br. s, 1H),
7.69 (br s, 2H), 7.48 (s, 1H), 4.59-4.46 (m, 2H), 4.01-3.93 (m,
2H).
Acid-7: 3-Amino-5-penta-deutero-ethoxy-pyrazine-2-carboxylic
acid
[0506] The title compound was prepared by an analogous procedure to
Acid-5 using penta-deutero-ethanol instead of 2-fluoro-ethanol
[Acid-5 step c)], applying a reaction time of 24 h after the second
addition of triphenylphosphine, DEAD and penta-deutero-ethanol
instead of 1 h in step c).
[0507] HPLC: Rt.sub.H2=0.58 min; ESIMS [M+H].sup.+=189.1
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 12.43 (br. s, 1H),
7.52 (br. s, 2H), 7.46 (s, 1H).
Acid-8:
3-Amino-5-[2-(tert-butoxycarbonyl-methyl-amino)-ethoxy]-pyrazine-2-
-carboxylic acid
[0508] The title compound was prepared by an analogous procedure to
Acid-5 using tert-butyl 2-hydroxyethyl-methyl-carbamate
[57561-39-4] instead of 2-fluoro-ethanol [Acid-5 step c)], applying
a reaction time of 24 h after the third addition of
triphenylphosphine, DEAD and 2-hydroxyethyl-methyl-carbamate
instead of 2 h in step c). In step e) a second and a third addition
of 1M NaOH (106 .mu.l, 0.106 mmol) after 72 h and after 144 h were
done, involving the quenching of 1M HCl (539 .mu.l, 0.539
mmol).
[0509] HPLC: Rt.sub.H2=0.82 min; ESIMS [M+H].sup.+=313.1
.sup.1H-NMR (400 MHz, DMSO-d.sub.6, main rotamer): .delta. 7.32
(br. s, 1H), 4.34 (br. s, 2H), 3.55 (br. s, 2H), 2.83 (s, 3H), 1.29
(br. s, 9H).
Acid-9:
3-(di-tert-Butoxycarbonyl-amino)-5-difluoromethyl-pyrazine-2-carbo-
xylic acid
a) 3-Amino-5-vinyl-pyrazine-2-carboxylic acid methyl ester
[0510] To a mixture of 3-amino-5-chloro-pyrazine-2-carboxylic acid
methyl ester (GB 1248146, 161 mg 0.86 mmol), tributyl(vinyl)tin
(0.352 ml, 1.204 mmol) and lithium chloride (102 mg, 2.498 mmol) in
DMF (4 ml) was added PdCl.sub.2(PPh.sub.3).sub.2 (30.2 mg, 0.043
mmol) and the mixture was heated to 85.degree. C. for 2.5 h. After
cooling to room temperature water was added and the mixture was
extracted with EtOAc, the combined organic layers were washed with
water and half saturated aq. NaCl, dried with Na.sub.2SO.sub.4 and
evaporated. The residue was purified by chromatography on silica
gel (cyclohexane to cyclohexane/EtOAc 1:9) to provide the title
compound as yellow solid.
[0511] HPLC: Rt.sub.H4=0.71 min; ESIMS [M+H].sup.+=179.9;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 8.04 (s, 1H), 7.35
(br. s, 1H), 6.75 (dd, 1H), 6.38 (d, 1H), 5.70 (d, 1H), 3.84 (s,
3H).
b) 3-(di-tert-Butoxycarbonyl-amino)-5-vinyl-pyrazine-2-carboxylic
acid methyl ester
[0512] To an ice cooled solution of
3-amino-5-vinyl-pyrazine-2-carboxylic acid methyl ester (1.28 g,
7.14 mmol) in DCM (45 ml) was added Boc.sub.2O (8.58 g, 39.3 mmol)
and the mixture was stirred at room temperature for 30 min, then
the mixture was heated to 40.degree. C. for 4 h. After cooling to
room temperature water was added and the mixture was extracted with
DCM. The combined organic layers were washed with 0.5N HCl and
saturated aq. NaCl, dried with Na.sub.2SO.sub.4 and evaporated. The
residue was purified by chromatography on silica gel
(cyclohexane+5% NEt.sub.3 to EtOAc+5% NEt.sub.3) to provide the
title compound as yellow solid.
[0513] HPLC: Rt.sub.H1=1.15 min; ESIMS [M-Boc].sup.+=280.3;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 8.93 (s, 1H), 7.00
(dd, 1H), 6.51 (dd, 1H), 5.86 (dd, 1H), 3.88 (s, 3H), 1.34 (s,
18H).
c) 3-(di-tert-Butoxycarbonyl-amino)-5-formyl-pyrazine-2-carboxylic
acid methyl ester
[0514] A mixture of
3-(di-tert-butoxycarbonyl-amino)-5-vinyl-pyrazine-2-carboxylic acid
methyl ester (1 g, 2.64 mmol) and sodium bicarbonate (0.332 g, 3.95
mmol) in DCM (45 ml) and MeOH (15 ml) was cooled to -78.degree. C.
and purged with oxygen for 5 min. The reaction mixture was treated
with ozone for 40 min until the mixture turned blue. The reaction
mixture was purged with oxygen for 10 min and with nitrogen for 10
min, then dimethyl sulfide (0.487 ml, 6.59 mmol) was added at
-78.degree. C. and the mixture was allowed to warm to room
temperature. The mixture was diluted with DCM and washed with 10%
aq. sodium thiosulfate. The aq. layer was extracted with DCM and
the combined organic layers were dried with Na.sub.2SO.sub.4 and
evaporated to provide the title compound as yellow oil. The
compound was used for the next step without further
purification.
[0515] .sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 10.07 (s, 1H),
9.24 (s, 1H), 3.94 (s, 3H), 1.36 (s, 18H).
d)
3-(di-tert-Butoxycarbonyl-amino)-5-difluoromethyl-pyrazine-2-carboxylic
acid methyl ester
[0516] To an ice cooled solution of
3-(di-tert-butoxycarbonyl-amino)-5-formyl-pyrazine-2-carboxylic
acid methyl ester (550 mg, 1.44 mmol) in DCM (20 ml) was added
dropwise within 1 h Deoxofluor (50% in THF, 0.798 ml, 4.33 mmol).
Stirring was continued at 0.degree. C. for 2.5 h then the reaction
mixture was allowed to room temperature over night. Saturated aq.
sodium bicarbonate was added and the mixture extracted with EtOAc,
the combined organic layers were washed with sat. aq. sodium
chloride, dried with Na.sub.2SO.sub.4 and evaporated. The residue
was purified by chromatography on silica gel (cyclohexane+5%
NEt.sub.3 to cyclohexane+5% NEt.sub.3/EtOAc+5% NEt.sub.3 1:1) to
provide the title compound as colorless solid.
[0517] HPLC: Rt.sub.H1=1.14 min; ESIMS [2M+Na].sup.+=829.6;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 9.14 (s, 1H), 7.26 (t,
1H, CHF2), 3.92 (s, 3H), 1.33 (s, 18H).
e)
3-(di-tert-Butoxycarbonyl-amino)-5-difluoromethyl-pyrazine-2-carboxylic
acid
[0518] To a solution of
3-(di-tert-butoxycarbonyl-amino)-5-difluoromethyl-pyrazine-2-carboxylic
acid methyl ester (75 mg, 0.186 mmol) in THF (2 ml) was added
dropwise 1N NaOH (0.205 ml, 0.205 mmol) and the reaction mixture
was stirred for 1.5 h. To the mixture was added 1N HCl (0.186 ml,
0.186 mmol) after stirring for 5 min toluene was added and the
solvents were evaporated to provide the title compound together
with sodium chloride as colorless solid. The mixture was used for
coupling reactions without further purification.
[0519] HPLC: Rt.sub.H4=0.89 min; ESIMS [M-Boc].sup.+=290.0;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 14.30 (br. s, 1H),
9.10 (s, 1H), 7.25 (t, 1H, CHF2), 1.33 (s, 18H).
Acid-10: 3-Amino-5-(3-methoxy-prop-1-ynyl)-pyridine-2-carboxylic
acid
a) 3-Amino-5-(3-methoxy-prop-1-ynyl)-pyridine-2-carboxylic acid
methyl ester
[0520] To a solution of 3-methoxy-propyne (421 mg, 6 mmol),
bis(triphenylphosphine)palladium(II) chloride (84 mg, 0.12 mmol),
copper(I) iodide (23 mg, 0.12 mmol) and NEt.sub.3 (1.17 ml, 8.4
mmol) in THF (10 ml) under Argon was added
3-amino-5-bromo-pyridine-2-carboxylic acid methyl ester (277 mg,
1.2 mmol) and the mixture was heated to 80.degree. C. for 5 h. At
0.degree. C. water (12 ml) was added and the mixture was extracted
with EtOAc, the combined organic layers were washed with
half-saturated aq. sodium chloride, dried with Na.sub.2SO.sub.4 and
evaporated. The residue was purified by chromatography on silica
gel (cyclohexane to cyclohexane/EtOAc 1:4) to provide the title
compound as orange solid.
[0521] HPLC: Rt.sub.H1=0.67 min; ESIMS [M+H].sup.+=221.1;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 7.85 (d, 1H),
7.33-7.22 (m, 1H), 6.77 (s, 2H), 4.35 (s, 2H), 3.80 (s, 3H), 3.33
(s, 3H).
b) 3-Amino-5-(3-methoxy-prop-1-ynyl)-pyridine-2-carboxylic acid
[0522] To a solution of
3-amino-5-(3-methoxy-prop-1-ynyl)-pyridine-2-carboxylic acid methyl
ester (263 mg, 1.2 mmol) in THF (6 ml) was added 1N lithium
hydroxide (1.32 ml, 1.32 mmol) at 0.degree. C. and the mixture was
stirred at room temperature for 2 h. To the mixture was added 1N
HCl (1.2 ml, 1.2 mmol) at 0.degree. C., after stirring for 5 min
toluene was added and the solvents were evaporated to provide the
title compound together with lithium chloride as an off-white
solid. The mixture was used for coupling reactions without further
purification.
[0523] HPLC: Rt.sub.H1=0.45 min; ESIMS [M+H].sup.+=207.2;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 7.84 (s, 1H), 7.30 (s,
1H), 6.92 (br. s., 1H), 4.35 (s, 2H), 3.33 (s, 3H).
Acid-11:
3-Chloro-5-[3-(tetrahydro-pyran-2-yloxy)-prop-1-ynyl)-pyridine-2--
carboxylic acid
[0524] The title compound was prepared by an analogous procedure to
Acid-xx using 5-bromo-3-chloro-pyridine-2-carboxylic acid methyl
ester instead of 3-amino-5-bromo-pyridine-2-carboxylic acid methyl
ester and 2-prop-2-ynyloxy-tetrahydro-pyran instead of
3-methoxy-propyne [Acid-xx step a)].
[0525] HPLC: Rt.sub.H2=0.68 min; ESIMS [M+H].sup.+=296.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 14.02 (br. s, 1H),
8.65 (s, 1H), 8.26 (s, 1H), 4.84 (br. s, 1H), 4.66-4.36 (m, 2H),
3.85-3.64 (m, 1H), 3.58-3.41 (m, 1H), 1.80-1.61 (m, 2H), 1.60-1.41
(m, 4H)
Acid-12: 3-Chloro-5-(3-methoxy-prop-1-ynyl)-pyridine-2-carboxylic
acid
[0526] To a solution of 3-methoxy-propyne (421 mg, 6 mmol),
bis(triphenylphosphine)palladium(II) chloride (84 mg, 0.12 mmol),
copper(I) iodide (23 mg, 0.12 mmol) and NEt.sub.3 (1.17 ml, 8.4
mmol) in THF (10 ml) under Argon was added
3-chloro-5-bromo-pyridine-2-carboxylic acid methyl ester (284 mg,
1.2 mmol) and the mixture was heated to 80.degree. C. for 5 h. At
0.degree. C. water (12 ml) was added and the mixture was extracted
with EtOAc. The aq. Phase was acidified to pH 1 by addition of 1N
HCl, extracted with DCM. The combined DCM extracts were washed with
half-saturated aq. sodium chloride, dried with Na.sub.2SO.sub.4 and
evaporated to provide the title compound as an off-white solid,
which was used for coupling reactions without further
purification.
[0527] HPLC: Rt.sub.H1=0.49 min; ESIMS [M+H].sup.+=226.3;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 14.02 (br. s., 1H),
8.64 (s, 1H), 8.24 (s, 1H), 4.39 (s, 2H), 3.33 (s, 3H).
Acid-13: 3-Amino-5-(3-hydroxy-prop-1-ynyl)-pyridine-2-carboxylic
acid
a)
3-Amino-543-(tert-butyl-dimethyl-silanyloxy)-prop-1-ynyl)-pyridine-2-ca-
rboxylic acid methyl ester
[0528] The title compound was prepared by an analogous procedure to
Acid-10 using tert-butyl-dimethyl-prop-2-ynyloxy-silane instead of
3-methoxy-propyne [Acid-10 step a)].
[0529] HPLC: Rt.sub.H1=1.23 min; ESIMS [M+H].sup.+=321.2;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 7.81 (s, 1H), 7.26 (d,
1H), 6.78 (br. s, 2H), 4.57 (s, 2H), 3.79 (s, 3H), 0.89 (s, 9H),
0.12 (s, 6H).
b) 3-Amino-5-(3-hydroxy-prop-1-ynyl)-pyridine-2-carboxylic acid
methyl ester
[0530] To a solution of
3-amino-543-(tert-butyl-dimethyl-silanyloxy)-prop-1-ynyl)-pyridine-2-carb-
oxylic acid methyl ester (711 mg, 2.22 mmol) in DCM (6 ml) was
added 10.2 ml TFA (133 mmol) at 0.degree. C. and the mixture was
stirred at room temperature for 17 h. To the mixture was added
toluene (18 ml) and the solvents were evaporated. The residue was
dissolved in EtOAc (66 ml) and washed with aq. 1M Na.sub.2CO.sub.3
solution, the aq. Phase was extracted back with EtOAc. The combined
organic layers were washed with half-saturated aq. sodium chloride,
dried with Na.sub.2SO.sub.4 and evaporated. The residue was
purified by chromatography on silica gel (DCM to DCM/MeOH 94:6) to
provide the title compound as an off-white solid.
[0531] HPLC: Rt.sub.H1=0.50 min; ESIMS [M+H].sup.+=207.1;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 7.82 (s, 1H), 7.24 (s,
1H), 6.77 (br s, 2H), 5.43 (br. s, 1H), 4.32 (s, 2H).
c) 3-Amino-5-(3-hydroxy-prop-1-ynyl)-pyridine-2-carboxylic acid
[0532] To a solution of
3-amino-5-(3-hydroxy-prop-1-ynyl)-pyridine-2-carboxylic acid methyl
ester (297 mg, 1.44 mmol) in THF (10 ml) was added 1N lithium
hydroxide and the mixture was vigorously stirred at room
temperature for 4.5 h. To the mixture was added 4N HCl (0.47 ml,
1.87 mmol), after dilution with toluene the solvent was evaporated,
the residue was suspended in toluene and evaporated (twice). The
residue was suspended in TBME/hexane, filtered and the solid dried
under reduced pressure at 50.degree. C. to provide the title
compound together with lithium chloride as a brown solid. The
mixture was used for coupling reactions without further
purification.
[0533] HPLC: Rt.sub.H5=1.93 min; ESIMS [M+H].sup.+=193.0;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 7.83 (s, 1H), 7.28 (s,
1H), 6.94 (br. s, 1H), 4.33 (s, 2H).
Acid-14: 3-Amino-5-difluoromethyl-pyridine-2-carboxylic acid
a) 5-Difluoromethyl-3-nitro-pyridine-2-carboxylic acid tert-butyl
ester
[0534] The title compound was prepared by an analogous reaction
sequence to Acid-9 using 5-bromo-3-nitro-pyridine-2-carboxylic acid
instead of 3-amino-5-chloro-pyrazine-2-carboxylic acid methyl ester
in step a) and omitting step b).
[0535] HPLC: Rt.sub.H1=1.07 min; ESIMS [M+H].sup.+=275.3;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 9.18 (s, 1H), 8.82 (s,
1H), 7.31 (t, 1H, CHF2), 1.55 (s, 9H).
b) 5-Difluoromethyl-3-nitro-pyridine-2-carboxylic acid
[0536] In a mixture of 5 ml DCM and 2.5 ml TFA was dissolved 345 mg
(1.26 mmol) 5-difluoromethyl-3-nitro-pyridine-2-carboxylic acid
tert-butyl ester and the reaction mixture was stirred for 4 h.
Toluene was added and the solvents were evaporated to provide the
title compound as colorless solid.
[0537] HPLC: Rt.sub.H1=0.31 min; ESIMS [2M-H].sup.-=435.3;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 14.59 (br. s, 1H),
9.16 (s, 1H), 8.80 (s, 1H), 7.31 (t, 1H, CHF2).
c) 3-Amino-5-difluoromethyl-pyridine-2-carboxylic acid
[0538] To a solution of 265 mg (1.22 mmol)
5-difluoromethyl-3-nitro-pyridine-2-carboxylic acid in EtOH was
added 50 mg Raney-Nickel (Degussa B113W) and the reaction mixture
was kept shaking under a hydrogen atmosphere for 16 h. The catalyst
was filtered off (Celite) and washed with EtOH and the filtrate was
evaporated to provide the title compound as off-white solid.
[0539] HPLC: Rt.sub.H1=0.34 min; ESIMS [M+H].sup.+=189.2;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 7.98 (s, 1H), 7.39 (s,
1H), 7.09 (t, 1H, CHF2), 7.02 (br. s, 2H).
Acid-15: 3-Chloro-5-(2,2-difluoro-ethoxy)-pyridine-2-carboxylic
acid
a) 3-Chloro-5-(2,2-difluoro-ethoxy)-pyridine-2-carbonitrile
[0540] To a solution of 3-chloro-5-hydroxy-pyridine-2-carbonitrile
[1262860-70-7] (0.200 g, 1.23 mmol) in THF (15 ml) was added at
0.degree. C. 2,2-difluoro-ethanol (0.123 g, 1.48 mmol) and
triphenylphosphine (0.484 g, 1.84 mmol). After stirring for 10 min
at 0.degree. C. DIAD (0.373 g, 1.84 mmol) was added and the
reaction mixture was stirred for 2 h at 0.degree. C. followed by 16
h at 25.degree. C. The reaction mixture was concentrated and the
title compound was obtained after CombiFlash chromatography on
silica gel (hexane/EtOAc 20:1 to 1:1) as a colorless oil.
[0541] TLC (hexane-EtOAc 1:1): Rf=0.61; UPLC Rt.sub.H6=0.965 min;
ESIMS: 217 [(M-H).sup.-]; .sup.1H-NMR (400 MHz, CDCl.sub.3):
.delta. 8.31 (d, 1H), 7.32 (d, 1H), 6.12 (tt, 1H), 4.31 (dt,
2H).
b) 3-Chloro-5-(2,2-difluoro-ethoxy)-pyridine-2-carboxylic acid
[0542] To a solution of
3-Chloro-5-(2,2-difluoro-ethoxy)-pyridine-2-carbonitrile (0.202 g,
0.878 mmol) in dioxane (4 ml) was added 4N NaOH (2.2 ml, 8.8 mmol)
and the resulting reaction mixture was stirred for 28 h at
85.degree. C. The reaction mixture was diluted with water and
extracted with EtOAc. The aqueous phase was acidified with 4N HCl
and evaporated to dryness. The title compound was extracted with
DCM/MeOH (9/1), pushed through a plug of Celite and was obtained
after evaporation as a light yellow solid.
[0543] UPLC Rt.sub.H6=0.655 min; ESIMS: 236 [(M-H).sup.-];
.sup.1H-NMR (400 MHz, CD.sub.3OD): .delta. 8.31 (d, 1H), 7.68 (d,
1H), 6.23 (tt, 1H), 4.44 (dt, 2H); .sup.19F-NMR (400 MHz,
CD.sub.3OD) 128.0 (dt, 2F).
Acid-16: 3-Chloro-5-fluoromethoxy-pyridine-2-carboxylic acid
a) 2,3-Dichloro-5-fluoromethoxy-pyridine
[0544] To a solution of 5,6-dichloro-pyridin-3-ol [11860-92-9] (500
mg, 3.05 mmol) and K.sub.2CO.sub.3 (632 mg, 4.57 mmol) in dry ACN
(12 ml) was added fluoro-iodomethane (1.156 ml, 9.15 mmol) at
0.degree. C. The light yellow suspension was stirred for 5 min at
0.degree. C. and then heated up to 120.degree. C. for 30 min.
Saturated aq. NH.sub.4Cl was added, followed by EtOAc. The organic
layer was separated and the aqueous layer was extracted twice with
EtOAc. The combined organic layers were washed with brine, dried
with Na.sub.2SO.sub.4, filtered and evaporated to give a brown oil.
The crude material was directly used in the next step without
further purification.
[0545] HPLC: Rt.sub.H2=0.95 min; ESIMS [M+H].sup.+=198.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 8.31 (dd, 1H), 8.07
(d, 1H), 6.05 (s, 1H), 5.91 (s, 1H).
b) 3-Chloro-5-fluoromethoxy-pyridine-2-carbonitrile
[0546] To a solution of 2,3-dichloro-5-fluoromethoxy-pyridine (1.18
g, 6.02 mmol) in dry DMF (14.00 ml) were added Zinc cyanide (0.341
g, 2.90 mmol) and Zinc powder (3.94 mg, 0.060 mmol). The suspension
was flushed with Argon (3.times.). Then
tetrakis(triphenylphosphine)palladium(0) (0.570 g, 0.494 mmol) was
added. The reaction was heated to 145.degree. C. for 2 h. Water was
added and the aqueous layer was extracted twice with Et.sub.2O. The
combined organic layers were washed with brine, dried with
Na.sub.2SO.sub.4, filtered and evaporated. The residue was purified
by chromatography on silica gel (cyclohexane to cyclohexane/EtOAc
7:3) to provide the title compound as yellow oil (515 mg).
[0547] HPLC: Rt.sub.H2=0.81 min; ESIMS [M+H].sup.+=187.0;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 8.61 (s, 1H), 8.16 (s,
1H), 6.15 (s, 1H), 6.02 (s, 1H).
c) 3-Chloro-5-fluoromethoxy-pyridine-2-carboxylic acid
[0548] To a solution of
3-chloro-5-fluoromethoxy-pyridine-2-carbonitrile (80 mg, 0.429
mmol) in EtOH (2.4 ml) was added 1M NaOH (1.21 ml, 1.201 mmol) and
the resulting solution was stirred at 70.degree. C. over night. To
complete the reaction, more 1M NaOH (1.2 ml, 1.201 mmol) was added
and the reaction was stirred at 70.degree. C. for 8 h. More 1M NaOH
(1.2 ml, 1.201 mmol) was added and the reaction was stirred over
night. Then 1M HCl (3.45 ml, 3.45 mmol) was added. The aqueous
layer was extracted twice with EtOAc. The combined organic layers
were dried with Na.sub.2SO.sub.4, filtered and evaporated to give a
light pink solid. Mixture of 80 mg, 35% of
3-chloro-5-fluoromethoxy-pyridine-2-carboxylic acid, 38% of
3-chloro-5-ethoxy-pyridine-2-carboxylic acid.
3-Chloro-5-fluoromethoxy-pyridine-2-carboxylic acid
[0549] HPLC: Rt.sub.H2=0.42 min; ESIMS [M+H].sup.+=206.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 13.36 (br. s, 1H),
8.29 (d, 1H), 7.66 (d, 1H), 6.09 (s, 1H), 5.96 (s, 1H).
3-Chloro-5-ethoxy-pyridine-2-carboxylic acid
[0550] HPLC: Rt.sub.H2=0.59 min; ESIMS [M+H].sup.+=202.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 13.66 (br. s, 1H),
8.45 (d, 1H), 8.29 (d, 1H), 4.21 (q, 2H), 1.36 (t, 3H).
[0551] The crude mixture of acids was used for the couling reaction
without further purification.
Acid-17: 3-Amino-5-(2-methoxy-ethyl)-pyrazine-2-carboxylic acid
a) 3-Amino-5-((Z)-2-ethoxy-vinyl)-pyrazine-2-carboxylic acid methyl
ester
[0552] A mixture of 3-amino-5-chloro-pyrazine-2-carboxylic acid
methyl ester [28643-16-5] (2 g, 10.66 mmol), lithium chloride
(1.582 g, 37.3 mmol), Pd(PPh.sub.3).sub.2Cl.sub.2 (0.748 g, 1.066
mmol) and tributyl-((Z)-2-ethoxy-vinyl)-stannane (6.42 ml, 19.19
mmol) in DMF (104 ml) under argon was heated at 80.degree. C. bath
temperature for 1.5 h. A saturated. aq. NH.sub.4Cl was added and
the mixture was extracted with MTBE, then once with EtOAc/THF 3/1.
The combined organic layer was washed with brine, dried with
Na.sub.2SO.sub.4, filtered and concentrated under reduced pressure.
The residue was purified by chromatography on silica gel
(cyclohexane to cyclohexane/EtOAc 1:9) to provide the title
compound as yellow oil (1.96 g).
[0553] HPLC: Rt.sub.H2=0.69 min; ESIMS [M+H].sup.+=225.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 8.42 (s, 1H), 7.18
(br. s, 2H), 6.88 (d, 1H), 5.23 (d, 1H), 4.15 (q, 2H), 3.82 (s,
3H), 1.32 (t, 3H).
b) 3-Amino-5-(2,2-dimethoxy-ethyl)-pyrazine-2-carboxylic acid
methyl ester
[0554] A solution of
3-amino-5-((Z)-2-ethoxy-vinyl)-pyrazine-2-carboxylic acid methyl
ester (220 mg, 0.986 mmol) in 3M HCl in MeOH (210 .mu.l, 6.90 mmol)
was heated at 55.degree. C. over night. A solution of 10% of
NaHCO.sub.3 was added the mixture was extracted with EtOAc. The
combined organic layer was dried with Na.sub.2SO.sub.4, filtered
and concentrated under reduced pressure to obtain a brown solid
(141 mg). The crude material was directly used in the next step
without further purification.
[0555] HPLC: Rt.sub.H1=0.59 min; ESIMS [M+H].sup.+=242.2.
c) 3-Amino-5-(2-methoxy-vinyl)-pyrazine-2-carboxylic acid methyl
ester
[0556] To a solution of
3-amino-5-(2,2-dimethoxy-ethyl)-pyrazine-2-carboxylic acid methyl
ester (300 mg, 1.244 mmol) and Et.sub.3N (1.213 ml, 8.70 mmol) in
DCM (10 ml) at -10.degree. C. was added dropwise timethylsilyl
trifluoromethanesulfonate (0.809 ml, 4.48 mmol). The reaction
mixture was stirred at room temperature for 100 min. A saturated
solution of NaHCO.sub.3 was added and the mixture was extracted
twice with DCM. The combined organic layers were washed with
NH.sub.4Cl solution and brine, dried with Na.sub.2SO.sub.4,
filtered and concentrated under reduced pressure to obtain a brown
oil (560 mg). The resulting crude material (mixture of E and Z) was
directly used in the next step without further purification.
[0557] HPLC: Rt.sub.H1=0.63 min; ESIMS [M+H].sup.+=210.1.
d) 3-Amino-5-(2-methoxy-ethyl)-pyrazine-2-carboxylic acid methyl
ester
[0558] A solution of
3-amino-5-(2-methoxy-vinyl)-pyrazine-2-carboxylic acid methyl ester
(260 mg, 1.24 mmol) and Pd/C 10% (50 mg) in EtOH (10 ml) was
stirred at rt and under an atmosphere of hydrogen for 17 h. To
complete the reaction, more Pd/C 10% (84 mg) was added and the
reaction was stirred under an atmosphere of hydrogen for 37 h. The
suspension was filtered off and washed with EtOH and then residual
solution was evaporated. The residue was purified by chromatography
on silica gel (DCM to DCM/MeOH 9:1) to provide the title compound
as yellow solid (147 mg).
[0559] HPLC: Rt.sub.H2=0.54 min; ESIMS [M+H].sup.+=212.2;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 7.84 (s, 1H), 7.31
(br. s, 2H), 3.83 (s, 3H), 3.68 (t, 2H), 3.23 (s, 3H), 2.87 (t,
3H).
e) 3-Amino-5-(2-methoxy-ethyl)-pyrazine-2-carboxylic acid
[0560] To a solution of
3-amino-5-(2-methoxy-ethyl)-pyrazine-2-carboxylic acid methyl ester
(147 mg, 0.696 mmol) in THF (14 ml) was added 1M NaOH (1.74 ml,
1.74 mmol) and the reaction mixture was stirred at room temperature
for 2 h. 1M HCl (1.601 ml, 1.601 mmol) was added to the reaction
mixture. The resulting mixture was evaporated and co-evaporated
with toluene. The resulting crude material was directly used in the
coupling step without further purification.
[0561] HPLC: Rt.sub.H2=0.41 min; ESIMS [M+H].sup.+=198.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 7.68 (s, 1H), 7.62
(br. s, 2H), 3.65 (t, 2H), 3.23 (s, 3H), 2.81 (t, 3H).
Acid-18:
3-Amino-6-chloro-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic
acid
a) 3-Amino-6-chloro-5-(1-ethoxy-vinyl)-pyrazine-2-carboxylic acid
methyl ester
[0562] A mixture of 3-amino-5,6-dichloro-pyrazine-2-carboxylic acid
methyl ester [1458-18-0] (600 mg, 2.62 mmol), lithium chloride (389
mg, 9.17 mmol), Pd(PPh.sub.3).sub.2Cl.sub.2 (184 mg, 0.262 mmol)
and tributyl-(1-ethoxy-vinyl)-stannane [97674-02-7] (1.6 ml, 4.50
mmol) in DMF (27 ml) under argon was heated at 80.degree. C. bath
temperature for 3 h and 50 min. Saturated aq. NH.sub.4Cl was added
and the mixture was extracted with MTBE (3.times.). The combined
organic layers were washed with brine, dried with Na.sub.2SO.sub.4,
filtered and concentrated under reduced pressure. The residue was
purified by chromatography on silica gel (cyclohexane to
cyclohexane/EtOAc 7:3) to provide the title compound as yellow
solid (433 mg).
[0563] HPLC: Rt.sub.H2=0.94 min; ESIMS [M+H].sup.+=258.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 7.59 (br. s, 2H), 4.64
(d, 1H), 4.58 (d, 1H), 3.91 (q, 3H), 3.86 (s, 3H), 1.31 (t,
2H).
b) 5-Acetyl-3-amino-6-chloro-pyrazine-2-carboxylic acid methyl
ester
[0564] A solution of
3-amino-6-chloro-5-(1-ethoxy-vinyl)-pyrazine-2-carboxylic acid
methyl ester (46 mg, 0.190 mmol) and para-toluenesulfonic acid
monohydrate (73.8 mg, 0.388 mmol) in THF (2.85 ml) was stirred at
rt for 1 h. Saturated aq. NaHCO.sub.3 was added and the mixture was
extracted twice with DCM. The combined organic layers were washed
with brine, dried with Na.sub.2SO.sub.4, filtered and concentrated
under reduced pressure to obtain a yellow solid (46 mg). This
material was used for the next step without further
purification.
[0565] HPLC: Rt.sub.H2=0.73 min; ESIMS [M+H].sup.+=230.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 7.70 (br. s, 2H), 3.83
(s, 3H), 2.58 (s, 3H).
c) 3-Amino-6-chloro-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic
acid methyl ester
[0566] To a cloudy yellow solution of
5-acetyl-3-amino-6-chloro-pyrazine-2-carboxylic acid methyl ester
(178 mg, 0.775 mmol) in dry DCM (7.75 ml) was added Deoxofluor 50%
in toluene (858 .mu.l, 2.326 mmol). The reaction was stirred at rt
over the weekend. More Deoxofluor 50% in toluene was added (six
times 858 .mu.L, 2.326 mmol) within 3 days to complete the
reaction. Saturated aq. NaHCO.sub.3 was added and the mixture was
extracted twice with EtOAc. The combined organic layers were washed
with aq. citric acid, dried with Na.sub.2SO.sub.4, filtered and
concentrated under reduced pressure. The residue was purified by
chromatography on silica gel (cyclohexane to cyclohexane/EtOAc 7:3)
to provide the title compound as yellow solid (136 mg).
[0567] HPLC: Rt.sub.H2=0.91 min; ESIMS [M+H].sup.+=252.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 7.75 (br. s, 2H), 3.88
(s, 3H), 2.02 (t, 3H).
d) 3-Amino-6-chloro-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic
acid
[0568] To a solution of
3-amino-6-chloro-5-(1,1-difluoro-ethyl)-pyrazine-2-carboxylic acid
methyl ester (136 mg, 0.541 mmol) in THF (5.40 ml) was added 1M
LiOH (595 .mu.l, 0.595 mmol) at 0.degree. C. The resulting brown
solution was warmed up to rt for 5 h. More 1M LiOH (95 .mu.l, 0.095
mmol) was added at 0.degree. C. and the reaction was stirred at rt
for 1 h. Then 1M HCl (632 .mu.l, 0.632 mmol) was added and then the
resulting mixture was evaporated to dryness. The resulting crude
material was directly used in the coupling step without further
purification.
[0569] HPLC: Rt.sub.H2=0.63 min; ESIMS [M+H].sup.+=238.1;
.sup.1H-NMR (400 MHz, DMSO-d.sub.6): .delta. 13.69 (br. s, 1H),
7.75 (br. s 2H), 2.02 (t, 3H).
Acid-19: 3-Chloro-5-(1,1-difluoro-ethyl)-pyridine-2-carboxylic
acid
a) 3-Chloro-5-(1-ethoxy-vinyl)-pyridine-2-carboxylic acid methyl
ester
[0570] To a solution of 5-bromo-3-chloro-pyridine-2-carboxylic acid
methyl ester [1458-18-0] (376 mg, 1.5 mmol) in dioxane (3.7 ml) was
added tributyl-(1-ethoxy-vinyl)-stannane [97674-02-7] (596 mg, 1.65
mmol), the solution was degassed and flushed with nitrogen
(3.times.), Pd(PPh.sub.3).sub.4 (87 mg, 0.075 mmol) was added,
after degassing and flushing with nitrogen the mixture was heated
to reflux for 4 h. The reaction mixture was diluted with EtOAc and
treated with 10% aq. KF, the precipitate was filtered off and the
layers were separated. The aq. Phase was extracted with EtOAc, the
combined organic layers were washed with sat. aq. NaCl, dried with
MgSO.sub.4, filtered and concentrated under reduced pressure. The
residue was purified by chromatography on silica gel
(cyclohexane/EtOAc 12:1 to 6/1) to provide the title compound as
yellow solid.
[0571] HPLC: Rt.sub.H7=2.822 min; ESIMS [M+H].sup.+=242.0/244.0;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 8.91-8.78 (m, 1H),
8.29-8.18 (m, 1H), 5.19 (d, 1H), 4.60 (d, 1H), 3.93 (q, 2H), 3.92
(s, 3H), 1.37 (t, 3H).
b) 5-Acetyl-3-chloro-pyridine-2-carboxylic acid methyl ester
[0572] To a solution of
3-chloro-5-(1-ethoxy-vinyl)-pyridine-2-carboxylic acid methyl ester
(359 mg, 1.485 mmol) in THF (3.6 ml) was added para-toluenesulfonic
acid monohydrate (565 mg, 2.97 mmol) and the mixture was stirred
for 1 h. The reaction mixture was diluted with TBME and sat. aq.
NaHCO.sub.3, the layers were separated and the aq. Phase was
extracted with TBME. The combined organic layers were washed with
sat. aq. NaHCO.sub.3 and sat. aq. NaCl, dried with MgSO.sub.4,
filtered and concentrated under reduced pressure. The residue was
purified by chromatography on silica gel (cyclohexane/EtOAc 9:1 to
6/1) to provide the title compound as yellow solid.
[0573] HPLC: Rt.sub.H8=2.604 min; ESIMS [M+H].sup.+=214.0/216.0;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 9.17-8.99 (m, 1H),
8.63-8.46 (m, 1H), 3.96 (s, 3H), 2.69 (s, 3H).
c) 3-Chloro-5-(1,1-difluoro-ethyl)-pyridine-2-carboxylic acid
methyl ester
[0574] To a solution of 5-acetyl-3-chloro-pyridine-2-carboxylic
acid methyl ester (278 mg, 1.30 mmol) in DCM (2.8 ml) was added
Deoxofluor.RTM. (50 w-% in toluene, 1.44 ml, 3.9 mmol) and the
reaction mixture was stirred protected from sunlight at rt for 6 h,
more Deoxofluor.RTM. (50 w-% in toluene, 1.44 ml, 3.9 mmol) was
added and the mixture was stirred over night. The reaction mixture
was poured on cold sat. aq. NaHCO.sub.3 (strong gas evolution),
TBME was added and the layers were separated. The aq. phase was
extracted with TBME, the combined TBME layers were washed with sat.
aq. NaHCO.sub.3, sat. aq. NaCl, dried with MgSO.sub.4, filtered and
evaporated. The residue was purified by chromatography on silica
gel (cyclohexane/EtOAc 95:5 to 93/7) to provide the title compound
as colorless oil.
[0575] HPLC: Rt.sub.H8=3.140 min; ESIMS [M+H].sup.+=236.0/238.0;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 8.84 (s, 1H), 8.40 (s,
1H), 3.95 (s, 3H), 2.07 (t, 3H).
d) 3-Chloro-5-(1,1-difluoro-ethyl)-pyridine-2-carboxylic acid
[0576] To a solution of
3-chloro-5-(1,1-difluoro-ethyl)-pyridine-2-carboxylic acid methyl
ester (272 mg, 1.154 mmol) in THF (6 ml) was added LiOH (30.4 mg,
1.27 mmol) in water (0.5 ml) and the mixture was stirred for 3.5 h.
To the mixture was added 6N HCl (0.212 ml, 1.27 mmol) and the
solvent was evaporated. The residue was taken up in toluene and
evaporated (2.times.) to provide the title compound as colorless
solid together with LiCl. This material was directly used in the
coupling step without further purification.
[0577] HPLC: Rt.sub.H5=2.743 min; ESIMS [M+H].sup.+=222.0/224.0;
.sup.1H-NMR (600 MHz, DMSO-d.sub.6): .delta. 8.76 (s, 1H), 8.29 (s,
1H), 3.37 (br. s, 1H), 2.06 (t, 3H).
* * * * *