U.S. patent application number 12/047425 was filed with the patent office on 2008-06-26 for spiroazabicyclic heterocyclic compounds.
Invention is credited to Robert Mack, John Macor, Eifion Phillips, Simon Semus.
Application Number | 20080153864 12/047425 |
Document ID | / |
Family ID | 26663041 |
Filed Date | 2008-06-26 |
United States Patent
Application |
20080153864 |
Kind Code |
A1 |
Phillips; Eifion ; et
al. |
June 26, 2008 |
Spiroazabicyclic Heterocyclic Compounds
Abstract
A compound of formula ##STR00001## wherein n, m, p, X, Y, W, A,
G and D are as defined in the specification, enantiomers thereof,
pharmaceutical compositions containing said compound,
pharmaceutically acceptable salts thereof, its use in therapy,
especially in the treatment of psychotic disorders and intellectual
impairment disorders.
Inventors: |
Phillips; Eifion;
(Rochester, NY) ; Mack; Robert; (Rochester,
NY) ; Macor; John; (Flemington, NJ) ; Semus;
Simon; (Bensalem, PA) |
Correspondence
Address: |
ASTRA ZENECA PHARMACEUTICALS LP;GLOBAL INTELLECTUAL PROPERTY
1800 CONCORD PIKE
WILMINGTON
DE
19850-5437
US
|
Family ID: |
26663041 |
Appl. No.: |
12/047425 |
Filed: |
March 13, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10801085 |
Mar 15, 2004 |
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12047425 |
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10396215 |
Mar 24, 2003 |
6706878 |
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10801085 |
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10093939 |
Mar 8, 2002 |
6703502 |
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10396215 |
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09594703 |
Jun 16, 2000 |
6369224 |
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10093939 |
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09171983 |
Oct 29, 1998 |
6110914 |
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PCT/SE98/01364 |
Jul 10, 1998 |
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09594703 |
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Current U.S.
Class: |
514/278 ;
540/466 |
Current CPC
Class: |
A61P 25/22 20180101;
A61P 25/14 20180101; A61P 1/04 20180101; A61P 1/00 20180101; A61P
25/28 20180101; A61P 25/16 20180101; A61P 25/00 20180101; A61P
25/18 20180101; A61P 25/24 20180101; C07D 491/22 20130101; A61P
25/34 20180101; A61P 43/00 20180101; A61P 25/04 20180101 |
Class at
Publication: |
514/278 ;
540/466 |
International
Class: |
A61K 31/439 20060101
A61K031/439; C07D 487/22 20060101 C07D487/22; A61P 25/28 20060101
A61P025/28; A61P 25/00 20060101 A61P025/00; A61P 25/16 20060101
A61P025/16; A61P 25/18 20060101 A61P025/18 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 18, 1997 |
SE |
9702746-0 |
Mar 24, 1998 |
SE |
9800977-2 |
Claims
1-32. (canceled)
33. Spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
or an enantiomer thereof.
34. A compound according to claim 33 in (R)-enantiomeric form.
35. A compound according to claim 34 crystallized as the
D-(-)-tartrate.
36. A pharmaceutical composition comprising a compound as defined
in claim 34.
37. A pharmaceutical composition according to claim 36 comprising
an inert pharmaceutically acceptable diluent or carrier.
38. A pharmaceutical composition comprising a compound as defined
in claim 35.
39. A pharmaceutical composition according to claim 38 comprising
an inert pharmaceutically acceptable diluent or carrier.
40. A method of treating human diseases or conditions in which
activation of the .alpha.7 nicotinic receptor is beneficial which
comprises administering a therapeutically effective amount of a
compound as defined in claim 34.
41. A method of treating psychotic disorders or intellectual
impairment disorders, which comprises administering a
therapeutically effective amount of a compound as defined in claim
34.
42. A method according to claim 41, wherein the disorder is
Alzheimer's disease, learning deficit, cognition deficit, attention
deficit, memory loss, or Attention Deficit Hyperactivity
Disorder.
43. A method according to claim 41, wherein the disorder is
Parkinson's disease, Huntington's disease, Tourette's syndrome, or
a neurodegenerative disorder in which there is loss of cholinergic
synapses.
44. A method according to claim 41, wherein the disorder is
anxiety, schizophrenia, mania or manic depression.
Description
TECHNICAL FIELD
[0001] This invention relates to novel spiroazabicyclic
heterocyclic amines or pharmaceutically acceptable salts thereof,
processes for preparing them, pharmaceutical compositions
containing them and their use in therapy. A further object is to
provide active compounds which are potent ligands for nicotinic
acetylcholine receptors (nAChR's).
BACKGROUND OF THE INVENTION
[0002] The use of compounds which bind nicotinic acetylcholine
receptors in the treatment of a range of disorders involving
reduced cholinergic function such as Alzheimer's disease, cognitive
or attention disorders, anxiety, depression, smoking cessation,
neuroprotection, schizophrenia, analgesia, Tourette's syndrome, and
Parkinson's disease has been discussed in McDonald et al. (1995)
"Nicotinic Acetylcholine Receptors: Molecular Biology, Chemistry
and Pharmacology", Chapter 5 in Annual Reports in Medicinal
Chemistry, vol. 30, pp. 41-50, Academic Press Inc., San Diego,
Calif.; and in Williams et al. (1994) "Neuronal Nicotinic
Acetylcholine Receptors," Drug News & Perspectives, vol. 7, pp.
205-223.
[0003] U.S. Pat. No. 5,468,875 discloses N-alkylcarbamic acid
1-azabicyclo[2.2.1]hept-3-yl esters which are centrally active
muscarinic agents useful in the treatment of Alzheimer's disease
and other disorders.
[0004] N-(2-alkoxyphenyl)carbamic acid
1-azabicyclo[2.2.2]octan-3-yl esters are disclosed in Pharmazie,
vol. 48, 465-466 (1993) along with their local anesthetic activity.
N-phenylcarbamic acid 1-azabicyclo[2.2.2]octan-3-yl esters
substituted at the ortho position on the phenyl ring are described
as local anaesthetics in Acta Pharm. Suecica, 7, 239-246
(1970).
[0005] Furopyridines useful in controlling synaptic transmission
are disclosed in WO 97/05139.
DISCLOSURE OF THE INVENTION
[0006] According to the invention it has been found that a compound
of formula I
##STR00002##
wherein n is 0 or 1; m is 0 or 1; p is 0 or 1;
Y is CH, N or NO
[0007] X is oxygen or sulfur; W is oxygen, H.sub.2 or F.sub.2;
A is N or C(R.sup.2);
G is N or C(R.sup.3);
D is N or C(R.sup.4);
[0008] with the proviso that no more than one of A, G, and D is
nitrogen but at least one of Y, A, G, and D is nitrogen or NO;
R.sup.1 is hydrogen or C.sub.1-C.sub.4 alkyl; R.sup.2, R.sup.3, and
R.sup.4 are independently hydrogen, halogen, C.sub.1-C.sub.4 alkyl,
C.sub.2-C.sub.4 alkenyl, C.sub.2-C.sub.4 alkynyl, aryl, heteroaryl,
OH, OC.sub.1-C.sub.4 alkyl, CO.sub.2R.sup.1, --CN, --NO.sub.2,
--NR.sup.5R.sup.6, --CF.sub.3, --OSO.sub.2CF.sub.3, or R.sup.2 and
R.sup.3, or R.sup.3 and R.sup.4, respectively, may together form
another six membered aromatic or heteroaromatic ring sharing A and
G, or G and D, respectively containing between zero and two
nitrogen atoms, and substituted with one to two of the following
substituents: independently hydrogen, halogen, C.sub.1-C.sub.4
alkyl, C.sub.2-C.sub.4 alkenyl, C.sub.2-C.sub.4 alkynyl, aryl,
heteroaryl, OH, OC.sub.1-C.sub.4 alkyl, CO.sub.2R.sup.1, --CN,
--NO.sub.2, --NR.sup.5R.sup.6, --CF.sub.3, OSO.sub.2CF.sub.3;
R.sup.5 and R.sup.6 are independently hydrogen, C.sub.1-C.sub.4
alkyl, C(O)R.sup.7, C(O)NHR.sup.8, C(O)OR.sup.9, SO.sub.2R.sup.10
or may together be (CH.sub.2).sub.jQ(CH.sub.2).sub.k where Q is O,
S, NR.sup.11, or a bond; j is 2 to 7; k is 0 to 2; R.sup.7,
R.sup.8, R.sup.9, R.sup.10, and R.sup.11 are independently
C.sub.1-C.sub.4 alkyl, aryl, or heteroaryl, or an enantiomer
thereof, and the pharmaceutically acceptable salts thereof is a
potent ligand for nicotinic acetylcholine receptors.
[0009] Unless otherwise indicated, the C.sub.1-C.sub.4 alkyl groups
referred to herein, e.g., methyl, ethyl, n-propyl, n-butyl,
i-propyl, i-butyl, t-butyl, s-butyl, may be straight-chained or
branched, and the C.sub.3-C.sub.4 alkyl groups may also be cyclic,
e.g., cyclopropyl, cyclobutyl.
[0010] Unless otherwise indicated, the C.sub.1-C.sub.6 alkyl groups
referred to herein, e.g., methyl, ethyl, n-propyl, n-butyl,
i-propyl, i-butyl, t-butyl, s-butyl, n-pentyl, i-pentyl, t-pentyl,
neo-pentyl, n-hexyl, or i-hexyl may be straight-chained or
branched, and the C.sub.3-C.sub.6 alkyl groups may also be cyclic,
e.g., cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl.
[0011] Unless otherwise indicated, the C.sub.1-C.sub.4 alkoxy
groups referred to herein, e.g., methoxy, ethoxy, n-propoxy,
i-propoxy, n-butoxy, i-butoxy, t-butoxy, s-butoxy, may be
straight-chained or branched.
[0012] Unless otherwise indicated, the C.sub.2-C.sub.4 alkenyl
groups referred to herein may contain one or two double bonds,
e.g., ethenyl, i-propenyl, n-butenyl, i-butenyl, allyl,
1,3-butadienyl.
[0013] Unless otherwise indicated, the C.sub.2-C.sub.4 alkynyl
groups referred to herein contain one triple bond, e.g., ethynyl,
propynyl, 1- or 2-butynyl.
[0014] Halogen referred to herein may be fluoride, chloride,
bromide, or iodide.
[0015] Unless otherwise indicated, aryl refers to a phenyl ring
optionally substituted with one to three of the following
substituents: hydrogen, halogen, C.sub.1-C.sub.4 alkyl,
C.sub.2-C.sub.4 alkenyl, C.sub.2-C.sub.4 alkynyl, OH,
OC.sub.1-C.sub.4 alkyl, CO.sub.2R.sup.1, --CN, --NO.sub.2,
--NR.sup.5R.sup.6, --CF.sub.3;
[0016] Unless otherwise indicated, heteroaryl refers to a five- or
six-membered aromatic ring containing one or two nitrogen atoms,
such as pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, pyrrolyl,
imidazolyl or pyrazolyl, with the carbon atoms of that ring
optionally substituted with one to three of the following
substituents: hydrogen, halogen, C.sub.1-C.sub.4 alkyl,
C.sub.2-C.sub.4 alkenyl, C.sub.2-C.sub.4 alkynyl, OH,
OC.sub.1-C.sub.4 alkyl, CO.sub.2R.sup.1, --CN, --NO.sub.2,
--NR.sup.5R.sup.6, --CF.sub.3; R.sup.5 and R.sup.6 may together be
(CH.sub.2).sub.jQ(CH.sub.2).sub.k where Q is O, S, NR.sup.11, or a
bond, and where j is 2 to 7, preferably 2 to 3, and k is 0 to 2, so
as to form a 3-7 membered ring, preferably a 5- or 6-membered ring,
for example pyrrolidinyl, imidazolidinyl piperazinyl, piperidyl,
morpholinyl, or thiomorpholinyl.
[0017] R.sup.2 and R.sup.3 may together form another six membered
aromatic or heteroaromatic ring sharing A and G containing between
zero and two nitrogen atoms refers to groups such as quinoline,
1,5-, 1,6-, 1,7-, or 1,8-diazanaphthalene.
[0018] R.sup.3 and R.sup.4 may together form another six membered
aromatic or heteroaromatic ring sharing G and D containing between
zero and two nitrogen atoms refers to groups such as isoquinoline,
2,5-, 2,6-, 2,7-, or 2,8-diazanaphthalene.
[0019] Preferred compounds of the invention are compounds of
formula I wherein m is 1; n is 0; p is 0; X is oxygen; W is
H.sub.2; A is C(R.sup.2); G is C(R.sup.3); D is C(R.sup.4).
[0020] Preferred compounds of the invention include the following:
[0021]
spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine];
[0022]
5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine];
[0023]
5'-phenylspiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyr-
idine]; [0024]
5'-nitrospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine];
[0025]
1'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]iso-
quinoline]; [0026]
5'-(phenylcarboxamido)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-
-b]pyridine]; [0027]
5'-(phenylaminocarbonylamino)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-f-
uro[2,3-b]pyridine]; [0028]
5'-(phenylsulfonylamido)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2-
,3-b]pyridine]; [0029]
5'-aminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine];
[0030]
5'-N-methylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,-
3-b]pyridine]; [0031]
5'-N,N-dimethylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b-
]pyridine]; [0032]
5'-N,N-diethylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]-
pyridine]; [0033]
5'-N-ethylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyri-
dine]; [0034]
5'-N-benzylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyr-
idine]; [0035]
5'-N-formamidospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyrid-
ine]; [0036]
5'-N-acetamidospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyrid-
ine]; [0037]
spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]isoquinoline];
[0038]
spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]quinoline];
[0039]
5'-ethenylspiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]py-
ridine]; [0040]
5'-(E)-(phenylethenyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-
-b]pyridine]; [0041]
5'-(4-morpholino)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]py-
ridine]; [0042]
5'-(1-azetidinyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]py-
ridine]; [0043]
5'-(E)-(2-(4-pyridyl)ethenyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-f-
uro[2,3-b]pyridine]; [0044]
5'-(E)-(2-(2-pyridyl)ethenyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-f-
uro[2,3-b]pyridine]; [0045]
5'-(2-trimethylsilylethynyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-fu-
ro[2,3-b]pyridine]; [0046]
5'-ethynylspiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine]-
; [0047]
5'-(2-furyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b-
]pyridine]; [0048]
5'-(3-pyridyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyrid-
ine]; [0049]
5'-methylspiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine];
[0050]
spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine-5'c-
arbonitrile]; [0051]
spiro[1'-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine-5'carboxa-
mide]; [0052]
5'-N'-(3-chlorophenyl)aminocarbonylminospiro[1-azabicyclo[2.2.2]octane-3,-
2'-(3'H)-furo[2,3-b]pyridine]; [0053]
5'-N'-(2-nitrophenyl)aminocarbonylaminospiro[1-azabicyclo[2.2.2]octane-3,-
2'-(3'H)-furo[2,3-b]pyridine]; [0054]
4'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine];
[0055]
4'-methoxyspiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]py-
ridine]; [0056]
4'-phenylthiospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridi-
ne]; [0057]
4'-(N-2-aminoethyl)aminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2-
,3-b]pyridine]; [0058]
4'-phenylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyrid-
ine]; [0059]
4'-methylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyrid-
ine]; [0060]
4'-(4-N-methylpiperazin-1-yl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-f-
uro[2,3-b]pyridine]; [0061]
4'-chloro-spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[3,2-c]pyridine]-
; [0062]
spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[3,2-c]pyridine];
[0063]
spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-7'-o-
xide]; [0064]
spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-6'-carbonit-
rile]; [0065]
6'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine];
[0066]
6'-fluorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyri-
dine]; and the enantiomers, and pharmaceutically acceptable salts
thereof.
[0067] Particularly preferred compounds of the invention are
compounds of formula I wherein m is 1; n is 0; p is 0; X=oxygen; W
is H.sub.2; A=CH, D=CH, and G=C(R3), including the following
compounds: [0068]
spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine];
[0069]
spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-7'-oxide];
[0070]
5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyri-
dine]; [0071]
5'-phenylspiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine];
[0072]
5'-nitrospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyri-
dine]; [0073]
5'-(phenylcarboxamido)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-
-b]pyridine]; [0074]
5'-(phenylaminocarbonylamino)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-f-
uro[2,3-b]pyridine]; [0075]
5'-(phenylsulfonylamido)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2-
,3-b]pyridine]; [0076]
5'-aminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine];
[0077]
5'-N-methylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,-
3-b]pyridine]; [0078]
5'-N,N-dimethylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b-
]pyridine]; [0079]
5'-N,N-diethylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]-
pyridine]; [0080]
5'-N-ethylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyri-
dine]; [0081]
5'-N-benzylaminospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyr-
idine]; [0082]
5'-N-formamidospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyrid-
ine]; [0083]
5'-N-acetamidospiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyrid-
ine]; [0084]
5'-ethenylspiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine]-
; [0085]
5'-(E)-(phenylethenyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)--
furo[2,3-b]pyridine]; [0086]
5'-(4-morpholino)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]py-
ridine]; [0087]
5'-(1-azetidinyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]py-
ridine]; [0088]
5'-(E)-(2-(4-pyridyl)ethenyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-f-
uro[2,3-b]pyridine]; [0089]
5'-(E)-(2-(2-pyridyl)ethenyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-f-
uro[2,3-b]pyridine]; [0090]
5'-(2-trimethylsilylethynyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-fu-
ro[2,3-b]pyridine]; [0091]
5'-ethynylspiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine]-
; [0092]
5'-(2-furyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b-
]pyridine]; [0093]
5'-(3-pyridyl)spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyrid-
ine]; [0094]
5'-methylspiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine];
[0095]
spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine-5'c-
arbonitrile]; [0096]
spiro[1-azabicyclo[2.2.2]octane-3,2'-(3'H)-furo[2,3-b]pyridine-5'carboxam-
ide]; [0097]
5'-N'-(3-chlorophenyl)aminocarbonylminospiro[1-azabicyclo[2.2.2]octane-3,-
2'-(3'H)-furo[2,3-b]pyridine]; [0098]
5'-N'-(2-nitrophenyl)aminocarbonylaminospiro[1-azabicyclo[2.2.2]octane-3,-
2'-(3'H)-furo[2,3-b]pyridine];
Methods of Preparation
[0099] In the reaction schemes and text that follow, A, G, D, X, W,
Y, Z, m, n, and p, unless otherwise indicated, are as defined above
for formula I.
(A) Compounds Wherein p is 0 and Y is N
[0100] The compounds of formula I, wherein p is 0 and Y is N, may
be prepared according to the methods outlined in Scheme I.
##STR00003##
[0101] Compounds of formula I where W=H.sub.2 and p is 0 may be
prepared from the deprotection of a compound of formula IIA using
acid in a suitable solvent. Suitable acids include mineral, organic
and Lewis acids, for example, hydrochloric and hydrobromic acid,
sulfuric acid, triflic acid, methanesulfonic acid, and boron
trifluoride etherate. The preferred acid is hydrobromic acid.
Suitable solvents include acetone, butanone, ethanone, and
pinacolone. The preferred solvent is acetone. The reaction is
usually conducted at a temperature from about -10.degree. C. to
about 100.degree. C., preferably about 0.degree. C. to about
60.degree. C. Alternatively the deprotection may be conducted by
heating the borane complex in alcoholic solvents. A preferred
method is by refluxing a ethanolic solution of the complex.
[0102] Compounds of formula I where W=O (oxygen) and p is 0 may be
prepared by the oxidation of compounds of formula IIA, for example
using selenium dioxide, or by reaction first with
N-bromosuccinimide then with sodium bicarbonate and
methylsulfoxide, followed by removal of the borane group as
described above.
[0103] Compounds of formula I where W=F.sub.2 and p is 0 may be
prepared from compounds of formula I where W=O by reaction with a
fluorinating agent, for example diethylaminosulfur trifluoride.
[0104] Compounds of formula IIA may be prepared from the
cyclization of a compound of formula III wherein L is fluoro,
chloro, bromo, iodo, --OCH.sub.3, --SPh, --SCH.sub.3, --SO.sub.2Ph,
or --SO.sub.2CH.sub.3 in the presence of a base in an inert
solvent. Suitable bases include sodium hydride, sodium amide,
potassium hydride, potassium t-amylate, potassium t-butoxide, and
potassium bis(trimethylsilyl)amide. The preferred base is sodium
hydride. Suitable inert solvents include N,N-dimethylformamide,
N-methylpyrrolidin-2-one, ethers such as diethyl ether,
tetrahydrofuran, and 1,4-dioxane, and dimethylsulfoxide. The
preferred inert solvent is N,N-dimethylformamide. The reaction is
usually conducted at a temperature from about 10.degree. C. to
about 100.degree. C., preferably about 20.degree. C. to about
66.degree. C.
[0105] Compounds of formula III wherein L is fluoro, chloro, bromo,
iodo, --OCH.sub.3, --SPh, --SCH.sub.3, --SO.sub.2Ph, or
--SO.sub.2CH.sub.3 may be prepared by the reaction of a compound of
formula IV with a compound of formula V wherein L is defined as
above in an inert solvent. Suitable inert solvents include diethyl
ether, tetrahydrofuran and 1,4-dioxane. The preferred inert solvent
is tetrahydrofuran. The reaction is usually conducted at a
temperature from about -100.degree. C. to about 0.degree. C.,
preferably about -78.degree. C. to about -25.degree. C.
[0106] Compounds of formula V wherein L is defined as above may be
prepared from a compound of formula VIII wherein L is defined as
above using a lithium base and a proton transfer agent in an inert
solvent. Suitable lithium bases include lithium diisopropylamide,
n-butyllithium, sec-butyllithium, tert-butyllithium, and
phenyllithium. The preferred lithium base is phenyllithium.
Suitable proton transfer agents include hindered secondary amines
such as diisopropylamine and 2,2,6,6-tetramethylpiperidine. The
preferred proton transfer agent is diisopropylamine. Suitable inert
solvents include diethyl ether, tetrahydrofuran and 1,4-dioxane.
The preferred inert solvent is tetrahydrofuran. The reaction is
usually conducted at a temperature from about -100.degree. C. to
about 0.degree. C., preferably about -78.degree. C. to about
-25.degree. C. Compounds of formula V are usually taken directly
into the reaction with compounds of formula IV without
purification.
[0107] Compounds of formula IV may be prepared from the reaction of
a compound of formula VI with borane (BH.sub.3 or B.sub.2H.sub.6)
in an inert solvent. Borane in tetrahydrofuran is preferred.
Suitable inert solvents include diethyl ether, tetrahydrofuran and
1,4-dioxane. The preferred inert solvent is tetrahydrofuran. The
reaction is usually conducted at a temperature from about
-10.degree. C. to about 66.degree. C., preferably about 0.degree.
C. to about 20.degree. C.
[0108] Compounds of formula VIII are known, e.g., either
commercially available or may be prepared by methods known to one
skilled in the art (see e.g, The Chemistry of Heterocyclic
Compounds, Pyridine and Its Derivatives, Part 1, E. Klingsberg,
Ed., Interscience Publishers, Inc, NY, 1960).
[0109] Compounds of formula VI may be prepared from compounds of
formula VII by methods known to one skilled in the art. For
example, compounds of formula VI wherein X represents oxygen may be
prepared from the corresponding compound of formula VII wherein X
represents the oxygen of a ketone using one of the reagents well
known in the art for preparation of oxiranes from ketones (see e.g.
the reactions referenced in J. March, "Advanced Organic Chemistry"
(1985) 3rd Edition, page 1161). Compounds of formula VI wherein X
represents sulfur may be prepared from the corresponding compound
of formula VII wherein X represents either oxygen or sulfur using
one of the methods well known in the art for preparation of
episulfides from ketones or thioketones (see, e.g. the reactions
referenced in J. March, "Advanced Organic Chemistry" (1985) 3rd
Edition, pages 866-867).
[0110] Compounds of formula VII are known, e.g., either
commercially available or may be prepared by methods known to one
skilled in the art (see, e.g, The Chemistry of Heterocyclic
Compounds, Heterocyclic Systems with Bridgehead Nitrogen Atoms,
Part 2, W. L. Mosby, Ed., Interscience Publishers, Inc, NY,
1961).
(B) Compounds Wherein p is 1 and Y is N
[0111] The compounds of formula I (p=1) may be prepared according
to the methods described in Scheme II or Scheme III, below.
##STR00004##
##STR00005##
[0112] Compounds of formula I where W is H.sub.2 and p is 1 may be
prepared from the deprotection of a compound of formula IX using
acid in a suitable solvent. Suitable acids include mineral, organic
and Lewis acids, for example, hydrochloric and hydrobromic acid,
sulfuric acid, triflic acid, methanesulfonic acid and
borontrifluoride etherate. The preferred acid is hydrobromic acid.
Suitable solvents include acetone, butanone, ethanone, and
pinacolone. The preferred solvent is acetone. The reaction is
usually conducted at a temperature from about -10.degree. C. to
about 100.degree. C., preferably about 0.degree. C. to about
60.degree. C. Alternatively the deprotection may be conducted by
heating the borane complex in alcoholic solvents. A preferred
method is by refluxing a ethanolic solution of the complex.
[0113] Compounds of formula I where W=O and p is 1 may be prepared
by the oxidation of compounds of formula I, where W is H.sub.2 and
p is 1, using selenium dioxide, or by reaction first with
N-bromosuccinimide then with sodium bicarbonate and
methylsulfoxide, followed by removal of the borane group as
described above.
[0114] Compounds of formula I, where W=F.sub.2 and p is 1, may be
prepared from compounds of formula I, where W=O and p is 1, by
reaction with diethylaminosulfur trifluoride.
[0115] Compounds of formula IX may be prepared from the cyclization
of a compound of formula X wherein L is fluoro, chloro, bromo,
iodo, --OCH.sub.3, --SPh, --SCH.sub.3, --SO.sub.2Ph, or
--SO.sub.2CH.sub.3 in the presence of a base in an inert solvent.
Suitable bases include sodium hydride, sodium amide, potassium
hydride, potassium t-amylate, potassium t-butoxide, and potassium
bis(trimethylsilyl)amide. The preferred base is sodium hydride.
Suitable inert solvents include N,N-dimethylformamide,
N-methylpyrrolidin-2-one, ethers such as diethyl ether,
tetrahydrofuran, and 1,4-dioxane, and dimethylsulfoxide. The
preferred inert solvent is N,N-dimethylformamide. The reaction is
usually conducted at a temperature from about -10.degree. C. to
about 100.degree. C., preferably about 20.degree. C. to about
66.degree. C.
[0116] Compounds of formula X wherein L is fluoro, chloro, bromo,
iodo, --OCH.sub.3, --SPh, --SCH.sub.3, --SO.sub.2CH.sub.3 may be
prepared by the reaction of a compound of formula XI with a
compound of formula V wherein L is defined as above in an inert
solvent. Suitable inert solvents include diethyl ether,
tetrahydrofuran and 1,4-dioxane. The preferred inert solvent is
tetrahydrofuran. The reaction is usually conducted at a temperature
from about -10.degree. C. to about 0.degree. C., preferably about
-78.degree. C. to about -25.degree. C.
[0117] Compounds XI, wherein P is --SO.sub.2Ph,
--SO.sub.2PhCH.sub.3-4, --SO.sub.2CH.sub.3 or --SO.sub.2CF.sub.3
may be prepared from compounds XII by reaction with a reagent such
as toluenesulfonyl chloride, methanesulfonyl chloride, or
trifluoromethanesulfonyl chloride in the presence of an amine base
such as triethylamine, dimethylaminopyridine, or
diazabicyclo[4.3.0]nonane in an inert solvent. Suitable inert
solvents may be dichloromethane, chloroform, tetrahydrofuran,
diethyl ether, or dioxane. The preferred inert solvent is
dichloromethane. The reaction is usually conducted at a temperature
from about -10.degree. C. to about 66.degree. C., preferably about
0.degree. C. to about 20.degree. C.
[0118] Compounds XII may be prepared from compounds of formula XIII
by reduction with reagents such as lithium aluminum hydride, sodium
bis(2-methoxyethoxy)aluminum hydride, sodium or lithium
triethylboride, lithium tri-sec-butylborohydride, potassium
tri-sec-butylborohydride, sodium tri-sec-butylborohydride or
lithium borohydride. The preferred reagent is lithium borohydride.
Suitable inert solvents include diethyl ether, tetrahydrofuran and
1,4-dioxane. The preferred inert solvent is tetrahydrofuran. The
reaction is usually conducted at a temperature from about
-78.degree. C. to about 66.degree. C., preferably about -10.degree.
C. to about 20.degree. C.
[0119] Compounds of formula XIII, wherein R is C.sub.1-C.sub.6
alkyl, --CH.sub.2--Ar, or Ar, where Ar is phenyl optionally
substituted with one to three of the following substitutents:
halogen, C.sub.1-C.sub.4 alkyl, or C.sub.1-C.sub.4 alkoxy, may be
prepared from the reaction of a compound of formula XIV with borane
(BH.sub.3 or B.sub.2H.sub.6) in an inert solvent. Borane in
tetrahydrofuran is preferred. Suitable inert solvents include
diethyl ether, tetrahydrofuran and 1,4-dioxane. The preferred inert
solvent is tetrahydrofuran. The reaction is usually conducted at a
temperature from about -10.degree. C. to about 66.degree. C.,
preferably about 0.degree. C. to about 20.degree. C.
[0120] Compounds of formula XIV are known, e.g., either
commercially available or may be prepared from compounds of formula
VII by methods known to one skilled in the art for the preparation
of .beta.-hydroxy esters from the reaction of esters and ketones
(see, e.g. the reactions referenced in J. March, "Advanced Organic
Chemistry" (1985) 3rd Edition, page 439).
[0121] Compounds of formula I where W is H.sub.2 and p is 1 may be
prepared from the cyclization of a compound of formula XVIII
wherein L is fluoro, chloro, bromo, iodo, --OCH.sub.3, --SPh,
--SCH.sub.3, --SO.sub.2Ph, or --SO.sub.2CH.sub.3 in the presence of
a base in an inert solvent. Suitable bases include sodium hydride,
sodium amide, potassium hydride, potassium t-amylate, potassium
t-butoxide, and potassium bis(trimethylsilyl)amide. The preferred
base is sodium hydride. Suitable inert solvents include
N,N-dimethylformamide, N-methylpyrrolidin-2-one, ethers such as
diethyl ether, tetrahydrofuran, and 1,4-dioxane, and
dimethylsulfoxide. The preferred inert solvent is
N,N-dimethylformamide. The reaction is usually conducted at a
temperature from about -10.degree. C. to about 100.degree. C.,
preferably about 20.degree. C. to about 66.degree. C.
[0122] Compounds of formula XVIII wherein L is defined as above may
be prepared by catalytic hydrogenation of a compound of formula
XVII using catalysts such as palladium on carbon, palladium
hydroxide on carbon, palladium oxide, platinum on carbon, platinum
oxide, Raney nickel, or rhenium on carbon in an inert solvent.
Suitable inert solvents include methanol, ethanol, aqueous methanol
or ethanol and ethyl acetate. The preferred solvent is ethanol. The
reaction is usually conducted at a temperature from about 0.degree.
C. to about 100.degree. C., preferably about 20.degree. C. to about
50.degree. C.
[0123] Compounds of formula XVII wherein L is defined as above may
be prepared by reaction of a compound of formula XV with a compound
of formula XVI using a palladium catalyst, together with a suitable
ligand, base, and solvent. Suitable palladium catalysts include
palladium acetate. Suitable ligands include phosphine ligands, such
as triphenylphosphine or tri-o-tolylphosphine. Suitable bases
include amines and inorganic bases, such as triethylamine,
diisopropylethylamine, sodium carbonate or tetrabutylammonium
acetate. Suitable solvents include dimethylformamide or
acetonitrile. The reaction is usually conducted at a temperature
from about 0.degree. C. to about 140.degree. C., preferably about
20.degree. C. to about 85.degree. C.
[0124] Compounds of formula XVI, where L is defined as above and
R.sup.2 is chloro, bromo, iodo, fluoro, trifluoromethylsulfonyl,
toluenesulfonyl or methylsulfonyl may be prepared by literature
methods from commercially available materials.
[0125] Compounds of formula XV may be prepared from compounds of
formula VII by methods known to one skilled in the art for the
preparation of allyl alcohols from ketones using vinylmetal salts
such as vinylmagnesium bromide.
(C) Compounds Wherein p is 0 or 1
[0126] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is halogen may be prepared from compounds of formula I wherein the
corresponding substituent is hydrogen by reaction with a suitable
halogenating agent, for example bromine in acetic acid. The
transformation may require the addition of an acidic catalyst, such
as the corresponding iron trihalide.
[0127] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is C.sub.1-C.sub.4 alkyl, C.sub.2-C.sub.4 alkenyl, C.sub.2-C.sub.4
alkynyl, aryl, heteroaryl may be prepared from compounds of formula
I wherein the corresponding substituent is halogen or
OSO.sub.2CF.sub.3 by reaction with an appropriate alkyl, alkenyl,
alkynyl, aryl or heteroaryl stannane reagent, in the presence of a
suitable organometallic catalyst, for example
tetrakis(triphenylphosphine)palladium (0), in a suitable solvent,
for example 1,2-dimethoxyethane.
[0128] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is aryl, heteroaryl may be prepared from compounds of formula I
wherein the corresponding substituent is halogen or
OSO.sub.2CF.sub.3 by reaction with an aryl or heteroaryl boronic
acid, in the presence of a suitable organometallic catalyst, for
example tetrakis(triphenylphosphine)palladium (0), in a suitable
solvent, for example 1,2-dimethoxyethane.
[0129] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is NO.sub.2 may be prepared from compounds of formula I wherein the
corresponding substituent is hydrogen by nitration using a suitable
nitrating agent, for example nitric acid in concentrated sulfuric
acid.
[0130] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is NH.sub.2 may be prepared from compounds of formula I wherein the
corresponding substituent is NO.sub.2 by reduction using a suitable
procedure, for example hydrogenation. Hydrogenation may be
performed by the reaction of a compound, dissolved in a suitable
solvent, with gaseous hydrogen in the presence of a suitable
catalyst. Suitable solvents include methanol, ethanol, and acetic
acid. Suitable catalysts include palladium, for example as 10%
palladium on carbon.
[0131] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is NR.sup.5R.sup.6 wherein R.sup.6 is alkyl may be prepared from
compounds of formula I wherein the corresponding substituent is
NHR.sup.5 by a suitable alkylation procedure. Also, compounds of
formula I wherein R.sup.2, R.sup.3, or R.sup.4 is NR.sup.5R.sup.6
wherein R.sup.5 and R.sup.6 are identical alkyl groups or R.sup.5
and R.sup.6 together are (CH.sub.2).sub.jQ(CH.sub.2).sub.k may be
prepared from compounds of formula I wherein the corresponding
substituent is NH.sub.2 by a suitable alkylation procedure.
Suitable alkylation procedures may include treatment with a
suitable alkyl halide or sulfonate ester and base, for example
sodium hydride, in a suitable solvent, for example DMF, or
treatment with a suitable aldehyde or ketone in the presence of an
acidic catalyst, for example zinc chloride, a reducing agent, for
example sodium cyanoborohydride, and solvent, for example
ethanol.
[0132] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is OSO.sub.2CF.sub.3 may be prepared from compounds of formula I
wherein the corresponding substituent is OH by reaction with
trifluoromethanesulfonic anhydride in the presence of a suitable
base, for example 2,6-di-t-butylpyridine, in a suitable solvent,
for example dichloromethane.
[0133] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is NR.sup.5R.sup.6 may also be prepared from compounds of formula I
wherein the corresponding substituent is halide or
OSO.sub.2CF.sub.3 by substitution with the appropriate amine
NHR.sup.5R.sup.6. Suitable procedures include nucleophilic
displacement, involving treatment with the amine, in excess or in
the presence of an added base, and a suitable solvent, for example
DMSO, or organometallic complex catalysed substitution, involving
treatment with the amine in the presence of a suitable
organometallic complex, for example complexes of palladium with
chelating phosphine ligands, as described in J. Org. Chem., 1996,
vol. 61, pp. 7240.
[0134] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is NR.sup.5C(O)R.sup.7 may be prepared from compounds of formula I
wherein the corresponding substituent is NH.sub.2 by a suitable
acylation procedure. Suitable acylation procedures include
treatment with a carboxylic acid chloride R.sup.6C(O)Cl in the
presence of an optional nucleophilic catalyst, such as
4-(N,N-dimethylamino)pyridine, a base, for example pyridine or
triethylamine, and a suitable solvent, for example tetrahydrofuran,
or, alternatively, treatment with a carboxylic acid R.sub.6C(O)OH
with a coupling agent, for example 1,3-dicyclohexylcarbodiimide, in
a suitable solvent, for example tetrahydrofuran.
[0135] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is NR.sup.5C(O)NHR.sup.8 may be prepared from compounds of formula
I wherein the corresponding substituent is NHR.sup.5 by treatment
with the appropriate isocyanate R.sup.8NCO in a suitable solvent,
for example tetrahydrofuran.
[0136] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is NR.sup.5C(O)OR.sup.9 may be prepared from compounds of formula I
wherein the corresponding substituent is NHR.sup.5 by treatment
with an appropriate oxychloride or carbonate in the presence of an
optional nucleophilic catalyst, such as
4-(N,N-dimethylamino)pyridine, a base, for example pyridine or
triethylamine, and a suitable solvent, for example
tetrahydrofuran.
[0137] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is NR.sup.5SO.sub.2R.sup.10 may be prepared from compounds of
formula I wherein the corresponding substituent is NHR.sup.5 by
treatment with an appropriate sulfonyl chloride in a suitable
solvent, such as pyridine.
[0138] Compounds of formula I wherein R.sup.2, R.sup.3, or R.sup.4
is CN may be prepared from compounds of formula I wherein the
corresponding substituent is halide or OSO.sub.2CF.sub.3 by
reaction with a cyanide salt, in a suitable solvent, with the
addition of a suitable catalyst possibly also being required.
Suitable cyanide salts include copper (I) cyanide, sodium cyanide,
sodium dicyanocuprate, or potassium cyanide, and suitable solvents
include N,N-dimethylformamide, dimethylsulfoxide, or pyridine.
Catalysts which may facilitate the transformation include copper
(I) oxide, tetrakis(triphenylphosphine)palladium (0), or nickel (0)
complexes generated in situ from
dibromobis(triphenylphosphine)nickel(ii), zinc and
triphenylphosphine.
[0139] Compounds of formula I wherein R.sup.2, R.sup.3 or R.sup.4
is OH, OC.sub.1-C.sub.4 alkyl may be prepared either from an
appropriately substituted 2-chloropyridine or via chemical
transformation from another substituent e.g; the OH derivative from
the NH.sub.2 via the diazo intermediate.
[0140] Where necessary, hydroxy, amino, or other reactive groups
may be protected using a protecting group as described in the
standard text "Protecting Groups in Organic Synthesis", 2.sup.nd
Edition (1991) by Greene and Wuts.
[0141] Compounds of Formula I may be prepared from other compounds
of Formula I by using general methods known to one skilled in the
art for interconversion of functional groups (see, e.g. the
reactions referenced in J. March, "Advanced Organic Chemistry"
(1985) 3rd Edition).
[0142] Also, several of the substituted compounds of Formula I may
be prepared by using an appropriately substituted compound of
Formula VIII, viz., 2-chloro-5-trifluoromethylpyridine would yield
the R.sup.3 is CF.sub.3.
[0143] The above-described reactions, unless otherwise noted, are
usually conducted at a pressure of about one to about three
atmospheres, preferably at ambient pressure (about one atmosphere).
Unless otherwise stated, the above-described reactions are
conducted under an inert atmosphere, preferably under a nitrogen
atmosphere.
[0144] The compounds of the invention and intermediates may be
isolated from their reaction mixtures by standard techniques.
[0145] Acid addition salts of the compounds of formula I which may
be mentioned include salts of mineral acids, for example the
hydrochloride and hydrobromide salts; and salts formed with organic
acids such as formate, acetate, maleate, benzoate, tartrate, and
fumarate salts.
[0146] Acid addition salts of compounds of formula I may be formed
by reacting the free base or a salt, enantiomer or protected
derivative thereof, with one or more equivalents of the appropriate
acid. The reaction may be carried out in a solvent or medium in
which the salt is insoluble or in a solvent in which the salt is
soluble, e.g., water, dioxane, ethanol, tetrahydrofuran or diethyl
ether, or a mixture of solvents, which may be removed in vacuum or
by freeze drying. The reaction may be a metathetical process or it
may be carried out on an ion exchange resin.
[0147] The compounds of formula I exist in tautomeric or
enantiomeric forms, all of which are included within the scope of
the invention. The various optical isomers may be isolated by
separation of a racemic mixture of the compounds using conventional
techniques, e.g. fractional crystallization, or chiral HPLC.
Alternatively the individual enantiomers may be made by reaction of
the appropriate optically active starting materials under reaction
conditions that will not cause racemization.
(D) Compounds Wherein Y is NO
[0148] Compounds of formula I, wherein Y is NO, X is oxygen, A is
C(R.sup.2), G is C(R.sup.3) and D is C(R.sup.4), may be prepared
from compounds of formula XIX, wherein X is oxygen, A is
C(R.sup.2), G is C(R.sup.3) and D is C(R.sup.4), by reduction with
a suitable reducing agent under suitable conditions, for example
sulfur dioxide in ethanol at ambient temperature.
##STR00006##
[0149] Compounds of formula XIX may be prepared from compounds of
formula I wherein Y is N, X is oxygen, A is C(R.sup.2), G is
C(R.sup.3) and D is C(R.sup.4), by oxidation with a suitable
oxidising agent under suitable conditions, for example aqueous
hydrogen peroxide in acetic acid at reflux temperature.
[0150] Compounds of the formula I wherein Y is N, X is oxygen, A is
C(R.sup.2), G is C(R.sup.3) and D is C(R.sup.4), may be prepared in
analogy with sections (A), (B) and (C), above.
[0151] Compounds of formula I, in which Y is N and A is C(R.sup.2),
wherein R.sup.2 is hydroxyl, may be prepared from compounds of
formula I in which Y is NO by rearrangement using a carboxylic
anhydride in a suitable solvent, for example trifluoroacetic
anhydride in DMF;
[0152] Compounds of formula I in which Y is N and A is C(R.sup.2),
wherein R.sup.2 is halogen, may be prepared from compounds of
formula I in which Y is NO and A is C(R.sup.2), wherein R.sup.2 is
hydrogen, by reaction with a phosphorus halide or oxyhalide, either
neat or with a suitable co-solvent, for example neat phosphorus
oxychloride.
[0153] Compounds of formula I in which Y is N and A is C(R.sup.2),
wherein R.sup.2 is CN, may be prepared from compounds of formula I
in which Y is NO and A is C(R.sup.2), wherein R.sup.2 is hydrogen,
by reaction with a suitable cyanide source such as trimethylsilyl
cyanide in the presence of a suitable base, for example
triethylamine, in a suitable solvent, for example acetonitrile.
Intermediates
[0154] A further aspect of the invention relates to new
intermediates. Special interest among these new intermediates are
the borane containing compounds, especially the compound of formula
II in Scheme I and the compound of formula XIII in Scheme II. These
intermediates are useful in the synthesis of compounds of formula
I, but their use is not limited to the synthesis of said
compounds;
[0155] Thus, compounds of the formula II
##STR00007##
wherein n is 0 or 1; m is 0 or 1; p is 0 or 1; X is oxygen or
sulfur; W is oxygen, H.sub.2 or F.sub.2;
A is N or C(R.sup.2);
G is N or C(R.sup.3);
D is N or C(R.sup.4);
[0156] with the proviso that no more than one of A, G, and D is
nitrogen; R.sup.1 is hydrogen or C.sub.1-C.sub.4 alkyl; R.sup.2,
R.sup.3, and R.sup.4 are independently hydrogen, halogen,
C.sub.1-C.sub.4 alkyl, C.sub.2-C.sub.4 alkenyl, C.sub.2-C.sub.4
alkynyl, aryl, heteroaryl, OH, OC.sub.1-C.sub.4 alkyl,
CO.sub.2R.sup.1, --CN, --NO.sub.2, --NR.sup.5R.sup.6, --CF.sub.3,
--OSO.sub.2CF.sub.3 or R.sup.2 and R.sup.3, or R.sup.3 or R.sup.4,
respectively, may together form another six membered aromatic or
heteroaromatic ring sharing A and G, or G and D, respectively,
containing between zero and two nitrogen atoms, and substituted
with one to two of the following substituents: independently
hydrogen, halogen, C.sub.1-C.sub.4 alkyl, C.sub.2-C.sub.4 alkenyl,
C.sub.2-C.sub.4 alkynyl, aryl, heteroaryl, OH, OC.sub.1-C.sub.4
alkyl, CO.sub.2R.sub.1, --CN, --NO.sub.2, --NR.sup.5R.sup.6,
--CF.sub.3, --OSO.sub.2CF.sub.3; R.sup.5 and R.sup.6 are
independently hydrogen, C.sub.1-C.sub.4 alkyl, C(O)R.sup.7,
C(O)NHR.sup.8, C(O)OR.sup.9, SO.sub.2R.sup.10 or may together be
(CH.sub.2).sub.jQ(CH.sub.2).sub.k where Q is O, S, NR.sup.11, or a
bond; j is 2 to 7; k is 0 to 2; R.sup.7, R.sup.8, R.sup.9,
R.sup.10, and R.sup.11 are independently C.sub.1-C.sub.4 alkyl,
aryl, or heteroaryl, or an enantiomer thereof.
[0157] Compounds of formula XIII
##STR00008##
wherein n is 0 or 1; m is 0 or 1; X is oxygen or sulfur; R.sup.1 is
hydrogen or C.sub.1 to C.sub.4 alkyl; R is C.sub.1-C.sub.6 alkyl,
--CH.sub.2--Ar, or Ar; Ar is phenyl optionally substituted with one
to three of the following substitutents: halogen, C.sub.1-C.sub.4
alkyl, or C.sub.1-C.sub.4 alkoxy, or an enantiomer thereof.
[0158] Intermediate compounds also exist in enantiomeric forms and
may be used as purified enantiomers, racemates or mixtures.
[0159] Use of compounds IV, III, II, XIII, X and IX as
intermediates in a synthesis of a ligand for nicotinic
acetylcholine receptors is another aspect of the invention.
[0160] A further aspect of the invention relates to the utility of
compounds of formula I wherein Y is NO as intermediates. These
intermediates are useful in the synthesis of compounds of formula I
wherein Y is N, but their use is not limited to the synthesis of
said compounds.
Pharmaceutical Compositions
[0161] A further aspect of the invention relates to a
pharmaceutical composition for treating or preventing a condition
or disorder as exemplified below arising from dysfunction of
nicotinic acetylcholine receptor neurotransmission in a mammal,
preferably a human, comprising an amount of a compound of formula
I, an enantiomer thereof or a pharmaceutically acceptable salt
thereof, effective in treating or preventing such disorder or
condition and an inert pharmaceutically acceptable carrier.
[0162] For the above-mentioned uses the dosage administered will,
of course, vary with the compound employed, the mode of
administration and the treatment desired. However, in general,
satisfactory results are obtained when the compounds of the
invention are administered at a daily dosage of from about 0.1 mg
to about 20 mg per kg of animal body weight, preferably given in
divided doses 1 to 4 times a day or in sustained release form. For
man, the total daily dose is in the range of from 5 mg to 1,400 mg,
more preferably from 10 mg to 100 mg, and unit dosage forms
suitable for oral administration comprise from 2 mg to 1,400 mg of
the compound admixed with a solid or liquid pharmaceutical carrier
or diluent.
[0163] The compounds of formula I, or an enantiomer thereof, and
pharmaceutically acceptable salts thereof, may be used on their own
or in the form of appropriate medicinal preparations for enteral or
parenteral administration. According to a further aspect of the
invention, there is provided a pharmaceutical composition including
preferably less than 80% and more preferably less than 50% by
weight of a compound of the invention in admixture with an inert
pharmaceutically acceptable diluent or carrier.
[0164] Examples of diluents and carriers are:
[0165] for tablets and dragees: lactose, starch, talc, stearic
acid;
[0166] for capsules: tartaric acid or lactose;
[0167] for injectable solutions: water, alcohols, glycerin,
vegetable oils;
[0168] for suppositories: natural or hardened oils or waxes.
[0169] There is also provided a process for the preparation of such
a pharmaceutical composition that comprises mixing the
ingredients.
Utility
[0170] A further aspect of the invention is the use of a compound
according to the invention, an enantiomer thereof or a
pharmaceutically acceptable salt thereof, in the manufacture of a
medicament for the treatment or prophylaxis of one of the below
mentioned diseases or conditions; and a method of treatment or
prophylaxis of one of the above mentioned diseases or conditions,
which comprises administering a therapeutically effective amount of
a compound according to the invention, or an enantiomer thereof or
a pharmaceutically acceptable salt thereof, to a patient.
[0171] Compounds according to the invention are agonists of
nicotinic acetylcholine receptors. While not being limited by
theory, it is believed that agonists of the .alpha.7 nAChR
(nicotinic acetylcholine receptor) subtype should be useful in the
treatment or prophylaxis of psychotic disorders and intellectual
impairment disorders, and have advantages over compounds which are
or are also agonists of the .alpha.4 nAChR subtype. Therefore,
compounds which are selective for the .alpha.7 nAChR subtype are
preferred. The compounds of the invention are indicated as
pharmaceuticals, in particular in the treatment or prophylaxis of
psychotic disorders and intellectual impairment disorders. Examples
of psychotic disorders include schizophrenia, mania and manic
depression, and anxiety. Examples of intellectual impairment
disorders include Alzheimer's disease, learning deficit, cognition
deficit, attention deficit, memory loss, and Attention Deficit
Hyperactivity Disorder. The compounds of the invention may also be
useful as analgesics in the treatment of pain (including chronic
pain) and in the treatment or prophylaxis of Parkinson's disease,
Huntington's disease, Tourette's syndrome, and neurodegenerative
disorders in which there is loss of cholinergic synapses. The
compounds may further be indicated for the treatment or prophylaxis
of jetlag, for use in inducing the cessation of smoking, and for
the treatment or prophylaxis of nicotine addiction (including that
resulting from exposure to products containing nicotine).
[0172] It is also believed that compounds according to the
invention are useful in the treatment and prophylaxis of ulcerative
colitis.
Pharmacology
[0173] The pharmacological activity of the compounds of the
invention may be measured in the tests set out below:
Test A--Assay for Affinity at .alpha.7 nAChR Subtype
[0174] [.sup.125I]-.alpha.-Bungarotoxin (BTX) Binding to Rat
Hippocampal Membranes.
Rat hippocampi were homogenized in 20 volumes of cold
homogenization buffer (HB: concentrations of constituents (mM):
tris(hydroxymethyl)aminomethane 50; MgCl.sub.2 1; NaCl 120; KCl 5:
pH 7.4). The homogenate was centrifuged for 5 minutes at 1000 g,
the supernatant was saved and the pellet re-extracted. The pooled
supernatants were centrifuged for 20 minutes at 12000 g, washed,
and resuspended in HB. Membranes (30-80 .mu.g) were incubated with
5 nM [.sup.125I].alpha.-BTX, 1 mg/mL BSA (bovine serum albumin),
test drug, and either 2 mM CaCl.sub.2 or 0.5 mM EGTA [ethylene
glycol-bis(.beta.-aminoethylether)] for 2 hours at 21.degree. C.,
and then filtered and washed 4 times over Whatman glass fibre
filters (thickness C) using a Brandel cell harvester. Pretreating
the filters for 3 hours with 1% (BSA/0.01% PEI (polyethyleneimine)
in water was critical for low filter blanks (0.07% of total counts
per minute). Nonspecific binding was described by 100 .mu.M
(-)-nicotine, and specific binding was typically 75%. Test B--Assay
for Affinity to the .alpha.4 nAChR Subtype
[0175] [.sup.3H]-(-)-nicotine binding. Using a procedure modified
from Martino-Barrows and Kellar (Mol Pharm (1987) 31:169-174), rat
brain (cortex and hippocampus) was homogenized as in the
[.sup.125I].alpha.-BTX binding assay, centrifuged for 20 minutes at
12,000.times.g, washed twice, and then resuspended in HB containing
100 .mu.M diisopropyl fluorophosphate. After 20 minutes at
4.degree. C., membranes (approximately 0.5 mg) were incubated with
3 nM [3H]-(-)-nicotine, test drug, 1 .mu.M atropine, and either 2
mM CaCl.sub.2 or 0.5 mM EGTA for 1 hour at 4.degree. C., and then
filtered over Whatman glass fibre filters (thickness C) (pretreated
for 1 hour with 0.5% PEI) using a Brandel cell harvester.
Nonspecific binding was described by 100 .mu.M carbachol, and
specific binding was typically 84%.
Binding Data Analysis for Tests A and B
[0176] IC.sub.50 values and pseudo Hill coefficients (n.sub.H) were
calculated using the non-linear curve-fitting program ALLFIT
(DeLean A, Munson P J and Rodbard D (1977) Am. J. Physiol.,
235:E97-E102). Saturation curves were fitted to a one site model,
using the non-linear regression program ENZFITTER (Leatherbarrow,
R. J. (1987)), yielding K.sub.D values of 1.67 and 1.70 nM for the
.sup.125I-.alpha.-BTX and [.sup.3H]-(-)-nicotine ligands
respectively. K.sub.i values were estimated using the general
Cheng-Prusoff equation:
K.sub.i-[IC.sub.50]/((2+([ligand]/[K.sub.D]).sub.n).sub.1/n-1)
where a value of n=1 was used whenever n.sub.H<1.5 and a value
of n=2 was used when n.sub.H.gtoreq.1.5. Samples were assayed in
triplicate and were typically .+-.5%. K.sub.i values were
determined using 6 or more drug concentrations. The compounds of
the invention are compounds with binding affinities (K.sub.i) of
less than 1000 nM in either Test A or Test B, indicating that they
are expected to have useful therapeutic activity.
[0177] The compounds of the invention have the advantage that they
may be less toxic, be more efficacious, be longer acting, have a
broader range of activity, be more potent, produce fewer side
effects, are more easily absorbed or have other useful
pharmacological properties.
EXAMPLES
[0178] Commercial reagents were used without further purification.
Mass spectra were recorded using either a Hewlett Packard 5988A or
a MicroMass Quattro-1 Mass Spectrometer and are reported as m/z for
the parent molecular ion with its relative intensity. Room
temperature refers to 20-25.degree. C.
Preparation 1
Spiro[1-azabicyclo[2.2.2]octane-3,2'-oxirane]N-borane complex
[0179] A mixture of trimethylsulfoxonium iodide (16.10 g, 73.2,
mmol) and a dispersion of sodium hydride (60% in oil, 3.00 g, 75.0
mmol) in anhydrous dimethyl sulfoxide was stirred at room
temperature under nitrogen for 30 minutes. Quinuclidin-3-one (7.05
g, 56.3 mmol) was then added as a solid portionwise, and the
resulting mixture was stirred at 65-70.degree. C. under nitrogen
for 1 hour. The reaction mixture was cooled, water was added (200
mL), and the resulting solution was extracted with chloroform
(3.times.200 mL). The chloroform extracts were combined, and
back-extracted with water (4.times.200 mL). The chloroform layer
was then dried (MgSO.sub.4), filtered, and evaporated under reduced
pressure to afford spiro[1-azabicyclo[2.2.2]octane-3,2'-oxirane]
(6.51 g, 46.8 mmol, 83%) as a clear, colorless liquid. To a stirred
solution of spiro[1-azabicyclo[2.2.2]octane-3,2'-oxirane] (5.3 g,
38.1 mmol) in anhydrous tetrahydrofuran (100 mL) at 0.degree. C.
was added dropwise a solution of borane in tetrahydrofuran (1.0 M,
38.1 mL, 38.1 mmol), and resulting solution was stirred at
0.degree. C. under nitrogen for 30 minutes. Brine (100 mL) was
added cautiously to the reaction solution, and the resulting
aqueous mixture was extracted with ethyl acetate (2.times.100 mL).
The organic extracts were combined, dried (MgSO.sub.4), filtered,
and evaporated under reduced pressure to afford the title compound
(4.3 g, 28.1 mmol, 74%) as a white solid: electrospray MS 152
([M-H].sup.+, 15).
Preparation 2
3-(2-Chloropyridin-3-ylmethyl)-3-hydroxy-1-azabicyclo[2.2.2]octane
N-borane complex
[0180] A solution of phenyllithium (1.8 M in cyclohexane/ether
[7:3], 167 mL, 0.3 mol, 3 eq.) was added via a cannula to anhydrous
tetrahydrofuran (350 mL) at -60.degree. C. under a nitrogen
atmosphere. Then, diisopropylamine (0.7 mL, 5 mmol) was added
dropwise, followed by a dropwise addition of 2-chloropyridine (28.4
mL, 0.3 mol, 3 eq.) over ten minutes. The resulting solution was
stirred at 40.degree. C. under nitrogen for 1.5 hours. The solution
was then cooled to -60.degree. C., and a solution of
spiro[1-azabicyclo[2.2.2]octane-3,2'-oxirane]N-borane complex (15.3
g, 0.1 mol) in tetrahydrofuran (75 mL) was added dropwise. The
resulting reaction mixture was then stirred at -40.degree. C. under
nitrogen. After 3 hours, a saturated solution of sodium bicarbonate
(150 mL) was slowly added, followed by water (400 mL), and the
resulting aqueous mixture was allowed to warm to room temperature.
The layers were separated and the aqueous phase was extracted with
ethyl acetate (3.times.100 mL). The organic layers were combined,
dried (MgSO.sub.4), filtered, and evaporated under reduced
pressure. Column chromatography using silica gel and elution with
ethyl acetate/hexanes [3:2] afforded the title compound as a tan
solid (17.5 g, 65.6 mmol, 66%): electrospray MS 269 ([MH].sup.+
with .sup.37Cl, 10), 267 ([MH].sup.+ with .sup.35Cl, 26).
Preparation 2(b)
[0181]
3-(2,4-Dichloropyridin-3-ylmethyl)-3-hydroxy-1-azabicyclo[2.2.2]oct-
ane N-borane complex was prepared from 2.64 g (17.8 mmol) of
2,4-dichloropyridine and 1.37 g (8.95 mmol) of
spiro[1-azabicyclo[2.2.2]octane-3,2'oxirane], providing 2.42 g
(90%), m.p. 178-179.degree. C. (1:1 ethyl acetate-hexane).
Preparation 3
Spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]N-borane
complex
[0182]
3-(2-Chloropyridin-3-ylmethyl)-3-hydroxy-1-azabicyclo[2.2.2]octane
N-borane complex (17.4 g, 65.3 mmol) was dissolved in anhydrous
N,N-dimethylformamide (500 mL), the resulting solution was cooled
to 0.degree. C. under nitrogen, and a dispersion of sodium hydride
(60% in oil, 6.55 g, 163 mmol, 2.5 eq.) was added portionwise. The
resulting solution was stirred at room temperature under nitrogen
for 16 hours. A saturated solution of ammonium chloride (50 mL) was
then added at 0.degree. C., followed by ice water (500 mL), and the
resulting aqueous mixture was extracted with chloroform
(4.times.125 mL). The organic extracts were combined, dried
(MgSO.sub.4), and evaporated under reduced pressure to afford an
orange solid. Purification through a short column of silica gel
eluting with chloroform/acetone [95:5 to 85:15], followed by
stirring in hexanes (100 mL) and filtration, provided a yellow
solid (12.7 g, 55.2 mmol, 84%) of the title compound: electrospray
MS 231 ([MH].sup.+, 65).
Preparation 4
3-(2-Methanesulfonyloxyethyl)-3-trimethylsilyloxy-1-azabicyclo[2.2.2]octan-
e N-borane complex
(a) 2-(3-Hydroxy-1-azabicyclo[2.2.2]oct-3-yl)acetic acid t-butyl
ester
[0183] To a solution of diisopropylamine (6.7 mL) in
tetrahydrofuran (THF) (20 mL) at 0.degree. C. was added
n-butyllithium (2.3 M in hexanes; 20 mL). The reaction mixture was
stirred for 40 minutes and then cooled to -78.degree. C. To this
mixture a solution of t-butyl acetate (6.4 mL) in THF (10 mL) was
added dropwise and stirring was continued for an additional 15
minutes. Quinuclidin-3-one (5 g) in THF (15 mL) was added to the
mixture dropwise and the mixture was allowed to warm to 0.degree.
C. over 1 hour. To this solution water (100 mL) was added, the
solution was extracted twice with chloroform and the combined
extracts were washed once with brine. The resulting solution was
dried over MgSO.sub.4, filtered, and evaporated in vacuo to give
9.53 g of the subtitle compound as an off-white solid.
(b) 2-(3-Hydroxy-1-azabicyclo[2.2.2]oct-3-yl)acetic acid methyl
ester
[0184] Trifluoroacetic acid (40 mL) was added dropwise over 15
minutes to a solution of
2-(3-hydroxy-1-azabicyclo[2.2.2]oct-3-yl)acetic acid t-butyl ester
(15.7 g) in anhydrous dichloromethane (40 mL) at 0.degree. C. The
mixture was stirred for 24 hours at room temperature, then the
solvent was evaporated under reduced pressure. The residue was
dissolved in methanol (90 mL) and cooled in an ice bath.
Concentrated sulfuric acid (9 mL) was added dropwise over 10
minutes, then the reaction mixture was stirred at room temperature.
After 3 hours, the solution was poured into 100 mL of ice water,
basified to pH 10 with saturated aqueous sodium carbonate solution,
and extracted with chloroform (4.times.100 mL). The extracts were
dried (MgSO.sub.4), filtered, and evaporated in vacuo to give a
solid. Recrystallization from ethyl acetate provided 6.3 g of the
tan crystalline subtitle compound.
(c) 2-(3-Hydroxy-1-azabicyclo[2.2.2]oct-3-yl)acetic acid methyl
ester N-borane complex
[0185] Borane in THF (1M, 5.25 mL) was added dropwise over 20
minutes to a solution of
2-(3-hydroxy-1-azabicyclo[2.2.2]oct-3-yl)acetic acid methyl ester
(1 g) in anhydrous tetrahydrofuran (THF) (20 mL) stirred at
0.degree. C. After 30 minutes, 20 mL of brine was added, stirring
was continued for a further 30 minutes and the layers were then
separated. The aqueous layer was extracted with ethyl acetate
(2.times.20 mL), the organic layers were combined, and then dried
(MgSO.sub.4), filtered, and evaporated under reduced pressure. The
residue was subjected to flash chromatography on silica gel
(eluting with chloroform/acetone, 95:5) to give the title compound
(900 mg) as an off-white solid.
(d) 3-Hydroxy-3-(2-hydroxyethyl)-1-azabicyclo[2.2.2]octane N-borane
complex
[0186] Under an argon atmosphere, lithium borohydride (2 M in
tetrahydrofuran, 2.6 mL, 5.2 mmol) was added over 5 minutes to a
solution of 2-(3-hydroxy-1-azabicyclo[2.2.2]oct-3-yl)acetic acid
methyl ester N-borane complex (1 g, 4.7 mmol) in anhydrous
tetrahydrofuran (20 mL) and heated at reflux for 1 hour. The
reaction was cooled (ice bath), quenched with water (5 mL) and
saturated aqueous sodium bicarbonate (5 mL), stirred for 45 minutes
at 0.degree. C. to room temperature, and extracted four times with
ethyl acetate. The combined organic layers were dried (MgSO.sub.4),
evaporated under reduced pressure and triturated with ethyl ether
to obtain the title compound (830 mg, 4.5 mmol, 95%) as a white
solid.
(e)
3-Trimethylsilyloxy-3-(2-trimethylsilyloxyethyl)-1-azabicyclo[2.2.2]oc-
tane N-borane complex
[0187] Under an argon atmosphere, chlorotrimethylsilane (0.255 mL,
2 mmol) was added via syringe over 5 minutes to
3-hydroxy-3-(2-hydroxyethyl)-1-azabicyclo[2.2.2]octane N-borane
complex (185 mg, 1 mmol) in dry 1-methylimidazole (1 mL) at
0.degree. C. N-(trimethylsilyl)acetamide (262 mg, 2 mmol) was added
in one portion, the reaction was stirred for 16 hours at room
temperature and heated at 55-60.degree. C. for 3 hours. The mixture
was cooled, poured into ice/water (5 g), and extracted four times
with ether. The combined organic layers were washed four times with
brine, dried (MgSO.sub.4), evaporated under reduced pressure and
purified by flash chromatography (eluting with hexane/ethyl
acetate, 3:2) to obtain the title compound (210 mg, 0.64 mmol,
64%).
(f)
3-(2-Hydroxyethyl)-3-trimethylsilyloxy-1-azabicyclo[2.2.2]octane
N-borane complex
[0188] Under an argon atmosphere,
3-trimethylsilyloxy-3-(2-trimethylsilyloxyethyl)-1-azabicyclo[2.2.2]octan-
e N-borane complex (190 mg, 0.58 mmol) in anhydrous methanol (1 mL)
containing 0.032 M potassium carbonate in methanol (0.25 mL) was
stirred at room temperature for 84 hours, acidified to pH 7 with
acetic acid, and evaporated under reduced pressure. Purification by
flash chromatography (eluting with hexane/ethyl acetate, 3:2)
provided the title compound (94 mg, 0.37 mmol, 63%)
(g)
3-(2-Methanesulfonyloxyethyl)-3-trimethylsilyloxy-1-azabicyclo[2.2.2]o-
ctane N-borane complex
[0189] Under an argon atmosphere, methanesulfonyl chloride (0.086
mL, 1.1 mmol) in anhydrous pyridine (1 mL) was added over 20
minutes at 0.degree. C.-5.degree. C. to a solution of
3-(2-hydroxy-ethyl)-3-trimethylsilyloxy-1-azabicyclo[2.2.2]octane
N-borane complex (257 mg, 1 mmol) in anhydrous pyridine (4 mL),
stirred at 0.degree. C. for 20 minutes, and at room temperature for
2 hours. Poured into ice (15 g), extracted four times with ethyl
acetate, combined the organic layers, and washed sequentially with
1 N aqueous hydrochloric acid (three times), water, and saturated
aqueous sodium bicarbonate. The extracts were dried (MgSO.sub.4),
evaporated under reduced pressure and purified by flash
chromatography (eluting with chloroform/ethyl acetate, 97:3) to
obtain the title compound (263 mg, 0.78 mmol, 78%).
Preparation 5
(a) 3-Ethenyl-3-hydroxy-1-azabicyclo[2.2.2]octane
[0190] Under an argon atmosphere, a solution of 3-quinuclidinone
(1.25 g, 10 mmol) in anhydrous tetrahydrofuran (10 mL) was added
over 15 minutes to a 1 M solution of vinylmagnesium bromide in
tetrahydrofuran (20 mL, 20 mmol) at 0.degree. C. to 5.degree. C.,
stirred at room temperature for 24 hours, cooled to 0.degree. C.,
and acidified to pH 1 with 6 M hydrochloric acid. The mixture was
stirred for 15 minutes, basified to pH 10 with 25% aqueous sodium
hydroxide, extracted with chloroform (4.times.50 mL) and
chloroform/methanol (4:1, 50 mL), combined the organic layers,
dried (MgSO.sub.4), evaporated under reduced pressure and purified
by flash chromatography (eluting with ammoniated
chloroform/methanol, 85:15) to obtain the title compound (830 mg,
5.4 mmol, 54%).
(b) 3-Bromo-2-hydroxypyridine
[0191] A solution of bromine (9.6 g, 60 mmol) in 1 M aqueous
potassium bromide (120 mL) was added over 5 minutes to a solution
of 2-hydroxypyridine (5.7 g, 60 mmol) in 1 M aqueous potassium
bromide (60 mL) and stirred for 24 hours. The solid precipitate was
filtered off, the aqueous phase was saturated with sodium chloride
and extracted with chloroform (4.times.20 mL), the combined
extracts were dried (MgSO.sub.4), evaporated under reduced pressure
and combined with the original precipitate. Purification by flash
chromatography (eluting with ammoniated chloroform/methanol, 95:5)
and recrystallization from acetonitrile provided the title compound
(3.62 g, 20.8 mmol, 35%).
(c) 3-Bromo-2-methoxypyridine
[0192] Under an argon atmosphere, a mixture of
3-bromo-2-hydroxypyridine (3.49 g, 20 mmol), silver carbonate (3.67
g, 13.31 mmol), and iodomethane (1.5 mL, 24.1 mmol) in benzene (30
mL) was stirred in the dark at 40.degree. C. to 50.degree. C. for
24 hours, cooled in an ice bath, and filtered. The filtrate was
washed once with 2% aqueous sodium bicarbonate and twice with
water, dried (MgSO.sub.4), the benzene was evaporated at
atmospheric pressure, and the residue was purified by flash
chromatography (eluting with hexane/ethyl acetate, 2:1) to obtain
the title compound (2.35 g, 12.5 mmol, 62%).
Example 1
Spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
[0193]
5'-Spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]N--
borane complex (12.2 g, 53 mmol) was dissolved in 150 mL of
acetone, the solution was cooled to 0.degree. C., and an aqueous
solution of HBr (24%; 50 mL) was added. The resulting solution was
stirred at room temperature under nitrogen for 24 hours. The
reaction was concentrated under reduced pressure, and the aqueous
residue was treated with saturated aqueous sodium carbonate
solution (50 mL). The solution was basified to pH>10 using solid
sodium carbonate, and the resulting solution was extracted with
chloroform (3.times.100 mL). The organic extracts were combined,
dried (MgSO.sub.4), filtered, and evaporated under reduced pressure
to afford the title compound (11.2 g, 51.8 mmol, 98%, 54% overall)
as an off-white solid: electrospray MS 217 ([MH].sup.+, 72).
[0194] The title compound was separated into its (R)- and
(S)-enantiomers by either of the following methods:
Method A--250 mg of the title compound was separated by chiral
HPLC, using a 2 cm.times.25 cm CHIRALCEL-OD column on a Waters
Delta Prep 3000 Preparative Chromatography System, eluting with
2,2,4-trimethylpentane/ethanol (92:8 to 9:1) at a flow rate of 20
mL/min. This provided 111 mg of the (S)-enantiomer
([.alpha.].sup.23=+59.7.degree. (c=1, methanol)) and 90 mg of the
(R)-enantiomer ([.alpha.].sup.23=-63.9.degree. (c=1, methanol)).
Method B--1 g (4.62 mmol) of the title compound was treated with
L-(+)-tartaric acid (694 mg; 4.62 mmol) in 15% aqueous ethanol (10
mL) and recrystallized three times to obtain the (S)-enantiomer
L-(+)-tartrate (650 mg; 1.77 mmol; [.alpha.].sup.23=+57.7.degree.
(c=2, H.sub.2O)). The filtrates were concentrated under reduced
pressure and the aqueous residue was basified to pH>10 using
solid sodium carbonate. The resulting mixture was extracted with
chloroform (3.times.25 mL) and the combined extracts were dried
(MgSO.sub.4), and evaporated under reduced pressure. The residue
(650 mg; 3 mmol) was treated with D-(-)-tartaric acid (452 mg; 3
mmol) and recrystallized as above to provide the (R)-enantiomer
D-(-)-tartrate (775 mg; 2.11 mmol; [.alpha.].sup.23=-58.2.degree.
(c=2, H.sub.2O)).
Example 2A
5'-Bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
[0195] A solution of
spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine] (100
mg, 0.462 mmol) and sodium acetate (410 mg, 5 mmol) in 50% aqueous
acetic acid (4 mL) was heated to 60.degree. C. Bromine (0.10 mL,
1.94 mmol) was added via a syringe over 10 minutes, and the
solution was then heated under reflux for 1 hour. The mixture was
allowed to cool to ambient temperature, basified to pH>10 with
sodium carbonate, and extracted with chloroform (3.times.15 mL).
The combined extracts were dried (MgSO.sub.4), filtered, and
evaporated under reduced pressure to give the title compound (110
mg, 0.37 mmol, 81%) as an off-white solid: electrospray MS 295
([MH].sup.+, with .sup.79Br, 100), 297 ([MH].sup.+, with .sup.81Br,
98).
Example 2B
(R)-(-)-5'-Bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyrid-
ine]
[0196] The enantiomer
(R)-(-)-spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(1.95 g, 9 mmol) treated in the same way as described in example 2A
provided the title compound (1.77 g, 6 mmol, 67%)
([.alpha.].sup.23=-45.5.degree. (c=1, MeOH)).
Example 3
5'-Phenylspiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
[0197] Under a nitrogen atmosphere,
5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(118 mg, 0.4 mmol), phenylboronic acid (54 mg, 0.443 mmol), and
tetrakis(triphenylphosphine)palladium(0) (11 mg, 2.3 mol %) were
stirred in a solution of 1,2-dimethoxyethane (3 mL) and ethanol
(0.75 mL) containing 2 M aqueous sodium carbonate (0.65 mL, 1.3
mmol). The mixture was heated under reflux for 18 hours. The
reaction mixture was then evaporated under reduced pressure, the
residue was dissolved in chloroform (15 mL), and the extract was
washed with saturated aqueous sodium carbonate (5 mL). The aqueous
layer was extracted with chloroform (2.times.15 mL), and the
organic layers were combined, dried (MgSO.sub.4), filtered, and
evaporated under reduced pressure. Purification by flash
chromatography through silica gel, eluting with ammoniated
chloroform/methanol (95:5 to 9:1), provided the title compound (80
mg, 0.274 mmol, 68%) as a tan solid: electrospray MS 293
([MH].sup.+, 100).
Example 4A
5'-Nitrospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
[0198] A mixture of
spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine] (325
mg, 1.5 mmol) and fuming nitric acid (0.27 mL, 5.74 mmol) in
sulfuric acid (0.75 mL) was heated at 70.degree. C. to 80.degree.
C. for 24 hours. The resulting viscous solution was poured onto 15
g of ice and basified to pH>10 with solid sodium carbonate. The
resulting mixture was extracted with chloroform (4.times.15 mL),
dried (MgSO.sub.4), filtered, and evaporated under reduced
pressure. Purification by flash chromatography through silica gel,
eluting with ammoniated chloroform/methanol (95:5), provided the
title compound (200 mg, 0.765 mmol, 51%) as a light yellow solid:
electrospray MS 262 ([MH].sup.+, 100).
Example 4B
(R)-(-)-5'-Nitrospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyrid-
ine]
[0199]
(R)-(-)-Spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridi-
ne] (3.03 g, 14 mmol) was dissolved in concentrated sulfuric acid
(7 mL) at 0-5.degree. C., fuming nitric acid (3.3 mL, 70.2 mmol)
was added over 10 minutes, the mixture was stirred for 1 hour, and
heated at 65-70.degree. C. for 24 hours. Cooled, poured onto ice
(200 gm), added 300 mL of water, basified to pH 10 with solid
potassium carbonate, stirred for 1 hour, filtered off and dried the
solid title compound (3.6 g, 13.8 mmol, 98%): electrospray MS (m/z,
relative intensity) 262 ([MH].sup.+, 100).
Example 4C
(S)-(+)-5'-Nitrospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyrid-
ine]
[0200] The enantiomer
(S)-(+)-spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(6.5 g, 30 mmol) treated in the same way as described in example 4B
provided the title compound (7.75 g, 29.7 mmol, 99%): electrospray
MS (m/z, relative intensity) 262 ([MH].sup.+, 100).
Example 5
Spiro[1-Azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]quinoline]
[0201] The title compound was prepared by a procedure analogous to
that described in Example 1 from 2-chloroquinoline (0.99 g, 6.06
mmol) and spiro[1-azabicyclo[2.2.2]octane-3,2'-oxirane]N-borane
complex (0.31 g, 2.0 mmol), yielding the title compound (0.135 g)
as a beige powder, electrospray MS 267 [MH].sup.+.
[0202] The two enantiomers were resolved on a Chiral OD column by
elution with an 8-10% EtOH/hexane gradient, and UV detection. First
enantiomer: 100% chiral purity by LC, Rt=12.32 minutes,
[.alpha.].sub.D at 23.degree. in EtOH=+47.9.degree.. Second
enantiomer: 99.4% chiral purity, Rt=17.84 minutes,
[.alpha.].sub.D=-48.5.degree..
Example 6
1'-Chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]isoquinoline-
]
[0203] The title compound was prepared by a procedure analogous to
that described in Example 1 from 1,3-dichloroisoquinoline (2.41 g,
12.2 mmol) and
spiro[1-azabicyclo[2.2.2]octane-3,2'-oxirane]N-borane complex (0.62
g, 4.05 mmol), yielding 0.86 g of
1'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]isoquinolin-
e]N-borane complex, electrospray MS 314 [MH.sup.+]. Removal of the
borane group from 65 mg of the N-borane complex gave 30 mg of the
title compound, electrospray MS 301 [MH.sup.+].
Example 7
Spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]isoquinoline]
[0204] The borane protected chloride of Example 6 (0.3 g or 0.96
mmol) was suspended in a mixture of glacial acetic acid (6.0 mL)
and water (0.5 mL). The suspension was placed under nitrogen and
zinc dust (150 mg) was added. The reaction mixture was stirred at
70.degree. C. for 5 hours. The reaction mixture was allowed to cool
and was then poured into saturated NaHCO.sub.3. Enough aqueous
NaHCO.sub.3 was added to give a basic pH, and the products were
extracted with three portions of chloroform. The combined
chloroform extract was dried (MgSO.sub.4), filtered, and evaporated
in vacuo. Two runs were combined for purification on a silica flash
column, using a gradient from 2:1 hexane/ethyl acetate to 100%
ethyl acetate. The faster eluting compound was
spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]isoquinoline]N-boran-
e complex and the slower eluting compound was the title compound.
Yield 100%: chemical ionization MS 279 [MH].sup.+-H.sub.2 for the
N-borane complex and 267 [MH].sup.+ for the title compound. Removal
of the borane group under the conditions of Example 1 followed by
flash chromatography gave the title compound as a brown semi-solid:
chemical ionization MS 267 [MH].sup.+.
Example 8A
5'-Aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
[0205] A mixture of
5'-nitrospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(1.4 g, 5.36 mmol), and 10% palladium on carbon (48% water wet, 270
mg) in methanol (90 mL) was hydrogenated for 1 hour at 50 psi of
hydrogen. The catalyst was filtered off through a pad of celite and
the solvent was evaporated under reduced to obtain the amine (1.2
g, 5.25 mmol, 98%) as a tan solid: electrospray MS (m/z, relative
intensity) 232 ([MH].sup.+, 100).
[0206] The title compound was separated into its (R)- and
(S)-enantiomers by the following method:
[0207] 150 mg of the title compound was separated by chiral HPLC,
using a 2 cm.times.25 cm CHIRALCEL-OD column on a Waters Delta Prep
4000 Preparative Chromatography System [hexane/ethanol (85:15 to
8:2)] at a flow rate of 20 mL/min. This provided 52 mg of the
(S)-epimer ([.alpha.].sup.22=+62.degree. (c=1, ethanol) and 52 mg
of the (R)-epimer ([.alpha.].sup.23=-64.degree. (c=1, ethanol).
Example 8B
(R)-(-)-5'-Aminospiro[1-azabicyclo-[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyri-
dine]
[0208] The enantiomer
(R)-(-)-5'-nitrospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyri-
dine] (3.8 g, 13.3 mmol) treated in the same way as described in
example 8A, and purified by flash chromatography (eluting with
ammoniated chloroform/methanol, 95:5 to 85:15), provided the title
compound (2.5 g, 10.8 mmol, 81%): electrospray MS (m/z, relative
intensity) 232 ([MH].sup.+, 100).
Example 8C
(S)-(+)-5'-Aminospiro[1-azabicyclo-[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyri-
dine]
[0209] The enantiomer
(S)-(+)-5'nitrospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyrid-
ine] (6.85 g, 26.2 mmol) treated in the same way as described in
example 8A in ammoniated methanol provided the title compound (5.55
g, 24 mmol, 92%): electrospray MS (m/z, relative intensity) 232
([MH].sup.+, 100).
Example 9
5'-Phenylcarboxamidospiro[1-azabicyclo[2.2.2]octane-3,2'
(3'H)-furo[2,3-b]pyridine]
[0210] Under a nitrogen atmosphere, benzoic acid (67 mg, 0.55
mmol), O-(1H-benzotriazol-1-yl)-N,N,N'N'-tetramethyluronium
tetrafluoroborate ("TBTU", 176 mg, 0.55 mmol),
1-hydroxybenzotriazole hydrate ("HOBT", 78 mg, 0.55 mmol), and
diisopropylethylamine (0.193 mL, 1.1 mmol) were combined in
anhydrous N,N-dimethylformamide (8 mL) and stirred for 10 minutes.
5'-Aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyr-
idine] (115 mg, 0.5 mmol) was added as a solid in one portion and
stirring was continued for 3 days. The solvent was evaporated under
high vacuum to 55.degree. C. and the residue was partitioned
between saturated aqueous sodium carbonate (2 mL) and
dichloromethane (10 mL). After separating, the aqueous layer was
extracted with dichloromethane (2.times.5 mL). The organic layers
were combined, dried (MgSO.sub.4), and evaporated under reduced
pressure. Purification by flash chromatography through silica gel,
eluting with ammoniated chloroform/methanol (9:1), provided the
title compound (125 mg, 0.372 mmol, 75%) as a yellow solid:
electrospray MS (m/z, relative intensity) 336 ([MH].sup.+,
100).
Example 10
5'-Phenylaminocarbonylaminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[-
2,3-b]pyridine]
[0211] Under a nitrogen atmosphere, phenyl isocyanate (0.056 mL,
0.515 mmol) was added to a suspension of
5'-aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(119 mg, 0.514 mmol) in anhydrous tetrahydrofuran (5 mL) and
stirred for 12 hours. The solvent was evaporated under reduced
pressure and the residue purified by flash chromatography through
silica gel, eluting with ammoniated chloroform/methanol (92.5:7.5),
to obtain the title compound (155 mg, 0.442 mmol, 86%) as an
off-white solid: electrospray MS (m/z, relative intensity) 351
([MH].sup.+, 100).
Example 11
5'-Phenylsulfonylamidospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b-
]pyridine]
[0212] Under a nitrogen atmosphere, benzenesulfonyl chloride (0.07
mL, 0.55 mmol) was added to a solution of
5'-aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(115 mg, 0.5 mmol) in anhydrous pyridine (5 mL) and stirred for 4
hours. The solvent was evaporated under high vacuum, the residue
was partitioned between saturated aqueous sodium carbonate (2 mL)
and chloroform (10 mL), separated and extracted the aqueous phase
with chloroform (2.times.5 mL). The combined organic layers were
dried (MgSO.sub.4), the solvent was evaporated under reduced
pressure, and the residue was re-evaporated from ethanol
(3.times.10 mL) under reduced pressure. This afforded the title
compound (179 mg, 0.5 mmol, 100%) as a yellow solid: electrospray
MS (m/z, relative intensity) 372 ([MH].sup.+, 100).
Example 12
5'-(N-Methylamino)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyr-
idine]
[0213] Under a nitrogen atmosphere, sodium (50 mg, 2.17 mmol) was
slowly added (exothermic) to methanol (1 mL) and stirred for 1
hour.
5'-Aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(115 mg, 0.5 mmol) and paraformaldehyde (35 mg, 1.17 mmol) were
added and stirred for 16 hours. The reaction was heated at
50.degree. C. for 4 hours, sodium borohydride (53 mg, 1.4 mmol) was
added, and heated at reflux for 1 hour. Then, 1 N aqueous potassium
hydroxide (0.4 mL) was added and continued at reflux for 2 hours
more. The solvent was evaporated under reduced pressure, the
residue was partitioned between water (1 mL) and chloroform (4 mL),
separated and extracted the aqueous phase with chloroform
(2.times.4 mL). The combined organic layers were washed with brine
(1 mL), dried (MgSO.sub.4), evaporated under reduced pressure, and
purified by flash chromatography through silica gel (eluting with
ammoniated chloroform/methanol, 95:5) to obtain the title compound
(78 mg, 0.32 mmol, 64%) as an off-white solid: electrospray MS
(m/z, relative intensity) 246 ([MH].sup.+, 100).
Example 13A
5'-(N,N-Dimethylamino)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b-
]pyridine]
[0214] Sodium cyanoborohydride (63 mg, 1 mmol) was dissolved in
methanol (2.5 mL), anhydrous zinc chloride (69 mg, 0.5 mmol) was
added, stirred for 30 minutes, added the resulting solution to a
solution of
5'-aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(115 mg, 0.5 mmol) and 37% aqueous formaldehyde (0.12 mL, 1.6 mmol)
in methanol (2.5 mL), and stirred for 20 hours. Poured into 1 N
aqueous potassium hydroxide (10 mL), stirred for 1 hour, evaporated
under reduced pressure, and extracted the aqueous residue with
chloroform (4.times.10 mL). The combined extracts were dried
(MgSO.sub.4), evaporated under reduced pressure, and purified by
flash chromatography through silica gel (eluting with ammoniated
chloroform/methanol, 97.5:2.5), to obtain the title compound (85
mg, 0.33 mmol, 66%) as an off-white solid: electrospray MS (m/z,
relative intensity) 260 ([MH].sup.+, 100).
Example 13B
(R)-(-)-5'-(N,N-Dimethylamino)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-fu-
ro[2,3-b]pyridine]
[0215] The enantiomer
(R)-(-)-5'-aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyri-
dine] (231 mg, 1 mmol) treated in the same way as described in
example 13A provided the title compound (178 mg, 0.69 mmol, 69%):
electrospray MS (m/z, relative intensity) 260 ([MH].sup.+,
100).
Example 14A
(S)-(+)-5'-(E)-(Phenylethenyl)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-fu-
ro[2,3-b]pyridine]
[0216] A solution of
(S)-(+)-5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyri-
dine] (150 mg, 0.51 mmol), styrene (0.07 mL, 0.61 mmol),
palladium(II) acetate (1.2 mg, 0.0053 mmol), tri-o-tolylphosphine
(6.4 mg, 0.021 mmol), and triethylamine (0.5 mL, 3.6 mmol) in
anhydrous acetonitrile (0.5 mL), in a heavy-walled threaded glass
tube containing a magnetic stir bar, was purged with argon and
sealed with a Teflon plug and FETFE O-ring. The mixture was stirred
and heated at 100.degree. C. for 2 hours, cooled to room
temperature, dissolved in chloroform (10 mL), washed with saturated
aqueous sodium carbonate (1 mL), dried (MgSO.sub.4), and evaporated
under reduced pressure. Recrystallization from ethyl acetate
afforded the title compound (90 mg, 0.28 mmol, 55%) as a light tan
solid: electrospray MS (m/z, relative intensity) 319 ([MH].sup.+,
100).
Example 14B
(R)-(-)-5'-(E)-(Phenylethenyl)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-fu-
ro[2,3-b]pyridine]
[0217] Treatment of the enantiomer
(R)-(-)-5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyri-
dine] (295 mg, 1 mmol) in the same way as described in example 14A,
and purification by flash chromatography (eluting with ammoniated
chloroform/methanol, 98:2 to 96:4) provided the title compound (132
mg, 0.41 mmol, 41%): electrospray MS (m/z, relative intensity) 319
([MH].sup.+, 100).
Example 15A
(S)-(+)-5'-(4-Morpholino)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,-
3-b]pyridine]
[0218] Sodium tert-butoxide (56.6 mg, 0.59 mmol),
tris(dibenzylideneacetone)dipalladium (15.4 mg, 0.017 mmol), and
2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (21 mg, 0.034 mmol)
were combined in a heavy-walled threaded glass tube containing a
magnetic stir bar, and purged with argon. Added
(S)-(+)-5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'
(3'H)-furo[2,3-b]pyridine] (130 mg, 0.44 mmol), morpholine (0.066
mL, 0.76 mmol) and anhydrous tetrahydrofuran (3 mL), sealed with a
Teflon plug and FETFE O-ring, stirred and heated at 100.degree. C.
for 72 hours. The mixture was cooled to room temperature, dissolved
in chloroform (25 mL), washed with brine (3.times.2 mL), dried
(MgSO.sub.4), evaporated under reduced pressure, purified by flash
chromatography through silica gel (eluting with ammoniated
ether/methanol, 4:1), and recrystallized from ethyl acetate to
obtain the title compound (35 mg, 0.12 mmol, 26%) as a tan solid:
electrospray MS (m/z, relative intensity) 302 ([MH].sup.+,
100).
Example 15B
(R)-(-)-5'-(4-Morpholino)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,-
3-b]pyridine]
[0219] Treatment of the enantiomer
(R)-(-)-5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyri-
dine] (580 mg, 1.965 mmol) in the same way as described in example
15A, provided the title compound (187 mg, 0.62 mmol, 32%):
electrospray MS (m/z, relative intensity) 302 ([MH].sup.+,
100).
Example 16
(R)-(-)-5'-(1-Azetidinyl)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,-
3-b]pyridine]
[0220]
(R)-(-)-5'-Bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3--
b]pyridine] (295 mg, 1 mmol), azetidine (0.101 mL, 1.5 mmol),
sodium tert-butoxide (135 mg, 1.4 mmol),
tris(dibenzylideneacetone)dipalladium (46 mg, 0.05 mmol),
2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (62 mg, 0.1 mmol) and
anhydrous tetrahydrofuran (9 mL) were combined in a heavy-walled
threaded glass tube containing a magnetic stir bar, purged with
argon, and sealed with a Teflon plug and FETFE O-ring. The mixture
was stirred and heated at 75.degree. C. for 4 hours, cooled to room
temperature, dissolved in chloroform (20 mL), washed with brine
(3.times.10 mL), dried (MgSO.sub.4), evaporated under reduced
pressure, and purified by flash chromatography through silica gel
(eluting with ammoniated chloroform/methanol 95:5) to procure the
title compound (230 mg, 0.0.85 mmol, 85%) as a light tan solid:
chemical ionization MS (m/z, relative intensity) 272 ([MH].sup.+,
56).
Example 17
(R)-(-)-5'-(2-(4-Pyridyl)ethenyl)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-
-furo[2,3-b]pyridine]
[0221]
(R)-(-)-5'-Bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3--
b]pyridine] (295 mg, 1 mmol), 4-vinylpyridine (0.135 mL, 1.25
mmol), palladium(II) acetate (7.2 mg, 0.032 mmol),
tri-o-tolylphosphine (38.7 mg, 0.127 mmol), and triethylamine (0.5
mL, 3.6 mmol) in anhydrous acetonitrile (0.5 mL) were combined in a
heavy-walled threaded glass tube containing a magnetic stir bar,
purged with argon and sealed with a Teflon plug and FETFE O-ring.
The mixture was stirred and heated at 100 to 105.degree. C. for 48
hours, cooled to room temperature, dissolved in chloroform (25 mL),
washed with saturated aqueous sodium carbonate (2 mL), dried
(MgSO.sub.4), and evaporated under reduced pressure. Purification
by flash chromatography through silica gel (eluting with ammoniated
chloroform/methanol, 95:5), followed by recrystallization from
acetone afforded the title compound (230 mg, 0.72 mmol, 72%):
electrospray MS (m/z, relative intensity) 320 ([MH].sup.+,
100).
Example 18
(R)-(-)-5'-(2-(2-Pyridyl)ethenyl)spiro[1-azabicyclo[2.2.2]octane-3,2'
(3'H)-furo[2,3-b]pyridine]
[0222]
(R)-(-)-5'-Bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3--
b]pyridine] (150 mg, 0.5 mmol) was treated with 2-vinylpyridine
(0.070 mL, 0.65 mmol) in the same way as described in example 16.
Purification by flash chromatography through silica gel (eluting
with ammoniated ether/methanol, 95:5 to 9:1), followed by
recrystallization from acetonitrile produced the title compound (37
mg, 0.12 mmol, 23%): electrospray MS (m/z, relative intensity) 320
([MH].sup.+, 100).
Example 19
(R)-(-)-5'-(2-Trimethylsilylethynyl)spiro[1-azabicyclo[2.2.2]octane-3,2'(3-
'H)-furo[2,3-b]pyridine]
[0223]
(R)-(-)-5'-Bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3--
b]pyridine] (295 mg, 1 mmol), trimethylsilylacetylene (0.355 mL,
2.5 mmol), tetrakis(triphenylphosphine)palladium (230 mg, 0.2
mmol), triethylamine (2 mL) and anhydrous acetonitrile (2 mL) were
combined in a heavy-walled threaded glass tube containing a
magnetic stir bar, purged with argon and sealed with a Teflon plug
and FETFE O-ring. The mixture was stirred and heated at 100.degree.
C. for 4 hours, cooled to room temperature, dissolved in chloroform
(25 mL), washed with saturated aqueous sodium carbonate (2 mL),
dried (MgSO.sub.4), and evaporated under reduced pressure.
Purification by flash chromatography through silica gel (eluting
with ammoniated ether/methanol, 9:1) afforded the title compound
(280 mg, 0.90 mmol, 90%): chemical ionization MS (m/z, relative
intensity) 313 ([MH].sup.+, 30).
Example 20
(R)-(-)-5'-Ethynylspiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyr-
idine]
[0224] Under an argon atmosphere, a 1 M solution of
tetrabutylammonium fluoride in tetrahydrofuran (1.3 mL, 1.3 mmol)
was added at 0.degree. C. to a solution of
(R)-(-)-5'-(2-trimethylsilylethynyl)spiro[1-azabicyclo[2.2.2]octane-3,2'(-
3'H)-furo[2,3-b]pyridine] (265 mg, 0.85 mmol) in anhydrous
tetrahydrofuran (5 mL), and stirred at room temperature for 2
hours. The reaction was quenched with saturated aqueous ammonium
chloride solution (2 mL), extracted with ether (5.times.15 mL),
dried (MgSO.sub.4), evaporated under reduced pressure, and purified
by flash chromatography through silica gel (eluting with ammoniated
chloroform/methanol, 95:5) to obtain the title compound (121 mg,
0.50 mmol, 59%): chemical ionization MS (m/z, relative intensity)
241 ([MH].sup.+, 19).
Example 21
5'-(2-Furyl)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
[0225] A solution containing
5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(103.5 mg, 0.351 mmol), tris(dibenzylidineacetone)dipalladium (0)
(14 mg, 0.015 mmol), tri(o-tolyl)phosphine (44.4 mg, 0.146 mmol),
lithium chloride (62 mg, 1.46 mmol), and
2-(tri-n-butylstannyl)furan (0.17 g, 0.476 mmol) in
1,2-dimethoxyethane (1 mL) was heated under reflux for 2 h. The
solution was evaporated, and the residue was taken up in chloroform
and filtered. The filtrate was evaporated then purified by HPLC
using a gradient of 0-25% 1:1:2 7M methanolic
ammonia:methanol:chloroform and chloroform to obtain the title
compound (89 mg, 0.313 mmol, 89%) as a pale solid: electrospray MS
(m/z, relative intensity) 283 ([MH].sup.+, 100).
Example 22
5'-(3-Pyridyl)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridin-
e]
[0226] A solution containing
5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(158 mg, 0.535 mmol), tris(dibenzylidineacetone)dipalladium (0) (23
mg, 0.025 mmol), tri(o-tolyl)phosphine (66 mg, 0.217 mmol), lithium
chloride (99 mg, 2.34 mmol), and 3-(tri-n-butylstannyl)pyridine
(0.3 mL, approx. 0.3 g, approx. 0.82 mmol) in 1,2-dimethoxyethane
(2 mL) was heated under reflux for 6 h. The solution was
evaporated, and the residue was taken up in chloroform and
filtered. The filtrate was evaporated then purified by HPLC using a
gradient of 0-20% 1:1:2 7M methanolic ammonia:methanol:chloroform
and chloroform to obtain the title compound (58 mg, 0.198 mmol,
37%) as a pale solid: electrospray MS (m/z, relative intensity) 294
([MH].sup.+, 80), 273 (100).
Example 23
5'-Methylspiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
[0227] A solution containing
5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'
(3'H)-furo[2,3-b]pyridine] (203 mg, 0.687 mmol),
tris(dibenzylidineacetone)dipalladium (0) (33 mg, 0.036 mmol),
tri(o-tolyl)phosphine (95 mg, 0.312 mmol), lithium chloride (241
mg, 5.69 mmol), and tetramethylstannane (1.0 mL, 1.3 g, 7.2 mmol)
in 2-methoxyethyl ether (5 mL) was heated in a bath maintained at
100.degree. C. After 3 h, a further portion of tetramethylstannane
(1 mL, 1.3 g, 7.2 mmol) was added, and heating was continued
overnight. The solution was filtered, and subjected to purification
by HPLC using a gradient of 0-20% 1:1:2 7M methanolic
ammonia:methanol:chloroform and chloroform to obtain the title
compound (120 mg, 0.519 mmol, 76%) as a pale solid: electrospray MS
(m/z, relative intensity) 231 ([MH].sup.+, 100).
Example 24
Spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-5'-carbonitr-
ile] and
Spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-5'--
carboxamide]
[0228] A solution containing
5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'
(3'H)-furo[2,3-b]pyridine] (165 mg, 0.558 mmol), and copper (I)
cyanide (600 mg, 1.3 g, approx. 7.2 mmol) in
1-methyl-2-pyrrolidinone (5 mL) was heated in a bath maintained at
180.degree. C. overnight and was then allowed to cool. The solution
was then partitioned between aqueous ammonia and chloroform, and
the organic layer was separated, then dried (MgSO.sub.4), filtered,
and evaporated. The residue was subjected to purification by HPLC
using a gradient of 0-20% 1:1:2 7M methanolic
ammonia:methanol:chloroform and chloroform to give
spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-5'-carbonit-
rile] (52 mg, 0.216 mmol, 39%) as a pale solid: DCI MS (m/z,
relative intensity) 242 ([MH].sup.+, 100), and
spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-5'-carboxam-
ide] (71 mg, 0.274 mmol, 49%) as a pale solid: electrospray MS
(m/z, relative intensity) 260 ([MH].sup.+, 100).
Example 25
5'-Ethenylspiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
[0229] A solution containing
5'-bromospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(150 mg, 0.508 mmol), tris(dibenzylidineacetone)dipalladium (0) (22
mg, 0.024 mmol), tri(o-tolyl)phosphine (63 mg, 0.206 mmol), lithium
chloride (103 mg, 2.43 mmol), and tri-n-butylvinylstannane (188 mg,
0.592 mmol) in 1,2-dimethoxyethane (10 mL) was heated under reflux
overnight. The solution was evaporated, and the residue was taken
up in chloroform and filtered. The filtrate was evaporated then
purified by HPLC using a gradient of 0-25% 1:1:2 7M methanolic
ammonia:methanol:chloroform and chloroform to obtain the title
compound (93 mg, 0.385 mmol, 76%) as a pale solid: electrospray MS
(m/z, relative intensity) 243 ([MH].sup.+, 100).
Example 26
(R)-(-)-5'-N'-(3-Chlorophenyl)aminocarbonylaminospiro[1-azabicyclo[2.2.2]o-
ctane-3,2'(3'H)-furo[2,3-b]pyridine]
[0230] The
(R)-(-)-5'-Aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[-
2,3-b]pyridine] (65 mg or 0.28 mmoles) was suspended in 2.7 mL of
anhydrous tetrahydrofuran under nitrogen atmosphere. The
3-chlorophenylisocyanate (35 .mu.L) was added and the suspension
was stirred at ambient temperature for 5 hours. The tetrahydrofuran
was removed in vacuo and the crude was purified by flash
chromatography. Elution with 20-40% methanol/chloroform (ammoniated
with NH.sub.4OH) gave the desired product spot product. The
solvents were removed in vacuo and the residue was taken up in
chloroform and dried (MgSO.sub.4). Evaporating, chasing with two
portions of ether, left 100 mg (92%) of white solid. Electrospray
MS 385 and 387 [MH].sup.+.
Example 27
(R)-(-)-5'-N'-(2-Nitrophenyl)aminocarbonylaminospiro[1-azabicyclo[2.2.2]oc-
tane-3,2'(3'H)-furo[2,3-b]pyridine]
[0231] Using the same method as in example 27 but substituting
2-nitrophenyl isocyanate for 3-chlorophenylisocyanate the title
compound was prepared; yield 97 mg (88%) of yellow powder.
Electrospray MS 396 [MH].sup.+.
Example 28
(R)-(-)-5'-N,N-Diethylaminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[-
2,3-b]pyridine]
[0232] Sodium cyanoborohydride (190 mg or 3.0 mmoles) and the zinc
chloride (206 mg or 1.5 mmoles) were added to 3.0 mL of anhydrous
methanol under nitrogen atmosphere. Stirring for 5 minutes gave
complete dissolution. The
(R)-(-)-5'-aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyri-
dine] (230 mg or 1.0 mmol) was added followed by acetaldehyde
(0.335 mL or 6.0 mmoles.) The suspension was stirred at ambient
temperature for 16 hours. The methanol was concentrated in vacuo
and the suspension was poured into 20 mL of 1 N sodium hydroxide.
The aqueous layer was extracted with four 20 mL portions of
chloroform, and these were combined dried (MgSO.sub.4) and
evaporated in vacuo. The crude was purified by flash
chromatography, starting with 6/3/1/0.1 ethyl
acetate/methanol/water (ammoniated with NH.sub.4OH) and then to
3/6/1/0.1. The solvents were removed in vacuo and the residue was
taken up in chloroform and dried (MgSO.sub.4.) Obtained 0.227 g
(79%) of light brown syrup. Electrospray MS 288 [MH].sup.+.
Example 29
(R-(-)-5'-N-Ethylaminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b-
]pyridine]
[0233]
(R)-(-)-5'-Aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3--
b]pyridine] (230 mg or 1.0 mmoles) and sodium cyanoborohydride were
suspended in 6.2 mL of anhydrous methanol. The acetaldehyde (90
.mu.L or 1.1 mmoles) and the solution was stirred at ambient
temperature for 16 hours. The methanol was removed in vacuo and the
residue was taken up in 2 mL of water and 8 mL of chloroform. The
layers were separated and the aqueous layer was extracted 3 times
more. The combined organic layers were dried (MgSO.sub.4) and
evaporated in vacuo. The crude product was purified by flash
chromatography using a 3-15% methanol/chloroform (ammoniated)
gradient. The solvents were evaporated in vacuo and chased with two
portions of ether. The residue was suspended in ether and collected
by filtration. After washing with ether and drying with high vacuum
obtained 81 mg (31%) of white powder. Electrospray MS 260
[MH].sup.+.
Example 30
(R)-(-)-5'-N-Benzylaminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-
-b]pyridine]
[0234] Prepared by the method of example 12. From 1.0 mmoles
obtained 247 mg (77%) of white powder. Electrospray MS 322
[MH].sup.+.
Example 31
(R)-(-)-5'-N-Formamidospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b-
]pyridine]
[0235] 98% Formic acid (2.1 mL) and acetic anhydride (0.7 mL) were
combined under nitrogen atmosphere and cooled with an ice bath. The
(R)-(-)-5'-aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyri-
dine] (230 mg or 1.0 mmoles) was added and the reaction was allowed
to warm to ambient temperature. The reaction was stirred for 26
hours and then was poured with stirring into saturated sodium
carbonate. Solid Na.sub.2CO.sub.3 was added until the pH was basic
again, and then the aqueous layer was extracted with four portions
of chloroform. These were combined, dried (MgSO.sub.4) and
evaporated in vacuo. The crude was purified by flash chromatography
eluting with a 2-10% ammoniated methanol/chloroform gradient. The
solvents were removed in vacuo and the residue was taken up in
chloroform, dried (MgSO.sub.4) and evaporated in vacuo. The solvent
was chased with two portions of ether giving 0.2 g (77%) of white
solid. Electrospray MS 260 [MH].sup.+.
Example 32
(R)-(-)-5'-N-Acetamidospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b-
]pyridine]
[0236]
(R)-(-)-5'-Aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3--
b]pyridine] (230 mg or 1.0 mmoles) was dissolved in 3 mL anhydrous
pyridine under nitrogen atmosphere. The acetic anhydride (0.1 mL or
1.1 mmoles) was added and the solution was heated at 100.degree. C.
for 40 hours. The pyridine was removed in vacuo, and the residue
was taken up in 8 mL chloroform and washed with 4 mL of saturated
sodium bicarbonate. The aqueous layer was extracted twice more with
chloroform and the combined organic layers were dried (MgSO.sub.4)
and evaporated in vacuo. Purification by flash chromatography using
a 3-20% ammoniated methanol/chloroform gradient gave the desired
product. The solvents were removed in vacuo and chased with two
portions of ether. Obtained 154 mg (56%) of white solid. Chemical
ionization MS 274 [MH].sup.+.
Example 33
4'-Chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
and
4'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[3,2-c]pyridin-
e]
[0237]
4'-Chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyrid-
ine]borane complex and
2'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[3,2-c]pyridine]bo-
rane complex were prepared from 2.36 g (7.84 mmol)
3-(2,4-dichloropyridin-3-ylmethyl)-3-hydroxy-1-azabicyclo[2.2.2]octane
N-borane complex and 319 mg (7.97 mmol) of sodium hydride in
dimethylformamide as in Preparation 2. This mixture was treated
with aqueous hydrobromic acid in acetone to provide, following
flash chromatography on neutral silica gel using a mixture of 98:2
ammoniated chloroform/methanol, 559 mg of
4'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine],
m.p. 109-110.degree. C. (ethyl ether), and 463 mg of
4'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[3,2-c]pyridine],
m.p. 113-115.degree. C.
Example 34
Spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[3,2-c]pyridine]
[0238] The
4'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[3,2-c]p-
yridine] (125 mg or 5.0 mmol) from Example 33 was dissolved in 50
mL of anhydrous methanol, and 25 mg of 10% palladium on carbon was
added. The bottle was placed on the Parr apparatus under hydrogen
atmosphere and shaken for 2.5 hours. The Pd/C was removed by
filtration and washed with methanol. The solvent was removed in
vacuo and the residue was taken up in chloroform and methanol and
transferred to a vial. The solvent was removed in vacuo and chased
with two portions of ether. After drying with high vacuum obtained
112 mg of off-white powder (104% with residual solvent).
Electrospray MS 217 [MH].sup.+
Example 35
4'-Methoxyspiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
[0239] Sodium hydride (241 mg, 6.0 mmol) was added to a solution of
76 mg (0.30 mmol) of
4'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
in 25 mL of ice-cold methanol, under a nitrogen atmosphere. The
resulting solution was heated to reflux and stirred for 4 days,
then cooled to ambient temperature, poured into 30 mL of water, and
extracted with chloroform (3.times.30 mL). The combined organic
extract was dried over anhydrous magnesium sulfate, concentrated in
vacuo and the residue flash chromatographed on neutral silica gel
using a 9:1 mixture of ammoniated chloroform/methanol to give 50 mg
(67%) of the title compound as a white solid: electrospray MS (m/z,
relative intensity) 247 ([MH].sup.+).
Example 36
4'-Phenylthiospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-
]
[0240] Sodium hydride (151 mg, 3.77 mmol) was added to a solution
of 97 mg (0.387 mmol) of
4'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine],
0.40 mL (3.91 mmol) of thiophenol and 0.10 mL of methanol in 15 mL
of dioxane, under a nitrogen atmosphere. The reaction was refluxed
for 4 days, cooled to ambient temperature, diluted with 30 mL of
water, and extracted with chloroform (3.times.30 mL). The combined
organic extract was dried over anhydrous magnesium sulfate,
concentrated in vacuo and the residue flash chromatographed on
neutral silica gel using a 98:2 mixture of ammoniated
chloroform/methanol to give 65 mg (52%) of the title compound as a
colourless oil: electrospray MS (m/z, relative intensity) 325
([MH].sup.+).
Example 37
4'-(N-2-Aminoethyl)aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-
-b]pyridine]
[0241] A solution of 74 mg (0.295 mmol) of
4'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
in 10 mL of ethylenediamine was heated to reflux under a nitrogen
atmosphere and stirred for 4 days. Upon cooling to ambient
temperature, the solvent was removed in vacuo. The residue was
dissolved in 20 mL of saturated aqueous sodium carbonate and
extracted with chloroform (3.times.25 mL). The combined organic
extract was dried over anhydrous magnesium sulfate and concentrated
in vacuo to give the title compound as a dark oil, 80 mg (100%):
electrospray MS (m/z, relative intensity) 275 ([MH].sup.+).
Example 38
4'-(4-N-Methylpiperazin-1-yl)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-fur-
o[2,3-b]pyridine]
[0242] A solution of 97 mg (0.387 mmol) of
4'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
in 1 mL of 1-methylpiperazine was heated to reflux under a nitrogen
atmosphere and stirred for 18 hours. Upon cooling to ambient
temperature, the diluted with 40 mL of water, basicified with 2 mL
of saturated aqueous sodium carbonate and extracted with chloroform
(3.times.25 mL). The combined organic extract was dried over
anhydrous magnesium sulfate, concentrated in vacuo, and flash
chromatographed on neutral silica gel using a 4:1 mixture of
ammoniated chloroform/methanol to provide 59 mg (48%) of the title
compound as an amber oil: electrospray MS (m/z, relative intensity)
315 ([MH].sup.+).
Example 39
4'-(Phenylmethyl)aminospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b-
]pyridine]
[0243] A solution of 97 mg (0.387 mmol) of
4'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
in 5 mL of benzylamine was heated to reflux under a nitrogen
atmosphere and stirred for 18 hours. Upon cooling to ambient
temperature, the diluted with 40 mL of water, basicified with 2 mL
of saturated aqueous sodium carbonate and extracted with chloroform
(3.times.25 mL). The combined organic extract was dried over
anhydrous magnesium sulfate, concentrated in vacuo, and flash
chromatographed on neutral silica gel using a 9:1 mixture of
ammoniated chloroform/methanol to provide 42 mg (34%) of the title
compound as a white solid: electrospray MS (m/z, relative
intensity) 322 ([MH].sup.+).
Example 40
4'-(Methylamino)spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyrid-
ine]
[0244] A solution of 151 mg (0.60 mmol) of
4'-chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
in 25 mL of 40% aqueous methylamine was heated to 175.degree. C. in
a steel bomb for 18 hours, then cooled to ambient temperature and
concentrated in vacuo. The residue was dissolved in 10 mL of
ethanol containing 0.4 mL of concentrated hydrochloric acid and the
solution was allowed to stand overnight. After filtering, the
solution was concentrated in vacuo and the residue crystallized
from isopropanol, giving 147 mg of the title compound as a white
solid: electrospray MS (m/z, relative intensity) 246
([MH].sup.+).
Example 41
Spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-7'-oxide]
[0245] A solution of
spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(2.88 g, 13.3 mmol) and aqueous hydrogen peroxide (30%, 5 mL) in
acetic acid (20 mL) was heated under reflux. After 16 h and 24 h,
further portions of hydrogen peroxide were added, and heating was
continued for a total of 48 h. The solution was then evaporated,
then the residue was redissolved in ethanol (40 mL) which had been
saturated with sulfur dioxide. After 4 h the solution was
evaporated and the residue was purified by HPLC on silica using as
the eluant a 0-50% gradient of a mixture of solvents (7 M
methanolic ammonia (25%) methanol (25%) chloroform (50%)) and
chloroform. The title compound (934 mg, 4.0 mmol, 30%) was a solid:
DCI MS 233 ([MH].sup.+).
Example 42
Spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-6'-carbonitr-
ile]
[0246] A solution of
spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-7'-oxide]
(95 mg, 0.41 mmol) was dissolved in acetonitrile (2 mL).
Triethylamine (0.12 mL, 87 mg, 0.86 mmol), and then trimethylsilyl
cyanide (0.2 mL, 149 mg, 1.5 mmol) were added. The solution was
stirred at room temperature overnight, then heated to reflux
temperature. After approx. 8 h, further trimethylsilyl cyanide (0.2
mL) was added. After heating under reflux overnight the solution
was allowed to cool. Excess methanol was added, and the solution
was left at room temperature for 4 h then evaporated. The residue
was purified by HPLC on silica using as the eluant a 0-25% gradient
of a mixture of solvents (7 M methanolic ammonia (25%) methanol
(25%) chloroform (50%)) and chloroform. The title compound (50 mg,
0.21 mmol, 51%) was a solid: electrospray MS 242 ([MH].sup.+)
Example 43
6'-Chlorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
[0247] A solution of
spiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-7'-oxide]
(98 mg, 0.42 mmol) in phosphorous oxychloride (2 mL) was heated
under reflux for 2 h. The solution was evaporated, the residue was
partitioned between aqueous potassium carbonate and chloroform,
then the organic layer was dried (MgSO.sub.4), filtered, and
evaporated. The residue was purified by HPLC on silica using as the
eluant a 0-25% gradient of a mixture of solvents (7M methanolic
ammonia (25%) methanol (25%) chloroform (50%)) and chloroform. The
title compound (26 mg, 0.10 mmol, 25%) was a solid: electrospray MS
251 ([MH].sup.+ with .sup.35Cl) and 253 ([MH].sup.+ with
.sup.37Cl).
Example 44
6'-Fluorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine]
(a)
6'-Fluorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-
]N-borane complex
[0248] A solution of phenyllithium (1.8 M in cyclohexane, 13.5 mL)
was added to THF (15 mL) under argon. Diisopropylamine (0.5 mL) was
added, and the solution was cooled to -78.degree. C. (dry
ice/acetone bath temperature). To the resulting solution,
2,6-difluoropyridine (1.23 mL, 1.56 g, 13.6 mmol) was added
dropwise, then after 1 h, a solution of
spiro[1-azabicyclo[2.2.2]octane-3,2'-oxirane]N-borane complex (765
mg, 5.0 mmol) in tetrahydrofuran was added dropwise. The solution
was stirred at -78.degree. C. for 1 h and the cooling bath was then
replaced with a dry ice/acetonitrile bath. The solution was then
stirred overnight, warming to room temperature. Saturated aqueous
sodium bicarbonate was added, and the solution was then extracted
with chloroform. The extract was then dried (MgSO.sub.4), filtered,
and evaporated. The residue was dissolved in DMF (20 mL), and was
then added to a suspension of hexane-washed sodium hydride (60%
mixture with mineral oil, 507 mg, 12.7 mmol) in DMF (20 mL) stirred
at 0.degree. C. The solution was stirred overnight, warming to room
temperature. Saturated aqueous sodium bicarbonate was added to the
solution, which was then extracted with chloroform. The extract was
then dried (MgSO.sub.4), filtered, and evaporated, and the residue
was purified by HPLC using a gradient of 5-50% ethyl acetate and
hexane to give the sub-title compound (102 mg, 8%, 0.41 mmol):
electrospray MS (m/z) 247 [M-H].sup.+.
(b)
6'-Fluorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyridine-
]
[0249]
6'-Fluorospiro[1-azabicyclo[2.2.2]octane-3,2'(3'H)-furo[2,3-b]pyrid-
ine]N-borane complex (98 mg, 0.40 mmol) was dissolved in acetone (5
mL). 48% Aqueous hydrobromic acid (2 mL) was diluted with water (2
mL) and then was added to the solution. The resulting mixture was
stirred at room temperature overnight. The solution was then
evaporated and partitioned between aqueous sodium carbonate and
chloroform. The organic extract was then dried (MgSO.sub.4),
filtered, and evaporated, and the residue was purified by HPLC
using a gradient of 0-25% 1:1:2 7 M methanolic
ammonia:methanol:chloroform and chloroform to give the title
compound (39 mg, 0.168 mmol, 43%) as a solid: electrospray MS (m/z,
relative intensity) 235 ([MH].sup.+, 100).
* * * * *