U.S. patent application number 11/638704 was filed with the patent office on 2010-05-20 for antibacterial agents.
This patent application is currently assigned to British Biotech Pharmaceuticals Ltd.. Invention is credited to Kenneth Noel Keavey, Laurent Mounier, Gilles Denis Pain, Lisa Marie Pratt.
Application Number | 20100125075 11/638704 |
Document ID | / |
Family ID | 26315838 |
Filed Date | 2010-05-20 |
United States Patent
Application |
20100125075 |
Kind Code |
A1 |
Pratt; Lisa Marie ; et
al. |
May 20, 2010 |
Antibacterial Agents
Abstract
Compounds of formula (II) are antibacterial agents wherein Q
represents a radical of the formula: --N(OH)CH(.dbd.O) or the
formula: --C(.dbd.O)NH(OH); R.sub.1 represents hydrogen,
C.sub.1-C.sub.6 alkyl or C.sub.1-C.sub.6 alkyl substituted by one
or more halogen atoms, or, except when Q is a radical of the
formula: --N(OH)CH(.dbd.O), a hydroxy, C.sub.1-C.sub.6 alkoxy,
C.sub.1-C.sub.6 alkenyloxy, amino, C.sub.1-C.sub.6 alkylamino, or
di-(C.sub.1-C.sub.6 alkylamino group; R.sub.2 represents a
substituted or unsubstituted C.sub.1-C.sub.6 alkyl,
cycloalkyl(C.sub.1-C.sub.6 alkyl)- or aryl(C.sub.1-C.sub.6
alkyl)-group; and A represents a group of formula (IIA), or (IIB)
wherein R.sub.4 represents the side chain of a natural or
non-natural alpha amino acid, and R.sub.5 and R.sub.6 when taken
together with the nitrogen atom to which they are attached form a
saturated heterocyclic first ring of 5 to 7 atoms as specified in
the description.
Inventors: |
Pratt; Lisa Marie; (Cowley,
GB) ; Keavey; Kenneth Noel; (Cowley, GB) ;
Pain; Gilles Denis; (Cowley, GB) ; Mounier;
Laurent; (Cowley, GB) |
Correspondence
Address: |
BANNER & WITCOFF, LTD.
1100 13th STREET, N.W., SUITE 1200
WASHINGTON
DC
20005-4051
US
|
Assignee: |
British Biotech Pharmaceuticals
Ltd.
Cowley
GB
|
Family ID: |
26315838 |
Appl. No.: |
11/638704 |
Filed: |
December 14, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10953788 |
Sep 30, 2004 |
7186719 |
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11638704 |
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10049131 |
Jul 10, 2002 |
6846825 |
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PCT/GB00/03078 |
Aug 10, 2000 |
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10953788 |
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Current U.S.
Class: |
514/235.8 ;
514/235.5; 514/252.11; 514/252.13; 514/252.14; 514/253.01;
514/253.1; 514/253.13; 514/254.03; 514/254.04; 514/254.05;
514/254.09; 514/254.1; 514/254.11; 514/255.01; 514/307; 514/315;
514/322; 514/326; 514/330; 544/121; 544/130; 544/295; 544/357;
544/360; 544/364; 544/365; 544/367; 544/369; 544/371; 544/372;
544/373; 544/377; 544/379; 544/386; 544/391; 546/146; 546/188;
546/208; 546/210; 546/211; 546/221; 546/226; 546/245 |
Current CPC
Class: |
C07D 317/58 20130101;
C07D 209/08 20130101; C07D 307/68 20130101; C07D 317/68 20130101;
C07D 211/46 20130101; C07D 295/185 20130101; C07D 401/04 20130101;
C07D 211/22 20130101; C07D 213/74 20130101; C07D 405/14 20130101;
A61P 31/04 20180101; C07D 213/38 20130101; C07D 211/16 20130101;
C07D 217/06 20130101; C07D 295/192 20130101; C07D 239/42 20130101;
Y02P 20/582 20151101; C07D 211/32 20130101 |
Class at
Publication: |
514/235.8 ;
546/226; 546/210; 544/377; 544/391; 544/379; 546/211; 546/146;
544/295; 544/386; 546/245; 544/360; 544/373; 544/357; 544/371;
544/365; 544/367; 544/364; 544/369; 544/372; 544/121; 546/221;
544/130; 546/188; 546/208; 514/330; 514/322; 514/255.01; 514/254.1;
514/307; 514/252.14; 514/254.11; 514/253.01; 514/254.09;
514/252.11; 514/254.05; 514/253.13; 514/254.04; 514/252.13;
514/254.03; 514/253.1; 514/235.5; 514/326; 514/315 |
International
Class: |
A61K 31/5377 20060101
A61K031/5377; C07D 211/32 20060101 C07D211/32; C07D 401/04 20060101
C07D401/04; C07D 405/10 20060101 C07D405/10; C07D 241/04 20060101
C07D241/04; C07D 405/06 20060101 C07D405/06; C07D 405/14 20060101
C07D405/14; C07D 217/20 20060101 C07D217/20; C07D 403/04 20060101
C07D403/04; C07D 211/22 20060101 C07D211/22; C07D 403/10 20060101
C07D403/10; C07D 403/06 20060101 C07D403/06; C07D 401/06 20060101
C07D401/06; C07D 413/06 20060101 C07D413/06; C07D 417/14 20060101
C07D417/14; C07D 417/06 20060101 C07D417/06; C07D 413/10 20060101
C07D413/10; C07D 211/46 20060101 C07D211/46; C07D 413/12 20060101
C07D413/12; C07D 401/12 20060101 C07D401/12; A61K 31/445 20060101
A61K031/445; A61K 31/454 20060101 A61K031/454; A61K 31/495 20060101
A61K031/495; A61K 31/496 20060101 A61K031/496; A61K 31/472 20060101
A61K031/472; A61K 31/506 20060101 A61K031/506; A61P 31/04 20060101
A61P031/04 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 10, 1999 |
GB |
9918869.0 |
Nov 16, 1999 |
GB |
9927093.6 |
Claims
1-20. (canceled)
21. A compound of formula (II), or a pharmaceutically or
veterinarily acceptable salt, hydrate or solvate thereof:
##STR00131## wherein Q represents a radical of formula
--N(OH)C(.dbd.O)H or formula --C(.dbd.O)NH(OH); R.sub.1 is
hydrogen; R.sub.2 is n-propyl, n-butyl, n-pentyl, benzyl or
cyclopentylmethyl, cyclopentylethyl, cyclohexylmethyl, or
cyclohexylethyl; A represents a group of formula (IIA) or (IIB)
##STR00132## wherein R.sub.4 is tert-butyl, isobutyl, benzyl or
methyl; and R.sub.5 and R.sub.6 taken together with the nitrogen
atom to which they are attached form a saturated heterocyclic first
ring of 5 to 7 atoms OTHER THAN a piperidine-1-yl or piperazin-4-yl
ring which is substituted by a substituent of formula --CH.sub.2Z,
--OZ, or --C(.dbd.O)Z wherein Z is a phenyl, 3,4
methylenedioxyphenyl, morpholinyl, pyrimidinyl, 1,2,3-thiadiazolyl,
1,4-thiazolyl, benzofuranyl, furanyl, thienyl, pyranyl, purrolyl,
pyrazolyl, isozazolyl, or pyridyl ring, which ring being optionally
be substituted by (C.sub.1-C.sub.6) alkyl, (C.sub.2-C.sub.6)
alkenyl, (C.sub.2-C.sub.6) alkynyl, phenyl or halophenyl,
monocyclic 5 or 6-membered heterocyclic, benzyl hydroxy, phenoxy,
or (C-C.sub.6) alkoxy, mercapto, or (C.sub.1-C.sub.6) alkylthio,
oxo, nitro, --COOH, or --COOR.sup.A, --CONH.sub.2, --CONHR.sup.A or
--CONR.sup.AR.sup.B, --COR.sup.A, --NHCOR.sup.A, --NH.sub.2,
--NHR.sup.A, --NR.sup.AR.sup.B, wherein R.sup.A and R.sup.B are
independently a (C.sub.1-C.sub.6) alkyl group.
22. A pharmaceutical or veterinary composition comprising a
compound as claimed in claim 1, together with a pharmaceutically or
veterinarily acceptable carrier.
23. A method of treatment of bacterial infections in humans and
non-human mammals, which comprises administering to a subject
suffering such infection an antibacterially effective amount of a
compound as claimed in claim 1.
Description
[0001] This invention relates to novel hydroxamic acid and N-formyl
hydroxylamine derivatives having antibacterial activity, to methods
of treatment using such compounds, and to pharmaceutical and
veterinary compositions comprising such compounds.
BACKGROUND TO THE INVENTION
[0002] Many classes of antibacterial agents are known, including
the penicillins and cephalosporins, tetracyclines, sulfonamides,
monobactams, fluoroquinolones and quinolones, aminoglycosides,
glycopeptides, macrolides, polymyxins, lincosamides, trimethoprim
and chloramphenicol. The fundamental mechanisms of action of these
antibacterial classes vary.
[0003] Bacterial resistance to many known antibacterials is a
growing problem. Accordingly there is a continuing need in the art
for alternative antibacterial agents, especially those which have
mechanisms of action fundamentally different from the known
classes.
[0004] Amongst the Gram-positive pathogens, such as Staphylococci,
Streptococci, Mycobacteria and Enterococci, resistant strains have
evolved/arisen which makes them particularly difficult to
eradicate. Examples of such strains are methicillin resistant
Staphylococcus aureus (MRSA), methicillin resistant coagulase
negative Staphylococci (MRCNS), penicillin resistant Streptococcus
pneumoniae and multiply resistant Enterococcus faecium.
[0005] Pathogenic bacteria are often resistant to the
aminoglycoside, .beta.-lactam (penicillins and cephalosporins), and
chloramphenicol types of antibiotic. This resistance involves the
enzymatic inactivation of the antibiotic by hydrolysis or by
formation of inactive derivatives. The .beta.-lactam (penicillin
and cephalosporin) family of antibiotics are characterised by the
presence of a .beta.-lactam ring structure. Resistance to this
family of antibiotics in clinical isolates is most commonly due to
the production of a "penicillinase" (.beta.-lactamase) enzyme by
the resistant bacterium which hydrolyses the .beta.-lactam ring
thus eliminating its antibacterial activity.
[0006] Recently there has been an emergence of vancomycin-resistant
strains of enterococci (Woodford N. 1998 Glycopeptide-resistant
enterococci: a decade of experience. Journal of Medical
Microbiology. 47(10):849-62). Vancomycin-resistant enterococci are
particularly hazardous in that they are frequent causes of hospital
based infections and are inherently resistant to most antibiotics.
Vancomycin works by binding to the terminal D-Ala-D-Ala residues of
the cell wall peptidioglycan precursor. The high-level resistance
to vancomycin is known as VanA and is conferred by a genes located
on a transposable element which alter the terminal residues to
D-Ala-D-lac thus reducing the affinity for vancomycin.
[0007] In view of the rapid emergence of multidrug-resistant
bacteria, the development of antibacterial agents with novel modes
of action that are effective against the growing number of
resistant bacteria, particularly the vancomycin resistant
enterococci and .beta.-lactam antibiotic-resistant bacteria, such
as methicillin-resistant Staphylococcus aureus, is of utmost
importance.
BRIEF DESCRIPTION OF THE INVENTION
[0008] This invention is based on the finding that certain
hydroxamic acid and N-formyl hydroxylamine derivatives have
antibacterial activity, and makes available a new group of
antibacterial agents. It has been found that the compounds with
which this invention is concerned are antibacterial with respect to
a range of bacteria, with potency against Gram-positive organisms
generally being greater than against Gram-negatives. Many of the
compounds of the invention show activity against bacteria
responsible for respiratory infections, such as Streptococcus
pneumoniae and Haemophilus influenzae.
[0009] Although it may be of interest to establish the mechanism of
action of the compounds with which the invention is concerned, it
is their ability to inhibit bacterial growth that makes them
useful. However, it is presently believed that their antibacterial
activity is due, at least in part, to intracellular inhibition of
bacterial polypeptide deformylase (PDF; EC 3.5.1.31).
[0010] All ribosome-mediated synthesis of proteins starts with a
methionine residue. In prokaryotes the methionyl moiety carried by
the initiator tRNA is N-formylated prior to its incorporation into
a polypeptide. Consequently, N-formylmethionine is always present
at the N-terminus of a nascent bacterial polypeptide. However, most
mature proteins do not retain the N-formyl group or the terminal
methionine residue. Deformylation is required prior to methionine
removal, since methionine aminopeptidase does not recognise
peptides with an N-terminal formylmethionine residue (Solbiati et
al., J. Mol. Biol. 290:607-614, 1999). Deformylation is, therefore,
a crucial step in bacterial protein biosynthesis and the enzyme
responsible, PDF, is essential for normal bacterial growth.
Although the gene encoding PDF (def) is present in all pathogenic
bacteria for which sequences are known (Meinnel et al., J. Mol.
Biol, 266:939-49, 1997), it has no eukaryotic counterpart, making
it an attractive target for antibacterial chemotherapy.
[0011] The isolation and characterisation of PDF has been
facilitated by an understanding of the importance of the metal ion
in the active site (Groche et al., Biophys. Biochem. Res. Commun.,
246:324-6, 1998). The Fe.sup.2+ form is highly active in vivo but
is unstable when isolated due to oxidative degradation (Rajagopalan
et al., J. Biol. Chem. 273:22305-10, 1998). The Ni.sup.2+ form of
the enzyme has specific activity comparable with the ferrous enzyme
but is oxygen-insensitive (Ragusa et al., J. Mol. Biol. 1998,
280:515-23, 1998). The Zn.sup.2+ enzyme is also stable but is
almost devoid of catalytic activity (Rajagopalan et al., J. Am.
Chem. Soc. 119:12418-12419, 1997).
[0012] Several X-ray crystal structures and NMR structures of E.
coli PDF, with or without bound inhibitors, have been published
(Chan et al., Biochemistry 36:13904-9, 1997; Becker et al., Nature
Struct. Biol. 5:1053-8, 1998; Becker et al., J. Biol. Chem.
273:11413-6, 1998; Hao et al., Biochemistry, 38:4712-9, 1999;
Dardel et al., J. Mol. Biol. 280:501-13, 1998; O'Connell et al., J.
Biomol. NMR, 13:311-24, 1999), indicating similarities in active
site geometry to metalloproteinases such as thermolysin and the
metzincins.
[0013] Recently the substrate specificity of PDF has been
extensively studied (Ragusa et al., J. Mot Biol. 289:1445-57, 1999;
Hu et al., Biochemistry 38:643-50, 1999; Meinnel et al.,
Biochemistry, 38:4287-95, 1999). These authors conclude that an
unbranched hydrophobic chain is preferred at P1', while a wide
variety of P2' substituents are acceptable and an aromatic
substituent may be advantageous at the P3' position. There have
also been reports that small peptidic compounds containing an
H-phosphonate (Hu et al., Bioorg. Med. Chem. Lett., 8:2479-82,
1998) or thiol (Meinnel et al., Biochemistry, 38:4287-95, 1999)
metal binding group are micromolar inhibitors of PDF. Peptide
aldehydes such as calpeptin (N-Cbz-Leu-norleucinal) have also been
shown to inhibit PDF (Durand et al., Arch. Biochem. Biophys.,
367:297-302, 1999). However, the identity of the metal binding
group and its spacing from the rest of the molecule ("recognition
fragment") has not been studied extensively. Furthermore,
non-peptidic PDF inhibitors, which may be desirable from the point
of view of bacterial cell wall permeability or oral bioavailability
in the host species, have not been identified.
RELATED PRIOR ART
[0014] Certain N-formyl hydroxylamine derivatives have previously
been claimed in the patent publications listed below, although very
few examples of such compounds have been specifically made and
described:
TABLE-US-00001 EP-B-0236872 (Roche) WO 92/09563 (Glycomed) WO
92/04735 (Syntex) WO 95/19965 (Glycomed) WO 95/22966 (Sanofi
Winthrop) WO 95/33709 (Roche) WO 96/23791 (Syntex) WO 96/16027
(Syntex/Agouron) WO 97/03783 (British Biotech) WO 97/18207 (DuPont
Merck) WO 98/38179 (GlaxoWellcome) WO 98/47863 (Labs Jaques
Logeais)
[0015] The pharmaceutical utility ascribed to the N-formyl
hydroxylamine derivatives in those publications is the ability to
inhibit matrix metalloproteinases (MMPs) and in some cases release
of tumour necrosis factor (TNF), and hence the treatment of
diseases or conditions mediated by those enzymes, such as cancer
and rheumatoid arthritis.
[0016] In addition to these, U.S. Pat. No. 4,738,803 (Rogues et
al.) also discloses N-formyl hydroxylamine derivatives, however,
these compounds are disclosed as enkephalinase inhibitors and are
proposed for use as antidepressants and hypotensive agents. Also,
WO 97/38705 (Bristol-Myers Squibb) discloses certain N-formyl
hydroxylamine derivatives as enkephalinase and angiotensin
converting enzyme inhibitors.
[0017] Our copending International Patent Application No. WO
99/39704 describes and claims, inter alia, the use of a compound of
formula (I) or a pharmaceutically or veterinarily acceptable salt
thereof in the preparation of an antibacterial composition:
##STR00001##
wherein R.sub.1 represents hydrogen, C.sub.1-C.sub.6 alkyl or
C.sub.1-C.sub.6 alkyl substituted by one or more halogen atoms;
R.sub.2 represents a substituted or unsubstituted C.sub.1-C.sub.6
alkyl, cycloalkyl(C.sub.1-C.sub.6 alkyl)- or aryl(C.sub.1-C.sub.6
alkyl)-group; and A represents a group of formula (IA), or
(IB):
##STR00002##
wherein R.sub.4 represents the side chain of a natural or
non-natural alpha amino acid, and R.sub.5 and R.sub.6 when taken
together with the nitrogen atom to which they are attached form an
optionally substituted saturated heterocyclic ring of 3 to 8 atoms
which ring is optionally fused to a carbocyclic or second
heterocyclic ring.
[0018] Very many hydroxamic acid derivatives are known. Many have
been disclosed as having matrix metalloproteinase (MMP) inhibitory
activity, and thus to be potentially useful for the treatment of
diseases mediated by MMPs, for example cancer, arthritides, and
conditions involving tissue remodeling such as wound healing, and
restenosis. In addition our International Patent Application No. WO
99/59568 describes the use of analogues of the
N-formylhydroxylamine derivatives of WO 99/39704 (wherein the
N-formylhydroxylamine group is replaced by a hydroxamic acid group)
in the preparation of an antibacterial composition.
BRIEF DESCRIPTION OF THE INVENTION
[0019] This invention relates to a group of antibacterially active
hydroxamic acid and N-formyl hydroxylamine compounds which differ
in structure from those of International Patent Applications Nos.
WO 99/59568 and WO 99/39704, principally in the nature of the
--NR.sub.5R.sub.6 group (see formulae (I), (IA) and (IB) above and
the hydroxamic acid analogues thereof). In those applications, the
term "optionally substituted" as used in relation to the saturated
heterocyclic ring formed by R.sub.5, R.sub.6 and the nitrogen to
which they are attached is defined as meaning certain specific
substituents. In the present compounds, the group --NR.sub.5R.sub.6
is also an optionally substituted saturated heterocyclic ring of 3
to 8 atoms which ring is optionally fused to a carbocyclic or
second heterocyclic ring, but the substituents are different from
those permitted by WO 99/59568 and WO 99/39704. The group
--NR.sub.5R.sub.6 of the N-formyl hydroxylamines and hydroxamic
acids of the invention is also believed to distinguish the present
compounds from those known in the MMP, TNF, ACE, and enkephalinase
inhibitor art.
DETAILED DESCRIPTION OF THE INVENTION
[0020] The present invention provides a compound of formula (II),
or a pharmaceutically or veterinarily acceptable salt, hydrate or
solvate thereof
##STR00003##
wherein Q represents a radical of formula --N(OH)CH(.dbd.O) or
formula --C(.dbd.O)NH(OH); R.sub.1 represents hydrogen,
C.sub.1-C.sub.6 alkyl or C.sub.1-C.sub.6 alkyl substituted by one
or more halogen atoms, or, except when Q is a radical of formula
--N(OH)CH(.dbd.O), a hydroxy, C.sub.1-C.sub.6 alkoxy,
C.sub.1-C.sub.6 alkenyloxy, amino, C.sub.1-C.sub.6 alkylamino, or
di-(C.sub.1-C.sub.6 alkyl)amino group; R.sub.2 represents a
substituted or unsubstituted C.sub.1-C.sub.6 alkyl,
cycloalkyl(C.sub.1-C.sub.6 alkyl)- or aryl(C.sub.1-C.sub.6
alkyl)-group; and A represents a group of formula (IIA), or
(IIB):
##STR00004##
wherein R.sub.4 represents the side chain of a natural or
non-natural alpha amino acid, and R.sub.5 and R.sub.6 when taken
together with the nitrogen atom to which they are attached form a
saturated heterocyclic first ring of 5 to 7 atoms which is
optionally fused to a saturated or unsaturated carbocyclic or
heterocyclic second ring of 5 to 7 atoms; characterised in that (a)
the said second ring is substituted by (C.sub.1-C.sub.6)alkyl,
(C.sub.2-C.sub.6)alkenyl, (C.sub.2-C.sub.6)alkynyl,
(C.sub.1-C.sub.6)alkoxy, hydroxy, mercapto,
(C.sub.1-C.sub.6)alkylthio, halo, amino, trifluoromethyl, oxo,
nitro, --COON, --CONH.sub.2, --COR.sup.A, --COOR.sup.A,
--NHCOR.sup.A, --CONHR.sup.A, --NHR.sup.A, --NR.sup.AR.sup.B, or
--CONR.sup.AR.sup.B wherein R.sup.A and R.sup.B are independently a
(C.sub.1-C.sub.6)alkyl group; and/or (b) the said first or second
ring is substituted by a group of formula (IIC), provided that the
first ring is not substituted by phenoxy, benzyl or benzyl
substituted by (C.sub.1-C.sub.6)alkyl, (C.sub.1-C.sub.6)alkoxy,
phenoxy, hydroxy, mercapto, (C.sub.1-C.sub.6)alkylthio, amino,
halo, trifluoromethyl, nitro, --COON, --CONH.sub.2, --COR.sup.A,
--COOR.sup.A, --NHCOR.sup.A, --CONHR.sup.A, --NHR.sup.A,
--NR.sup.AR.sup.B, or --CONR.sup.AR.sup.B wherein R.sup.A and
R.sup.B are independently a (C.sub.1-C.sub.6)alkyl group,
##STR00005##
wherein m, p and n are independently 0 or 1; Z represents, a
hydroxy group, or a phenyl or heterocyclic ring of 5 to 7 atoms
which is optionally fused to a saturated or unsaturated carbocyclic
or heterocyclic second ring of 5 to 7 atoms Alk.sup.1 and Alk.sup.2
independently represent divalent C.sub.1-C.sub.3 alkylene radicals;
X represents --O--, --S--, --S(O)--, --S(O.sub.2)--, --C(.dbd.O)--,
--NH--, --NR.sub.7-- where R.sub.7 is C.sub.1-C.sub.3 alkyl; and
wherein Alk.sup.1, Alk.sup.2 and Z when Z is not a hydroxy group
independently are optionally substituted by [0021]
(C.sub.1-C.sub.6)alkyl, (C.sub.2-C.sub.6)alkenyl, or
(C.sub.2-C.sub.6)alkynyl, [0022] phenyl, or halophenyl, [0023]
trifluoromethyl, [0024] monocyclic 5 or 6-membered hetrocyclic,
[0025] benzyl, or halophenylmethyl, [0026] hydroxy, phenoxy,
(C.sub.1-C.sub.6)alkoxy, or hydroxy(C.sub.1-C.sub.6)alkyl, [0027]
mercapto, (C.sub.1-C.sub.6)alkylthio or mercapto
(C.sub.1-C.sub.6)alkyl, [0028] oxo, [0029] nitro, [0030] cyano
(--CN) [0031] halo (bromo, chloro, fluoro, or iodo) [0032] --COON,
or --COOR.sup.A, [0033] --CONH.sub.2--CONHR.sup.A, or
--CONR.sup.AR.sup.B [0034] --COR.sup.A, --SO.sub.2R.sup.A, [0035]
--NHCOR.sup.A, [0036] --NH.sub.2, --NHR.sup.A, or
--NR.sup.AR.sup.B, [0037] wherein R.sup.A and R.sup.B are
independently a (C.sub.1-C.sub.6) alkyl group, R.sup.A and R.sup.B
taken together with the nitrogen atom to which they are attached
form a 5- or 6-membered heterocyclic ring which may be substituted
by (C.sub.1-C.sub.3)alkyl, hydroxy, or
hydroxy(C.sub.1-C.sub.3)alkyl.
[0038] A subset of compounds of the invention consists of those of
formula (II) as defined above wherein:
(a) the said second ring is substituted by (C.sub.1-C.sub.6)alkyl,
(C.sub.2-C.sub.6)alkenyl, (C.sub.2-C.sub.6)alkynyl,
(C.sub.1-C.sub.6)alkoxy, hydroxy, mercapto,
(C.sub.1-C.sub.6)alkylthio, amino, trifluoromethyl, oxo, nitro,
--COON, --CONH.sub.2, --COR.sup.A, --COOR.sup.A, --NHCOR.sup.A,
--CONHR.sup.A, --NHR.sup.A, --NR.sup.AR.sup.B, or
--CONR.sup.AR.sup.B wherein R.sup.A and R.sup.B are independently a
(C.sub.1-C.sub.6)alkyl group; and/or (b) the said first or second
ring is substituted by a group of formula (IIC), provided that the
first ring is not substituted by phenoxy, benzyl or benzyl
substituted by (C.sub.1-C.sub.6)alkyl, (C.sub.1-C.sub.6)alkoxy,
phenoxy, hydroxy, mercapto, (C.sub.1-C.sub.6)alkylthio, amino,
halo, trifluoromethyl, nitro, --COON, --CONH.sub.2--COR.sup.A,
--COOR.sup.A, --NHCOR.sup.A, --CONHR.sup.A, --NHR.sup.A,
--NR.sup.AR.sup.B, or --CONR.sup.AR.sup.B wherein R.sup.A and
R.sup.B are independently a (C.sub.1-C.sub.6)alkyl group,
##STR00006##
wherein m, p and n are independently 0 or 1; Z represents, a
hydroxy group, or a phenyl or heterocyclic ring of 5 to 7 atoms
which is optionally fused to a saturated or unsaturated carbocyclic
or heterocyclic second ring of 5 to 7 atoms Alk.sup.1 and Alk.sup.2
independently represent divalent C.sub.1-C.sub.3 alkylene radicals;
X represents --O--, --S--, --S(O)--, --S(O.sub.2)--, --C(.dbd.O)--,
--NH--, --NR.sub.7-- where R.sub.7 is C.sub.1-C.sub.3 alkyl; and
wherein Alk.sup.1, Alk.sup.2 and Z when Z is not a hydroxy group
independently are optionally substituted by [0039]
(C.sub.1-C.sub.6)alkyl, (C.sub.2-C.sub.6)alkenyl, or
(C.sub.2-C.sub.6)alkynyl, [0040] phenyl, or halophenyl, [0041]
trifluoromethyl, [0042] monocyclic 5 or 6-membered hetrocyclic,
[0043] benzyl, [0044] hydroxy, phenoxy, or (C.sub.1-C.sub.6)alkoxy,
[0045] mercapto, or (C.sub.1-C.sub.6)alkylthio, [0046] oxo, [0047]
nitro, [0048] --COON, or --COOR.sup.A, [0049] --CONH.sub.2,
--CONHR.sup.A, or --CONR.sup.AR.sup.B [0050] --COR.sup.A, [0051]
--NHCOR.sup.A, [0052] --NH.sub.2, --NHR.sup.A, or
--NR.sup.AR.sup.B, [0053] wherein R.sup.A and R.sup.B are
independently a (C.sub.1-C.sub.6) alkyl group,
[0054] In another aspect, the invention provides a method for the
treatment of bacterial infections in humans and non-human mammals,
which comprises administering to a subject suffering such infection
an antibacterially effective dose of a compound of formula (II) as
defined above.
[0055] In a further aspect of the invention there is provided a
method for the treatment of bacterial contamination by applying an
antibacterially effective amount of a compound of formula (II) as
defined above to the site of contamination.
[0056] The compounds of formula (II) as defined above may be used
as component(s) of antibacterial cleaning or disinfecting
materials.
[0057] On the hypothesis that the compounds (II) act by inhibition
of intracellular PDF, the most potent antibacterial effect may be
achieved by using compounds which efficiently pass through the
bacterial cell wall. Thus, compounds which are highly active as
inhibitors of PDF in vitro and which penetrate bacterial cells are
preferred for use in accordance with the invention. It is to be
expected that the antibacterial potency of compounds which are
potent inhibitors of the PDF enzyme in vitro, but are poorly cell
penetrant, may be improved by their use in the form of a prodrug,
ie a structurally modified analogue which is converted to the
parent molecule of formula (II), for example by enzymic action,
after it has passed through the bacterial cell wall.
[0058] As used herein the term "(C.sub.1-C.sub.6)alkyl" means a
straight or branched chain alkyl moiety having from 1 to 6 carbon
atoms, including for example, methyl, ethyl, n-propyl, isopropyl,
n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl and n-hexyl.
[0059] As used herein the term "divalent (C.sub.1-C.sub.3)alkylene
radical" means a saturated hydrocarbon chain having from 1 to 3
carbon atoms and two unsatisfied valencies.
[0060] As used herein the term "(C.sub.2-C.sub.6)alkenyl" means a
straight or branched chain alkenyl moiety having from 2 to 6 carbon
atoms having at least one double bond of either E or Z
stereochemistry where applicable. The term includes, for example,
vinyl, allyl, 1- and 2-butenyl and 2-methyl-2-propenyl.
[0061] As used herein the term "C.sub.2-C.sub.6 alkynyl" refers to
straight chain or branched chain hydrocarbon groups having from two
to six carbon atoms and having in addition one triple bond. This
term would include for example, ethynyl, 1-propynyl, 1- and
2-butynyl, 2-methyl-2-propynyl, 2-pentynyl, 3-pentynyl, 4-pentynyl,
2-hexynyl, 3-hexynyl, 4-hexynyl and 5-hexynyl.
[0062] As used herein the term "cycloalkyl" means a saturated
alicyclic moiety having from 3-8 carbon atoms and includes, for
example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl,
cycloheptyl and cyclooctyl.
[0063] As used herein the term "heteroaryl" refers to a 5- or
6-membered aromatic ring containing one or more heteroatoms.
Illustrative of such groups are thienyl, furyl, pyrrolyl,
imidazolyl, benzimidazolyl, thiazolyl, pyrazolyl, isoxazolyl,
isothiazolyl, triazolyl, thiadiazolyl, oxadiazolyl, pyridinyl,
pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl.
[0064] As used herein the unqualified term "heterocyclyl" or
"heterocyclic" includes "heteroaryl" as defined above, and in
particular means a 5-7 membered aromatic or non-aromatic
heterocyclic ring containing one or more heteroatoms selected from
S, N and O, including for example, pyrrolyl, furanyl, thienyl,
piperidinyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl,
thiadiazolyl, pyrazolyl, pyridinyl, pyrrolidinyl, pyrimidinyl,
morpholinyl, piperazinyl, indolyl, morpholinyl, benzofuranyl,
pyranyl, isoxazolyl, benzimidazolyl, methylenedioxyphenyl,
maleimido and succinimido groups.
[0065] Unless otherwise specified in the context in which it
occurs, the term "substituted" as applied to any moiety herein
means substituted with up to four substituents, each of which
independently may be (C.sub.1-C.sub.6)alkyl,
(C.sub.1-C.sub.6)alkoxy, hydroxy, mercapto,
(C.sub.1-C.sub.6)alkylthio, amino, halo (including fluoro, chloro,
bromo and iodo), trifluoromethyl, nitro, --COON, --CONH.sub.2,
--COR.sup.A, --COOR.sup.A, --NHCOR.sup.A, --CONHR.sup.A,
--NHR.sup.A, --NR.sup.AR.sup.B, or --CONR.sup.AR.sup.B wherein
R.sup.A and R.sup.B are independently a (C.sub.1-C.sub.6)alkyl
group
[0066] As used herein the terms "side chain of a natural
alpha-amino acid" and "side chain of a non-natural alpha-amino
acid" mean the group R.sup.x in respectively a natural and
non-natural amino acid of formula NH.sub.2--CH(R.sup.x)--COOH.
[0067] Examples of side chains of natural alpha amino acids include
those of alanine, arginine, asparagine, aspartic acid, cysteine,
cystine, glutamic acid, histidine, 5-hydroxylysine,
4-hydroxyproline, isoleucine, leucine, lysine, methionine,
phenylalanine, proline, serine, threonine, tryptophan, tyrosine,
valine, .alpha.-aminoadipic acid, .alpha.-amino-n-butyric acid,
3,4-dihydroxyphenylalanine, homoserine, .alpha.-methylserine,
ornithine, pipecolic acid, and thyroxine.
[0068] In natural alpha-amino acid side chains which contain
functional substituents, for example amino, carboxyl, hydroxy,
mercapto, guanidyl, imidazolyl, or indolyl groups as in arginine,
lysine, glutamic acid, aspartic acid, tryptophan, histidine,
serine, threonine, tyrosine, and cysteine, such functional
substituents may optionally be protected.
[0069] Likewise, in the side chains of non-natural alpha amino
acids which contain functional substituents, for example amino,
carboxyl, hydroxy, mercapto, guanidyl, imidazolyl, or indolyl
groups, such functional substituents may optionally be
protected.
[0070] The term "protected" when used in relation to a functional
substituent in a side chain of a natural or non-natural alpha-amino
acid means a derivative of such a substituent which is
substantially non-functional. The widely used handbook by T. W.
Greene and P. G. Wuts "Protective Groups in Organic Synthesis"
Second Edition, Wiley, New York, 1991 reviews the subject. For
example, carboxyl groups may be esterified (for example as a
C.sub.1-C.sub.6 alkyl ester), amino groups may be converted to
amides (for example as a NHCOC.sub.1-C.sub.6 alkyl amide) or
carbamates (for example as an NHC(.dbd.O)OC.sub.1-C.sub.6 alkyl or
NHC(.dbd.O)OCH.sub.2Ph carbamate), hydroxyl groups may be converted
to ethers (for example an OC.sub.1-C.sub.6 alkyl or a
O(C.sub.1-C.sub.6 alkyl)phenyl ether) or esters (for example a
OC(.dbd.O)C.sub.1-C.sub.6 alkyl ester) and thiol groups may be
converted to thioethers (for example a tert-butyl or benzyl
thioether) or thioesters (for example a SC(.dbd.O)C.sub.1-C.sub.6
alkyl thioester).
[0071] There are several actual or potential chiral centres in the
compounds according to the invention because of the presence of
asymmetric carbon atoms. The presence of several asymmetric carbon
atoms gives rise to a number of diastereoisomers with R or S
stereochemistry at each chiral centre. The invention includes all
such diastereoisomers and mixtures thereof. Currently, the
preferred stereoconfiguration of the carbon atom carrying the
R.sub.2 group is R; that of the carbon atom carrying the R.sub.4
group (when asymmetric) is S; and that of the carbon atom carrying
the R.sub.1, group (when asymmetric) is R.
[0072] In the compounds of the invention:
[0073] R.sub.1 may be, for example, hydrogen, methyl, or
trifluoromethyl. Hydrogen is currently preferred.
[0074] R.sub.2 may be, for example: [0075] optionally substituted
C.sub.1-C.sub.8 alkyl, C.sub.3-C.sub.6 alkenyl, C.sub.3-C.sub.6
alkynyl or cycloalkyl; [0076] phenyl(C.sub.1-C.sub.6 alkyl)-,
phenyl(C.sub.3-C.sub.6 alkenyl)- or phenyl(C.sub.3-C.sub.6
alkynyl)- optionally substituted in the phenyl ring; [0077]
cycloalkyl(C.sub.1-C.sub.6 alkyl)-, cycloalkyl(C.sub.3-C.sub.6
alkenyl)- or cycloalkyl(C.sub.3-C.sub.6 alkynyl)- optionally
substituted in the cycloalkyl ring; [0078]
heterocyclyl(C.sub.1-C.sub.6 alkyl)-, heterocyclyl(C.sub.3-C.sub.6
alkenyl)- or heterocyclyl(C.sub.3-C.sub.6 alkynyl)- optionally
substituted in the heterocyclyl ring; or [0079]
CH.sub.3(CH.sub.2).sub.pO(CH.sub.2).sub.q or
CH.sub.3(CH.sub.2).sub.pS(CH.sub.2).sub.q--, wherein p is 0, 1, 2
or 3 and q is 1, 2 or 3.
[0080] Specific examples of R.sub.2 groups include [0081] methyl,
ethyl, n- and iso-propyl, n- and iso-butyl, n-pentyl, iso-pentyl
3-methyl-but-1-yl, n-hexyl, n-heptyl, n-acetyl, n-octyl,
methylsulfanylethyl, ethylsulfanylmethyl, 2-methoxyethyl,
2-ethoxyethyl, 2-ethoxymethyl, 3-hydroxypropyl, allyl,
3-phenylprop-3-en-1-yl, 3-phenylprop-2-yn-1-yl,
3-(2-chlorophenyl)prop-2-yn-1-yl, but-2-yn-1-yl, cyclopentyl,
cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylpropyl,
cyclohexylmethyl, cyclohexylethyl, cyclohexylpropyl,
furan-2-ylmethyl, furan-3-methyl, tetrahydrofuran-2-ylmethyl,
tetrahydrofuran-2-ylmethyl, piperidinylmethyl, phenylpropyl,
4-chlorophenylpropyl, 4-methylphenylpropyl, 4-methoxyphenylpropyl,
benzyl, 4-chlorobenzyl, 4-methylbenzyl, and 4-methoxybenzyl. [0082]
Presently preferred groups at R.sub.2 are (C.sub.1-C.sub.6)alkyl-,
cycloalkylmethyl-,
(C.sub.1-C.sub.3)alkyl-S--(C.sub.1-C.sub.3)alkyl-, or
(C.sub.1-C.sub.3)alkyl-O--(C.sub.1-C.sub.3)alkyl-, especially
n-propyl, n-butyl, n-pentyl, cyclopentylmethyl, cyclopentylethyl,
cyclohexylmethyl or cyclohexylethyl.
[0083] R.sub.4 may be, for example [0084] the characterising group
of a natural a amino acid, for example benzyl, or
4-methoxyphenylmethyl, in which any functional group may be
protected, any amino group may be acylated and any carboxyl group
present may be amidated; or [0085] a group--[Alk].sub.nR.sub.9
where Alk is a (C.sub.1-C.sub.6)alkylene or
(C.sub.2-C.sub.6)alkenylene group optionally interrupted by one or
more --O--, or --S-- atoms or --N(R.sub.12)-- groups [where
R.sub.12 is a hydrogen atom or a (C.sub.1-C.sub.6)alkyl group], n
is 0 or 1, and R.sub.9 is hydrogen or an optionally substituted
phenyl, aryl, heterocyclyl, cycloalkyl or cycloalkenyl group or
(only when n is 1) R.sub.9 may additionally be hydroxy, mercapto,
(C.sub.1-C.sub.6)alkylthio, amino, halo, trifluoromethyl, nitro,
--COOH, --CONH.sub.2, --COOR.sup.A, --NHCOR.sup.A, --CONHR.sup.A,
--NHR.sup.A, NR.sup.AR.sup.B, or --CONR.sup.AR.sup.B wherein
R.sup.A and R.sup.B are independently a (C.sub.1-C.sub.6)alkyl
group; or [0086] a benzyl group substituted in the phenyl ring by a
group of formula --OCH.sub.2COR.sub.8 where R.sub.8 is hydroxyl,
amino, (C.sub.1-C.sub.6)alkoxy, phenyl(C.sub.1-C.sub.6)alkoxy,
(C.sub.1-C.sub.6)alkylamino, di((C.sub.1-C.sub.6)alkyl)amino,
phenyl(C.sub.1-C.sub.6)alkylamino; or [0087] a heterocyclic
(C.sub.1-C.sub.6)alkyl group, either being unsubstituted or mono-
or di-substituted in the heterocyclic ring with halo, nitro,
carboxy, (C.sub.1-C.sub.6)alkoxy, cyano, (C.sub.1-C.sub.6)alkanoyl,
trifluoromethyl (C.sub.1-C.sub.6)alkyl, hydroxy, formyl, amino,
(C.sub.1-C.sub.6)alkylamino, di-(C.sub.1-C.sub.6)alkylamino,
mercapto, (C.sub.1-C.sub.6)alkylthio,
hydroxy(C.sub.1-C.sub.6)alkyl, mercapto (C.sub.1-C.sub.6)alkyl or
(C.sub.1-C.sub.6)alkylphenylmethyl; or [0088] a group
--CR.sub.aR.sub.bR.sub.c in which: [0089] each of R.sub.a, R.sub.b
and R.sub.c is independently hydrogen, (C.sub.1-C.sub.6)alkyl,
(C.sub.2-C.sub.6)alkenyl, (C.sub.2-C.sub.6)alkynyl,
phenyl(C.sub.1-C.sub.6)alkyl, (C.sub.3-C.sub.8)cycloalkyl; or
[0090] R.sub.c is hydrogen and R.sub.a and R.sub.b are
independently phenyl or heteroaryl such as pyridyl; or [0091]
R.sub.c is hydrogen, (C.sub.1-C.sub.6)alkyl,
(C.sub.2-C.sub.6)alkenyl, (C.sub.2-C.sub.6)alkynyl,
phenyl(C.sub.1-C.sub.6)alkyl, or (C.sub.3-C.sub.6)cycloalkyl, and
R.sub.a and R.sub.b together with the carbon atom to which they are
attached form a 3 to 8 membered cycloalkyl or a 5- to 6-membered
heterocyclic ring; or [0092] R.sub.a, R.sub.b and R.sub.c together
with the carbon atom to which they are attached form a tricyclic
ring (for example adamantyl); or [0093] R.sub.a and R.sub.b are
each independently (C.sub.1-C.sub.6)alkyl,
(C.sub.2-C.sub.6)alkenyl, (C.sub.2-C.sub.6)alkynyl,
phenyl(C.sub.1-C.sub.6)alkyl, or a group as defined for R.sub.c
below other than hydrogen, or R.sub.a and R.sub.b together with the
carbon atom to which they are attached form a cycloalkyl or
heterocyclic ring, and R.sub.c is hydrogen, --OH, --SH, halogen,
--CN, --CO.sub.2H, (C.sub.1-C.sub.4)perfluoroalkyl, --CH.sub.2OH,
--CO.sub.2(C.sub.1-C.sub.6)alkyl, --O(C.sub.1-C.sub.6)alkyl,
--O(C.sub.2-C.sub.6)alkenyl, --S(C.sub.1-C.sub.6)alkyl,
--SO(C.sub.1-C.sub.6)alkyl, --SO.sub.2(C.sub.1-C.sub.6)alkyl,
--S(C.sub.2-C.sub.6)alkenyl, --SO(C.sub.2-C.sub.6)alkenyl,
--SO.sub.2(C.sub.2-C.sub.6)alkenyl or a group -Q-W wherein Q
represents a bond or --O--, --S--, --SO-- or --SO.sub.2-- and W
represents a phenyl, phenylalkyl, (C.sub.3-C.sub.8)cycloalkyl,
(C.sub.3-C.sub.6)cycloalkylalkyl, (C.sub.4-C.sub.6)cycloalkenyl,
(C.sub.4-C.sub.8)cycloalkenylalkyl, heteroaryl or heteroarylalkyl
group, which group W may optionally be substituted by one or more
substituents independently selected from, hydroxyl, halogen, --CN,
--CO.sub.2H, --CO.sub.2(C.sub.1-C.sub.6)alkyl, --CONH.sub.2,
--CONH(C.sub.1-C.sub.6)alkyl, --CONH(C.sub.1-C.sub.6alkyl).sub.2,
--CHO, --CH.sub.2OH, (C.sub.1-C.sub.4)perfluoroalkyl,
--O(C.sub.1-C.sub.6)alkyl, --S(C.sub.1-C.sub.6)alkyl,
--SO(C.sub.1-C.sub.6)alkyl, --SO.sub.2(C.sub.1-C.sub.6)alkyl,
--NO.sub.2, --NH.sub.2, --NH(C.sub.1-C.sub.6)alkyl,
--N((C.sub.1-C.sub.6)alkyl).sub.2, --NHCO(C.sub.1-C.sub.6)alkyl,
(C.sub.1-C.sub.6)alkyl, (C.sub.2-C.sub.6)alkenyl,
(C.sub.2-C.sub.6)alkynyl, (C.sub.3-C.sub.8)cycloalkyl,
(C.sub.4-C.sub.8)cycloalkenyl, phenyl or benzyl.
[0094] Examples of particular R.sub.4 groups include methyl, ethyl,
benzyl, 4-chlorobenzyl, 4-hydroxybenzyl, phenyl, cyclohexyl,
cyclohexylmethyl, pyridin-3-ylmethyl, tert-butoxymethyl,
naphthylmethyl, iso-butyl, sec-butyl, tert-butyl,
1-benzylthio-1-methylethyl, 1-methylthio-1-methylethyl,
1-mercapto-1-methylethyl, 1-methoxy-1-methylethyl,
1-hydroxy-1-methylethyl, 1-fluoro-1-methylethyl, hydroxymethyl,
2-hydroxethyl, 2-carboxyethyl, 2-methylcarbamoylethyl,
2-carbamoylethyl, and 4-aminobutyl. Presently preferred R.sub.4
groups include tert-butyl, iso-butyl, benzyl, isopropyl and
methyl.
[0095] R.sub.5 and R.sub.6 taken together with the nitrogen atom to
which they are attached form a saturated 5- to 7-membered
monocyclic N-heterocyclic first ring which is attached via the N
atom, and which is optionally fused to a saturated or unsaturated
carbocyclic or heterocyclic second ring of 5 to 7 atoms. One or
more additional ring hetero atoms such as nitrogen may be present
in the first ring. Examples of such first rings are 1-pyrrolidinyl,
piperidin-1-yl, 1-piperazinyl, hexahydro-1-pyridazinyl,
morpholin-4-yl, tetrahydro-1,4-thiazin-4-yl,
tetrahydro-1,4-thiazin-4-yl 1-oxide, tetrahydro-1,4-thiazin-4-yl
1,1-dioxide, hexahydroazipino, thiomorpholino, diazepino,
thiazolidinyl or octahydroazocino. Presently preferred are
piperidin-1-yl and 1-piperazinyl. The substituent (IIC) may be
present on a ring carbon atom or a ring nitrogen atom of the first
or second rings.
[0096] In the substituent (IIC) (from whose definition benzyl,
certain substituted benzyls, and phenoxy are excluded) Alk.sup.1
and Alk.sup.2 may independently represent, for example
--(CH.sub.2)-- or --(CH.sub.2CH.sub.2)--. In the case where m is 0
and p is 1, X may be, for example --C(.dbd.O)-- or --S(O.sub.2)--.
In such cases n may be 0 or 1, and when the --NR.sub.5R.sub.6 first
ring contains a second ring nitrogen, the --C(.dbd.O)-- or
--S(O.sub.2)-- of (IIC) may be linked to that ring nitrogen in an
amide or sulphonamide bond.
[0097] In the substituent (IIC) m, n and p may all be 0, so that
the group Z is directly linked to the --NR.sub.5R.sub.6 first
ring.
[0098] In a preferred subset of the compounds of the invention, the
substituent (IIC) has the formula --CH.sub.2Z, --OZ, or
--(C.dbd.O)Z wherein (subject to the exclusion of benzyl, certain
substituted benzyls, and phenoxy) Z is a phenyl,
3,4-methylenedioxyphenyl, morpholinyl, pyrimidinyl,
1,2,3-thiadiazolyl, 1,4-thiazolyl, benzofuranyl, furanyl, thienyl,
pyranyl, pyrrolyl, pyrazolyl, isoxazolyl, or pyridyl ring which may
optionally be substituted as specified. In particular, Z may be a
phenyl, 3,4-methylenedioxyphenyl, morpholinyl, pyrimidin-2-yl,
1,2,3-thiadiazol-5-yl, 1,4-thiazol-5-yl, benzofuran-2-yl, 2- or
3-furanyl, 2- or 3-thienyl, 2- or 3-pyranyl, 2-, 3- or 4-pyrrolyl,
3-, 4- or 5-pyazolyl, 3-, 4- or 5-isoxazolyl, or 2-, 3- or
4-pyridyl ring any of which may optionally be substituted as
specified in the broad description of the compounds of the
invention.
[0099] In the compounds of formula (II) as defined above wherein Q
is a radical of formula --C(.dbd.O)NH(OH) the radicals R.sub.1,
R.sub.2, and A may be any of those discussed above in relation to
compounds (II) wherein Q is a radical of formula --N(OH)CH(.dbd.O).
However, in addition, R.sub.1 may be, for example, a hydroxy,
methoxy, ethoxy, n-propyloxy, allyloxy, amino, methylamino,
dimethylamino, ethylamino, or diethylamino group.
[0100] Specific examples of substituents (IIC) include those
present in the compounds specifically named, and/or exemplified
herein.
[0101] Examples of specific compounds of the invention are those of
the Examples herein. In those Examples, where a compound of formula
(II) above wherein Q is an N-formylhydroxylamine radical
--N(OH)CH(.dbd.O) is disclosed, it is to be understood that the
equivalent compound wherein Q is a hydroxamate radical
--C(.dbd.O)NH(OH) is also a specific compound of the invention, and
vice versa.
[0102] Preferred compounds of the invention include those selected
from the group consisting of compounds of formulae (IID)-(IIG) and
(IIW)-(IIZ):
##STR00007##
wherein R.sub.2 is n-propyl, n-butyl, n-pentyl, cyclopentylmethyl,
cyclopentylethyl, cyclohexylmethyl or cyclohexylethyl; R.sub.4 is
tert-butyl, iso-butyl, benzyl or methyl;
Y is --CH.sub.2--, --O-- or --(C.dbd.O)--; and
[0103] Z is a phenyl, 3,4-methylenedioxyphenyl, morpholinyl,
pyrimidinyl, 1,2,3-thiadiazolyl, 1,4-thiazolyl, benzofuranyl,
furanyl, thienyl, pyranyl, pyrrolyl, pyrazolyl, isoxazolyl, or
pyridyl ring; in particular, a phenyl, 3,4-methylenedioxyphenyl,
morpholinyl, pyrimidin-2-yl, 1,2,3-thiadiazol-5-yl,
1,4-thiazol-5-yl, benzofuran-2-yl, 2- or 3-furanyl, 2- or
3-thienyl, 2- or 3-pyranyl, 2-, 3- or 4-pyrrolyl, 3-, 4- or
5-pyazolyl, 3-, 4- or 5-isoxazolyl, or 2-, 3- or 4-pyridyl ring,
which may optionally be substituted as specified in the general
description of compounds of the invention.
[0104] Particular compounds of the invention, preferred for their
potency against organisms which infect the respiratory system,
include
N-[1S-(4-benzo[1,3]dioxol-5-ylmethyl-piperazine-1-carbonyl)-2,2-dimethyl--
propyl]-2R-cyclopentylmethyl-3-(formyl-hydroxy-amino)-propionamide
and
N-[1S-(4-Benzo[1,3]dioxol-5-ylmethyl-piperazine-1-carbonyl)-2,2-dimethyl--
propyl]-2R-cyclopentylmethyl-N-hydroxy-succinamide
[0105] Compounds of the invention in which Q is an
N-formylhydroxyamino group may be prepared by deprotecting an
O-protected N-formyl-N-hydroxyamino compound of formula (III):
##STR00008##
in which R.sub.1, R.sub.2, and A are as defined in general formula
(I) and R.sub.25 is a hydroxy protecting group removable to leave a
hydroxy group by hydrogenolysis or hydrolysis. Benzyl is a
preferred R.sub.25 group for removal by hydrogenolysis, and
tert-butyl and tetrahydropyranyl are preferred groups for removal
by acid hydrolysis.
[0106] Compounds of the invention in which Q is a hydroxamic acid
group may be prepared by reacting the parent compound wherein Q is
a carboxylic acid group (IIIA)
##STR00009##
with hydroxylamine or an N- and/or O-protected hydroxylamine, and
thereafter removing any O- or N-protecting groups
[0107] Compounds of formula (III) or (IIIA) may be prepared by
causing an acid of formula (IV) or (IVC) or an activated derivative
thereof to react with an amine of formula (IVA) or (IVB)
##STR00010##
wherein R.sub.1, R.sub.2, R.sub.4, R.sub.5, and R.sub.6 are as
defined in general formula (II) except that any substituents in
R.sub.1, R.sub.2, R.sub.4, R.sub.5, and R.sub.6 which are
potentially reactive in the coupling reaction may themselves be
protected from such reaction, and R.sub.25 is as defined in
relation to formula (III) above, and optionally removing protecting
groups R.sub.1, R.sub.2, R.sub.4, R.sub.5, and R.sub.6.
[0108] Compounds of formula (IVA), (IVB) and (IVC) are prepared by
standard literature methods, and many are commercially
available.
[0109] Compounds of formula (IV) may be prepared by N-formylation,
for example using acetic anhydride and formic acid, or
1-formylbenzotriazole, of compounds of formula (V)
##STR00011##
wherein R.sub.1, R.sub.2 and R.sub.25 are as defined in relation to
formula (III) and Y is either a chiral auxiliary or an OR.sub.26
group wherein R.sub.26 is hydrogen or a hydroxy protecting group.
In the case where Y is an OR.sub.26 group or a chiral auxiliary the
hydroxy protecting group or auxiliary is removed after the
formylation step to provide the compound of formula (IV). Suitable
chiral auxiliaries include substituted oxazolidinones which may be
removed by hydrolysis in the presence of base.
[0110] A compound of general formula (V) may be prepared by
reduction of an oxime of general formula (VII)
##STR00012##
wherein R.sup.1, R.sub.2, and R.sub.25 are as defined above, and Y
is either an OR.sub.26 group as defined above or a chiral
auxiliary. Reducing agents include certain metal hydrides (eg
sodium cyanoborohydride in acetic acid, triethylsilane or
borane/pyridine) and hydrogen in the presence of a suitable
catalyst. Following the reduction when the group Y is a chiral
auxiliary it may be optionally converted to a OR.sub.26 group.
[0111] A compound of general formula (VII) can be prepared by
reaction of a .beta.-keto carbonyl compound of general formula
(VIII)
##STR00013##
wherein R.sup.1, R.sub.2, and Y are as defined above, with an
O-protected hydroxylamine.
[0112] .beta.-keto carbonyl compounds (VIII) may be prepared in
racemic form by formylation or acylation of a carbonyl compound of
general formula (IX)
##STR00014##
wherein R.sub.2 and Y are as defined above, with a compound of
general formula (X)
##STR00015##
wherein R.sub.1 is as defined above and Q is a leaving group such
as halogen or alkoxy, in the presence of a base.
[0113] The Examples herein provide further details of routes and
methods for the preparation of compounds of the invention.
[0114] Salts of the compounds of the invention include
physiologically acceptable acid addition salts for example
hydrochlorides, hydrobromides, sulphates, methane sulphonates,
p-toluenesulphonates, phosphates, acetates, citrates, succinates,
lactates, tartrates, fumarates and maleates. Salts may also be
formed with bases, for example sodium, potassium, magnesium, and
calcium salts.
[0115] Compositions with which the invention is concerned may be
prepared for administration by any route consistent with the
pharmacokinetic properties of the active ingredient(s).
[0116] Orally administrable compositions may be in the form of
tablets, capsules, powders, granules, lozenges, liquid or gel
preparations, such as oral, topical, or sterile parenteral
solutions or suspensions. Tablets and capsules for oral
administration may be in unit dose presentation form, and may
contain conventional excipients such as binding agents, for example
syrup, acacia, gelatin, sorbitol, tragacanth, or
polyvinyl-pyrrolidone; fillers for example lactose, sugar,
maize-starch, calcium phosphate, sorbitol or glycine; tabletting
lubricant, for example magnesium stearate, talc, polyethylene
glycol or silica; disintegrants for example potato starch, or
acceptable wetting agents such as sodium lauryl sulphate. The
tablets may be coated according to methods well known in normal
pharmaceutical practice. Oral liquid preparations may be in the
form of, for example, aqueous or oily suspensions, solutions,
emulsions, syrups or elixirs, or may be presented as a dry product
for reconstitution with water or other suitable vehicle before use.
Such liquid preparations may contain conventional additives such as
suspending agents, for example sorbitol, syrup, methyl cellulose,
glucose syrup, gelatin hydrogenated edible fats; emulsifying
agents, for example lecithin, sorbitan monooleate, or acacia;
non-aqueous vehicles (which may include edible oils), for example
almond oil, fractionated coconut oil, oily esters such as
glycerine, propylene glycol, or ethyl alcohol; preservatives, for
example methyl or propyl p-hydroxybenzoate or sorbic acid, and if
desired conventional flavouring or colouring agents.
[0117] Safe and effective dosages for different classes of patient
and for different disease states will be determined by clinical
trial as is required in the art. It will be understood that the
specific dose level for any particular patient will depend upon a
variety of factors including the activity of the specific compound
employed, the age, body weight, general health, sex, diet, time of
administration, route of administration, rate of excretion, drug
combination and the severity of the particular disease undergoing
therapy.
[0118] The following examples illustrate embodiments of the
invention. Note that the "Preparative Example A" does not describe
the preparation of a compound of the invention, but is included to
provide details of synthetic routes and methods for the preparation
of compounds of the invention
[0119] .sup.1H and .sup.13C NMR spectra were recorded using a
Bruker DPX 250 spectrometer at 250.1 and 62.9 MHz, respectively.
Mass spectra were obtained using a Perkin Elmer Sciex API 165
spectrometer using both positive and negative ionisation modes.
Infra-red spectra were recorded on a Perkin Elmer PE 1600 FTIR
spectrometer. Analytical HPLC was performed on a Beckman System
Gold, using Waters Nova Pak C18 column (150 mm, 3.9 mm) with 20 to
90% solvent B gradient (1 mL/min) as the mobile phase. [Solvent A:
0.05% TFA in 10% water 90% methanol; Solvent B: 0.05% TFA in 10%
methanol 90%], detection wavelength at 230 nm. Preparative HPLC was
performed on a Gilson autoprep instrument using a C18 Waters delta
prep-pak cartridge (15 .mu.m, 300 A, 25 mm, 10 mm) with 20 to 90%
solvent B gradient (6 ml/min) as the mobile phase. [Solvent A
water; Solvent B: methanol], UV detection was at 230 nm.
[0120] The following abbreviations have been used throughout:
[0121] DCM Dichloromethane [0122] DEAD
Diethyl-azo-dichlorocarboxylate [0123] EDC
N-Ethyl-N'-(3-dimethylaminopropyl)carbodiimide hydrochloride [0124]
HOAt 1-Hydroxy-7-aza-benzotriazole [0125] HOBt
1-Hydroxybenzotriazole [0126] HPLC High performance liquid
chromatography [0127] LRMS Low resolution mass spectrometry [0128]
NMR Nuclear magnetic resonance [0129] RT Retention Time [0130] TLC
Thin layer chromatography [0131] TFA Trifluoroacetic acid [0132]
THF Tetrahydrofuran
Example 1
2R-[(Formyl-hydroxy-amino)-methyl]hexanoic acid
{1S-[4-(4-methoxy-benzoyl)-piperidine-1-carbonyl]-2,2-dimethyl-propyl}-am-
ide
##STR00016##
[0134] The title compound was prepared as detailed below (see also
Scheme 1)
##STR00017## ##STR00018##
Step A: 2-Butyl acrylic acid
[0135] To a solution of n-butylmalonic acid (17.2 g, 107 mmol) in
ethanol (200 ml) was added piperidine (12.76 ml, 129 mmol) and 37%
aq. formaldehyde (40.3 ml, 538 mmol). The solution was heated to
80.degree. C. during which time a precipitate appeared and
gradually redissolved over 1 hour. The reaction mixture was stirred
at 80.degree. C. overnight then cooled to room temperature. The
solvents were removed under reduced pressure and the residue was
dissolved in ethyl acetate (200 ml), washed successively with 1 M
hydrochloric acid and brine, dried over anhydrous magnesium sulfate
and filtered. The filtrate was concentrated to give the title
compound as a clear oil (13.37 g, 97%). .sup.1H-NMR; .delta.
(CDCl.sub.3), 6.29 (1H, s), 5.65 (1H, s), 2.34-2.28 (2H, m),
1.54-1.26 (4H, m), 0.94 (3H, t, J=7.1 Hz).
Step B:
4S-Benzyl-3-(2-butyl-acryloyl)-5,5-dimethyl-oxazolidin-2-one
[0136] 2-Butyl acrylic acid (21.5 g, 168 mmol) was dissolved in dry
THF (500 ml) and cooled to -78.degree. C. under a blanket of argon.
Triethylamine (30 ml, 218 mmol) and pivaloyl chloride (21 ml, 168
mmol) were added at such a rate that the temperature remained below
-60.degree. C. The mixture was stirred at -78.degree. C. for 30
minutes, warmed to room temperature for 2 hours and finally cooled
back to -78.degree. C.
[0137] In a separate flask, 4S-benzyl-5,5-dimethyl-oxazolidin-2-one
was dissolved in dry THF (500 ml) and cooled to -78.degree. C.
under a blanket of argon. n-Butyllithium (2.4 M solution in
hexanes, 83 ml, 200 mmol) was added slowly and the mixture was
stirred for 30 minutes at room temperature. The resulting anion was
transferred via a cannula into the original reaction vessel. The
mixture was allowed to warm to room temperature and was stirred
overnight at room temperature. The reaction was quenched with 1 M
potassium hydrogen carbonate (200 ml) and the solvents were removed
under reduced pressure. The residue was partitioned between ethyl
acetate and water. The organic layer was washed with brine, dried
over anhydrous magnesium sulfate, filtered and concentrated under
reduced pressure to give an orange oil. TLC analysis revealed the
presence of unreacted chiral auxiliary in addition to the required
product. A portion of the material (30 g) was dissolved in
dichloromethane and flushed through a silica pad to give pure title
compound as a yellow oil (25.3 g). .sup.1H-NMR; .delta.
(CDCl.sub.3), 7.31-7.19 (5H, m), 5.41 (2H,s), 4.51 (1H, dd, J=9.7
& 4.2 Hz), 3.32 (1H, dd, J=14.2 & 4.2 Hz), 2.82 (1H, dd,
J=14.2 & 9.7 Hz), 2.40-2.34 (2H, m), 1.48-1.32 (4H, m), 1.43
(3H, s), 1.27 (3H, s), 0.91 (3H, t, J=7.1 Hz). Some chiral
auxiliary was recovered by flushing the silica pad with
methanol.
Step C:
4S-Benzyl-3-[2-(benzyloxyamino-methyl)-hexanoyl]-5,5-dimethyl-oxaz-
olidin-2-one (p-toluenesulfonic acid salt)
[0138] 4S-Benzyl-3-(2-butyl-acryloyl)-5,5-dimethyl-oxazolidin-2-one
(19.8 g, 62.8 mmol) was mixed with O-benzylhydroxylamine (15.4 g,
126 mmol) and stirred overnight at room temperature. The mixture
was dissolved in ethyl acetate and the solution was washed with 1 M
hydrochloric acid, 1 M sodium carbonate and brine, dried over
anhydrous magnesium sulfate and filtered. The filtrate was
concentrated under reduced pressure to afford a pale yellow oil
(25.3 g) which was shown by NMR and HPLC analysis to contain
4S-benzyl-3-[2-(benzyloxyamino-methyl)-hexanoyl]-5,5-dimethyl-oxa-
zolidin-2-one (ca. 82% d.e.) along with a trace of starting
material. The product was combined with another batch (26.9 g, 76%
d.e.) and dissolved in ethyl acetate (200 ml). p-Toluenesulfonic
acid (22.7 g, 119 mmol) was added and the mixture was cooled to
0.degree. C. The title compound was obtained as a white crystalline
solid by seeding and scratching. Yield: 25.2 g, (34%, single
diastereoisomer). A second crop (14.7 g, 20%, single
diastereoisomer) was also obtained. .sup.1H-NMR; .delta.
(CDCl.sub.3), 7.89 (2H, d, J=8.2 Hz), 7.37-7.12 (10H, m), 7.02 (2H,
d, J=6.9 Hz), 5.28-5.19 (2H, m), 4.55 (1H, m), 4.23 (1H, m), 3.93
(1H, m), 3.58 (1H, m), 2.58 (1H, m), 2.35 (3H, s), 1.67-1.51 (2H,
m), 1.29-1.16 (4H, m), 1.25 (3H, s), 1.11 (3H, s), 0.80-0.75 (3H,
m).
Step D: 2R-(Benzyloxyamino-methyl)-hexanoic acid
[0139]
4S-Benzyl-3-[2R-(benzyloxyamino-methyl)-hexanoyl]-5,5-dimethyl-oxaz-
olidin-2-one p-toluenesulfonic acid salt (25.2 g, 40.2 mmol) was
partitioned between ethyl acetate and 1 M sodium carbonate. The
organic phase was dried over anhydrous magnesium sulfate, filtered
and evaporated under reduced pressure. The residual oil was
dissolved in THF (150 ml) and water (50 ml), cooled to 0.degree. C.
and treated with lithium hydroxide (1.86 g, 44.2 mmol). The
solution was stirred for 30 minutes at 0.degree. C., then overnight
at room temperature. The reaction was acidified to pH4 with 1 M
citric acid and the solvents were removed. The residue was
partitioned between dichloromethane and 1 M sodium carbonate. The
basic aqueous layer was acidified to pH4 with 1M citric acid and
extracted three times with ethyl acetate. The combined organic
layers were dried over anhydrous magnesium sulfate, filtered and
concentrated to provide the title compound as a colourless oil (7.4
g, 73%). .sup.1H-NMR; .delta. (CDCl.sub.3), 8.42 (2H, br s),
7.34-7.25 (5H, m), 4.76-4.66 (2H, m), 3.20-3.01 (2H, m), 2.73 (1H,
m), 1.70-1.44 (2H, m), 1.34-1.22 (4H, m) and 0.92-0.86 (3H, m).
Step E: 2R-[(Benzyloxy-formylamino)-methyl)]-hexanoic acid
[0140] To a solution of 2R-(Benzyloxyamino-methyl)-hexanoic acid
(30.6 g, 0.12 mol) in dry THF (300 ml) was added formic acetic
anhydride (26.8 ml, 0.31 mol) at 0.degree. C. Triethylamine (18.5
ml, 0.13 mol) was added and the reaction was stirred for 1 h at
0.degree. C. and 60 h at room temperature. The solvent was removed
in vacuo to yield the title compound as a yellow oil (33.6 g, 99%)
which was used in Step F without further purification. .sup.1H-NMR;
(CDCl.sub.3, rotamers), 8.20-8.08 (0.7H, br s), 8.07-7.92 (0.3H, br
s), 7.50-7.25 (5H, br m), 5.07-4.70 (2H, br m), 3.95-3.52 (2H, br
m), 2.90-2.66 (1H, br s), 1.72-1.20 (6H, br m), 1.00-0.78 (3H, br
s). LRMS: +ve ion 280 [M+1].
Step F: 2R-[(Benzyloxy-formyl-amino)-methyl]hexanoic acid
pentafluoro-phenyl ester
[0141] To a solution of
2R-[(Benzyloxy-formylamino)-methyl)]-hexanoic acid (7.8 g, 19.9
mmol) in dry THF (500 ml) was added pentafluorophenol (44.3 g, 0.24
mol), EDC (27.7 g, 0.14 mol) and HOBt (16.2 g, 0.12 mol). The
reaction was stirred overnight at room temperature. The solvent was
removed in vacuo and the residue was dissolved in ethyl acetate,
washed successively with 1 M sodium carbonate (3.times.500 ml) and
water (1.times.500 ml), dried over anhydrous magnesium sulfate and
filtered. The solvent was removed in vacuo to yield a yellow oil
(60 g) that was purified by flash chromatography (5:1, hexane:ethyl
acetate.fwdarw.1:2 hexane:ethyl acetate) to yield a clear oil (42.0
g, 79%). .sup.1H-NMR; .delta. (CDCl.sub.3, rotamers), 8.20-8.09
(0.7H, br s), 8.09-7.92 (0.3H, br s), 7.60-7.21 (5H, br m),
5.00-4.70 (2H, br m), 4.04-3.72 (2H, br m), 3.18-3.00 (1H, br s),
1.85-1.57 (2H, br m), 1.50-1.26 (4H, br m), 1.00-0.82 (3H, br m);
LRMS: 466 [M+H].
Step G: 2R-[(Benzyloxy-formyl-amino)-methyl]-hexanoic acid
{1S-[4-(4-methoxy-benzoyl)-piperidine-1-carbonyl]-2,2-dimethyl-propyl}-am-
ide
[0142] 2R-[(Benzyloxy-formyl-amino)methyl]-hexanoic acid
pentafluorophenyl ester (231 mg, 0.52 mmol) and
2S-amino-1-[4-(4-methoxy-benzoyl)-piperidin-1-yl]-3,3-dimethyl-butan-1-on-
e (prepared from N-benzyloxycarbonyl-L-tert-leucine) (259 mg, 0.78
mmol) were dissolved in dichloromethane (6 ml) and the mixture was
stirred overnight at 27.degree. C. An excess of Amberlyst A-21 ion
exchange resin was added and the mixture stirred for 2.5 hrs before
filtration. The resulting solution was then treated with methyl
isocyanate polystyrene resin for 5 hrs. The mixture was filtered
and solvent was removed under reduced pressure. Mass spectrometric
analysis showed presence of pentafluorophenol, so the residue was
dissolved in methanol (5 ml) and an excess of A-26 carbonate resin
was added. The mixture was stirred overnight before filtration and
removal of solvent under reduced pressure to afford the title
compound as a brown oil (358 mg, 0.60 mmol). LRMS: +ve ion 594
[M+H].
Step H: 2R-[(Formyl-hydroxy-amino)-methyl]hexanoic acid
{1S-[4-(4-methoxy-benzoyl)-piperidine-1-carbonyl]-2,2-dimethyl-propyl}-am-
ide
[0143] 2R-[(Benzyloxy-formyl-amino)-methyl]-hexanoic acid
{1S-[4-(4-methoxy-benzoyl)-piperidine-1-carbonyl]-2,2-dimethyl-propyl}-am-
ide (358 mg, 0.60 mmol) was dissolved in ethanol (6 ml).
Cyclohexene (0.60 ml) was added and the mixture placed under a
blanket of argon. A suspension of 10% palladium on charcoal (40 mg)
in ethyl acetate (1 ml) was added and the mixture was stirred at
70.degree. C. for 5 hrs. The reaction mixture was cooled and the
catalyst removed by filtration. The filtrate was concentrated to
provide the title compound as a brown oil (294 mg, 0.58 mmol).
Characterising data are provided in Table 1.
[0144] The compounds of Examples 2-13 were prepared by the
synthetic route outlined in Scheme 1 and as described in detail for
Example 1. Steps G and H were carried out in parallel for all
examples. L-tert-leucine derivatives were prepared according to
established literature methods. Purification of the final
compounds, where necessary, was carried out by preparative
HPLC.
TABLE-US-00002 TABLE 1 Mass Spec. Example Structure Data HPLC 1
##STR00019## [M + H] = 504 RT = 21.7 mins 88% pure 2 ##STR00020##
[M + H] = 487 RT = 20.1 mins 85% pure 3 ##STR00021## [M + H] = 505
[M - H] = 503 RT = 17.3 mins 83% pure 4 ##STR00022## [M + H] = 447
[M - H] = 445 RT = 21.5 mins 90% pure 5 ##STR00023## [M + H] = 478
[M + Na] = 500 [M - H] = 476 RT = 20.8 mins 95% pure 6 ##STR00024##
[M + H] = 465 [M - H] = 463 RT = 20.6 mins 93% pure 7 ##STR00025##
[M + H] = 502 [M + Na] = 524 [M - H] = 500 RT = 19.3 mins 94% pure
8 ##STR00026## [M + Na] = 496 [M - H] = 472 RT = 21.2 mins 91% pure
9 ##STR00027## [M + H] = 537 [M - H] = 535 RT = 19.8 mins 95% pure
10 ##STR00028## [M + H] = 475 [M - H] = 473 RT = 24.3 mins 87% pure
11 ##STR00029## [M + H] = 477 [M - H] = 475 RT = 20.3 mins 84% pure
12 ##STR00030## [M + Na] = 487 [M - H] = 463 RT = 18.7 mins 94%
pure 13 ##STR00031## [M + H] = 502 RT = 21.0 mins 88% pure 14
##STR00032## [M + H] = 512 [M - H] = 510 RT = 21.7 mins 84% pure 15
##STR00033## [M + H] = 491 [M - H] = 489 RT = 18.7 mins 98% pure 16
##STR00034## [M + Na] = 650 [M - H] = 626 RT = 21.5 mins 86% pure
17.sup.# ##STR00035## [M + H] = 546 [M - H] = 544 RT = 22.8 mins
88% pure .sup.#1H-NMR; .delta. (CD.sub.3OD, rotamers), 8.26 (0.4H,
s), 7.84 (0.6H, s), 7.69 (2H, m), 7.39 (2H, m), 6.49 (0.4H, s),
6.42 (0.6H, s), 5.01 (0.6H, s), 4.96 (0.4H, s), 4.64 (0.6H, d, J =
13.1 Hz), 4.51 (0.4H, d, J = 13.2 Hz), 4.36 (0.6H, d, J = 13.2 Hz),
4.29 (0.4H, d, J = 13.6 Hz), 3.10 (1H, m), 3.43 (0.4H, m), 3.32
(0.6H, m), 3.00 (2H, m), 2.86 (2H, m), 2.09 (2H, m), 1.59 (4H, m),
1.27 (4H, m), 1.02 (9H, m), 0.90 (1.4H, s) and 0.79 (1.6H, s).
[0145] The compounds of Examples 18 to 40 were prepared from
2R-[(Benzyloxy-formyl-amino)-methyl]-hexanoic acid
pentafluorophenyl ester in a similar way to Example 1 but with the
following modifications.
Step G: Generic Experimental Procedure for the Synthesis of an
Array of Amides
[0146] The coupling of amines to the pentafluorophenyl ester were
carried out on a Zymate XPII laboratory robot. To a solution of the
pentafluorophenyl ester (55.8 mg, 0.12 mmol) in dichoromethane (2
ml) were added the individual amines (0.25 mmol) and the reaction
mixtures were stirred at room temperature for 60 h. Purification
was effected by removing excess amine and pentafluorophenol using
scavenger resins. The pentafluorophenol was removed using a three
fold excess (0.36 mmol) of A-26 carbonate resin (3.5 mmol loading).
The resin was added to the reaction mixtures and agitated for 24 h,
after which time it was filtered off. The excess amines were
removed using a three fold excess (0.36 mmol) of methylisocyanate
polystyrene resin (1.2 mmol loading). The resin was added to the
reaction mixtures and agitated for 4 h, after which time it was
filtered off. The solvent was removed in vacuo using a Savant Speed
Vac Plus to yield the coupled products. Yields were not calculated
and the purity and integrity of each compound was verified using
HPLC and LRMS.
Step H: Generic Transfer Hydrogenation Procedure
[0147] Coupled products from Step G were taken up in an
ethanol-cyclohexene solution (3 ml, 10% in cyclohexene) and Pd/C
(20% w/w) was added and the reactions stirred at 80.degree. C. for
24 h. The Pd/C was filtered off and the solvent was removed in
vacuo using a Savant Speed Vac Plus to yield the title compounds
(Examples 18 to 40, Table 2). Yields were not calculated and the
purity and integrity of each compound was verified using HPLC and
LRMS.
TABLE-US-00003 TABLE 2 Example Structure Mass Spectral Data HPLC
Purification 18 ##STR00036## 336 (M + 1, 70) RT 7.5 min 100% Ion
exchange resin, Prep HPLC 19 ##STR00037## 368 (M + 1, 100) RT 21.8
min 80% Resins, Prep HPLC 20 ##STR00038## 392 (M + 1, 100) RT 8.2
min 100% Resins Prep HPLC 21 ##STR00039## 378 (M + 1, 70) 362([M +
1] - Me, 100) RT 12.0 min and 12.2 min (diastereomers) >98%
Resins Prep HPLC 22 ##STR00040## 376 (M + 1, 100) RT 18.5 min 100%
Resins 23 ##STR00041## 424 (M + 1, 30) 258 ([M = 1] -
[C.sub.6H.sub.5].sub.2CH, 100 RT 17.5 min 95% Resins 24
##STR00042## 333 (M + 1, 30) RT 21.6 min 100% Resins 25
##STR00043## 421 (M + 1 - H.sub.2O, 50) 437 (M - 1, 60) RT 22.3 min
100% Resins prep HPLC 26 ##STR00044## 334 (M + 1, 100) RT 17.7 min
100% Resins 27 ##STR00045## 458 (M + 1, 20) 258 [(M + 1] -
[C.sub.6H.sub.5]C.sub.6H.sub.4ClCH, 100) RT 26.4 min 100% Resins
prep HPLC 28 ##STR00046## 368 (M + 1, 100) RT 22.1 min 100% Resins
prep HPLC 29 ##STR00047## 346 (M + 1, 100) 2 peaks, RT 3.2 min and
3.6 min 100% Resins 30 ##STR00048## 316 (M + 1, 100) 2peaks, RT 3.1
min and 3.5 min 100% Resins 31 ##STR00049## 283 ([M + 1] -
H.sub.2O, 90) 1 peak with shoulder, RT 16.8 min Resins 32
##STR00050## 402 (M + 1, 100) RT 15.80 min >95% Resins 33
##STR00051## 364 (M + 1, 100) RT 11.7 min >95% Resins 34
##STR00052## 403 (M + 1, 100) RT 14.7 min 95% Resins 35
##STR00053## 373 (M + 1, 100) RT 14.5 min 95% Resins 36
##STR00054## 460 (M + 1, 100) RT 13.3 min >95% Resins, prep HPLC
37 ##STR00055## 379 (M + 1, 100) RT 13.6 min >95% Resins 38
##STR00056## 352 (M + 1, 100) RT 5.9 min >95% Resins 39
##STR00057## 352 (M + 1, 100) RT 11.3 min >95% Resins 40
##STR00058## 362 (M + 1, 100) RT 15.7 min >95% Resins
[0148] The compounds of the Examples 1-40 are named as follows:
Example 1
[0149] 2R-[Formyl-hydroxy-amino)methyl]-hexanoic acid [0150]
51{1S-[4-(4-methoxy-benzoyl)-piperidine-1-carbonyl]-2,2-dimethyl-propyl}--
amide
Example 2
[0150] [0151] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
[0152]
[1S-(4-benzotriazol-1-yl-piperidine-1-carbonyl)-2,2-dimethyl-propyl]-amid-
e
Example 3
[0152] [0153] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[0154]
[1S-(4-benzo[1,3]dioxol-5-ylmethyl-piperazine-1-carbonyl)-2,2-dimethyl-pr-
opyl]-amide
Example 4
[0154] [0155] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[0156]
[2,2-dimethyl-1S-(4-phenyl-piperidine-1-carbonyl)-propyl]-amide
Example 5
[0156] [0157] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
[0158]
[1S-(6,7-dimethoxy-3,4-dihydro-1H-isoquinoline-2-carbonyl)-2,2-dimethyl-p-
ropyl]-amide
Example 6
[0158] [0159] 2R-[(Formyl-hydroxy-amino)-methyl]hexanoic acid
[0160]
{1S-[4-(4-fluoro-phenyl)-piperidine-1-carbonyl]-2,2-dimethyl-propyl}-amid-
e
Example 7
[0160] [0161] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[0162]
{2,2-dimethyl-1S-[4-(2-oxo-2,3-dihydro-benzoimidazol-1-yl)-piperidine-1-c-
arbonyl]-propyl}-amide
Example 8
[0162] [0163] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
[0164]
[1S-(4-benzoyl-piperidine-1-carbonyl)-2,2-dimethyl-propyl]-amide
Example 9
[0164] [0165] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[0166]
[1S-(4-benzhydryl-piperazine-1-carbonyl)-2,2-dimethyl-propyl]-amide
Example 10
[0166] [0167] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
[0168]
{1S-[4-(2,5-dimethyl-phenyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}--
amide
Example 11
[0168] [0169] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[0170]
{1S-[4-(2-methoxy-phenyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}-ami-
de
Example 12
[0170] [0171] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[0172]
{1S-[4-(furan-3-carbonyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}-ami-
de
Example 13
[0172] [0173] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[0174]
{1S-[4-(5-furan-2-yl-2H-pyrazol-3-yl)-piperidine-1-carbonyl]-2,2-dimethyl-
-propyl}-amide
Example 14
[0174] [0175] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[0176]
{2,2-dimethyl-1S-[4-(5-phenyl-2H-pyrazol-3-yl)-piperidine-1-carbonyl]-pro-
pyl}-amide
Example 15
[0176] [0177] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[0178]
{1S-[4-(4-methoxy-phenyl)-3-methyl-piperazine-1-carbonyl]-2,2-dimethyl-pr-
opyl}-amide
Example 16
[0178] [0179] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
[0180]
{1S-[1-(3,4-dimethoxy-benzyl)-6,7-dimethoxy-3,4-dihydro-1H-isoquinoline-2-
-carbonyl]-2,2-dimethyl-propyl}-amide
Example 17
[0180] [0181] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[0182]
(1S-{4-[5-(2-chloro-phenyl)-2H-pyrazol-3-]-piperidine-1-carbonyl}-2,2-dim-
ethyl-prop yl)-amide
Example 18
[0182] [0183]
N-Hydroxy-N-[2R-(4-pyrimidin-2-yl-piperazine-1-carbonyl)-hexyl]-formamide
Example 19
[0183] [0184]
N-{2R-[4-(4-Chloro-phenyl)-piperazine-1-carbonyl]-hexyl}-N-hydroxy-formam-
ide
Example 20
[0184] [0185]
N-[2R-(4-benzo[1,3]dioxol-5-ylmethyl-piperazine-1-carbonyl)-hexyl]-N-hydr-
oxy-formamide
Example 21
[0185] [0186]
N-Hydroxy-N-{2R-[4-(4-methoxy-phenyl)-3-methyl-piperazine-1-carbonyl]-hex-
yl}-formamide
Example 22
[0186] [0187]
N-{2R-[4-(4-Acetyl-phenyl)-piperazine-1-carbonyl]-hexyl}-N-hydroxy-formam-
ide
Example 23
[0187] [0188]
N-[2R-(4-Benzhydryl-piperazine-1-carbonyl)-hexyl]-N-hydroxy-formamide
Example 24
[0188] [0189]
N-Hydroxy-N-[2R-(4-phenyl-piperidine-1-carbonyl)-hexyl]-formamide
Example 25
[0189] [0190]
N-Hydroxy-N-{2R-[4-(hydroxy-diphenyl-methyl)-piperidine-1-carbonyl]-hexyl-
}-formamide
Example 26
[0190] [0191]
N-Hydroxy-N-[2R-(4-phenyl-piperazine-1-carbonyl)-hexyl]-formamide
Example 27
[0191] [0192]
N-(2R-{4-[(4-Chloro-phenyl)-phenyl-methyl]-piperazine-1-carbonyl}-hexyl)--
N-hydroxy-formamide
Example 28
[0192] [0193]
N-{2R-[4-(3-Chloro-phenyl)-piperazine-1-carbonyl]-hexyl}-N-hydroxy-formam-
ide
Example 29
[0193] [0194]
N-Hydroxy-N-(2R-{4-[2-(2-hydroxy-ethoxy)-ethyl]-piperazine-1-carbonyl}-he-
xyl)-formamide
Example 30
[0194] [0195]
N-Hydroxy-N-{2R-[4-(3-hydroxy-propyl)-piperazine-1-carbonyl]-hexyl}-forma-
mide
Example 31
[0195] [0196]
N-Hydroxy-N-{2R-[2-(2-hydroxy-ethyl)-piperazine-1-carbonyl]-hexyl}-formam-
ide
Example 32
[0196] [0197]
N-{2R-[4-(3,4-Dichloro-phenyl)-piperazine-1-carbonyl]-hexyl}-N-hydroxy-fo-
rmamide
Example 33
[0197] [0198]
N-Hydroxy-N-{2R-[4-(4-methoxy-phenyl)-piperazine-1-carbonyl]-hexyl}-forma-
mide
Example 34
[0198] [0199]
N-Hydroxy-N-{2R-[4-(3-trifluoromethyl-pyridin-2-yl)-piperazine-1-carbonyl-
]-hexyl}-formamide
Example 35
[0199] [0200]
N-Hydroxy-N-{2R-[4-(1H-indol-7-yl)-piperazine-1-carbonyl]-hexyl}-formamid-
e
Example 36
[0200] [0201]
N-(2R-{4-[Bis-(4-fluoro-phenyl)-methyl]-piperazine-1-carbonyl}-hexyl)-N-h-
ydroxy-formamide
Example 37
[0201] [0202]
N-Hydroxy-N-{2R-[4-(4-nitro-phenyl)-piperazine-1-carbonyl]-hexyl}-formami-
de
Example 38
[0202] [0203]
N-{2R-[4-(4-Fluoro-phenyl)-piperazine-1-carbonyl]-hexyl}-N-hydroxy-formam-
ide
Example 39
[0203] [0204]
N-{2R-[4-(Furan-2-carbonyl)-piperazine-1-carbonyl]-hexyl}-N-hydroxy-forma-
mide
Example 40
[0204] [0205]
N-{2R-[4-(2,5-Dimethyl-phenyl)-piperazine-1-carbonyl]-hexyl}-N-hydroxy-fo-
rmamide
[0206] The compounds of Examples 41 and 42 below were prepared in
solution by parallel synthesis. The general synthetic route (Scheme
B) is outlined in detail below for Example 41.
2R-Cyclopentylmethyl-succinic acid 4-tert-butyl ester was prepared
by analogy with methods in patent application number WO
92/13831
##STR00059##
Example 41
The preparation of
3R-Cyclopentylmethyl-4-[4-(4-fluoro-phenyl)-piperazin-1-yl]-N-hydroxy-4-o-
xo-butyramide
Step A:
3R-Cyclopentylmethyl-4-[4-(4-fluoro-phenyl)-piperazin-1-yl]-4-oxo--
butyric acid tert-butyl ester
[0207] To a solution of 2R-Cyclopentylmethyl-succinic acid
4-tert-butyl ester 1 (250 mg, 1.0 mmol) in dichloromethane (5 ml)
was added PyBOP (670 mg, 1.3 mmol), HOAt (145 mg, 1.0 mmol), DIPEA
(278 .mu.l, 1.7 mmol) and amine (211 mg, 1.2 mmol), the reaction
mixture was stirred at room temperature for 24 h. The solvent was
removed in vacuo to yield an orange oil (800 mg), which was taken
up in ethyl acetate (50 ml) and was washed with 1M sodium carbonate
(2.times.50 ml), water (1.times.50 ml) and dried over anhydrous
magnesium sulphate. The solvent was removed in vacuo to yield the
title compound as a yellow oil (600 mg), which was purified by
preparative HPLC.
Step B:
3R-Cyclopentylmethyl-4-[4-(4-fluoro-phenyl)-piperazin-1-yl]-4-oxo--
butyric acid
[0208] To a solution of
3R-Cyclopentylmethyl-4-[4-(4-fluoro-phenyl)-piperazin-1-yl]-4-oxo-butyric
acid tert-butyl ester in dichloromethane (3 ml) was added TFA (2
ml) at 0.degree. C., the reaction mixture was stirred at 0.degree.
C. for 0.5 h and at room temperature for 1.5 h, after which time no
starting material remained. The solvent was removed in vacuo and
the TFA was azeotroped with toluene to yield the title compound as
an orange oil (364 mg), which was progressed to the next step
without further purification.
Step C:
3R-Cyclopentylmethyl-4-[4-(4-fluoro-phenyl)-piperazin-1-yl]-N-hydr-
oxy-4-oxo-butyramide
[0209] To a solution of
3R-Cyclopentylmethyl-4-[4-(4-fluoro-phenyl)-piperazin-1-yl]-4-oxo-butyric
acid (364 mg, 1.0 mmol) in dichloromethane (3 ml) was added PyBOP
(575 mg, 1.1 mmol), HOAt (14 mg, 0.1 mmol), and Et.sub.3N (279
.mu.l, 2.0 mmol). To a solution of hydroxylamine hydrochloride (105
mg, 1.5 mmol) in a separate flask in DMF (2 ml) was added NMM (161
.mu.l, 1.5 mmol). This solution was then added to the solution of
acid and the reaction mixture was stirred at RT for 60 h. The
solvent was removed in vacuo and the resulting residue was taken up
in dichloromethane (5 ml) and was washed with 1M sodium carbonate
(1.times.5 ml), water (1.times.5 ml) dried over anhydrous magnesium
sulphate and the solvent removed in vacuo to yield a yellow oil
(520 mg). The product was purified by prep HPLC. LRMS -ve ion: 376
(M-1, 80%), P; +ve ion 345 ([M+1]-32, 40%), P--NHOH; HPLC data: RT
5.6 min 97%
[0210] The following compound was prepared in a manner identical to
that of Example 41 starting with 2R-Cyclopentylmethyl-succinic acid
4-tert-butyl ester and 3,4-dichloro-phenyl-piperazine.
Example 42
3R-Cyclopentylmethyl-4-[4-(3,4-dichloro-phenyl)-piperazin-1-yl]-N-hydroxy--
4-oxo-butyramide
##STR00060##
[0212] The title compound was purified by preparative HPLC. LRMS
-ve ion: 326 (M-1, 40%); +ve ion: 395 ([M+1]-32, 40%), P--NHOH;
HPLC data: RT 6.4 min, 98%.
Example 43
2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(4-cyano-benzyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}-amide
##STR00061##
[0214] The title compound was prepared as detailed below (see
Scheme 2) from 2R-[(Benzoyloxy-formylamino)-methyl]-hexanoic acid
(see Scheme 1).
##STR00062##
Step A: 2R-[(Benzyloxy-formyl-amino)-methyl]-hexanoic acid
{2,2-dimethyl-1S-[4-(2-phenoxy-acetyl)-piperazine-1-carbonyl]-propyl}-ami-
de
[0215] To a solution of
2R-[(Benzoyloxy-formylamino)-methyl]-hexanoic acid (7.0 g, 25
mmols) in DMF was added EDC (5.3 g, 27.5 mmol),
4-(2S-Amino-3,3-dimethyl-butyryl)-piperazine-1-carboxylic acid
benzyl ester (10.0 g, 30 mmol) and HOAt (0.34 g, 2.5 mmol). The
reaction was stirred overnight at room temperature. The solvent was
removed in vacuo and the residue was dissolved in ethyl acetate,
washed successively with 1M hydrochloric acid, 1M sodium carbonate
and saturated sodium chloride solution, dried over anhydrous
magnesium sulfate and filtered. The solvent was removed in vacuo to
yield a yellow oil (9.6 g) that was purified by flash
chromatography (3% methanol/DCM) to yield a white foam (6.7 g,
45%). .sup.1H-NMR; (CDCl.sub.3, rotamers), 8.13 (0.6H, s), 7.89
(0.4H, s), 7.36 (10H, m), 6.26 (1H, d, J=9.2 Hz), 5.15 (2H, s),
4.88 (2H, m), 4.82 (1H, d, J=9.3 Hz), 3.56 (10H, m), 2.54 (1H, m),
1.25 (6H, m), 0.94 (9H, s), 0.83 (3H, t, J=6.9 Hz). LRMS: +ve ion
617 [M+Na].
Step B: 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[2,2-dimethyl-1S-(piperazine-1-carbonyl)-propyl]-amide
[0216] To a solution of
2R-[(Benzyloxy-formyl-amino)-methyl]-hexanoic acid
{2,2-dimethyl-1S-[4-(2-phenoxy-acetyl)-piperazine-1-carbonyl]-propyl}-ami-
de (6.5 g, 11 mmol) in ethanol (100 ml), under a blanket of argon,
was added a suspension of 10% palladium on charcoal (670 mg) in
ethyl acetate (15 ml). Hydrogen was bubbled through the suspension
for 30 minutes and then the reaction was stirred under an
atmosphere of hydrogen for 3 hours 45 minutes. The palladium
catalyst was filtered off and the solvent removed in vacuo to yield
a white foam (4.28 g. 100%). .sup.1H-NMR; (CDCl.sub.3, rotamers),
8.39 (0.3H, s), 7.80 (0.7H, s), 6.82 (1H, m), 4.90 (1H, m), 3.87
(3H, m), 3.50 (3H, m), 2.80 (5H, m), 1.39 (6H, m), 0.99 (3H, s),
0.95 (6H, s), 0.87 (3H, t, J=6.7 Hz). LRMS +ve ion 397 [M+1], 419
[M+Na], -ve ion 395 [M-1].
Step C: 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(4-cyano-benzyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}-amide
[0217] To a stirred solution of
2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[2,2-dimethyl-1S-(piperazine-1-carbonyl)-propyl]-amide in
dichloromethane (4 ml) was added triethylamine (85 .mu.l, 0.6 mmol)
and p-nitrile benzyl bromide (110 mg, 0.56 mmol). The reaction
mixture was stirred at room temperature overnight. The solvent was
removed in vacuo to yield a yellow oil that was purified by
preparative HPLC to obtain a white foam (108 mg, 44%)
Characterisation data is provided in Table 2.
[0218] The compounds of Examples 44-48 were prepared by the
synthetic route outlined in Scheme 2 and as described in detail for
Example 43. Step C was carried out in parallel for all examples.
Characterisation data for the compounds is provided in Table 2.
Examples 49-54 were prepared from
2R-[(Benzyloxy-formyl-amino)-methyl]-3-cyclopentyl-propionic acid
in a similar manner. Characterisation data for the compounds is
provided in Table 3. L-tert-leucine derivatives were prepared
according to established literature methods. Purification of the
final compounds, where necessary, was carried out by preparative
HPLC.
TABLE-US-00004 TABLE 2 ##STR00063## LCMS Reten- tion LCMS Exam-
LCMS ions time Purity ple R = seen (min) % 43 ##STR00064## M + 1 =
486 M + Na = 508 2.6 >90 44 ##STR00065## M + 1 = 486 M + Na =
508 2.65 >90 45 ##STR00066## M + 1 = 486 M + Na = 508 2.6 >90
46 ##STR00067## M + 1 = 537 M + Na = 559 3.65 >90 47
##STR00068## M + 1 = 537 M + Na = 559 3.58 >90 48 ##STR00069## M
+ 1 = 511 M + Na = 533 3.38 >90
TABLE-US-00005 TABLE 3 ##STR00070## LCMS Reten- tion LCMS Exam-
LCMS ions time Purity ple R = seen (mins) % 49 ##STR00071## M + 1 =
512 M + Na = 534 2.97 >90 50 ##STR00072## M + 1 = 512 M + Na =
534 3.02 >90 51 ##STR00073## M + 1 = 512 M + Na = 534 2.95
>90 52 ##STR00074## M + 1 = 563 3.88 >90 53 ##STR00075## M +
1 = 563 M + Na = 585 3.83 >90 54 ##STR00076## M + 1 = 537 M + Na
= 559 3.63 >90
[0219] The compounds of examples 44-54 are named as follows:
Example 44
[0220] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
{1S-[4-(2-cyano-benzyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}-amide
Example 45
[0220] [0221] 2R-[(Formyl-hydroxy-amino)-methyl]hexanoic acid
{1S-[4-(3-cyano-benzyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}-amide
Example 46
[0221] [0222] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[1S-(4-biphenyl-4-ylmethyl-piperazine-1-carbonyl)-2,2-dimethyl-propyl]-am-
ide
Example 47
[0222] [0223] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[1S-(4-biphenyl-2-ylmethyl-piperazine-1-carbonyl)-2,2-dimethyl-propyl]-am-
ide
Example 48
[0223] [0224] 2R-[(Formyl-hydroxy-amino)-methyl]hexanoic acid
[2,2-dimethyl-1S-(4-naphthalen-2-ylmethyl-piperazine-1-carbonyl)-propyl]--
amide
Example 49
[0224] [0225]
N-{1S-[4-(4-Cyano-benzyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}-2R--
cyclopentylmethyl-3-(formyl-hydroxy-amino)-propionamide
Example 50
[0225] [0226]
N-{1S-[4-(2-Cyano-benzyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}-2R--
cyclopentylmethyl-3-(formyl-hydroxy-amino)-propionamide
Example 51
[0226] [0227]
N-{1S-[4-(3-Cyano-benzyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}-2S--
cyclopentylmethyl-3-(formyl-hydroxy-amino)-propionamide
Example 52
[0227] [0228]
N-[1S-(4-Biphenyl-4-ylmethyl-piperazine-1-carbonyl)-2,2-dimethyl-propyl]--
2R-cyclopentylmethyl-3-(formyl-hydroxy-amino)-propionamide
Example 53
[0228] [0229]
N-[1S-(4-Biphenyl-2-ylmethyl-piperazine-1-carbonyl)-2,2-dimethyl-propyl]--
2R-cyclopentylmethyl-3-(formyl-hydroxy-amino)-propionamide
Example 54
[0229] [0230]
2R-Cyclopentylmethyl-N-[2,2-dimethyl-1S-(4-naphthalen-2-ylmethyl-piperazi-
ne-1-carbonyl)-propyl]-3-(formyl-hydroxy-amino)-propionamide
Example 55
2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S+[4-(3a,7a-dihydro-benzo[1,3]dioxole-5-carbonyl)-piperazine-1-carbonyl-
]-2,2-dimethyl-propyl}-amide
##STR00077##
[0232] Example 55 was prepared from
2R-[(Benzoyloxy-formylamino)-methyl]-hexanoic acid by analogy with
methods described in Scheme 1.
2-Amino-1S-[4-(3a,7a-dihydro-benzo[1,3]dioxole-5-carbonyl)-piperazin-1-yl-
]-3,3-dimethyl-butan-1-one was prepared as detailed below (Scheme
3).
##STR00078##
Step A:
{1S-[4-(3a,7a-Dihydro-benzo[1,3]dioxole-5-carbonyl)-piperazine-1--
carbonyl]-2,2-dimethyl-propyl}-carbamic acid benzyl ester
[0233] To a solution of
[2,2-Dimethyl-1S-(piperazine-1-carbonyl)-propyl]-carbamic acid
benzyl ester (3.2 g, 9.6 mmol) in anhydrous dichloromethane (50 ml)
under an atmosphere of argon, was added triethylamine (2.8 ml, 20
mmol) and 3,4 methylenedioxybenzoyl chloride (2.0 g, 10.8 mmol).
The reaction was stirred overnight at room temperature. The
reaction mixture was diluted with dichloromethane, washed
successively with 1M hydrochloric acid, 1M sodium carbonate and
saturated sodium chloride solution, dried over anhydrous magnesium
sulfate and filtered. The solvent was removed in vacuo to yield a
yellow oil which was purified by flash chromatography (5%
methanol/dichloromethane) to obtain a white foam (3.5 g, 76%).
LRMS: +ve ion 504 [M+Na], .sup.1H-NMR; .delta. (CDCl.sub.3), 7.35
(5H, s), 6.93 (2H, m), 6.84 (1H, m), 6.01 (2H, s), 5.55 (1H, d,
J=9.5 Hz), 5.06 (2H, m), 4.54 (1H, d, J=9.7 Hz), 3.65 (8H, m), 0.99
(9H, s).
Step B:
2-Amino-1S-[4-(3a,7a-dihydro-benzo[1,3]dioxole-5-carbonyl)-piperaz-
in-1-yl]-3,3-dimethyl-butan-1-one
[0234] To a solution of
{1S-[4-(3a,7a-Dihydro-benzo[1,3]dioxole-5-carbonyl)-piperazine-1-carbonyl-
]-2,2-dimethyl-propyl}-carbamic acid benzyl ester (3.5 g, 7.3 mmol)
in ethanol (70 ml), under a blanket of argon, was added 10%
palladium on charcoal (350 mg). Hydrogen was bubbled through the
suspension for 1 hour and then the reaction was stirred under an
atmosphere of hydrogen for 2 hours. The palladium catalyst was
filtered off and the solvent removed in vacuo to yield a white foam
(2.5 g. 99%). LRMS: +ve ion 348 [M+1], 370 [M+Na], .sup.1H-NMR;
.delta. (CDCl.sub.3), 6.94 (2H, m), 6.84 (1H, m), 6.01 (2H, s),
3.64 (9H, m), 1.61 (2H, s), 0.98 (9H, s).
[0235] The following example 56 was prepared in a similar way to
Example 55 except 3,4 methylenedioxybenzoyl chloride was replaced
with 3-(bromomethyl)pyridine.
Example 56
2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[2,2-dimethyl-1S-(4-pyridin-3-ylmethyl-piperazine-1-carbonyl)-propyl]-ami-
de
##STR00079##
[0237] .sup.1H-NMR; .delta. (CDCl.sub.3, rotamers), 8.62 (2H, m),
8.39 (0.4H, s), 7.82 (0.6H, s), 7.67 (1H, d, J=7.7 Hz), 7.28 (1H,
m), 6.92 (0.4H, m), 6.76 (0.6H, m), 4.91 (1H, m), 4.02 (0.4H, m),
3.82 (3H, m), 3.51 (4.6H, m), 2.84 (0.6H, m), 2.68 (0.4H, m), 2.36
(4H, m), 1.53 (2H, m), 1.25 (4H, m), 0.97 (3H, s), 0.93 (6H, s),
0.88 (3H, t, J=7.0 Hz). .sup.13C-NMR; .delta. (CDCl.sub.3), 175.5,
173.3, 170.3, 170.2, 150.6, 149.1, 147.2, 133.6, 123.9, 66.2, 60.3,
54.8, 54.5, 53.7, 53.5, 53.4, 53.3, 53.1, 52.9, 52.8, 52.5, 48.9,
47.3, 47.1, 46.1, 45.1, 2.5 and 42.4. LRMS: +ve ion 484 [M+Na].
Example 57
N-[1S-(4-Benzo[1,3]dioxol-5-ylmethyl-piperazine-1-carbonyl)-2,2-dimethyl-p-
ropyl]-2R-cyclopentylmethyl-3-(formyl-hydroxy-amino)-propionamide
##STR00080##
[0239] The title compound was prepared as detailed in scheme 1 from
2S-Amino-1-(4-benzo[1,3]dioxol-5-ylmethyl-piperazin-1-yl)-3,3-dimethyl-bu-
tan-1-one (see scheme 3, piperonyl piperazine is commerically
available) and
2R-Cyclopentylmethyl-3-(formyl-hydroxy-amino)-propionic acid
pentafluorophenyl ester.
[0240] .sup.1H-NMR; .delta. (CDCl.sub.3, rotamers), 8.40 (0.4H,
bs), 7.82 (0.6H, bs), 6.83 (1H, bs), 6.76-6.63 (2H, m), 6.58-6.54
(1H, m), 5.94 (2H, s), 4.87 (1H, m), 4.10-3.28 (9H, m), 2.87-2.16
(7H, m), 1.85-1.33 (10H, m); 1.09 (1H, m); 0.98 (3.6H, m); 0.93
(5.4H, m); LRMS: +ve ion 531 [M+H], 553 [M+Na]. -ve ion 529 [M-1];
HPLC: RT=4.91 min, 97% pure.
[0241] Examples 58-67 were prepared by synthetic methods analogous
to those described for Example 55, using the relevant acid chloride
or carboxylic acid in Step A of Scheme 3. The compounds were
synthesised in parallel and purification of the final compounds,
where necessary, was carried out by preparative HPLC.
Characterisation data for these compounds are provided in Table
4.
[0242] Examples 68-79 were prepared by synthetic methods analogous
to those described for Example 43, but using an acid chloride,
carboxylic acid or sulfonyl chloride in place of the bromide in
Step C of Scheme 2. Purification of the final compounds, where
necessary, was carried out by preparative HPLC. Characterisation
data for these compounds are provided in Table 5.
TABLE-US-00006 TABLE 4 ##STR00081## HPLC Reten- HPLC Exam- tion
Purity ple R = Mass Spec. time % 58 ##STR00082## M + Na = 513 4.9
>84 59 ##STR00083## M + Na = 556 5.1 >87 60 ##STR00084## M +
Na = 501 4.8 >84 61 ##STR00085## M + Na = 515 5 >85 62
##STR00086## M + Na = 486 5.1 >83 63 ##STR00087## M + Na = 498
3.8 >95 64 ##STR00088## M + Na = 514 4.4 98 65 ##STR00089## M +
Na = 531 4.5 93 66 ##STR00090## M + Na = 499 7.8 >96 67
##STR00091## M + Na = 502 M - 1 = 478 10.4 92
TABLE-US-00007 TABLE 5 ##STR00092## HPLC Retention HPLC Example R =
Mass Spec. time Purity (%) 68 ##STR00093## M + Na = 503 M - 1 = 479
4.9 100 69 ##STR00094## M + Na = 519 M - 1 = 495 4.9 100 70
##STR00095## M + Na = 516 M - 1 = 492 4.7 96 71 ##STR00096## M + Na
= 488 M - 1 = 464 4.6 99 72 ##STR00097## M + 1 = 559 M + Na = 581 M
- 1 = 557 4.5 >88 73 ##STR00098## M + 1 = 559 M + Na = 581 M - 1
= 557 5.2 100 74 ##STR00099## M + 1 = 510 M + Na = 532 M - 1 = 508
5 >95 75 ##STR00100## M + Na = 532 4.96 99 76 ##STR00101## M + 1
= 476 M + Na = 498 M - 1 = 474 4.77 95 77 ##STR00102## M + 1 = 478
M + Na = 500 M - 1 = 476 5.09 100 78 ##STR00103## M + 1 = 587 M +
Na = 609 M - 1 = 585 6.08 100 79 ##STR00104## M + 1 = 551 M + Na =
573 M - 1 = 549 6.01 97
[0243] The compounds of Examples 58-79 are named as follows:
Example 58
[0244] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
{2,2-dimethyl-1S-[4-(5-methyl-pyrazine-2-carbonyl)-piperazine-1-carbonyl]-
-propyl}-amide
Example 59
[0244] [0245] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(4-acetyl-3,5-dimethyl-H-pyrrole-2-carbonyl)-piperazine-1-carbonyl-
]-2,2-dimethyl-propyl}-amide
Example 60
[0245] [0246] 2R-[(Formyl-hydroxy-amino)-methyl]hexanoic acid
{2,2-dimethyl-1S-[4-(5-methyl-1H-pyrazole-3-carbonyl)-piperazine-1-carbon-
yl]-propyl}-amide
Example 61
[0246] [0247] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(2,5-dimethyl-2-H-pyrazole-3-carbonyl)-piperazine-1-carbonyl]-2,2--
dimethyl-propyl}-amide
Example 62
[0247] [0248] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
{2,2-dimethyl-1S-[4-(1-H-pyrrole-2-carbonyl)-piperazine-1-carbonyl]-propy-
l}-amide
Example 63
[0248] [0249] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
{2,2-dimethyl-1
S-[4-(pyridine-3-carbonyl)-piperazine-1-carbonyl]-propyl}-amide
Example 64
[0249] [0250] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(2-hydroxy-pyridine-3-carbonyl)-piperazine-1-carbonyl]-2,2-dimethy-
l-propyl}-amide
Example 65
[0250] [0251] 2R[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(2,6-dihydroxy-pyrimidine-4-carbonyl)-piperazine-1-carbonyl]-2,2-d-
imethyl-propyl}-amide
Example 66
[0251] [0252] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
{2,2-dimethyl-1S-[4-(pyrazine-2-carbonyl)-piperazine-1-carbonyl]-propyl}--
amide
Example 67
[0252] [0253] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
{2,2-dimethyl-1S-[4-(5-methyl-isoxazole-3-carbonyl)-piperazine-1-carbonyl-
]-propyl}-amide
Example 68
[0253] [0254] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{2,2-dimethyl-1
S-[4-(thiophene-2-carbonyl)-piperazine-1-carbonyl]-propyl}-amide
Example 69
[0254] [0255] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{2,2-dimethyl-1S-[4-(4-methyl-[1,2,3]thiadiazole-5-carbonyl)-piperazine-1-
-carbonyl]-propyl}-amide
Example 70
[0255] [0256] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(3,5-dimethyl-isoxazole-4-carbonyl)-piperazine-1-carbonyl]-2,2-dim-
ethyl-propyl}-amide
Example 71
[0256] [0257] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
{1S-[4-(isoxazole-5-carbonyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}-
-amide
Example 72
[0257] [0258] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
{2,2-dimethyl-1S-[4-(2-pyridin-4-yl-thiazole-4-carbonyl)-piperazine-1-car-
bonyl]-propyl}-amide
Example 73
[0258] [0259] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(5-methanesulfonyl-thiophene-2-carbonyl)-piperazine-1-carbonyl]-2,-
2-dimethyl-propyl}-amide
Example 74
[0259] [0260] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(2,4-dimethyl-thiazole-5-carbonyl)-piperazine-1-carbonyl]-2,2-dime-
thyl-propyl}-amide
Example 75
[0260] [0261] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(2-chloro-pyridine-3-carbonyl)-piperazine-1-carbonyl]-2,2-dimethyl-
-propyl}-amide
Example 76
[0261] [0262] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{2,2-dimethyl-1S-[4-(pyridine-2-carbonyl)-piperazine-1-carbonyl]-propyl}--
amide
Example 77
[0262] [0263] 2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
{2,2-dimethyl-1S-[4-(1-methyl-1-H-pyrrole-2-carbonyl)-piperazine-1-carbon-
yl]-propyl}-amide
Example 78
[0263] [0264] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(biphenyl-4-sulfonyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}--
amide
Example 79
[0264] [0265] 2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
{1S-[4-(biphenyl-4-carbonyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl}--
amide
[0266] Examples 80 and 81 were prepared in a similar manner to
Example 43 from
2R-[(Benzyloxy-formyl-amino)-methyl]-3-cyclopentyl-propionic
acid.
Example 80
2R-[(Formyl-hydroxy-amino)-methyl]hexanoic acid
{2,2-dimethyl-1S-{4-[4-(morpholine-4-carbonyl)-benzyl]-piperazine-1-carbo-
nyl}-propyl}-amide
##STR00105##
[0268] .sup.1H-NMR; .delta. (CDCl.sub.3, rotamers), 8.38 (0.4H, s),
7.81 (0.6H, s), 7.36 (4H, s), 6.77 (0.4H, d, J=8.9 Hz), 6.62 (0.6H,
d, J=9.3 Hz), 4.88 (1H, m), 4.03 (0.4H, dd, J=14.6, 7.1 Hz), 3.91
(1H, m), 3.76 (8H, m), 3.51 (5.6H, m), 3.38 (1H, m), 2.84 (0.6H,
m), 2.69 (0.4H, m), 2.55 (2H, m), 2.30 (2H, m), 1.57 (9H, m), 1.05
(2H, m), 0.98 (3H, s), 0.94 (6H, s). .sup.13C-NMR; .delta.
(CDCl.sub.3, rotamers), 176.0, 173.3, 170.7, 170.1, 156.5, 140.2,
134.8, 129.5, 127.7, 67.3, 62.8, 55.0, 54.5, 53.8, 53.6, 53.2,
53.1, 52.2, 49.0, 47.4, 47.2, 46.0, 44.9, 42.7, 42.4, 38.5, 38.2,
36.9, 36.7, 35.9, 33.2, 27.0, 25.6 and 25.5. LRMS: +ve ion 600
[M+H], 622 [M+Na]. HPLC: RT=4.63 min, 100% pure.
Example 81
2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[2,2-dimethyl-1S-(4-pyridin-3-ylmethyl-piperazine-1-carbonyl)-propyl]-ami-
de
##STR00106##
[0270] .sup.1H-NMR; 5 (CDCl.sub.3, rotamers), 8.53 (2H, m), 8.40
(0.3H, s), 7.81 (0.7H, s), 7.65 (1H, d, J=7.7 Hz), 7.27 (1H, m),
6.76 (0.3H, d, J=8.8 Hz), 6.67 (0.7H, d, J=8.9 Hz), 4.89 (1H, m),
4.03 (0.3H, m), 3.92 (1H, m0, 3.77 (1.7H, m) 3.47 (5H, m), 2.86
(0.7H, m), 2.69 (0.3H, m), 2.56 (2H, m0, 2.31 (2H, m), 1.64 (9H,
m), 1.07 (2H, m), 0.98 (3H, s), 0.93 (6H, s). .sup.13C-NMR; .delta.
(CDCl.sub.3, rotamers), 175.5, 173.0, 169.8, 150.3, 148.8, 136.7,
133.1, 123.4, 60.0, 54.6, 54.1, 53.4, 53.2, 52.8, 52.7, 52.1, 48.7,
46.9, 46.8, 45.6, 44.5, 42.2, 42.0, 38.2, 37.9, 36.5, 36.3, 5.6,
32.8, 32.7, 6.7, 25.3 and 25.2. LRMS: +ve ion 488 [M+H], 510
[M+Na]. HPLC: RT=4.48 min, 98% pure.
Example 82
2R-[(Formyl-hydroxy-amino)methyl]-hexanoic acid
{1S-[4-(4-hydroxymethyl-phenyl)-piperazine-1-carbonyl]-2,2-dimethyl-propy-
l}-amide
##STR00107##
[0272] LRMS: +ve ion 485 [M-OH].sup.+, -ve ion 501 [M-H]. HPLC
RT=5.8 min, 95% pure.
[0273] The title compound was prepared from
3-(Benzyloxy-formyl-amino)-2R-cyclopentylmethyl-propionic acid
pentafluoro-phenyl ester and 4-(4-Benzyl-piperazin-1-yl)-benzoic
acid ethyl ester which is a known literature compound.
{1-[4-(4-Hydroxymethyl-phenyl)-piperazine-1-carbonyl]-2,2-dimethyl-propyl-
}-carbamic acid benzyl ester (Scheme 4) was deprotected and coupled
to the pentafluorophenyl ester in a manner identical to that in
Scheme 1.
##STR00108##
Step A [4-(4-Benzyl-piperazin-1-yl)-phenyl]-methanol
[0274] To a solution of lithium aluminium hydride (88 mg, 2.3 mmol)
in dry THF (20 ml) was added 4-(4-Benzyl-piperazin-1-yl)-benzoic
acid ethyl ester (500 mg, 1.5 mmol). The suspension was stirred at
75.degree. C. for 4 h. The reaction mixture was allowed to cool and
a few drops of water were added followed by 1-2 drops of 1M sodium
hydroxide. A white precipitate formed and was filtered off, the THF
was removed in vacuo, and brine (10 ml) was added to the residue.
This mixture was washed with ether (2.times.50 ml, the ether layers
were combined and dried over anhydrous magnesium sulphate and the
solvent removed in vacuo to yield a yellow solid (405 mg). Flash
chromatography (3% MeOH/CH.sub.2Cl.sub.2) allowed the isolation of
the title compound as a white solid (331 mg, 76%). .sup.1H-NMR
.delta. (CDCl.sub.3) 7.38-7.21 (7H, m, ArH), 6.91-6.85 (2H, m,
ArH), 4.59 (2H, s), 3.57 (2H, s), 3.21-3.17 (4H, m), 2.61-2.58 (4H,
m). HPLC: 2.4 min (99% @ 214 nm); LRMS +ve: 283 (M+1, 80).
Step B: (4-piperazin-1-yl-phenyl)-methanol
[0275] To a solution of
[4-(4-Benzyl-piperazin-1-yl)-phenyl]-methanol in EtOH (50 ml) under
a blanket of argon was added a suspension of 10% palladium on
charcoal (1.5 g) in EtOH (150 ml). Hydrogen was bubbled through the
suspension for 1 h and then the reaction mixture was stirred under
a blanket of hydrogen for 60 h at RT. The catalyst was filtered off
and the solvent removed in vacuo to yield the title compound as a
white solid (4.8 g, 100%). .sup.1H-NMR .delta. (CDCl.sub.3)
7.30-7.21 (2H, m, ArH), 6.94-6.88 (2H, m, ArH), 4.59 (2H, s),
3.18-2.98 (8H, m). HPLC: 0.5 min (37% @ 214 nm), 0.7 min (55% @ 214
nm), multiple peaks due to salt formation from TFA buffer, LRMS
+ve: 193 (M+1, 70).
Step C:
{1-[4-(4-Hydroxymethyl-phenyl)-piperazine-1-carbonyl]-2,2-dimethyl-
-propyl}-carbamic acid benzyl ester
[0276] To a solution of CBz protected tert-leucine (7.4 g, 28 mmol)
in dichloromethane (20 ml) was added
(4-piperazin-1-yl-phenyl)-methanol in a solution of
DMF/dichloromethane (50:50, 250 ml). EDC (7.3 g, 38 mmol), HOAt
(0.34 g, 2.5 mmol) and triethylamine (7.0 ml, 50 mmol) were
subsequently added. The reaction mixture was stirred at RT for 18
h. The solvent was removed in vacuo to yield a yellow oil, which
was taken up in dichloromethane (300 ml) and was washed with 1M
sodium carbonate (2.times.200 ml), 1M hydrochloric acid
(1.times.200 ml), brine (1.times.200 ml) dried (anhydrous magnesium
sulphate) and the solvent removed in vacuo to yield a white foam
(11.8 g). Flash chromatography 2% MeOH/dichloromethane allowed the
isolation of the title compound as a white foam (7.01 g, 63%). HPLC
5.7 min (100% @ 214 nm). LRMS +ve 462 (M+Na, 60), 440 (M+1, 20),
422 (M-OH, 100).
Example 83
2R-[(Formyl-hydroxy-amino)-methyl]-hexanoic acid
[2,2-dimethyl-1S-(4-pyrimidin-2-yl-piperazine-1-carbonyl)-propyl]-amide
##STR00109##
[0278] Prepared by method analogous to Example 82.
[0279] .sup.1H-NMR; .delta. (CDCl.sub.3), 8.40 (0.3H, s), 8.33 (2H,
d, J=4.8 Hz), 7.82 (0.7H, s), 6.76 (1H, d, J=8.4 Hz), 6.55 (1H, t,
J=4.7 Hz), 4.94 (1H, m), 4.09-3.37 (10H, m), 2.86-2.78 (0.7H, m),
2.72-2.65 (0.3H, m,) 1.63-1.18 (6H, m), 1.02 (3H, s), 0.97 (6H, s),
0.85 (3H, m). .sup.13C-NMR; .delta. (CDCl.sub.3), 176.0, 173.3,
170.5, 161.9, 158.2, 111.1, 55.3, 54.7, 52.1, 48.7, 47.1, 47.0,
46.5, 45.1, 44.3, 44.2, 44.0, 43.9, 42.6, 42.4, 35.9, 30.3, 30.2,
29.7, 29.6, 27.1, 22.9 and 14.3. LRMS: +ve ion 449 [M+H], 471
[M+Na], -ve ion 447 [M-H]. HPLC: RT=4.99 min, 100% pure.
Example 84
N.sup.1-{1S-[4-(Benzo[1,3]dioxole-5-carbonyl)-piperazine-1-carbonyl]-2,2-d-
imethyl-propyl}-2R-cyclopentylmethyl-N.sup.4-hydroxy-succinamide
##STR00110##
[0281] Example 84 was prepared as detailed below (see Scheme 5)
from 2R-Cyclopentylmethyl-succinic acid 4-tert-butyl ester,
prepared by analogous methods described in patent WO 92/13831, and
2-Amino-1S-[4-(benzo[1,3]dioxole-5-carbonyl)-piperazin-1-yl]-3,3-dimethyl-
-butan-1-one, prepared by methods described in Scheme 3.
##STR00111##
Step A: 2R-Cyclopentylmethyl-succinic acid 1-benzyl ester
[0282] To a solution of 2R-Cyclopentylmethyl-succinic acid
4-tert-butyl ester (960 mg, 2.7 mmol) in dichloromethane (30 ml),
was added TFA (30 ml). The reaction mixture was left at -4.degree.
C. for 18 h. The solvent was removed in vacuo and the TFA
co-evaporated with toluene and ether in vacuo to yield a yellow oil
(810 mg, 100%). .sup.1H-NMR .delta. (CDCl.sub.3), 7.38-7.29 (5H,
m), 5.15 (2H, s), 2.93-2.87 (1H, m), 2.78 (1H, dd, J.sub.1=9.485
J.sub.2=16.81), 2.52 (1H, dd, J.sub.1=4.92 J.sub.2=17.01),
1.84-1.63 (3H, m), 1.62-1.53 (2H, m), 1.52-1.40 (3H, m), 1.09-1.02
(2H, m).
Step B: 2R-Cyclopentylmethyl-N-(1-isobutoxy-ethoxy)-succinamic acid
benzyl ester
[0283] To a solution of 2R-Cyclopentylmethyl-succinic acid 1-benzyl
ester (810 mg, 2.8 mmol) in DMF, was added EDC (805 mg, 4.2 mmol),
HOAt, (10% w/w) and O-(1-Isobutoxy-ethyl)-hydroxylamine (745 mg,
5.6 mmol). The reaction was left stirring for 60 h at room
temperature. The solvent was removed in vacuo, the residue was
taken up in ethyl acetate and washed successively with 1M
hydrochloric acid, 1M sodium carbonate and saturated sodium
chloride solution. The organic phase was dried over anhydrous
magnesium sulfate and concentrated in vacuo to yield a yellow oil
(1.07 g, 97%).
[0284] .sup.1H NMR; .delta. (CDCl.sub.3), 8.05 (1H, bs), 7.34-7.27
(5H, m), 5.17:5.10 (2H, AB q, J=12.36), 4.92-4.88 (1H, m), 3.52
(1H, dd, J.sub.1=6.643 J.sub.2=9.340), 3.271 (1H, dd, J.sub.1=6.734
J.sub.2=9.267), 3.06-2.95 (1H, m), 2.52-2.23 (2H, m), 1.89-1.41
(11H, m), 1.36 (3H, dd, J.sub.1=3.53 J.sub.2=5.303), 1.06 (2H, bs),
0.919 (6H, d, 6.63).
[0285] ESMS; +ve ion 428 [M+Na]
Step C: 2R-Cyclopentylmethyl-N-(1-isobutoxy-ethoxy)-succinamic
acid
[0286] To a solution of
2R-Cyclopentylmethyl-N-(1-isobutoxy-ethoxy)-succinamic acid benzyl
ester (925 mg, 2.3 mmol) in ethanol, under a blanket of argon, was
added palladium on charcoal (10% w/w). Hydrogen was bubbled through
the suspension for 30 minutes and the reaction stirred under an
atmosphere of hydrogen for 3 hours. The palladium catalyst was
filtered off and the solvent removed in vacuo to yield a yellow oil
(720 mg, 100%).
[0287] .sup.1H-NMR; .delta. (CDCl.sub.3), 4.93 (1H, m), 3.559 (1H,
dd, J.sub.1=6.620 J.sub.2=9.292), 3.292 (1H, dd, J.sub.1=6.70
J.sub.2=9.330), 2.94 (1H, m), 2.49-2.29 (2H, m), 1.93-1.75 (5H, m),
1.61-1.44 (6H, m), 1.377 (3H, dd, J.sub.1=1.237 J.sub.2 5.237),
1.08 (2H, m), 0.919 (6H, d, J.sub.1=6.65).
[0288] ESMS; +ve ion 338 [M+Na], -ve ion 314 [M-1]
Step D:
N.sup.1-{1S-[4-(Benzo[1,3]dioxole-5-carbonyl)-piperazine-1-carbony-
l]-2,2-dimethyl-propyl}-2R-cyclopentylmethyl-N.sup.4-(1-isobutoxy-ethoxy)--
succinamide
[0289] To a solution of
2R-Cyclopentylmethyl-N-(1-isobutoxy-ethoxy)-succinamic acid (150
mg, 0.48 mmol) in DMF (7.5 ml), was added
2-Amino-1S-[4-(benzo[1,3]dioxole-5-carbonyl)-piperazin-1-yl]-3,3-dimethyl-
-butan-1-one (165 mg, 0.5 mmol) and stirred for 5 minutes. EDC (96
mg, 0.5 mmol) was added and the reaction mixture stirred at room
temperature over the weekend. The solvent was removed in vacuo and
the residue taken up in ethyl acetate and washed successively with
1M hydrochloric acid, 1M sodium carbonate and saturated sodium
chloride solution. The organic phase was dried over anhydrous
magnesium sulfate and concentrated in vacuo to yield an `off white`
solid (227 mg, 74%).
[0290] .sup.1H-NMR; .delta. (CDCl.sub.3), 6.87 (2H, m), 6.01 (2H,
s), 4.873 (1H, m), 3.94-3.67 (4H, m), 3.64-3.23 (10H, m), 2.773
(1H, m), 2.43-2.19 (2H, m), 1.89-1.39 (14H, m), 1.357 (3H, dd,
J.sub.1=2.350 J.sub.2=5.306), 1.117 (2H, m), 0.987 (9H, s), 0.913
(6H, d, J.sub.1=6.66). ESMS; +ve ion 667 [M+Na]
Step E:
N.sup.1-{1S-[4-(Benzo[1,3]-dioxole-5-carbonyl)-piperazine-1-carbon-
yl]-2,2-dimethyl-propyl}-2R-cyclopentylmethyl-N.sup.4-hydroxy-succinamide
[0291]
N.sup.1-{1S-[4-(Benzo[1,3]-dioxole-5-carbonyl)-piperazine-1-carbony-
l]-2,2-dimethyl-propyl}-2R-cyclopentylmethyl-N.sup.4-hydroxy-succinamide
(198 mg, 0.31 mmol) was dissolved in a 50/50 mixture of methanol
and 1M hydrochloric acid (16 ml) and stirred at room temperature
for 30 minutes. Pre-washed Amberlyst resin 95 was added until pH 7
was reached and was then filtered under suction and washed with
methanol. The filtrate was concentrated in vacuo with ethanol to
yield a yellowish solid that was purified by preparative HPLC to
yield the title compound as a white foam (62 mg). .sup.1H-NMR;
.delta. (MeOD), 6.935 (1H, s), 6.926 (2H, dd, J.sub.1=7.854
J.sub.2=34.375), 6.018 (2H, s), 4.863 (1H, s), 3.902-3.384 (8H, m),
2.893 (1H, m), 2.323 (1H, dd, J.sub.1=7.86 J.sub.2=14.31), 2.193
(1H, dd, J.sub.1=6.23 J.sub.2=14.39), 1.824 (1H, m), 1.645 (5H, m),
1.491 (2H, m), 1.374 (1H, m), 1.033 (11H, m); .sup.13C-NMR; 8
(MeOD), 177.7, 172.8, 172.2, 171.0, 151.3, 149.7, 130.2, 123.3,
109.7, 103.5, 56.5, 48.1, 43.6, 43.4, 40.1, 39.8, 37.4, 36.4, 34.0,
27.5, 26.5; ESMS; +ve ion 567 [M+Na], -ve ion 543 [M-1]
Preparative Example A
2R-Cyclopentylmethyl-N.sup.1-{2,2-dimethyl-1S-[4-(4-methyl-benzyl)-piperaz-
ine-1-carbonyl]-propyl}-N.sup.4-hydroxy-succinamide
##STR00112##
[0293] The title compound was prepared as detailed below (see
scheme 6) from
2-Cyclopentylmethyl-N-(1-isobutoxy-ethoxy)-succinamic acid (scheme
5).
##STR00113##
Step A:
4-{2S-[2R-Cyclopentylmethyl-3-(1-isobutoxy-ethoxycarbamoyl)-propi-
onylamino]-3,3-dimethyl-butyryl}-piperazine-1-carboxylic acid
benzyl ester
[0294] To a cold (0.degree. C.) solution of the acid (6.8 g, 16.1
mmol) in dichloromethane (80 ml), the hydrochloride salt of the
amine (8.65 g, 19.4 mmol) was added followed by triethylamine (2.92
ml, 21 mmol) and then WSC (3.72 g, 19.4 mmol). The reaction mixture
was stirred overnight allowing the temperature to come back to room
temperature. The reaction mixture was then diluted with
dichloromethane and washed with water (80 ml), with
Na.sub.2CO.sub.3 and brine. The combined organic layer was dried
over MgSO.sub.4 and the solvent was removed in vacuo to yield a
yellowish foam which was purified through flash chromatography to
give a 100% pure compound (8 g, 79% yield).
[0295] .sup.1H-NMR; .delta. (CDCl.sub.3), 8.20 (1H, m), 7.32 (5H,
m), 6.45 (1H, m), 5.11 (2H, s), 4.91-4.82 (21-1, m), 3.87-3.21
(12H, m), 2.41 (1H, m), 2.73 (1H, m), 1.90-1.40 (14H, m), 1.36 (3H,
m), 0.98 (9H, s), 0.90 (6H, d)
Step B:
2R-Cyclopentylmethyl-N.sup.1-[2,2-dimethyl-1S-(piperazine-1-carbon-
yl)-propyl]-N.sup.4-(1-isobutoxy-ethoxy)-succinamide
[0296] To a suspension of the Z-protected piperazine (8 g, 12.7
mmol) in MeOH (100 ml) was added Pd/C (0.8 g) and then H.sub.2 was
bubbled for 1 h. The reaction mixture was then stirred under a
blanket of H.sub.2 for another hour. Pd/C was filtered off through
a celite pad to give the desired compound in a 99% yield.
[0297] ESMS; +ve ion 498 [M+1], -ve ion 496 [M-1]; HPLC: RT=5.21
min
Step C:
2R-Cyclopentylmethyl-N.sup.1-{2,2-dimethyl-1S-[4-(4-methyl-benzyl)-
-piperazine-1-carbonyl]-propyl}-N.sup.4-(1-isobutoxy-ethoxy)-succinamide
[0298] To a solution of 4-methyl benzyl bromide (74 mg, 0.4 mmol)
in dichloromethane (2 ml) were added a solution of the piperazine
in dichloromethane (1.2 ml, 0.33 mmol) and Net.sub.3 (60 ml, 0.4
mmol). The reaction mixture was stirred at room temperature for 12
hours. Water was added (1.5 ml) and the resulting solution filtered
through polypropylene hydrophobic cartridges (1 PS filter). The
solvent was then removed under reduced pressure to afford the
expected adduct.
Step D:
2R-Cyclopentylmethyl-N.sub.1-{2,2-dimethyl-1S-[4-(4-methyl-benzyl)-
-piperazine-1-carbonyl]-propyl}-hydroxy-succinamide
[0299] To a solution of the latter in MeOH (4 ml) was added HCl 1N
(600 ml) and the reaction mixture was stirred for 2 h. Then 60 ml
of NEt.sub.3 were added and the solvent was removed under reduced
pressure. The crude reaction mixture was purified through HPLC.
[0300] The compounds of Examples 85-87 were prepared by the
synthetic route outlined in Scheme 5 and as described in detail for
Preparative Example A. Step C and Step D were carried out in
parallel format for all examples. Characterisation data for the
compounds are provided in Table 6.
TABLE-US-00008 TABLE 6 ##STR00114## Retention Exam- Mass Time ple
Structures Spec (min) 85 ##STR00115## M + 1 = 563 M - 1 = 561 5.2
86 ##STR00116## M + 1 = 537 M - 1 = 535 5.03 87 ##STR00117## M + 1
= 488 M - 1 = 486 4.17
[0301] The compounds of Examples 85-87 are named as follows:
Example 85
[0302]
N.sup.1-[1S-(4-Biphenyl-4-ylmethyl-piperazine-1-carbonyl)-2,2-dim-
ethyl-propyl]-2R-cyclopentylmethyl-N.sup.4-hydroxy-succinamide
Example 86
[0302] [0303]
2R-Cyclopentylmethyl-N.sup.1-[2,2-dimethyl-1S-(4-naphthalen-2-ylmethyl-pi-
perazine-1-carbonyl)-propyl]-N.sup.4-hydroxy-succinamide
Example 87
[0303] [0304]
2R-Cyclopentylmethyl-N.sup.1-[2,2-dimethyl-1S-(4-pyridin-3-ylmethyl-piper-
azine-1-carbonyl)-propyl]-N.sup.4-hydroxy-succinamide
Example 88
4-(1-{2S-[3-(Benzyloxy-formyl-amino)-2R-cyclopentylmethyl-propionylamino]--
3,3-dimethyl-butyryl}-piperidin-4-yloxy)-N,N-dimethyl benzamide
##STR00118##
[0306] The title compound was prepared as detailed below (see
scheme 8) from the
3-(Benzyloxy-formyl-amino)-2R-cyclopentylmethyl-propionic acid
pentafluorophenyl ester and
4-[1-(2S-Benzyloxycarbonylamino-3,3-dimethyl-butyryl)-piperidin-4-yloxy]--
benzoic acid methyl ester (see scheme 7).
##STR00119##
Step A:
[1S-(4-Hydroxy-piperidine-1-carbonyl)-2,2-dimethyl-propyl]carbami-
c acid benzyl ester
[0307] To a cold solution (0.degree. C.) of the Z-tert-leucine
(3.48 g, 13.1 mmol) and 4-hydroxy piperidine (1.4 g, 13.7 mmol) in
CH.sub.2Cl.sub.2 (40 ml) were added WSC (2.75 g, 14.4 g) followed
by HOAt (18 mg, 0.13 mmol). The reaction mixture was stirred at
room temperature for 12 hours and then washed with water and brine.
The combined organic layer was dried over MgSO.sub.4 and the
solvent removed under reduced pressure to furnish a yellow oil
which was purified through flash chromatography. The desired
compound was obtained in 64% yield.
[0308] .sup.1H NMR; .delta. (CDCl.sub.3), 7.34 (5H, s), 5.58 (1H,
m), 5.08 (2H, m), 4.60 (1H, m), 3.91 (3H, m), 3.49-3.05 (2H, m),
1.91 (4H, m), 0.98 (9H, d, J=3.57); ESMS; +ve ion 371 [M+Na]; HPLC:
RT=5.44 min.
Step B:
4-[1-(2S-Benzyloxycarbonylamino-3,3-dimethyl-butyryl)-piperidin-4--
yloxy]-benzoic acid methyl ester
[0309] To a cold solution (0.degree. C.) of the latter compound
(1.45 g, 4.2 mmol), 4-hydroxy methyl benzoate (0.7 g, 4.6 mmol) and
triphenylphosphine (1.48 g, 5.46 mmol) were added dropwise followed
by the addition of DEAD (0.86 ml, 5.46 mmol). The reaction mixture
was stirred at 0.degree. C. for 2.5 hours. Thf was removed in vacuo
and the crude residue was taken-up in ethyl acetate. The organic
layer was washed with water and brine and subsequently dried over
MgSO.sub.4. After purification through flash chromatography the
expected compound was obtained as a pure white foam in 70%
yield.
[0310] .sup.1H NMR; .delta. (CDCl.sub.3), 7.99 (2H, dd,
J.sub.1=1.23 J.sub.2=8.82), 7.35 (5H, m), 6.92 (2H, dd, 4=1.18
J.sub.2=8.76), 5.58 (1H, m), 5.09 (2H, m), 4.62 (2H, m), 3.89 (4H,
m), 3.72 (1H, m), 3.61 (2H, m), 1.90 (4H, m), 0.99 (914, s); ESMS;
+ve ion 505 [M+Na]; HPLC: RT=6.73 min.
Step C:
4-[1S-(2-Amino-3,3-dimethyl-butyryl)-piperidin-4-yloxy]benzoic acid
methyl ester
[0311] To a solution of the latter compound (650 mg, 1.35 mmol) in
EtOH (10 ml) was added Pd/C (65 mg) and H.sub.2 was bubbled through
the resulting suspension for 4 hours. Pd/C was then removed by
filtration through a celite pad. The solvent was removed under
reduced pressure to give the desired compound in quantitative
yield.
[0312] .sup.1H NMR; .delta. (CDCl.sub.3), 7.99 (2H, d, J=8.82),
6.92 (2H, d, J=8.47), 4.65 (111, m), 3.89 (3H, s), 3.72 (2H, m),
3.56 (1H, d, J=4.82), 1.95 (4H, m), 0.99 (9H, s); ESMS; +ve ion 349
[M+1].
##STR00120##
Step A:
4-(1-[{2S-[3-(Benzyloxy-formyl-amino)-2R-cyclopentylmethyl-propio-
nylamino]-3,3-dimethyl-butyryl}-piperidin-4-yloxy)-benzoic acid
methyl ester
[0313] To a solution of the amine (3.4 g, 9.70 mmol) in DMF were
added the PFP ester (4 g, 8.50 mmol) followed by NEt.sub.3 (1.3 ml,
9.34 mmol). The reaction mixture was stirred overnight at room
temperature. The solvent was removed under reduced pressure and the
crude dissolved in ethyl acetate. The work-up was made by means of
water, sodium carbonate, ammonium chloride and brine. The combined
organic layer was dried over MgSO.sub.4 and the solvent removed
under reduced pressure to yield a foam. The crude product was
purified through flash chromatography to yield the desired compound
as a white foam in 98% yield.
[0314] .sup.1H-NMR; .delta. (CDCl.sub.3, rotamers), 8.01-7.96 (2H,
m), 7.38 (5H, bs), 6.93-6.88 (2H, m), 6.32-6.29 (1H, m), 5.01-4.52
(7H, m), 4.02-3.52 (7H, m), 3.89 (3H, s), 2.68-2.50 (1H, m),
1.98-1.34 (15H, m), 0.95 (9H, s); LRMS: +ve ion 436 [M+H], 658
[M+Na]. HPLC: RT=6.79 min, 98% pure.
Step B:
4-{1-[2S-(3-Benzyloxyamino-2R-cyclopentylmethyl-propionylamino)-3,-
3-dimethyl-butyryl]-piperidin-4-yloxy}-benzoic acid
[0315] To a cold solution (0.degree. C.) of the latter compound
(100 mg, 0.16 mmol) in a mixture of THF/MeOH/H.sub.2O (3:1:1; 2.5
ml) was added LiOH (33 mg). The reaction mixture was stirred for 48
hours at room temperature. The solvent was removed under vacuo and
the crude dissolved in water. The aqueous layer was extracted by
means of Et.sub.2O and then acidified to pH=1 by means of HCl 1N.
The desired product was then extracted from Et.sub.2O. The organic
layer was dried over MgSO.sub.4 and the solvent removed under
reduced pressure to yield the desired compound as a white solid in
61% yield.
[0316] .sup.1H-NMR; 5 (CDCl.sub.3, rotamers), 8.06-8.01 (2H, m),
7.38-7.30 (5H, m), 7.09-6.99 (1H, 2d, J=9.3 Hz), 6.94-6.89 (2H, m),
5.02 (1H, d, J=9.4 Hz), 4.75 (2H, s), 4.69-4.61 (1H, m), 4.08-3.67
(4H, m), 3.58-3.42 (2H, m), 3.17-3.01 (2H, m), 2.62 (1H, m),
2.10-1.40 (15H, m), 1.01 (9H, s); LRMS: +ve ion 594 [M+H], -ve ion
592 [M-1]. HPLC: RT=5.92 min, 98% pure.
Step C:
4-(1-{2S-[3-(Benzyloxy-formyl-amino)-2R-cyclopentylmethyl-propiony-
lamino]-3,3-dimethyl-butyryl}-piperidin-4-yloxy)-benzoic acid
[0317] To a cold (0.degree. C.) of the acid (4.8 g, 8.1 mmol) in
THF (100 ml) were added the mixed anhydride (1.8 g, 20.3 mmol) and
NEt.sub.3 (3.33 ml, 24.3 mmol). The reaction mixture was stirred at
room temperature for 12 hours. The solvent was then removed under
reduced pressure and the residue was dissolved in CH.sub.2Cl.sub.2.
The organic layer was washed with water and brine and dried over
MgSO.sub.4. The solvent was removed in vacuo to yield the desired
derivative.
[0318] .sup.1H-NMR; .delta. (CDCl.sub.3, rotamers), 8.19-7.89 (3H,
bs), 7.46-7.30 (5H, m), 7.02-6.85 (1H, m), 5.02-4.53 (4H, m),
4.04-3.37 (6H, m), 2.70 (1H, m), 1.98-1.35 (15H, m), 0.97 (9H, s);
LRMS: +ve ion 644 [M+Na], -ve ion 620 [M-1] HPLC: RT=6.29 min, 95%
pure.
Step D:
4-(1-{2S-[3-(Benzyloxy-formyl-amino)-2R-cyclopentylmethyl-propiony-
lamino]-3,3-dimethyl-butyryl}-piperidin-4-yloxy)-N,N-dimethyl-benzamide
[0319] To a cold (0.degree. C.) solution of the starting acid (0.35
g, 0.56 mmol) in CH.sub.2Cl.sub.2 (8 ml) were added dimethyl amine
(0.67 mmol), WSC (118 mg, 0.61 mmol) and HOAt (8 mg, 0.06 mmol).
The reaction mixture was stirred at room temperature for 12 hours.
Water was added (3 ml) and the resulting solution filtered through
polypropylene hydrophobic cartridges (1 PS filter). The solvent was
then removed under reduced pressure to afford the expected adduct.
The crude compound was then purified through flash chromatography
to afford a 100% pure compound with a 55% yield.
[0320] LRMS: +ve ion 671 [M+Na], HPLC: RT=6.32 min, 100% pure.
Step E:
4-(1S-{2-[2R-Cyclopentylmethyl-3-(formyl-hydroxy-amino)-propionyla-
mino]-3,3-dimethyl-butyryl}-piperidin-4-yloxy)-N,N-dimethyl-benzamide
[0321] To a solution of the latter compound (200 mg, 0.31 mmol)
were added cyclohexene (0.5 ml) and Pd/C (24 mg). The reaction
mixture was stirred to reflux for 3 h. Pd/C was then filtered off
through a celite pad. The solvent was removed under reduced
pressure to afford the desired adduct as a pure compound. LRMS: +ve
ion 581 [M+Na], HPLC: RT=5.49 min, 100% pure.
[0322] The compounds of Examples 88a-93 were prepared by the
synthetic route outlined in Scheme 9 and as described in detail for
Example 88. Step C and Step D were carried out in parallel format
for all examples. Characterisation data for the compounds are
provided in Table 7.
TABLE-US-00009 TABLE 7 Mass Spectral HPLC Example Structure Data RT
(min) 88 ##STR00121## 581 (M + Na), 559 (M + 1), 557 (M - 1). 5.5
.sup. 88a ##STR00122## 545 (M + Na), 567 (M + 1), 543 (M - 1). 5.3
89 ##STR00123## 601 (M + Na), 623 (M + 1), 599 (M - 1). 5.4 90
##STR00124## 614 (M + Na), 636 (M + 1), 612 (M - 1). 4.8 91
##STR00125## 615 (M + Na), 637 (M + 1), 613 (M - 1). 5.2 92
##STR00126## 615 (M + Na), 637 (M + 1), 613 (M - 1). 5.4
[0323] The compounds of Examples 88a-93 are named as follows:
Example 88a
[0324]
4-(1-{2S-[3-(Benzyloxy-formyl-amino)-2R-cyclopentylmethyl-propion-
ylamino]-3,3-dimethyl-butyryl}-piperidin-4-yloxy)-N-methyl
benzamide
Example 89
[0324] [0325]
2R-Cyclopentylmethyl-N-(2,2-dimethyl-1S-{4-[4-(morpholine-4-carbonyl)-phe-
noxy]-piperidine-1-carbonyl}-propyl)-3-(formyl-hydroxy-amino)-propionamide-
.
Example 90
[0325] [0326]
2R-Cyclopentylmethyl-N-(2,2-dimethyl-1S-{4-[4-(4-methyl-piperazine-1-carb-
onyl)-phenoxy]-piperidine-1-carbonyl}-propyl)-3-(formyl-hydroxy-amino)-pro-
pionamide.
Example 91
[0326] [0327]
2R-Cyclopentylmethyl-3-(formyl-hydroxy-amino)-N-(1S-{4-[4-(4-hydroxy-pipe-
ridine-1-carbonyl)-phenoxy]piperidine-1-carbonyl}-2,2-dimethyl-propyl)-pro-
pionamide.
Example 92
[0327] [0328]
2R-Cyclopentylmethyl-3-(formyl-hydroxy-amino)-N-(1S-{4-[4-(2S-hydroxymeth-
yl-pyrrolidine-1-carbonyl)-phenoxy]-piperidine-1-carbonyl}-2,2-dimethyl-pr-
opyl)-propionamide.
Example 93
[0328] [0329]
4-(1-{2S-[2R-Cyclopentylmethyl-3-(formyl-hydroxy-amino)-propionylamino]-3-
,3-dimethyl-butyryl}-piperidin-4-yloxy)-benzoic acid
Example 94
4-(1-{2S-[2R-Cyclopentylmethyl-3-(formyl-hydroxy-amino)-propionylamino]-3,-
3-dimethyl-butyryl}-piperidin-4-yloxy)-benzoic acid methyl
ester
##STR00127##
[0331] The title compound was prepared as detailed below (see
scheme 9) from
4-(1-{2S-[3-(Benzyloxy-formyl-amino)-2R-cyclopentylmethyl-propionyla-
mino]-3,3-dimethyl-butyryl}-piperidin-4-yloxy)-benzoic acid methyl
ester (scheme 8).
##STR00128##
[0332] To a solution of
4-(1-{2S-[3-(Benzyloxy-formyl-amino)-2R-cyclopentylmethyl-propionylamino]-
-3,3-dimethyl-butyryl}-piperidin-4-yloxy)-benzoic acid methyl ester
(80 mg, 0.125 mmol) in EtOH (4 ml) was added Pd/C (10 mg). To the
resulting suspension, H.sub.2 was bubbled for 2 h. Pd/C was
filtered off through a celite pad to give the desired compound in
88% yield.
[0333] .sup.1H NMR .delta. (CDCl.sub.3), 8.40 (0.3H, s), 7.99 (2H,
dd, J.sub.1=3.04 J.sub.2=8.85), 7.81 (0.7H, s), 6.91 (2H, dd,
J.sub.1=4.87 J.sub.2=8.84), 6.78 (1H, m), 4.94 (1H, m), 4.64 (1H,
m), 3.99 (2H, m), 3.89 (3H, s), 3.75 (2H, m), 3.48 (3H, m), 2.81
(1H, m), 2.10-1.32 (13H, m), 1.08 (2H, bs), 0.97 (9H, m); .sup.13C
NMR .delta. (CDCl.sub.3), 175.7, 173.6, 170.3, 167.1, 161.2, 132.1,
123.4, 115.5, 72.3, 58.7, 55.1, 54.8, 52.9, 52.3, 44.2, 43.6, 39.2,
39.1, 38.4, 36.6, 35.8, 33.2, 31.6, 31.2, 27.0, 25.5,
Example 95
2R-Cyclopentylmethyl-3-(formyl-hydroxy-amino)-N-{1S-[4-(4-hydroxymethyl-ph-
enoxy)-piperidine-1-carbonyl]-2,2-dimethyl-propyl}-propionamide
##STR00129##
[0335] The title compound was prepared as detailed below (see
scheme 10) from
4-[1-(2S-Benzyloxycarbonylamino-3,3-dimethyl-butyryl)-piperidin-4-yl-
oxy]-benzoic acid
##STR00130##
Step A:
{1S-[4-(4-Hydroxymethyl-phenoxy)-piperidine-1-carbonyl]-2,2-dimet-
hyl-propyl}-carbamic acid benzyl ester
[0336] To a cold (10.degree. C.) solution of the
4-[1-(2S-Benzyloxycarbonylamino-3,3-dimethyl-butyryl)-piperidin-4-yloxy]--
benzoic acid (750 mg, 1.6 mmol) in THF (10 ml) was added dropwise
BH.sub.3 The reaction mixture was stirred at room temperature for
12 hours. Water was then added dropwise and the solvent removed
under reduced pressure. The crude material was taken-up in EtOAc.
After filtration, the organic layer was concentrated to yield a
white foam as a pure compound in 93% yield.
[0337] .sup.1H NMR .delta. (CDCl.sub.3), 7.35-7.28 (7H, m), 6.89
(2H, m), 5.60 (1H, m), 5.15-5.03 (2H, AB system), 4.65-4.48 (3H,
m), 3.91-3.51 (5H, m), 1.95-1.25 (4H, m), 1.00 (9H, s). ESMS: +ve
ion 477 [M+Na], HPLC: RT=6.3 min, 93% pure.
Step B:
2S-Amino-1-[4-(4-hydroxymethyl-phenoxy)-piperidin-1-yl]-3,3-dimeth-
yl-butan-1-one
[0338] To a solution of the latter compound (680 mg, 1.49 mmol) in
EtOH (10 ml) was added Pd/C (68 mg) and H.sub.2 was bubbled through
the resulting suspension for 2 hours. The reaction mixture was then
stirred for two hours under a blanket of H.sub.2. Pd/C was then
filtered off through a celite pad. The solvent was removed under
reduced pressure to give the desired compound in 94% yield. .sup.1H
NMR .delta. (CDCl.sub.3), 7.29-6.86 (4H, AB system), 4.62 (2H, s),
4.55 (1H, m), 3.82-3.58 (2H, m), 1.92-1.73 (11H), 1.00 (9H, s).
ESMS: +ve ion 321 [M+1].
Step C:
3-(Benzyloxy-formyl-amino)-2R-cyclopentylmethyl-N-{1S-[4-(4-hydrox-
ymethyl-phenoxy)-piperidine-1-carbonyl]-2,2-dimethyl-propyl}-propionamide
[0339] To a solution of the latter compound, were added PFP ester
(635 mg, 1.35 mmol) and NEt.sub.3 (193 ml, 1.41 mmol). The reaction
mixture was then stirred for 12 hours. DMF was removed under
reduced pressure and the crude material was taken-up in EtOAc,
washed with water, sodium carbonate (1N), saturate aqueous solution
of NH.sub.4Cl and brine. The combined organic layer was dried over
MgSO.sub.4 and the solvent was removed under reduced pressure.
After purification through flash chromatography the desired adduct
was obtained as a white foam in 63% yield. .sup.1H NMR; .delta.
(CDCl.sub.3), 8.13 (0.25H, m), 7.88 (0.25H, m), 7.38 (5H, s), 7.27
(2.5H, m), 6.87 (2H, m), 6.32 (1H, m), 4.89 (3H, m), 4.56 (3H, m),
3.96 (1H, m), 3.73 (2H, m), 3.45 (1H, m), 2.60 (1H, m), 2.06-1.31
(15H, m), 1.06 (11H, m); ESMS: +ve ion 630 [M+Na], HPLC: RT=6.31
min, 100% pure.
Step D:
2R-Cyclopentylmethyl-3-(formyl-hydroxy-amino)-N-{1S-[4-(4-hydroxym-
ethyl-phenoxy)-piperidine-1-carbonyl]-2,2-dimethyl-propyl}-propionamide
[0340] To a solution of the latter compound (50 mg, 0.08 mmol) in
MeOH (3 ml) were added HCO.sub.2NH.sub.4 (26 mg, 0.41 mmol) and
Pd/C (5 mg). The resulting suspension was stirred for 2 hours. Pd/C
was filtered off. The solvent was removed under reduced pressure
and the crude material taken-up in EtOAc, washed with water and
brine. The combined organic layer was dried over MgSO.sub.4 and the
solvent was removed under reduced pressure to yield the expected
compound in 62% yield. .sup.1H NMR; .delta. (CDCl.sub.3), 8.39
(0.3H, s), 7.81 (0.7H, s), 7.29 (2H, dd, J.sub.1=3.47
J.sub.2=9.11), 6.89 (2H, dd, J.sub.1=3.64 J.sub.2=8.55), 6.73 (1H,
m), 4.94 (1H, m), 4.62 (3H, m), 4.01 (2H, m), 3.76 (2H, m), 3.48
(3H, m), 2.74 (1H, m), 2.08-1.35 (19H, m), 1.02 (13H, m); ESMS: +ve
ion 540 [M+Na], -ve ion 516 [M-1] HPLC: RT=5.49 min, 100% pure.
Biological Example
[0341] Minimal inhibitory concentrations (MIC) of compounds of the
invention against E. coli strain DH5.alpha. (Genotype;
F-.phi.80dlacZ.DELTA.M15.DELTA.(lacZYA-argF)U169 deoR recA1 endA1
hsdR17(r.sub.k.sup.-, m.sub.k.sup.+)phoA supE44.lamda. thi-1 gyrA96
relA1) obtained from GibcoBRL Life Technologies, or Staphylococcus
capitis (American Type Culture Collection number 35661) were
determined as follows. Stock solutions of each test compound were
prepared by dissolution of the compound in dimethylsulfoxide at 10
mM. For the determination of the minimal inhibitory concentration,
two fold serial dilutions were prepared in 2xYT broth (typtone 16
g/l, yeast extract 10 g/l, sodium chloride 5 g/l obtained from BIO
101 Inc, 1070 Joshua Way, Vista, Calif. 92083, USA) to yield 0.05
ml compound-containing medium per well. Inocula were prepared from
cultures grown overnight in 2xYT broth at 37.degree. C. Cell
densities were adjusted to absorbance at 660 nm (A.sub.660)=0.1;
the optical density-standardised preparations were diluted 1:1000
in 2xYT broth; and each well inoculated with 0.05 ml of the diluted
bacteria. Microtiter plates were incubated at 37.degree. C. for 18
hours in a humidified incubator. The MIC (.mu.M) was recorded as
the lowest drug concentration that inhibited visible growth.
[0342] In general, the compounds of the Examples were more active
against the Gram positive S. capitis than the Gram negative E.
coli. Results for some of the compounds of the Examples are
reported in Table 8:
TABLE-US-00010 TABLE 8 E. Coli S. Capitis Example No. MIC (.mu.M)
(.mu.M) 24 >200, <400 100 29 100 >200, <400 44 200 12
50 200 6.2 52 200 6.2 54 200 3.1 55 200 6.2 56 50 25 57 100 6.2 69
200 25 74 200 25 78 >200, <400 200 79 >200, <400 6.25
88 100 6.2 89 200 25 91 200 25
[0343] Using the above protocol for establishing the MIC values
against S. capitis, it appears that in general compounds of the
invention of formula (II) wherein Q is a hydroxamate group have
activities comparable to compounds of similar structure wherein Q
is an N-formylhydroxylamine group.
[0344] In another experiment, the MICs of the compound of Example
91 were determined against certain respiratory tract pathogens,
using the Microdilution Broth Method according to the approved
standard of the National Committee for Clinical Laboratory
Standards procedure (Methods for dilution antimicrobial
susceptibility tests for bacteria that grow aerobically--Fourth
Edition ISBN 1-56238-309-4). The results appear in Table 9.
TABLE-US-00011 TABLE 9 Organism MIC (.mu.g/ml) Moraxella
catarrhalis 2413 0.25 Moraxella catarrhalis 2412 0.5 Haemophilus
Infuenzae 1414 4 Haemophilus Infuenzae 1390 1 Streptococcus
pneumoniae (PRP) 2390 0.25 Streptococcus pneumoniae (PIP) 2391 0.25
Streptococcus pneumoniae (PSP) 2403 0.25
* * * * *