U.S. patent number RE40,259 [Application Number 11/359,982] was granted by the patent office on 2008-04-22 for alpha-aminoamide derivatives useful as analgesic agents.
This patent grant is currently assigned to Newron Pharmaceuticals, S.p.A.. Invention is credited to Paolo Pevarello, Claes Post, Patricia Salvati, Mario Varasi.
United States Patent |
RE40,259 |
Pevarello , et al. |
April 22, 2008 |
Alpha-aminoamide derivatives useful as analgesic agents
Abstract
The present invention relates to novel and known
alpha-aminoamide compounds, to a process for their preparation, to
pharmaceutical composition containing them and to their use as
therapeutic agents. In particular, the compounds of the present
invention are endowed with analgesic properties and are
particularly useful for the treatment and alleviation of chronic
and neuropathic pain. Accordingly, one object of the present
invention is to provide the use of a compound of formula (I)
##STR00001## wherein: A is a --(CH.sub.2).sub.m--,
--(CH.sub.2).sub.n--X-- or --(CH.sub.2).sub.v--O-- group wherein m
is an integer of 1 to 4, n is zero or an integer of 1 to 4, X is
--S-- or --NH--, and v is zero or an integer of 1 to 5; s is 1 or
2; R is a furyl, thienyl, or pyridyl ring or a phenyl ring
optionally substituted by one or two substituents independently
chosen from halogen, cyano, C.sub.1-C.sub.4 alkyl, C.sub.1-C.sub.4
alkoxy and trifluoromethyl; R.sub.1 is hydrogen or C.sub.1-C.sub.4
alkyl; one of R.sub.2 and R.sub.3 is hydrogen and the other is
hydrogen or C.sub.1-C.sub.4 alkyl optionally substituted by hydroxy
or phenyl; or R.sub.2 and R.sub.3 taken together with the carbon
atom to which they are linked form a C.sub.3-C.sub.6 cycloalkyl
ring; or R.sub.2 and R.sub.3 are both methyl; R.sub.4 is hydrogen
or C.sub.1-C.sub.4 alkyl.
Inventors: |
Pevarello; Paolo (Madrid,
ES), Varasi; Mario (Milan, IT), Salvati;
Patricia (Arese, IT), Post; Claes (Sigtuna,
SE) |
Assignee: |
Newron Pharmaceuticals, S.p.A.
(Milan, IT)
|
Family
ID: |
10824342 |
Appl.
No.: |
11/359,982 |
Filed: |
December 12, 1998 |
PCT
Filed: |
December 12, 1998 |
PCT No.: |
PCT/EP98/08157 |
371(c)(1),(2),(4) Date: |
August 29, 2000 |
PCT
Pub. No.: |
WO99/35125 |
PCT
Pub. Date: |
July 15, 1999 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
09582198 |
Aug 29, 2000 |
06306903 |
Oct 23, 2001 |
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Foreign Application Priority Data
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|
|
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Dec 31, 1997 [GB] |
|
|
9727523 |
|
Current U.S.
Class: |
514/522; 564/171;
564/164; 514/620; 564/163; 558/414; 514/619 |
Current CPC
Class: |
C07C
237/06 (20130101); A61P 29/00 (20180101); C07C
255/54 (20130101); A61P 25/04 (20180101); A61K
31/165 (20130101) |
Current International
Class: |
A61K
31/275 (20060101); A61K 31/165 (20060101); C07C
233/05 (20060101); C07C 255/50 (20060101) |
Field of
Search: |
;514/522,619,620
;558/414 ;564/163,164,171 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0200101 |
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EP |
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EP |
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0 525 360 |
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Feb 1993 |
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EP |
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Jan 1969 |
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GB |
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2059963 |
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Apr 1981 |
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GB |
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WO 90/14334 |
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Nov 1990 |
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WO |
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WO 94/22808 |
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Oct 1994 |
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WO |
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WO 94/22809 |
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Oct 1994 |
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WO |
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WO 96/40628 |
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WO |
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Jun 1999 |
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WO |
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WO 99/39712 |
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Aug 1999 |
|
WO |
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Primary Examiner: Anderson; Rebecca
Attorney, Agent or Firm: Dechert, LLP
Claims
What is claimed is:
1. A method of treating .Iadd.acute or chronic .Iaddend.pain in a
patient in need thereof, said method comprising administering to
.[.the.]. .Iadd.a .Iaddend.patient .Iadd.in need of such treatment
.Iaddend.a medicament comprising an .Iadd.analgesically
.Iaddend.effective amount of .[.an analgesic which is.]. an
alpha-aminoamide compound of formula (I) ##STR00007## wherein: A is
a --(CH.sub.2).sub.m--, --(CH.sub.2).sub.n--X-- or
--(CH.sub.2).sub.v--O-- group wherein m is an integer of 1 to 4, n
is zero or an integer of 1 to 4, X is --S-- or --NH--, and v is
zero or an integer of 1 to 5; s is 1 or 2; R is .[.a ring or.]. a
phenyl ring optionally substituted by one or two substituents
independently .[.chosen.]. .Iadd.selected .Iaddend.from halogen,
cyano, C.sub.1-C.sub.4 alkyl, C.sub.1-C.sub.4 alkoxy and
trifluoromethyl; R.sub.1 is hydrogen or C.sub.1-C.sub.4 alkyl; one
of R.sub.2 and R.sub.3 is hydrogen and the other is hydrogen or
C.sub.1-C.sub.4 alkyl optionally substituted by hydroxy or phenyl;
or R.sub.2 and R.sub.3 taken together with the carbon atom to which
they are linked form a C.sub.3-C.sub.6 cycloalkyl ring; or R.sub.2
and R.sub.3 are both methyl; R.sub.4 is hydrogen or C.sub.1-C.sub.4
alkyl; or a pharmaceutically acceptable salt thereof; with the
proviso that.[.,.]. when A is a --(CH.sub.2).sub.5--O-- group then
s is 1, R is a phenyl group optionally substituted by one or two
substituents selected independently from halogen, trifluoromethyl
and C.sub.1-C.sub.4 alkoxy, R.sub.1 is hydrogen and one of R.sub.2
and R.sub.3 is hydrogen and the other is hydrogen or
C.sub.1-C.sub.4 alkyl optionally substituted .Iadd.by
.Iaddend.hydroxy.
.[.2. A method of treating chronic or neuropathic pain in a patient
in need thereof, said method comprising the method according to
claim 1..].
3. The method according to claim 1 .Iadd.or claim 6.Iaddend.,
wherein in the compound of formula (I), A is a group .[.chosen.].
.Iadd.selected .Iaddend.from --CH.sub.2--, --CH.sub.2CH.sub.2--,
--CH.sub.2--S--, --CH.sub.2--CH.sub.2--S-- and
--(CH.sub.2).sub.v--O-- in which v is an integer of 1 to 5; s is 1
or 2; R is a phenyl ring optionally substituted by one or two
substituents independently .[.chosen.]. .Iadd.selected
.Iaddend.from halogen and cyano .[.or a thienyl ring.]. ; R.sub.1
is hydrogen or C.sub.1-C.sub.4 alkyl; one of R.sub.2 and R.sub.3 is
hydrogen and the other is C.sub.1-C.sub.4 alkyl optionally
substituted by hydroxy or phenyl; or R.sub.2 and R.sub.3 are both
methyl; and R.sub.4 is hydrogen or C.sub.1-C.sub.4 alkyl.
4. .[.A method of treating pain in a patient in need thereof, said
method comprising administering to the patient a medicament
comprising an effective amount of an analgesic which is selected
from the group consisting of:
2-[4-(3-fluorobenzyloxy)benzylamino]-2-methyl-propanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]propanamide;
2-(4-benzyloxybenzylamino)propanamide;
2-[4-(2-fluorobenzyloxy)benzylamino]propanamide;
2-[4-(4-fluorobenzyloxy)benzylamino]propanamide;
2-[4-(2-chlorobenzyloxy)benzylamino]propanamide;
2-[4-(3-chlorobenzyloxy)benzylamino]propanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(2-fluorobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(2-chlorobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(3-cyanobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(3-chlorobenzyloxy)phenylethylamino]-propanamide;
2-(4-benzyloxybenzylamino)-3-hydroxy-N-methyl-propanamide;
2-[4-(2-thenyloxy)benzylamino]-propanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]-N-methylpropanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]-3-hydroxy-propanamide;
2-[4-(2-(3-fluorophenyl)ethyloxy)benzylamino]-propanamide;
2-[4-(2-(3-fluorophenyl)ethyl)benzylamino]-propanamide;
2-[N-4-benzyloxybenzyl-N-methyl-amino]-propanamide;
2-[2-(4-(3-chlorobenzyloxy)phenylethyl)amino]-propanamide;
2-[4-benzylthiobenzylamino]-propanamide;
2-[4-(3-phenylpropyloxy)benzylamino]-propanamide;
2-[4-(4-phenylbutyloxy)benzylamino]-propanamide;
2-[4-(5-phylpentyloxy)benzylamino]-propanamide;
2-[4-benzyloxybenzylamino]-3-phenyl-N-methylpropanamide;
2-[4-benzyloxybenzylamino]-3-methyl-N-methylbutanamide, isomers,
mixtures and pharmaceutically acceptable salts.]. .Iadd.The method
of claim 1 or claim 6 in which the alpha-aminoamide compound is
selected from the group consisting of:
2-[4-(2-fluorobenzyloxy)benzylamino]propanamide and individual
optical isomers and pharmaceutically acceptable salts
.Iaddend.thereof.
5. A pharmaceutical composition .[.having analgesic activity,.].
comprising a pharmaceutically acceptable excipient and.[., as an
active agent,.]. a compound as defined in .[.claim 1.]. .Iadd.claim
9.Iaddend..
6. A method of treating .Iadd.acute or chronic .Iaddend.pain in a
patient in need thereof, said method comprising administering to
.[.the.]. .Iadd.a .Iaddend.patient .Iadd.in need of such treatment
.Iaddend.an .Iadd.analgesically .Iaddend.effective amount of an
alpha-aminoamide compound of formula (I), ##STR00008## or a
pharmaceutically acceptable salt thereof.Iadd., wherein: A is a
--(CH.sub.2).sub.m--, --(CH.sub.2).sub.n--X-- or
--(CH.sub.2).sub.v--O-- group wherein m is an integer of 1 to 4, n
is zero or an integer of 1 to 4, X is --S-- or --NH--, and v is
zero or an integer of 1 to 5; s is 1 or 2; R is a phenyl ring
optionally substituted by one or two substituents independently
selected from halogen, cyano, C.sub.1-C.sub.4 alkyl,
C.sub.1-C.sub.4 alkoxy and trifluoromethyl; R.sub.1 is hydrogen or
C.sub.1-C.sub.4 alkyl; one of R.sub.2 and R.sub.3 is hydrogen and
the other is hydrogen or C.sub.1-C.sub.4 alkyl optionally
substituted by hydroxy or phenyl; or R.sub.2 and R.sub.3 taken
together with the carbon atom to which they are linked form a
C.sub.3-C.sub.6 cycloalkyl ring; or R.sub.2 and R.sub.3 are both
methyl; R.sub.4 is hydrogen or C.sub.1-C.sub.4 alkyl, with the
proviso that when A is a --(CH.sub.2).sub.5--O-- group then s is 1,
R is a phenyl group optionally substituted by one or two
substituents selected independently from halogen, trifluoromethyl
and C.sub.1-C.sub.4 alkoxy, R.sub.1 is hydrogen and one of R.sub.2
and R.sub.3 is hydrogen and the other is hydrogen or
C.sub.1-C.sub.4 alkyl optionally substituted by
hydroxy.Iaddend..
7. A compound which is an alpha-aminoamide of formula (IA)
##STR00009## wherein: A is a --(CH.sub.2).sub.m-- or
--(CH.sub.2).sub.n--E-- group wherein m is an integer of 1 to 4, n
is zero or an integer of 1 to 4 and E is --O--, --S-- or --NH--; s
is 1 or 2; one of R.sub.10 and R.sub.11 is cyano and the other is
independently selected from hydrogen, halogen, cyano,
C.sub.1-C.sub.4 alkyl, C.sub.1-C.sub.4 alkoxy and trifluoromethyl;
R.sub.1 is hydrogen or C.sub.1-C.sub.4 alkyl; one of R.sub.2 and
R.sub.3 is hydrogen and the other is hydrogen or C.sub.1-C.sub.4
alkyl optionally substituted by hydroxy or phenyl; or R.sub.2 and
R.sub.3 taken together with the carbon atom to which they are
linked form a C.sub.3-C.sub.6 cycloalkyl ring; or R.sub.2 and
R.sub.3 are both methyl; R.sub.4 is hydrogen or C.sub.1-C.sub.4
alkyl ring; or a pharmaceutically acceptable salt thereof.
8. A compound according to claim 7, wherein A is a group
--CH.sub.2--O-- or --CH.sub.2--CH.sub.2--O--, s is 1; one of
R.sub.10 and R.sub.11 is cyano and the other is hydrogen, cyano or
halogen; and one of R.sub.2 and R.sub.3 is hydrogen and the other
is C.sub.1-C.sub.4 alkyl optionally substituted by hydroxy; or
R.sub.2 and R.sub.3 are both methyl.
9. A compound selected from the group consisting of:
.[.2-[4-(3-cyanobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
and 2-[4-(3
cyanobenzyloxy)benzyl]-2-methyl-amino]-3-hydroxy-N-methyl-propan-
amide;.].
.Iadd.2-[4-(3-cyanobenzyloxy)benzylamino]-3-hydroxy-N-methylpro-
panamide; and 2-[4-(3 cyanobenzyloxy)benzyl-2-methyl-amino]-
3-hydroxy-N-methyl-propanamide; optical .Iaddend.isomers, mixtures
and pharmaceutically acceptable salts thereof.
10. A pharmaceutical composition comprising a pharmaceutically
acceptable excipient and, as an active agent, a compound as defined
in claim 7.
11. A method of treating .Iadd.acute or chronic .Iaddend.pain in a
patient in need thereof, said method comprising administering to
.[.the.]. .Iadd.a .Iaddend.patient .Iadd.in need of such treatment
.Iaddend.an analgesic which comprises an effective amount of the
compound according to claim 7 and a pharmaceutically acceptable
carrier.
12. A method of treating .Iadd.acute or chronic .Iaddend.pain in a
patient in need thereof, said method comprising administering to
.[.the.]. .Iadd.a .Iaddend.patient .Iadd.in need of such treatment
.Iaddend.an effective amount of the compound according to claim
7.
.Iadd.13. The method of claim 1 or claim 6 in which the
alpha-aminoamide compound is selected from the group consisting of:
2-[4-(3-fluorobenzyloxy)benzylamino]-2-methylpropanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]propanamide;
2-(4-benzyloxybenzylamino)propanamide;
2-[4-(4-fluorobenzyloxy)benzylamino]propanamide;
2-[4-(2-chlorobenzyloxy)benzylamino]propanamide;
2-[4-(3-chlorobenzyloxy)benzylamino]propanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(2-fluorobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(2-chlorobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(3-cyanobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(3-chlorobenzyloxy)phenylethylamino]propanamide;
2-(4-benzyloxybenzylamino)-3-hydroxy-N-methylpropanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]-N-methylpropanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]-3-hydroxypropanamide;
2-[4-(2-(3-fluorophenyl)ethyloxy)benzylamino]propanamide;
2-[4-(2-(3-fluorophenyl)ethyl)benzylamino]propanamide;
2-[N-4-benzyloxybenzyl-N-methyl-amino]propanamide;
2-[2-(4-(3-chlorobenzyloxy)phenylethyl)amino]propanamide;
2-[4-benzylthiobenzylamino]propanamide;
2-[4-(3-phenylpropoxy)benzylamino]propanamide;
2-[4-(4-phenylbutoxy)benzylamino]propanamide;
2-[4-(5-phenylpentoxy)benzylamino]propanamide;
2-[4-benzyloxybenzylamino]-3-phenyl-N-methylpropanamide;
2-[4-benzyloxybenzylamino]-3-methyl-N-methylbutanamide; and optical
isomers, mixtures and pharmaceutically acceptable salts
thereof..Iaddend.
.Iadd.14. The method of claim 1 or claim 6 in which the
alpha-aminoamide compound is selected from the group consisting of:
2-[4-(3-fluorobenzyloxy)benzylamino]propanamide and individual
optical isomers and pharmaceutically acceptable salts
thereof..Iaddend.
.Iadd.15. The method of claim 1 or claim 6, wherein the pain is
neuropathic pain..Iaddend.
.Iadd.16. The method of claim 15, wherein the neuropathic pain is a
peripheral neuropathic pain..Iaddend.
.Iadd.17. The method of claim 15, wherein the pain is trigeminal
neuralgia pain..Iaddend.
.Iadd.18. The method of claim 15, wherein the pain is postherpetic
neuralgia pain..Iaddend.
.Iadd.19. The method of claim 15, wherein the pain is diabetic
neuropathy pain..Iaddend.
.Iadd.20. The method of claim 15, wherein the pain is radiculopathy
pain..Iaddend.
.Iadd.21. The method of claim 15, wherein the pain is
glossopharyngeal neuralgia pain..Iaddend.
.Iadd.22. The method of claim 15, wherein the pain is neuropathic
pain secondary to metastatic infiltration..Iaddend.
.Iadd.23. The method of claim 1 or claim 6, wherein the pain is
burn pain..Iaddend.
.Iadd.24. The method of claim 1 or claim 6, wherein the pain is
chronic pain..Iaddend.
.Iadd.25. The method of claim 1 or claim 6, wherein the pain is
inflammatory pain..Iaddend.
.Iadd.26. The method of claim 1 or claim 6, wherein the pain is
adiposis dolorosa pain..Iaddend.
.Iadd.27. The method of claim 1 or claim 6, wherein the pain is
post-stroke central pain..Iaddend.
.Iadd.28. The method of claim 1 or claim 6, wherein the pain is
thalamic lesion pain..Iaddend.
.Iadd.29. The method of claim 1 or claim 6, wherein the pain is
multiple sclerosis pain..Iaddend.
.Iadd.30. The method of claim 1 or claim 6, wherein the pain is
acute pain..Iaddend.
.Iadd.31. The method of claim 4, wherein the pain is neuropathic
pain..Iaddend.
.Iadd.32. The method of claim 31, wherein the neuropathic pain is a
peripheral neuropathic pain..Iaddend.
.Iadd.33. The method of claim 31, wherein the pain is trigeminal
neuralgia pain..Iaddend.
.Iadd.34. The method of claim 31, wherein the pain is postherpetic
neuralgia pain..Iaddend.
.Iadd.35. The method of claim 31, wherein the pain is diabetic
neuropathy pain..Iaddend.
.Iadd.36. The method of claim 31, wherein the pain is radiculopathy
pain..Iaddend.
.Iadd.37. The method of claim 31, wherein the pain is
glossopharyngeal neuralgia pain..Iaddend.
.Iadd.38. The method of claim 31, wherein the pain is neuropathic
pain secondary to metastatic infiltration..Iaddend.
.Iadd.39. The method of claim 4, wherein the pain is burn
pain..Iaddend.
.Iadd.40. The method of claim 4, wherein the pain is chronic
pain..Iaddend.
.Iadd.41. The method of claim 4, wherein the pain is inflammatory
pain..Iaddend.
.Iadd.42. The method of claim 4, wherein the pain is adiposis
dolorosa pain..Iaddend.
.Iadd.43. The method of claim 4, wherein the pain is post-stroke
central pain..Iaddend.
.Iadd.44. The method of claim 4, wherein the pain is thalamic
lesion pain..Iaddend.
.Iadd.45. The method of claim 4, wherein the pain is multiple
sclerosis pain..Iaddend.
.Iadd.46. The method of claim 4, wherein the pain is acute
pain..Iaddend.
.Iadd.47. The method of claim 14, wherein the pain is neuropathic
pain..Iaddend.
.Iadd.48. The method of claim 47, wherein the neuropathic pain is a
peripheral neuropathic pain..Iaddend.
.Iadd.49. The method of claim 47, wherein the pain is trigeminal
neuralgia pain..Iaddend.
.Iadd.50. The method of claim 47, wherein the pain is postherpetic
neuralgia pain..Iaddend.
.Iadd.51. The method of claim 47, wherein the pain is diabetic
neuropathy pain..Iaddend.
.Iadd.52. The method of claim 47, wherein the pain is radiculopathy
pain..Iaddend.
.Iadd.53. The method of claim 47, wherein the pain is
glossopharyngeal neuralgia pain..Iaddend.
.Iadd.54. The method of claim 47, wherein the pain is neuropathic
pain secondary to metastatic infiltration..Iaddend.
.Iadd.55. The method of claim 14, wherein the pain is burn
pain..Iaddend.
.Iadd.56. The method of claim 14, wherein the pain is chronic
pain..Iaddend.
.Iadd.57. The method of claim 14, wherein the pain is inflammatory
pain..Iaddend.
.Iadd.58. The method of claim 14, wherein the pain is adiposis
dolorosa pain..Iaddend.
.Iadd.59. The method of claim 14, wherein the pain is post-stroke
central pain..Iaddend.
.Iadd.60. The method of claim 14, wherein the pain is thalamic
lesion pain..Iaddend.
.Iadd.61. The method of claim 14, wherein the pain is multiple
sclerosis pain..Iaddend.
.Iadd.62. The method of claim 14, wherein the pain is acute
pain..Iaddend.
.Iadd.63. The method of claim 1 or claim 6, wherein the
administering is by oral administration..Iaddend.
.Iadd.64. The method of claim 63, wherein the administering is by
oral administration of a tablet..Iaddend.
.Iadd.65. The method of claim 63, wherein the administering is by
oral administration of a capsule..Iaddend.
.Iadd.66. The method of claim 63, wherein the administering is by
oral administration of liquid solution or liquid
suspension..Iaddend.
.Iadd.67. The method of claim 1 or claim 6, wherein the
administering is by parenteral administration..Iaddend.
.Iadd.68. The method of claim 67, wherein the parenteral
administration is intravenous administration..Iaddend.
.Iadd.69. The method of claim 68, wherein the intravenous
administration is by intravenous infusion..Iaddend.
.Iadd.70. The method of claim 68, wherein the intravenous
administration is by intravenous injection..Iaddend.
.Iadd.71. The method of claim 67, wherein parenteral administration
is by intramuscular injection..Iaddend.
.Iadd.72. The method of claim 1 or claim 6, wherein the
administering is by rectal administration..Iaddend.
.Iadd.73. The method of claim 4, wherein the administering is by
oral administration..Iaddend.
.Iadd.74. The method of claim 73, wherein the administering is by
oral administration of a tablet..Iaddend.
.Iadd.75. The method of claim 73, wherein the administering is by
oral administration of a capsule..Iaddend.
.Iadd.76. The method of claim 73, wherein the administering is by
oral administration of liquid solution or liquid
suspension..Iaddend.
.Iadd.77. The method of claim 4, wherein the administering is by
parenteral administration..Iaddend.
.Iadd.78. The method of claim 77, wherein parenteral administration
is intravenous administration..Iaddend.
.Iadd.79. The method of claim 78, wherein intravenous
administration is by intravenous infusion..Iaddend.
.Iadd.80. The method of claim 78, wherein intravenous
administration is by intravenous injection..Iaddend.
.Iadd.81. The method of claim 77, wherein parenteral administration
is by intramuscular injection..Iaddend.
.Iadd.82. The method of claim 4, wherein the administering is by
rectal administration..Iaddend.
.Iadd.83. The method of claim 14, wherein the administering is by
oral administration..Iaddend.
.Iadd.84. The method of claim 83, wherein the administering is by
oral administration of a tablet..Iaddend.
.Iadd.85. The method of claim 83, wherein the administering is by
oral administration of a capsule..Iaddend.
.Iadd.86. The method of claim 83, wherein the administering is by
oral administration of liquid solution or liquid
suspension..Iaddend.
.Iadd.87. The method of claim 14, wherein the administering is by
parenteral administration..Iaddend.
.Iadd.88. The method of claim 87, wherein parenteral administration
is intravenous administration..Iaddend.
.Iadd.89. The method of claim 88, wherein intravenous
administration is by intravenous infusion..Iaddend.
.Iadd.90. The method of claim 88, wherein intravenous
administration is by intravenous injection..Iaddend.
.Iadd.91. The method of claim 87, wherein parenteral administration
is by intramuscular injection..Iaddend.
.Iadd.92. The method of claim 14, wherein the administering is by
rectal administration..Iaddend.
.Iadd.93. The method of claim 63, wherein 1-500 mg of the
alpha-aminoamide compound is administered orally per
day..Iaddend.
.Iadd.94. The method of claim 63, wherein 500 mg-1000 mg of the
alpha-aminoamide compound is administered orally per
day..Iaddend.
.Iadd.95. The method of claim 63, wherein 1000-1500 mg of the
alpha-aminoamide compound is administered orally per
day..Iaddend.
.Iadd.96. The method of claim 63, wherein 1500-2000 mg of the
alpha-aminoamide compound is administered orally per
day..Iaddend.
.Iadd.97. The method of claim 73, wherein 1-500 mg of the
alpha-aminoamide compound is administered orally per
day..Iaddend.
.Iadd.98. The method of claim 73, wherein 500 mg-1000 mg of the
alpha-aminoamide compound is administered orally per
day..Iaddend.
.Iadd.99. The method of claim 73, wherein 1000-1500 mg of the
alpha-aminoamide compound is administered orally per
day..Iaddend.
.Iadd.100. The method of claim 73, wherein 1500-2000 mg of the
alpha-aminoamide compound is administered orally per
day..Iaddend.
.Iadd.101. The method of claim 1 or claim 6, wherein the
pharmaceutically acceptable salt is a methanesulfonate
salt..Iaddend.
.Iadd.102. The method of claim 4, wherein the pharmaceutically
acceptable salt is a methanesulfonate salt..Iaddend.
.Iadd.103. The method of claim 14, wherein the pharmaceutically
acceptable salt is a methanesulfonate salt..Iaddend.
.Iadd.104. The method of claim 4, wherein
2-[4-(2-fluorobenzyloxy)benzylamino]propanamide methanesulfonate is
administered orally to a human patient at a dose of 1-2000
mg/day..Iaddend.
.Iadd.105. The method of claim 104, wherein
2-[4-(2-fluorobenzyloxy)benzylamino]propanamide methanesulfonate is
administered orally to a human patient at a dose of 500-1000
mg/day..Iaddend.
.Iadd.106. The method of claim 104, wherein the pain is neuropathic
pain..Iaddend.
.Iadd.107. The method of claim 105, wherein the pain is neuropathic
pain..Iaddend.
.Iadd.108. The method of claim 104, wherein the pain is
inflammatory pain..Iaddend.
.Iadd.109. The method of claim 105, wherein the pain is
inflammatory pain..Iaddend.
.Iadd.110. The method of claim 104, wherein the pain is chronic
pain..Iaddend.
.Iadd.111. The method of claim 105, wherein the pain is chronic
pain..Iaddend.
.Iadd.112. The method of claim 104, wherein the pain is
radiculopathy pain..Iaddend.
.Iadd.113. The method of claim 105, wherein the pain is
radiculopathy pain..Iaddend.
Description
This appln is a 371 of PCT/EP98/08157 filed Dec. 12, 1998.
The present invention relates to novel and known alpha-aminoamide
compounds, to a process for their preparation, to pharmaceutical
composition containing them and to their use as therapeutic
agents.
In particular, the compounds of the present invention are endowed
with analgesic properties and are particularly useful for the
treatment and alleviation of chronic and neuropathic pain.
Chronic and neuropathic pain are associated with prolonged tissue
damage or injuries to the peripheral or central nervous system and
result from a number of complex changes in nociceptive
pathways.
Clinical manifestations of chronic pain include a sensation of
burning or electric shock, feelings of bodily distortion, allodynia
and hyperpathia.
Despite the large number of available analgesics, their use is
limited by severe side effects and modest activity in some pain
conditions. Therefore there is still a clear need to develop new
compounds.
International applications WO 90/14334, WO 94/22808, WO 97/05111
and WO 97/05102 disclose substituted benzylaminopropionamide
compounds active on the central nervous system and useful as
anti-epileptic, anti-Parkinson, neuroprotective, antidepressant,
antispastic and hypnotic agents.
The present invention is based on the finding that compounds known
from the above-cited international applications and new ones,
closely related thereto, have analgesic properties in mammals,
including humans.
Accordingly, one object of the present invention is to provide the
use of a compound of formula (I) ##STR00002## wherein: A is a
--(CH.sub.2).sub.m--, --(CH.sub.2).sub.n--X-- or
--(CH.sub.2).sub.v--O-- group wherein m is an integer of 1 to 4, n
is zero or an integer of 1 to 4, X is --S-- or --NH--, and v is
zero or an integer of 1 to 5; s is 1 or 2; R is a furyl, thienyl,
or pyridyl ring or a phenyl ring optionally substituted by one or
two substituents independently chosen from halogen, cyano,
C.sub.1-C.sub.4 alkyl, C.sub.1-C.sub.4 alkoxy and trifluoromethyl;
R.sub.1 is hydrogen or C.sub.1-C.sub.4 alkyl; one of R.sub.2 and
R.sub.3 is hydrogen and the other is hydrogen or C.sub.1-C.sub.4
alkyl optionally substituted by hydroxy or phenyl; or R.sub.2 and
R.sub.3 taken together with the carbon atom to which they are
linked form a C.sub.3-C.sub.6 cycloalkyl ring; or R.sub.2 and
R.sub.3 are both methyl; R.sub.4 is hydrogen or C.sub.1-C.sub.4
alkyl; or a pharmaceutically acceptable salt thereof; and wherein
when A is a --(CH.sub.2).sub.5--O-- group then s is 1, R is a
phenyl group optionally substituted by one or two substituents
selected independently from halogen, trifluoromethyl and
C.sub.3-C.sub.4 alkoxy, R.sub.1 is hydrogen and one of R.sub.2 and
R.sub.3 is hydrogen and the other is hydrogen or C.sub.1-C.sub.4
alkyl optionally substituted hydroxy; and wherein when R.sub.2 and
R.sub.3 are both methyl then R is other than furyl, thienyl or
pyridyl ring, in the manufacture of a medicament for use as
analgesic, in particular for the treatment and alleviation of
chronic and neuropathic pain.
A --(CH.sub.2).sub.m--, --(CH.sub.2).sub.n-- or
--(CH.sub.2).sub.v-- chain may be a branched or straight chain.
Alkyl and alkoxy groups may be branched or straight groups.
Representative examples of C.sub.1-C.sub.4 alkyl groups include
methyl, ethyl, n- and iso-propyl, n-, iso- sec- and tert-butyl.
Representative examples of C.sub.1-C.sub.4 alkoxy groups include
methoxy and ethoxy.
A C.sub.3-C.sub.6 cycloalkyl group is for instance cyclopropyl,
cyclopentyl or cyclohexyl, in particular cyclopentyl or
cyclohexyl.
A halogen atom is fluorine, bromine, chlorine or iodine, in
particular, chlorine or fluorine.
Pharmaceutically acceptable salts of the compounds of the invention
include acid addition salts with inorganic, e.g. nitric,
hydrochloric, hydrobromic, sulphuric, perchloric and phosphoric
acids or organic, e.g. acetic, trifluoroacetic, propionic,
glycolic, lactic, oxalic, malonic, malic, maleic, tartaric, citric,
benzoic, cinnamic, mandelic and salicylic acids.
The compounds of formula (I) have asymmetric carbon atoms and
therefore they can exist either as racemic mixtures or as
individual optical isomers (enantiomers).
Accordingly, the present invention also include within its scope
all the possible isomers and their mixtures and both the
metabolites and the pharmaceutically acceptable bioprecursors
(otherwise known as pro-drugs) of the compounds of formula (I).
Preferred compounds of formula (I) are those wherein A is a group
chosen from --CH.sub.2--, --CH.sub.2--CH.sub.2--, --CH.sub.2--S--,
--CH.sub.2--CH.sub.2--S-- and --(CH.sub.2).sub.v--O-- in which v is
an integer of 1 to 5; s is 1 or 2; R is a phenyl ring optionally
substituted by one or two substituents independently chosen from
halogen and cyano or a thienyl ring; R.sub.1 is hydrogen or
C.sub.1-C.sub.4 alkyl; one of R.sub.2 and R.sub.3 is hydrogen and
the other is C.sub.1-C.sub.4 alkyl optionally substituted by
hydroxy or phenyl; or R.sub.2 and R.sub.3 are both methyl; R.sub.4
is hydrogen or C.sub.1-C.sub.4 alkyl; and the pharmaceutically
acceptable salts thereof.
Examples of specific compounds of formula (I) are:
2-[4-(3-fluorobenzyloxy)benzylamino]-2-methylpropanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]propanamide;
2-([4-benzyloxybenzylamino)propanamide;
2-[4-(2-fluorobenzyloxy)benzylamino]propanamide;
2-[4-(4-fluorobenzyloxy)benzylamino]propanamide;
2-[4-(2-chlorobenzyloxy)benzylamino]propanamide;
2-(4-(3-chlorobenzyloxy)benzylamino]propanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(2-fluorobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(2-chlorobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(3-cyanobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
2-[4-(3-chlorobenzyloxy)phenylethylamino]-propanamide;
2-(4-benzyloxybenzylamino)-3-hydroxy-N-methylpropanamide;
2-(4-(2-thenyloxy)benzylamino)-propanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]-N-methylpropanamide;
2-[4-(3-fluorobenzyloxy)benzylamino]-3-hydroxypropanamide;
2-[4-(2-(3-fluorophenyl)ethyloxy)benzylamino]-propanamide;
2-[4-(2-(3-fluorophenyl)ethyl)benzylamino]-propanamide;
2-[N-4-benzyloxybenzyl-N-methyl-amino]-propanamide;
2-[2-(4-(3-chlorobenzyloxy)phenylethyl)amino]-propanamide;
2-[4-benzylthiobenzylamino]-propanamide;
2-[4-(3-phenylpropyloxy)benzylamino]-propanamide;
2-[4-(4-phenylbutyloxy)benzylamino]-propanamide;
2-[4-(5-phenylpentyloxy)benzylamino]-propanamide;
2-[4-benzyloxybenzylamino]-3-phenyl-N-methylpropanamide;
2-[4-benzyloxybenzylamino]-3-methyl-N-methylbutanamide, if the case
either as a single isomer or as a mixture thereof, and the
pharmaceutically acceptable salts thereof.
An aspect of this invention relates to a pharmaceutically
composition having analgesic activity, in particular against
chronic and neuropathic pain, comprising a compound of formula (I),
as herein defined, as an active agent and a pharmaceutically
acceptable salt thereof.
A further aspect of this invention relates to a method of treating
a mammal, including humans, in need of an analgesic agent, said
method comprising administering thereto an effective amount of a
compound of formula (I) or a pharmaceutically acceptable salt
thereof.
Neuropathic and chronic pain conditions in a mammal can thus be
alleviated and treated. Examples of pain conditions that can be
treated by a compound of formula (I) include: peripheral
neuropathies, such as trigeminal neuralgia, postherapeutic
neuralgia, diabetic neuropathy, glossopharyngeal neuralgia,
radiculopathy, and neuropathy secondary to metastatic infiltration,
adiposis dolorosa and burn pain; and central pain conditions
following stroke, thalamic lesions and multiple sclerosis.
"Treatment" as used herein covers any treatment of a condition in a
mammal, particularly a human, and includes: (i) preventing the
disease from occurring in a subject which may be predisposed to the
disease, but has not yet been diagnosed as having it; (ii)
inhibiting the condition, i.e., arresting its development; or (iii)
relieving the condition, i.e., causing regression of the
disease.
Another object of the present invention are the novel compounds of
formula (IA) ##STR00003## wherein: A is a --(CH.sub.2).sub.m-- or
--(CH.sub.2).sub.n--E-- group wherein m is an integer of 1 to 4, n
is zero or an integer of 1 to 4 and E is --O--, --S-- or --NH--; s
is 1 or 2; one of R.sub.10 and R.sub.11 is cyano and the other is
independently selected from hydrogen, halogen, cyano,
C.sub.1-C.sub.4 alkyl, C.sub.1-C.sub.4 alkoxy and trifluoromethyl;
R.sub.1 is hydrogen or C.sub.1-C.sub.4 alkyl; one of R.sub.2 and
R.sub.3 is hydrogen and the other is hydrogen or C.sub.1-C.sub.4
alkyl optionally substituted by hydroxy or phenyl; or R.sub.2 and
R.sub.3 taken together with the carbon atom to which they are
linked form a C.sub.3-C.sub.6 cycloalkyl ring; or R.sub.2 and
R.sub.3 are both methyl; R.sub.4 is hydrogen or C.sub.1-C.sub.4
alkyl; and the pharmaceutically acceptable salts.
The compounds of formula (IA) fall within the scope fo the compound
of formula (I), as herein defined. Therefore all the definitions
and biological properties stated above as to a compound of formula
(I) apply also to a compound of formula (IA).
In particular, preferred compounds of formula (IA) are those
wherein A is a group --CH.sub.2--O-- or --CH.sub.2--CH.sub.2--O--,
s is 1; one of R.sub.10 and R.sub.11 is cyano and the other is
hydrogen, cyano or halogen; and one of R.sub.2 and R.sub.3 is
hydrogen and the other is C.sub.1-C.sub.4 alkyl optionally
substituted by hydroxy; or R.sub.2 and R.sub.3 are both methyl and
the pharmaceutically acceptable salts thereof.
Specific examples of compounds of formula (IA) are:
2-[4-(3-cyanobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamide;
[2-[4-(3-cyanobenzyloxy)benzyl]-2-methyl-amino]-3-hydroxy-N-methyl-propan-
amide, if the case either as a single isomer or as a mixture
thereof, and the pharmaceutically acceptable salts thereof.
The compounds of formula (I) and (IA) and the pharmaceutically
acceptable salts thereof can be obtained by well known processes as
described in the above cited international applications. In
particular, a compound of formula (IA) and the salts thereof can be
obtained by a process comprising:
a) reacting a compound of formula (II) ##STR00004## wherein
R.sub.10, R.sub.11, A and s are as defined above, with a compound
of formula (III) ##STR00005## wherein R.sub.2, R.sub.3 and R.sub.4
are as defined above, in the presence of a reducing agent thus
obtaining a compound of formula (IA) in which R.sub.1 is hydrogen;
or b) reacting a compound of formula (IV) ##STR00006## wherein
R.sub.2, R.sub.3, R.sub.4, R.sub.10, R.sub.11, A and s are as
defined above, with a compound of formula (V) or (VI) in this
latter case in the presence of a reducing agent R'.sub.5W (V)
R''.sub.5CHO (VI) wherein W is a halogen atom; R'.sub.5 is
C.sub.1-C.sub.4 alkyl and R''.sub.5 is hydrogen or C.sub.1-C.sub.3
alkyl, thus obtaining a compound of formula (IA) in which R.sub.1
is C.sub.1-C.sub.4 alkyl; and, if desired, converting a compound of
formula (IA) into another compound of formula (IA) and/or, if
desired, converting a compound of formula (IA) into a
pharmaceutically acceptable salt and/or, if desired, converting a
slat into a free compound.
All the processes described hereabove are analogy processes and can
be carried out according to well known methods in organic
chemistry.
A compound of formula (IV) is a compound of formula (IA) in which
R.sub.1 is hydrogen.
The reaction of a compound of formula (II) with a compound of
formula (III) to give a compound of formula (IA) or (IV) is a
reductive amination reaction which can be carried out according to
well known methods. According to a preferred embodiment of the
invention it may be performed under nitrogen atmosphere, in a
suitable organic solvent, such as an alcohol, e.g. a lower alkanol,
in particular methanol, or in acetonitrile, at a temperature
ranging from about 0.degree. C. to about 40.degree. C., in the
presence of a reducing agent, the most appropriate being sodium
cyanoborohydride.
Occasionally molecular sieves can be added to the reaction mixture
for facilitating the reaction.
In a compound of formula (V) the halogen W is preferably iodine.
The alkylation reaction of a compound of formula (IV) with a
compound of formula (V) can be carried out in a suitable organic
solvent, such as an alcohol, e.g. methanol, ethanol or isopropanol,
in particular in ethanol, at a temperature ranging from about
0.degree. C. to about 50.degree. C.
The alkylation reaction of a compound of formula (IV) with an
aldehyde of formula (VI) can be carried out in a suitable organic
solvent, such as an alcohol, e.g. methanol, ethanol or acetonitrile
in the presence of a suitable reducing agent, such as sodium
cyanoborohydride, at a temperature ranging from about 0.degree. C.
to about 30.degree. C.
A compound of formula (IA) can be converted, as stated above, into
another compound of formula (IA) by known methods. Process-variant
b) above may be regarded as an example of optional conversion of a
compound of formula (IA) into another compound of formula (IA).
Also the optional salification of a compound of formula (IA) as
well as the conversion of a salt into the free compound may be
carried out by conventional methods.
The compounds of formula (II) and (III), (V) and (VI) are known
compounds or can be obtained by known methods. When in the
compounds of the present invention and in the intermediate-products
thereof, groups are present, which need to be protected before
submitting them to the hereabove illustrated reactions, they may be
protected before being reacted and then deprotected according to
methods well known in organic chemistry.
The compounds of formula (I), (IA) and the pharmaceutically
acceptable salts thereof are hereinafter defined as "the compounds
of the invention" or "the active agents of the invention".
Pharmacology
As stated above, the compounds of the invention are active as
analgesic agents, as proven for instance by the fact that they have
been found to be active in the formalin test.
Formalin test is a useful tool for obtaining neurogenic
inflammation and continuous pain (Shibata et al, Pain, 38: 347-352,
1989).
Formalin produces a distinct biphasic response. The early phase
seems to be caused predominantly by C-fibre activation due to
peripheral stimulus, while the late phase appears to be dependent
on the combination of an inflammatory reaction in the peripheral
tissue and functional changes in the dorsal horn of the spinal
cord. This functional changes seem to be initiated by the C-fibre
barrage during the early phase (Tjolsen et al. Pain 51, 5-17,
1992). Substance P and bradykinin participate in the early phase,
while histamine, serotonin, prostaglandins and bradykinin are
involved in the late phase.
Formalin Test
Male .[.NMRI.]. .Iadd.CD-1 .Iaddend.mice (22-25 g) were injected
with 20 .[.ml.]. .Iadd..mu.l .Iaddend.of 2.7% solution of formalin
into the right hindpaw and placed immediately into observation
chambers. The cumulative licking time of the injected paw was
recorded in the acute phase (0-5 min) and in the chronic phase
(30-40 min) of the nociceptive response of formalin.
The two representative compounds of the invention (S)-2-[4-(3-
fluorobenzyloxy)benzylamino]-propanamide, methanesulfonate
(internal code PNU 151774E) and
.[.(S)-[2-[4-(3-fluorobenzyloxy)benzylamino]-2-methyl-propanamide.].
.Iadd.2-[4-(3-fluorobenzyloxy)benzylamino]-2-methyl-propanamide
.Iaddend.(internal code PNU 156654E) were administered 60 min
before formalin injection at the doses of 7.5, 15.0, 30.0 and 60.0
mg/kg; po. Morphine (5 mg/kg; sc) was used as a positive standard.
The activities data .Iadd.were .Iaddend.analysed by Dunnett's
t-test.
Locomotor Activity and Rotarod
The effects of these compounds on locomotor activity and rotarod (a
test for evaluating motor co-ordination) were studied in order to
exclude changes in these parameters as confounding factors in the
evaluation of the formalin response. The locomotor activity test
lasted 15 min. Five minutes after testing locomotor activity, the
mice were put on the rotarod for 2 min and the number of mice
falling within this time were counted.
Compounds PNU 151774E and PNU 156654E were tested at the doses of
7.5, 15.0, 30.0 and 60.0 mg/kg; po. The compounds were administered
60 min before locomotor activity test.
Results
Compounds PNU 151774E and PNU 156654E dose-dependently reduced
cumulative licking time in both phases of the formalin test (Table
1) demonstrating analgesic activity without any effect on locomotor
or rotarod activity (Table 2).
TABLE-US-00001 TABLE 1 Effects of PNU 151774E and PNU 156654E in
the formalin nociception test in mice Licking time Dose (sec)
Compound (mg/kg; po) Acute phase Chronic phase vehicle 0.0 160.2
.+-. 2.6.sup. 74.8 .+-. 3.7.sup. PNU 151774E 7.5 137.9 .+-.
2.4.sup.a 72.4 .+-. 2.4.sup. 15.0 87.9 .+-. 3.3.sup.a 64.3 .+-.
2.8.sup.b 30.0 79.4 .+-. 3.0.sup.a 56.9 .+-. 2.6.sup.a 60.0 63.1
.+-. 2.6.sup.a 38.1 .+-. 3.6.sup.a vehicle 0.0 119.4 .+-. 5.2.sup.
73.1 .+-. 6.0.sup. PNU 156654E 7.5 108.4 .+-. 4.2.sup. 62.4 .+-.
3.6.sup. 15.0 79.7 .+-. 3.7.sup.a 42.1 .+-. 6.2.sup.a 30.0 60.0
.+-. 2.3.sup.a 37.7 .+-. 6.9.sup.a 60.0 44.4 .+-. 4.2.sup.a 17.3
.+-. 6.6.sup.a .sup.a= p < 0.01; .sup.b= p < 0.05
TABLE-US-00002 TABLE 2 Effects of PNU 151774E and PNU 156654E on
locomotor activity and rotarod Rotarod Locomotor co-ordination Dose
activity counts (mice fallen/ Compound (mg/kg; po) (mean .+-. sem)
total mice) vehicle 0 2653 .+-. 163 0/10 PNU 151774E 7.5 2908 .+-.
234 0/10 15 2795 .+-. 255 0/10 30 2347 .+-. 203 0/10 60 2240 .+-.
195 0/10 vehicle 0 1976 .+-. 232 0/10 PNU 156654E 7.5 1966 .+-. 188
0/10 15 2110 .+-. 256 0/10 30 2272 .+-. 317 0/10 60 2119 .+-. 310
0/10
In view of their biological activity, the compounds of the
invention are useful in mammals, including humans, as analgesic
agents. In particular they are useful in treating pain associated
with damage or permanent alteration of the peripheral or central
nervous system, for example peripheral neuropathies, such as
trigeminal neuralgia, postherapeutic neuralgia, diabetic
neuropathy, raticulopathy glossopharyngeal neuralgia, and
neuropathy secondary to metastatic infiltration, adiposis dolorosa,
and burn pain; and central pain conditions following stroke,
thalamic lesions and multiple sclerosis.
The conditions of a patient in need of an analgesic agent may thus
be improved.
The compounds of the invention can be administered in a variety of
dosage forms, e.g. orally, in the form of tablets, capsules, sugar
or film coated tablets, liquid solutions or suspensions; rectally
in the form of suppositories; parenterally, e.g. intramuscularly,
or by intravenous injection or infusion.
The dosage depends on the age, weight, conditions of the patient
and on the administration route; for example, the dosage adopted
for oral administration to adult humans e.g. for the representative
compounds of the invention
(S)-2-[4-(3-fluorobenzyloxy)benzylamino]-propanamide,
methanesulfonate,
.[.(S)-[2-[4-(3-fluorobenzyloxy)benzylamino]-2-methyl-propanamide.].
.Iadd.2-[4-(3-fluorobenzyloxy)benzylamino]-2-methyl-propanamide.Iaddend.,
and
(S)-[2-[4-(3-cyanobenzyloxy)benzylamino]-3-hydroxy-N-methylpropanamid-
e may range from about 1 to about 500 mg pro dose, from 1 to 5
times daily.
The invention includes pharmaceutical compositions comprising a
compound of formula (IA), as an active principle, in association
with a pharmaceutically acceptable excipient (which can be a
carrier or a diluent). The pharmaceutical compositions containing
the compounds of the invention are usually prepared following
conventional methods and are administered in a pharmaceutically
suitable form.
For example, the solid oral forms may contain, together with the
active compound, diluents, e.g. lactose, destrose, saccharose,
cellulose, corn starch or potato starch; lubricants, e.g. silica,
talc, stearic acid, magnesium or calcium stearate, and/or
polyethylene glycols; binding agents, e.g. starches, arabic gums,
gelatin, methylcellulose, carboxymethylcellulose or polyvinyl
pyrrolidone; desegregating agents, e.g. a starch, alginic acid,
alginates or sodium starch glycolate; effervescing mixtures;
dyestuffs; sweeteners; wetting agents such as lecithin,
polysorbates, laurylsulphates; and, in general, non-toxic and
pharmacologically inactive substances used in pharmaceutical
formulations. Said pharmaceutical preparations may be manufactured
in known manner, for example, by means of mixing, granulating,
tabletting, sugar-coating, or film-coating processes.
The liquid dispersion for oral administration may be e.g. syrups,
emulsions and suspension.
The syrups may contain as carrier, for example, saccharose or
saccharose with glycerine and/or mannitol and/or sorbitol.
The suspension and the emulsion may contain as carrier, for
example, a natural gum, agar, sodium alginate, pectin,
methylcellulose, carboxymethylcellulose, or polyvinyl alcohol.
The suspension or solutions for intramuscular injections may
contain, together with the active compound, a pharmaceutically
acceptable carrier, e.g. sterile water, olive oil, ethyl oleate,
glycols, e.g. propylene glycol, and, if desired, a suitable amount
of lidocaine hydrochloride. The solutions for intravenous
injections or infusion may contain as carrier, for example, sterile
water or preferably they may be in the form of sterile, aqueous,
isotonic saline solutions.
The suppositories may contain together with the active compound a
pharmaceutically acceptable carrier, e.g. cocoa butter,
polyethylene glycol, a polyoxyethylene sorbitan fatty acid ester
surfactant or lecithin.
The following examples illustrate but do not limit the
invention.
EXAMPLE 1
(S)-2-[4-(3-cyanobenzyloxy)benzylamino]-3-hydroxy-N-methyl-propanamide
To a solution of N-methylserinamide hydrochloride (2 g; 0.0129
mol), in methanol (40 ml), 2 g of powdered 3A molecular sieves are
added; after stirring 15' at room temperature, 0.65 g (0.0102 mol)
of sodium cyanoborohydride are added in a single portion followed
by 2.85 g (0.012 mol) of 4-(3-cyanobenzyloxy)benzaldehyde. The
mixture is stirred for 2 hours at room temperature, then filtered
and the residue after evaporation is separated by
flash-chromatography on silica gel (eluant: chloroform 98: methanol
2: 30% NH4OH 0.2). 2.6 g (63%) of pure titled compound (m.p.
130-134.degree. C.).
[.alpha.].sub.D: +12.8 (c=1.25 AcOH)
EXAMPLE 2
(S)-[2-[4-(3-cyanobenzyloxy)benzyl]-2-methyl-amino]-3-hydroxy-N-methyl-pro-
panamide
(S)-2-[4-(3-cyanobenzyloxy)benzylamino]-3-hydroxy-N-methyl-propanamide
(2 g; 0.0059 mol) is dissolved in methanol (30 ml) and 1.8 g (0.013
mol) of anhydrous potassium carbonate are added to the solution.
Methyl iodide (1.5 ml; 0.025 mol) is dropped into the mixture which
is stirred for 2 hours at room temperature and then evaporated to
dryness. The crude residue is chromatographed on silica gel
(eluant:chloroform/methanol; 95/5). 1.88 g (90%) of
(S)-[2-[4-(3-cyanobenzyloxy)benzyl]-2-methyl-amino]-3-hydroxy-N-methyl-pr-
opanamide are obtained. Elemental Analysis:
TABLE-US-00003 Atom Calc. Found C 67.97 67.69 H 6.56 6.48 N 11.89
11.98
EXAMPLE 3
With the usual methods of pharmaceutical technique, preparation can
be made of capsules having the following composition:
TABLE-US-00004 (S)-2-[4-(3-cyanobenzyloxy)benzylamino]- 50 mg
3-hydroxy-N-methyl-propanamide Talc 2 mg Corn starch 2 mg
Microcristalline cellulose 6 mg Magnesium stearate 1 mg
* * * * *
References