U.S. patent number RE42,562 [Application Number 11/796,044] was granted by the patent office on 2011-07-19 for ep.sub.4 receptor agonist, compositions and methods thereof.
This patent grant is currently assigned to Merck Frosst Canada. Invention is credited to Xavier Billot, John Colucci, Yongxin Han, Marie-Claire Wilson, Robert N. Young.
United States Patent |
RE42,562 |
Billot , et al. |
July 19, 2011 |
EP.sub.4 receptor agonist, compositions and methods thereof
Abstract
This invention relates to potent selective agonists of the
EP.sub.4 subtype of prostaglandin E2 receptors, their use or a
formulation thereof in the treatment of glaucoma and other
conditions, which are related to elevated intraocular pressure in
the eye of a patient. This invention further relates to the use of
the compounds of this invention for mediating the bone modeling and
remodeling processes of the osteoblasts and osteoclasts.
Inventors: |
Billot; Xavier (Montreal,
CA), Colucci; John (Kirkland, CA), Young;
Robert N. (Vancouver, CA), Han; Yongxin
(Kirkland, CA), Wilson; Marie-Claire (Carlsband
Springs, CA) |
Assignee: |
Merck Frosst Canada (Kirkland,
Quebec, CA)
|
Family
ID: |
33098243 |
Appl.
No.: |
11/796,044 |
Filed: |
April 26, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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60457700 |
Mar 26, 2003 |
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Reissue of: |
10797257 |
Mar 10, 2004 |
7053085 |
May 30, 2006 |
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Current U.S.
Class: |
514/228.8;
544/44; 544/59; 544/96; 546/243; 514/317; 514/227.8; 514/315;
514/227.5; 544/97; 514/227.2 |
Current CPC
Class: |
A61P
29/00 (20180101); C07D 409/06 (20130101); A61P
19/08 (20180101); A61P 1/02 (20180101); A61P
43/00 (20180101); C07D 401/06 (20130101); A61P
27/02 (20180101); A61P 35/04 (20180101); A61P
1/16 (20180101); A61P 3/14 (20180101); C07D
211/74 (20130101); A61P 7/10 (20180101); A61P
19/10 (20180101); C07D 211/76 (20130101); A61P
35/00 (20180101); C07D 265/10 (20130101); A61P
19/02 (20180101); A61P 27/06 (20180101); A61P
9/12 (20180101) |
Current International
Class: |
C07D
265/06 (20060101); A61K 31/5355 (20060101); A61P
27/06 (20060101); C07D 265/32 (20060101); A61K
31/535 (20060101) |
Field of
Search: |
;544/44,59,96,97
;546/243 ;514/227.2,227.5,227.8,315,317 |
References Cited
[Referenced By]
U.S. Patent Documents
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EP |
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EP |
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EP |
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GB |
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WO |
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Apr 2000 |
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WO |
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WO 01/46140 |
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Jun 2001 |
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WO |
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WO 01/70702 |
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Sep 2001 |
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WO |
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WO 02/24647 |
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Mar 2002 |
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WO |
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WO 02/42268 |
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May 2002 |
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WO |
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WO 02/060863 |
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Aug 2002 |
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WO |
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WO 01/72268 |
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Oct 2002 |
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WO |
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WO 02/077168 |
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Oct 2002 |
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WO |
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WO 03/047417 |
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Jun 2003 |
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WO |
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WO 03/047513 |
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Jun 2003 |
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WO |
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WO |
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WO |
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WO 03/105868 |
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Dec 2003 |
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WO |
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WO 2004/063158 |
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Jul 2004 |
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WO |
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Primary Examiner: Habte; Kahsay T
Attorney, Agent or Firm: Ayler; Sulvia A. Devlin; Gerard
M.
Parent Case Text
This application claims the benefit of U.S. Provisional Application
Ser. No. 60/457,700, filed Mar. 26, 2003.
Claims
What is claimed is:
1. A compound having the structural formula I: ##STR00038## or a
pharmaceutically acceptable salt, enantiomer, diastereomer,
.[.prodrug.]. or mixture thereof, wherein, Q is (CH.sub.2).sub.m,
(CH.sub.2).sub.mC.sub.6-10aryl, (CH.sub.2).sub.mC.sub.5-10
heterocyclyl, (CH.sub.2).sub.mC.sub.3-10 heterocycloalkyl,
(CH.sub.2).sub.mC.sub.3-8 cycloalkyl, C(halo).sub.2, said
cycloalkyl, heterocycloalkyl, aryl or heterocyclyl unsubstituted or
substituted with 1-3 groups of R.sup.a; X represents O, Y
represents CH.sub.2; U represents H, C1-3 alkyl or is not present
when W is .dbd.O; W represents OH or .dbd.O, provided that U is not
present when W is .dbd.O; R.sup.1 represents
(CH.sub.2).sub.phydroxy, (CH.sub.2).sub.pCN,
(CH.sub.2).sub.pCO.sub.2R.sup.10, (CH.sub.2).sub.nSO.sub.3R.sup.6,
--(CH.sub.2).sub.pCF.sub.2SO.sub.2NH.sub.2,
--(CH.sub.2).sub.pSO.sub.2NH.sub.2,
.[.--(CH.sub.2).sub.pCONHSO.sub.2R.sub.2.].
.Iadd.--(CH.sub.2).sub.pCONHSO.sub.2R.sup.2.Iaddend.,
--(CH.sub.2).sub.pSO.sub.2NHCOR.sup.2,
--(CH.sub.2).sub.pPO(OH).sub.2,
(CH.sub.2).sub.pCONHPO.sub.2R.sup.6, (CH.sub.2).sub.pCONHR.sup.8,
(CH.sub.2).sub.pC.sub.1-4alkoxy, --(CH.sub.2).sub.pcycloalkyl, or
(CH.sub.2).sub.nheterocyclyl, said heterocyclyl unsubstituted or
substituted with 1 to 3 groups of R.sup.a and optionally containing
an acidic hydroxyl group; R.sup.2 independently represents
C.sub.1-10 alkyl, (CH.sub.2).sub.mC.sub.6-10aryl,
(CH.sub.2).sub.mC.sub.5-10heterocyclyl, (CH.sub.2).sub.mC.sub.3-10
heterocycloalkyl, (CH.sub.2).sub.mC.sub.3-8 cycloalkyl,
O--C.sub.1-10alkyl, O--C.sub.6-10aryl, O--C.sub.3-10cycloalkyl,
O--C.sub.3-10heterocycloalkyl, .[.O--C.sub.3-10
heterocycloalkyl,.]. said alkyl, cycloalkyl, heterocycloalkyl, aryl
or hetrocyclyl unsubstituted or substituted with 1-3 groups of
R.sup.a; R.sup.3 and R.sup.4 independently represents hydrogen,
halogen, or C.sub.1-6 alkyl, or R.sup.3 and R.sup.4 may be taken
together to form a 3-7 membered carbon ring optionally interrupted
with 1-2 heteroatoms chosen from O, S, SO, SO.sub.2, and NR.sup.9;
R.sup.6 and R.sup.7 independently represents hydrogen, or C.sub.1-4
alkyl; R.sup.8 represents hydrogen, acyl, or sulfonyl; R.sup.9
represents hydrogen, C.sub.1-6 alkyl, said alkyl optionally
substituted with 1-3 halogen, CN, OH, C.sub.1-6 alkoxy, C.sub.1-6
acyloxy or amino; R.sup.10 represents hydrogen, C.sub.1-10 alkyl,
C.sub.3-10 cycicoalkyl, (CH.sub.2).sub.pC.sub.6-10 aryl,
(CH.sub.2).sub.pC.sub.5-10 heterocyclyl, CR.sup.6R.sup.7OC(O)O
C.sub.3-10 cycloalkyl or CR.sup.6R.sup.7OC(O)O C.sub.1-10 alkyl; Z
represents a C.ident.C, O, S, (C(R.sup.b).sub.2).sub.n, or
CH.dbd.CH; R.sup.b represents hydrogen, C.sub.1-6 alkyl or halogen;
R.sup.a represents C.sub.1-6 alkoxy, C.sub.1-6 alkyl, CF.sub.3,
nitro, amino, cyano, C.sub.1-6 alkylamino, halogen,
SC.sub.1-6alkyl, SC.sub.6-10aryl, SC.sub.5-10heterocyclyl,
CO.sub.2R.sup.6, OC.sub.6-10aryl, OC.sub.5-10heterocyclyl,
CH.sub.2OC.sub.1-6 alkyl, CH.sub.2SC.sub.1-6 alkyl, CH.sub.2Oaryl,
CH.sub.2Saryl; represents a double or single bond; p represents
0-3; n represents 0-4; and m represents 0-8.
2. A compound in accordance with claim 1 wherein R.sup.1 is
(CH.sub.2).sub.pCN, (CH.sub.2).sub.pCO.sub.2R.sup.10,
--(CH.sub.2).sub.pPO(OH).sub.2,
(CH.sub.2).sub.pCONHPO.sub.2R.sup.6, (CH.sub.2).sub.pCONHR.sup.8,
or (CH.sub.2).sub.nheterocyclyl, said heterocyclyl unsubstituted or
substituted with 1 to 3 groups of R.sup.a and all other variables
are as originally described.
3. A compound in accordance with claim 2 wherein Z is a bond or S,
Y is CH.sub.2 and X is O.[., S or CH.sub.2.]..
4. A compound in accordance with claim 1 wherein R.sup.1 is
(CH.sub.2).sub.pCO.sub.2R.sup.10, X is O, Y .[.are.]. .Iadd.is
.Iaddend.CH.sub.2, Z is (C(R.sup.b).sub.2).sub.n, Q is (CH.sub.2)m,
.Iadd.and .Iaddend.R.sup.2 is (CH.sub.2).sub.mC.sub.6-10aryl, said
aryl unsubstituted or substituted with 1 to 3 groups of
R.sup.a.
5. A compound in accordance with claim 2 wherein R.sup.1 is
(CH.sub.2).sub.mC.sub.5-10heterocyclyl, U is H, or C.sub.1-3 alkyl,
W is OH, Z is a bond or S, R.sup.2 is
(CH.sub.2).sub.mC.sub.6-10aryl, said aryl unsubstituted or
substituted with 1 to 3 groups of R.sup.a, said heterocyclyl
unsubstituted or substituted with 1 to 3 groups of R.sup.a and all
other variables are as originally described.
6. A compound which is:
7-{(4S)-4-[(3R)-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-oxazinan-3-yl}heptanoi-
c acid;
5-(3-{(4R)-4-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-oxaz-
inan-3-yl}propyl)thiophene-2-carboxylic acid; isopropyl
5-(3-{(4R)-4-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-oxazinan-3--
yl}propyl)thiophene-2-carboxylate;
.Iadd.7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-
-1,3-oxazinan-3-yl}heptanoic acid;
7-{(4S)-4-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-oxazinan--
3-yl}heptanoic acid; isopropyl
7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-o-
xazinan-3-yl}heptanoate;
(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-3-[6-(2H-tetra-
azol-5-yl)hexyl]-1,3-oxazinan-2-one;
5-(3-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,-
3-oxazinan-3-yl}propyl)thiophene-2-carboxylic acid;
(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-3-{3-[5-(2H-te-
traazol-5-yl)thien-2-yl]propyl}-1,3-oxazinan-2-one;
(4S)-4-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-3-{3-[5-(2H-tetraazol--
5-yl)thien-2-yl]propyl}-1,3-oxazinan-2-one; isopropyl
5-(3-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,-
3-oxazinan-3-yl}propyl)thiophene-2-carboxylate;
(5E)-7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo--
1,3-oxazinan-3-yl}hept-5-enoic acid;
(5E)-7-{(4S)-4-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-oxaz-
inan-3-yl}hept-5-enoic acid;
Isopropyl-7-{(4R)-4-[(1E)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-yl]-2-o-
xo-1,3-oxanzinan-3-yl}heptanoate;
7-{(4R)-4-[(1E)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-yl]-2-oxo-1,3-oxa-
nzinan-3-yl}heptanoic acid;.Iaddend. or a pharmaceutically
acceptable salt, enantiomer, diastereomer, .[.prodrug.]. or mixture
thereof.
7. A pharmaceutical composition comprising a pharmaceutically
acceptable carrier and a compound of formula I, as recited in claim
1.
8. A method for treating ocular hypertension or glaucoma comprising
administration to a patient in need of such treatment a
therapeutically effective amount of a compound of claim 1, said
compound administered in a topical formulation as a solution or
suspension.
9. A method for treating macular edema or macular degeneration,
treating dry eye, increasing retinal and optic nerve head blood
velocity, increasing retinal and optic nerve oxygen tension,
comprising administration to a patient in need of such treatment a
pharmaceutically effective amount of a compound of a compound as
recited in claim 1.
10. The method according to claim 9 in which the topical
formulation optionally contains xanthan gum or gellan gum.
.Iadd.11. A pharmaceutical composition comprising a
pharmaceutically acceptable carrier and a compound of formula I, as
recited in claim 6..Iaddend.
.Iadd.12. The compound according to claim 6 which is:
7-{(4S)-4-[(3R)-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-oxazinan-3-yl}heptanoi-
c acid or a pharmaceutically acceptable salt, enantiomer,
diastereomer, or mixture thereof..Iaddend.
.Iadd.13. The compound according to claim 6 which is
5-(3-{(4R)-4-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-oxazinan-3--
yl}propyl)thiophene-2-carboxylic acid or a pharmaceutically
acceptable salt, enantiomer, diastereomer, or mixture
thereof..Iaddend.
.Iadd.14. The compound according to claim 6 which is isopropyl
5-(3-{(4R)-4-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-oxazinan-3--
yl}propyl)thiophene-2-carboxylate or a pharmaceutically acceptable
salt, enantiomer, diastereomer, or mixture thereof..Iaddend.
.Iadd.15. The compound according to claim 6 which is
7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-o-
xazinan-3-yl}heptanoic acid;
7-{(4S)-4-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-oxazinan--
3-yl}heptanoic acid or a pharmaceutically acceptable salt,
enantiomer, diastereomer, or mixture thereof..Iaddend.
.Iadd.16. The compound according to claim 6 which is isopropyl
7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-o-
xazinan-3-yl}heptanoate or a pharmaceutically acceptable salt,
enantiomer, diastereomer, or mixture thereof..Iaddend.
.Iadd.17. The compound according to claim 6 which is
(5E)-7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo--
1,3-oxazinan-3-yl}hept-5-enoic acid or a pharmaceutically
acceptable salt, enantiomer, diastereomer, or mixture
thereof..Iaddend.
.Iadd.18. The compound according to claim 6 which is
(5E)-7-{(4S)-4-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-oxaz-
inan-3-yl}hept-5-enoic acid or a pharmaceutically acceptable salt,
enantiomer, diastereomer, or mixture thereof..Iaddend.
.Iadd.19. The compound according to claim 6 which is
Isopropyl-7-{(4R)-4-[(1E)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-yl]-2-o-
xo-1,3-oxanzinan-3-yl}heptanoate or a pharmaceutically acceptable
salt, enantiomer, diastereomer, or mixture thereof..Iaddend.
.Iadd.20. The compound according to claim 6 which is
7-{(4R)-4-[(1E)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-yl]-2-oxo-1,3-oxa-
nzinan-3-yl}heptanoic acid or a pharmaceutically acceptable salt,
enantiomer, diastereomer, or mixture thereof..Iaddend.
Description
BACKGROUND OF THE INVENTION
Glaucoma is a degenerative disease of the eye wherein the
intraocular pressure is too high to permit normal eye function. As
a result, damage may occur to the optic nerve head and result in
irreversible loss of visual function. If untreated, glaucoma may
eventually lead to blindness. Ocular hypertension, i.e., the
condition of elevated intraocular pressure without optic nerve head
damage or characteristic glaucomatous visual field defects, is now
believed by the majority of ophthalmologists to represent merely
the earliest phase in the onset of glaucoma.
Many of the drugs formerly used to treat glaucoma proved
unsatisfactory. Current methods of treating glaucoma include using
therapeutic agents such as pilocarpine, carbonic anhydrase
inhibitors, beta-blockers, prostaglandins and the like. However,
these therapies often produce undesirable local effects. As can be
seen, there are several current therapies for treating glaucoma and
elevated intraocular pressure, but the efficacy and the side effect
profiles of these agents are not ideal. Therefore, there still
exists the need for new and elective therapies with little or no
side effects.
A variety of disorders in humans and other mammals involve or are
associated with abnormal or excessive bone loss. Such disorders
include, but are not limited to, osteoporosis, glucocorticoid
induced osteoporosis, Paget's disease, abnormally increased bone
turnover, periodontal disease, tooth loss, bone fractures,
rheumatoid arthritis, periprosthetic osteolysis, osteogenesis
imperfecta, metastatic bone disease, hypercalcemia of malignancy,
and multiple myeloma. One of the most common of these disorders is
osteoporosis, which in its most frequent manifestation occurs in
postmenopausal women. Prostaglandins such as the PGE.sub.2 series
are known to stimulate bone formation and increase bone mass in
mammals, including man. It is believed that the four different
receptor subtypes, designated EP.sub.1, EP.sub.2, EP.sub.3, and
EP.sub.4 are involved in mediating the bone modeling and remodeling
processes of the osteoblasts and osteoclasts. The major
prostaglandin receptor in bone is EP.sub.4, which is believed to
provide its effect by signaling via cyclic AMP. In the present
invention it is found that the formula I agonists of the EP.sub.4
subtype receptor are useful for stimulating bone formation. WO
02/24647, WO 02/42268, EP 1114816, WO 01/46140 and WO 01/72268
disclose EP.sub.4 agonists. However, they do not disclose the
compounds of the instant invention.
SUMMARY OF THE INVENTION
This invention relates to agonists of the EP.sub.4 subtype of
prostaglandin E2 receptors and their use or a formulation thereof
in the treatment of glaucoma and other conditions that are related
to elevated intraocular pressure in the eye of a patient. In
particular, this invention relates to a series of 1,6-disubstituted
piperidin-2-one, 3,4-disubstituted 1,3-oxazinan-2-one,
3,4-disubstituted 1,3-thiazinan-2-one, and 4,5-disubstituted
morpholin-3-one derivatives and their use to treat ocular diseases
and to provide a neuroprotective effect to the eye of mammalian
species, particularly humans. This invention further relates to the
use of the compounds of this invention for mediating the bone
modeling and remodeling processes of the osteoblasts and
osteoclasts.
More particularly, this invention relates to novel EP4 agonist
having the structural formula I:
##STR00001## or a pharmaceutically acceptable salt, enantiomer,
diastereomer, prodrug or mixture thereof, wherein, Q is
(CH.sub.2).sub.m, (CH.sub.2).sub.mC.sub.6-10aryl,
(CH.sub.2).sub.mC.sub.5-10 heterocyclyl, (CH.sub.2).sub.mC.sub.3-10
heterocycloalkyl, (CH.sub.2).sub.mC.sub.3-8 cycloalkyl,
C(halo).sub.2 said cycloalkyl, heterocycloalkyl, aryl or
heterocyclyl unsubstituted or substituted with 1-3 groups of
R.sup.a; X and Y independently represent CH.sub.2, O, NR.sup.9 or
S, provided however, that X and Y are not O, NR.sup.9 or S at the
same time; U represents H, C1-3 alkyl or is not present when W is
.dbd.O; W represents OH or .dbd.O, provided that U is not present
when W is .dbd.O; R.sup.1 represents (CH.sub.2).sub.phydroxy,
(CH.sub.2).sub.pCN, (CH.sub.2).sub.pCO.sub.2R.sup.10,
(CH.sub.2).sub.nSO.sub.3R.sup.6,
--(CH.sub.2).sub.pCF.sub.2SO.sub.2NH.sub.2,
--(CH.sub.2).sub.pSO.sub.2NH.sub.2,
--(CH.sub.2).sub.pCONHSO.sub.2R.sub.2,
--(CH.sub.2).sub.pSO.sub.2NHCOR.sup.2,
--(CH.sub.2).sub.pPO(OH).sub.2,
(CH.sub.2).sub.pCONHPO.sub.2R.sup.6, (CH.sub.2).sub.pCONHR.sup.8,
(CH.sub.2).sub.pC.sub.1-4alkoxy, --(CH.sub.2).sub.pcycloalkyl,
(CH.sub.2).sub.p-hydroxymethylketone or
(CH.sub.2).sub.nheterocyclyl, said heterocyclyl unsubstituted or
substituted with 1 to 3 groups of R.sup.a and optionally containing
an acidic hydroxyl group; R.sup.2 independently represents
C.sub.1-10 alkyl, (CH.sub.2).sub.mC.sub.6-10aryl,
(CH.sub.2).sub.mC.sub.5-10heterocyclyl, (CH.sub.2).sub.mC.sub.3-10
heterocycloalkyl, (CH.sub.2).sub.mC.sub.3-8 cycloalkyl,
O--C.sub.1-10alkyl, O--C.sub.6-10aryl, O--C.sub.3-10cycloalkyl,
O--C.sub.3-10 heterocycloalkyl, O--C.sub.3-10 heterocycloalkyl,
provided that when R.sup.2 is O--C.sub.1-10alkyl,
O--C.sub.6-10aryl, O--C.sub.3-10cycloalkyl,
O--C.sub.3-10heterocycloalkyl, or O--C.sub.3-10 heterocycloalkyl,
R.sup.3 and R.sup.4 are not halogen, said alkyl, cycloalkyl,
heterocycloalkyl, aryl or heterocyclyl unsubstituted or substituted
with 1-3 groups of R.sup.a; R.sup.3 and R.sup.4 independently
represents hydrogen, halogen, or C.sub.1-6 alkyl, or R.sup.3 and
R.sup.4 may be taken together to form a 3-7 membered carbon ring
optionally interrupted with 1-2 heteroatoms chosen from O, S, SO,
SO.sub.2, and NR.sup.9; R.sup.6 and R.sup.7 independently
represents hydrogen, or C.sub.1-4 alkyl; R.sup.8 represents
hydrogen, acyl, or sulfonyl; R.sup.9 represents hydrogen, C.sub.1-6
alkyl, said alkyl optionally substituted with 1-3 halogen, CN, OH,
C.sub.1-6 alkoxy, C.sub.1-6 acyloxy or amino; R.sup.10 represents
hydrogen, C.sub.1-10 alkyl, C.sub.3-10 cyclcoalkyl,
(CH.sub.2).sub.pC.sub.6-10 aryl, (CH.sub.2).sub.pC.sub.5-10
heterocyclyl, CR.sup.6R.sup.7OC(O)O C.sub.3-10 cycloalkyl or
CR.sup.6R.sup.7OC(O)O C.sub.1-10 alkyl; Z represents a triple bond,
O, S, (C(R.sup.b).sub.2).sub.n, or Ch=CH; R.sup.b represents
hydrogen, C1-6 alkyl or halogen; R.sup.a represents C.sub.1-6
alkoxy, C.sub.1-6 alkyl, CF.sub.3, nitro, amino, cyano, C.sub.1-6
alkylamino, halogen, or Ra further represents for aryls and
heterocyclyl, SC.sub.1-6alkyl, SC.sub.6-10aryl,
SC.sub.5-10heterocyclyl, CO.sub.2R.sup.6, OC.sub.6-10aryl,
OC.sub.5-10heterocyclyl, CH.sub.2OC.sub.1-6 alkyl,
CH.sub.2SC.sub.1-6 alkyl, CH.sub.2Oaryl, CH.sub.2Saryl; represents
a double or single bonds; p represents 0-3; n represents 0-4; and m
represents 0-8.
This and other aspects of the invention will be realized upon
inspection of the invention as a whole.
DETAILED DESCRIPTION OF THE INVENTION
The invention is described herein in detail using the terms defined
below unless otherwise specified.
The term "therapeutically effective amount", as used herein, means
that amount of the EP.sub.4 receptor subtype agonist of formula I,
or other actives of the present invention, that will elicit the
desired therapeutic effect or response or provide the desired
benefit when administered in accordance with the desired treatment
regimen. A preferred therapeutically effective amount relating to
the treatment of abnormal bone resorption is a bone formation,
stimulating amount. Likewise, a preferred therapeutically effective
amount relating to the treatment of ocular hypertension or glaucoma
is an amount effective for reducing intraocular pressure and/or
treating ocular hypertension and/or glaucoma.
"Pharmaceutically acceptable" as used herein, means generally
suitable for administration to a mammal, including humans, from a
toxicity or safety standpoint.
The term "prodrug" refers to compounds which are drug precursors
which, following administration and absorption, release the claimed
drug in vivo via some metabolic process. A non-limiting example of
a prodrug of the compounds of this invention would be an acid of
the pyrrolidinone group, where the acid functionality has a
structure that makes it easily hydrolyzed after administration to a
patient. Exemplary prodrugs include acetic acid derivatives that
are non-narcotic, analgesics/non-steroidal, anti-inflammatory drugs
having a free CH.sub.2COOH group (which can optionally be in the
form of a pharmaceutically acceptable salt, e.g.
--CH.sub.2COO--Na+), typically attached to a ring system,
preferably to an aromatic or heteroaromatic ring system.
The term "alkyl" refers to a monovalent alkane (hydrocarbon)
derived radical containing from 1 to 10 carbon atoms unless
otherwise defined. It may be straight, branched or cyclic.
Preferred alkyl groups include methyl, ethyl, propyl, isopropyl,
butyl, t-butyl, cyclopentyl and cyclohexyl. When the alkyl group is
said to be substituted with an alkyl group, this is used
interchangeably with "branched alkyl group".
Cycloalkyl is a species of alkyl containing from 3 to 15 carbon
atoms, without alternating or resonating double bonds between
carbon atoms. It may contain from 1 to 4 rings, which are fused.
Examples of cycloalkyl groups are cyclopropyl, cyclobutyl,
cyclopentyl, cyclohexyl, and cycloheptyl.
Alkoxy refers to C.sub.1-C.sub.6 alkyl-O-, with the alkyl group
optionally substituted as described herein. Examples of alkoxy
groups are methoxy, ethoxy, propoxy, butoxy and isomeric groups
thereof.
Halogen (halo) refers to chlorine, fluorine, iodine or bromine.
Aryl refers to aromatic rings e.g., phenyl, substituted phenyl and
the like, as well as rings which are fused, e.g., naphthyl,
phenanthrenyl and the like. An aryl group thus contains at least
one ring having at least 6 atoms, with up to five such rings being
present, containing up to 22 atoms therein, with alternating
(resonating) double bonds between adjacent carbon atoms or suitable
heteroatoms. The preferred aryl groups are phenyl, naphthyl and
phenanthrenyl. Aryl groups may likewise be substituted as defined.
Preferred substituted aryls include phenyl and naphthyl.
The term "heterocycloalkyl" refers to a cycloalkyl group
(nonaromatic) having 3 to 10 carbon atoms in which one of the
carbon atoms in the ring is replaced by a heteroatom selected from
O, S or N and in which up to three additional carbon atoms may be
replaced by hetero atoms.
The term "cycloalkyl" refers to a cyclic alkyl group (nonaromatic)
having 3 to 10 carbon atoms.
The term "heteroatom" means O, S or N, selected on an independent
basis.
The term "heteroaryl" refers to a monocyclic aromatic hydrocarbon
group having 5 or 6 ring atoms, or a bicyclic aromatic group having
8 to 10 atoms, containing at least one heteroatom, O, S or N, in
which a carbon or nitrogen atom is the point of attachment, and in
which one or two additional carbon atoms is optionally replaced by
a heteroatom selected from O or S, and in which from 1 to 3
additional carbon atoms are optionally replaced by nitrogen
heteroatoms, said heteroaryl group being optionally substituted as
described herein. Examples of this type are pyrrole, pyridine,
oxazole, thiazole, tetrazole, and oxazine. For purposes of this
invention the tetrazole includes all tautomeric forms. Additional
nitrogen atoms may be present together with the first nitrogen and
oxygen or sulfur, giving, e.g., thiadiazole.
The term heterocyclyl or heterocyclic, as used herein, represents a
stable 5- to 7-membered monocyclic or stable 8- to 11-membered
bicyclic heterocyclic ring which is either saturated or
unsaturated, and which consists of carbon atoms and from one to
four heteroatoms selected from the group consisting of N, O, and S,
and including any bicyclic group in which any of the above-defined
heterocyclic rings is fused to a benzene ring. The heterocyclic
ring may be attached at any heteroatom or carbon atom, which
results in the creation of a stable structure. A fused heterocyclic
ring system may include carbocyclic rings and need include only one
heterocyclic ring. The term heterocycle or heterocyclic includes
heteroaryl moieties. Examples of such heterocyclic elements
include, but are not limited to, azepinyl, benzimidazolyl,
benzisoxazolyl, benzofurazanyl, benzopyranyl, benzothiopyranyl,
benzofuryl, benzothiazolyl, benzothienyl, benzoxazolyl, chromanyl,
cinnolinyl, dihydrobenzofuryl, dihydrobenzothienyl,
dihydrobenzothiopyranyl, dihydrobenzothiopyranyl sulfone,
1,3-dioxolanyl, furyl, imidazolidinyl, imidazolinyl, imidazolyl,
indolinyl, indolyl, isochromanyl, isoindolinyl, isoquinolinyl,
isothiazolidinyl, isothiazolyl, isothiazolidinyl, morpholinyl,
naphthyridinyl, oxadiazolyl, 2-oxoazepinyl, oxazolyl,
2-oxopiperazinyl, 2-oxopiperdinyl, 2-oxopyrrolidinyl, piperidyl,
piperazinyl, pyridyl, pyrazinyl, pyrazolidinyl, pyrazolyl,
pyridazinyl, pyrimidinyl, pyrrolidinyl, pyrrolyl, quinazolinyl,
quinolinyl, quinoxalinyl, tetrahydrofuryl, tetrahydroisoquinolinyl,
tetrahydroquinolinyl, tetrazolyl, thiamorpholinyl, thiamorpholinyl
sulfoxide, thiazolyl, thiazolinyl, thienofuryl, thienothienyl,
thienyl, and triazolyl.
For purposes of this invention, heterocyclyls containing acidic
hydroxyl groups are those heterocyclyl groups that have an acidic
hydroxy atom and can have a pKa in the range of 3 to 7.
Non-limiting examples of heterocyclyls containing acidic hydroxyl
groups are:
##STR00002## --N(R.sup.e).sub.2, O, or S and each R.sup.c
independently is H, fluorine, cyano or C.sub.1-4 alkyl; each
R.sup.d independently is H, C.sub.1-4 alkyl, or a pharmaceutically
acceptable cation; each R.sup.e independently is H,
--C(.dbd.O)--R.sup.f, or --SO.sub.2R.sup.e, wherein R.sup.f is
C.sub.1-4 linear alkyl or phenyl
The term "agonist" as used herein means EP.sub.4 subtype compounds
of formula I interact with the EP4 receptor to produce maximal,
super maximal or submaximal effects compared to the natural
agonist, PGE2. See Goodman and Gilman, The Pharmacological Basis of
Therapeutics, 9th edition, 1996, chapter 2.
One embodiment of this invention is realized when R.sup.1 is
(CH.sub.2).sub.pCN, (CH.sub.2).sub.pCO.sub.2R.sup.10,
--(CH.sub.2).sub.pPO(OH).sub.2,
(CH.sub.2).sub.pCONHPO.sub.2R.sup.6, (CH.sub.2).sub.pCONHR.sup.8,
or (CH.sub.2).sub.nheterocyclyl, said heterocyclyl unsubstituted or
substituted with 1 to 3 groups of R.sup.a and all other variables
are as originally described. A subembodiment of this invention is
realized when Z is a (C(R.sup.b).sub.2).sub.n. Another
subembodiment of this invention is when Z is Sulfur. When R.sup.1
is (CH.sub.2).sub.pCO.sub.2R.sup.10, and Z is sulfur, the sulfur is
hexavalent. Another embodiment of this invention is when Z is
O.
Another embodiment of this invention is realized when R.sup.1 is
(CH.sub.2).sub.pCO.sub.2R.sup.10 and all other variables are as
originally described. A subembodiment of this invention is realized
when X and Y are CH.sub.2, Z is (C(R.sup.b).sub.2).sub.n, Q is
(CH.sub.2).sub.m, R.sup.3 and R.sup.4 are halogen and all other
variables are as originally described.
Another embodiment of this invention is realized when R.sup.1 is
(CH.sub.2).sub.mC.sub.5-10heterocyclyl, said heterocyclyl
unsubstituted or substituted with 1 to 3 groups of R.sup.a and all
other variables are as originally described. A subembodiment of
this invention is realized when Z is a (C(R.sup.b).sub.2).sub.n.
Another subembodiment of this invention is realized when Z is S.
Another embodiment of this invention is when Z is O.
Another embodiment of this invention is realized when R.sup.2 is
(CH.sub.2).sub.mC.sub.6-10aryl, said an unsubstituted or
substituted with 1 to 3 groups of R.sup.a and all other variables
are as originally described.
A sub-embodiment of this invention is realized when R.sup.1 is
(CH.sub.2).sub.pCO.sub.2R.sup.10, --(CH.sub.2).sub.pPO(OH).sub.2,
(CH.sub.2).sub.pCONHPO.sub.2R.sup.6, (CH.sub.2).sub.pCONHR.sup.8,
or (CH.sub.2).sub.p-tetrazolyl said tetrazolyl unsubstituted or
substituted with a R.sub.a group and all other variables are as
originally described. A subembodiment of this invention is realized
when Z is a (C(R.sup.b).sub.2).sub.n. Another subembodiment of this
invention is realized when Z is S. Another embodiment of this
invention is when Z is O.
Still another embodiment of this invention is realized when R.sup.2
is a phenyl unsubstituted or substituted with 1 to 3 groups of
R.sup.a and all other variables are as originally described.
Yet another embodiment of this invention is realized when R.sup.1
is (CH.sub.2).sub.p-tetrazolyl and R.sup.2 is phenyl, said
tetrazolyl unsubstituted or substituted with an R.sup.a group and
phenyl is unsubstituted or substituted with 1-3 groups of R.sup.a,
and all other variables are as originally described. A
subembodiment of this invention is realized when Z is a
(C(R.sup.b).sub.2).sub.n. Another subembodiment of this invention
is realized when Z is S. Another embodiment of this invention is
when Z is O.
Still another embodiment of this invention is realized when U is H
and W is OH.
Still another embodiment of this invention is realized when U is
C1-3 alkyl and W is OH.
Still another embodiment of this invention is realized when Q
represents (CH.sub.2).sub.n, or C(halo).sub.2 and all other
variables are as originally described. A subembodiment of this
invention is realized when Z is a (C(R.sup.b).sub.2).sub.n. Another
subembodiment is realized when Z is S. Still another subembodiment
is realized when Z is O
Still another embodiment of this invention is realized when Y
represents CH.sub.2, X is O, S or CH.sub.2, W is OH, U is H or
methyl, R.sup.3 is H, F or CH.sub.2 and R.sup.2 is phenyl, thienyl,
naphthyl, benzothioenyl, benzofuranyl, or biphenyl, said phenyl,
thienyl, naphthyl, benzothioenyl, benzofuranyl, or biphenyl
unsubstituted or substituted with 1-3 groups of R.sup.a and all
other variables are as originally described.
Compounds of this invention are:
7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopiperi-
din-1-yl}heptanoic acid;
7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-o-
xazinan-3-yl}heptanoic acid;
7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-t-
hiazinan-3-yl}heptanoic acid;
7-{(2R)-2-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-6-oxopiperidin-1-yl-
}heptanoic acid;
7-{(4S)-4-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-oxazinan--
3-yl}heptanoic acid;
7-{(4S)-4-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-thiazinan-
-3-yl}heptanoic acid;
7-{(2R)-2-[(3R)-3-hydroxy-4-phenylbutyl]-6-oxopiperidin-1-yl}heptanoic
acid;
7-{(4S)-4-[(3R)-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-oxazinan-3-yl}he-
ptanoic acid;
7-{(4S)-4-[(3R)-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-thiazinan-3-yl}heptano-
ic acid; isopropyl
7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopiperi-
din-1-yl}heptanoate; isopropyl
7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3ox-
azinan-3-yl}heptanoate; isopropyl
7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-t-
hiazinan-3-yl}heptanoate;
(6R)-6-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-1-[6-(2H-tetra-
azol-5-yl)hexyl]piperidin-2-one;
(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-3-[6-(2H-tetra-
azol-5-yl)hexyl]-1,3-oxazinan-2-one;
(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-3-[6-(2H-teraz-
ol-5-yl)hexyl]-1,3-thiazinan-2-one;
(5S)-5-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-4-[6-(2H-tetra-
azol-5-yl)hexyl]morpholin-3-one;
(6S)-6-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-1-[6-(2H-tetra-
azol-5-yl)hexyl]piperazin-2-one;
(5S)-5-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-4-[6-(2H-tetra-
azol-5-yl)hexyl]thiomorpholin-3-one;
5-(3-{(2R)-2-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-6-oxopiperidin-1-yl}p-
ropyl)thiophene-2-carboxylic acid;
5-(3-{(4R)-4-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-oxazinan-3--
yl}propyl)thiophene-2-carboxylic acid;
5-(3-{(4R)-4-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-thiazinan-3-
-yl}propyl)thiophene-2-carboxylic acid;
5-(3-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopip-
eridin-1-yl}propyl)thiophene-2-carboxylic acid;
5-(3-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,-
3-oxazinan-3-yl}propyl)thiophene-2-carboxylic acid;
5-(3-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,-
3-thiazinan-3-yl}propyl)thiophene-2-carboxylic acid;
(6R)-6-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-1-{3-[5-(2H-te-
traazol-5-yl)thien-2-yl]propyl}piperidin-2-one;
(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-3-{3-[5-(2H-te-
traazol-5-yl)thien-2-yl]propyl}-1,3-oxazinan-2-one;
(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-3-{3-[5-(2H-te-
traazol-5-yl)thien-2-yl]propyl}-1,3-thiazinan-2-one;
(6R)-6-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-1-{3-[5-(2H-tetraazol--
5-yl)thien-2-yl]propyl}piperidin-2-one;
(4S)-4-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-3-{3-[5-(2H-tetraazol--
5-yl)thien-2-yl]propyl}-1,3-oxazinan-2-one;
(4S)-4-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-3-{3-[5-(2H-tetraazol--
5-yl)thien-2-yl]propyl}-1,3-thiazinan-2-one; isopropyl
5-(3-{(2R)-2-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-6-oxopiperidin-1-yl}p-
ropyl)thiophene-2-carboxylate; isopropyl
5-(3-{(4R)-4-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-oxazinan-3--
yl}propyl)thiophene-2-carboxylate; isopropyl
5-(3-{(4R)-4-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-oxazinan-3--
yl}propyl)thiophene-2-carboxylate; isopropyl
5-(3-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopip-
eridin-1-yl}propyl)thiophene-2-carboxylate; isopropyl
5-(3-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,-
3-oxazinan-3-yl}propyl)thiophene-2-carboxylate; isopropyl
5-(3-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,-
3-thiazinan-3-yl}propyl)thiophene-2-carboxylate;
(5E)-7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxop-
iperidin-1-yl}hept-5-enoic acid;
(5E)-7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo--
1,3-oxazinan-3-yl}hept-5-enoic acid;
(5E)-7-{(4R)-4-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo--
1,3-thiazinan-3-yl}hept-5-enoic acid;
(5E)-7-{(2R)-2-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-6-oxopiperidin-
-1-yl}hept-5-enoic acid;
(5E)-7-{(4S)-4-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-oxaz-
inan-3-yl}hept-5-enoic acid;
(5E)-7-{(4S)-4-[(3R)-4,4-difluoro-3-hydroxy-4-phenylbutyl]-2-oxo-1,3-thia-
zinan-3-yl}hept-5-enoic acid;
2-(3-{(2R)-2-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-6-oxopiperidin-1-yl}p-
ropyl)-1,3-thiazole-5-carboxylic acid;
5-(3-{(2R)-2-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-6-oxopiperidin-1-yl}p-
ropyl)-1,3-thiazole-2-carboxylic acid;
5-(3-{(2R)-2-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-6-oxopiperidin-1-yl}p-
ropyl)-1,3-oxazole-2-carboxylic acid;
2-(3-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopip-
eridin-1yl}propyl)-1,3-oxazole-5-carboxylic acid;
5-(3-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopip-
eridin-1-yl}propyl)-1H-imidazole-2-carboxylic acid;
2-(3-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopip-
eridin-1-yl}propyl)-1H-imidazole-5-carboxylic acid;
2-(3-{(2R)-2-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-6-oxopiperidin-1yl}pr-
opyl)-1,3-oxazole-5-carboxylic acid;
5-(3-{(2R)-2-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-6-oxopiperidin-1yl}pr-
opyl)-1,2.lamda..sup.5, 5.lamda..sup.5-oxadiazole-2-carboxylic
acid;
5-(3-{(2R)-2-[(1E,3S)-3-hydroxy-4-phenylbut-1-enyl]-6-oxopiperidin-1-yl}p-
ropyl)-4H-1,2,4-triazole-3-carboxylic acid;
5-((1E)-3-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-o-
xopiperidin-1-yl}prop-1-enyl)thiophene-2-carboxylic acid;
5-(3-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopip-
eridin-1-yl}prop-1-ynyl)thiophene-2-carboxylic acid;
5-((1Z)-3-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-o-
xopiperidin-1-yl}prop-1-enyl)thiophene-2-carboxylic acid;
(6R)-6-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-1-{(2Z)-4-[(1H-
-tetraazol-5-ylmethyl)thio]but-2-enyl}piperidin-2-one;
[(4-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopipe-
ridin-1-yl}but-2-ynyl)thio]acetic acid;
[((2Z)-4-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-ox-
opiperidin-1-yl}but-2-enyl)thio]acetic acid;
[(4-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopipe-
ridin-1-yl}butyl)thio]acetic acid;
(4-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopiper-
idin-1-yl}butoxy)acetic acid;
3-[(3-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-6-oxopi-
peridin-1-yl}propyl)thio]propanoic acid;
7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-3-methyl-4-phenylbut-1-enyl]-6--
oxopiperidin-1-yl}heptanoic acid;
7-{(2R)-2-[(1E,3S)-4,4-difluoro-3-hydroxy-3-methyl-4-phenylbut-1-enyl]-6--
oxopiperidin-1-yl}heptanoic acid;
7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-(2-naphthyl)but-1-enyl]-6-oxo-
piperidin-1-yl}heptanoic acid;
(6R)-6-[(1E,3R)-4,4-difluoro-3-hydroxy-3-methyl-4-phenylbut-1-enyl]-1-[6--
(1H-tetraazol-5-yl)hexyl]piperidin-2-one;
(6R)-6-[(1E,3S)-4,4-difluoro-3-hydroxy-3-methyl-4-phenylbut-1-enyl]-1-[6--
(1H-tetraazol-5-yl)hexyl]piperidin-2-one;
7-{(2R)-2-[(1E,3R)-4-(1-benzothien-2-yl)-4,4-difluoro-3-hydroxybut-1-enyl-
]-6-oxopiperidin-1-yl}heptanoic acid;
(6R)-6-[(3R)-4,4-difluoro-3-hydroxy-3-methyl-4-phenylbutyl]-1-[6-(1H-tetr-
aazol-5-yl)hexyl]piperidin-2-one;
(6R)-6-[(3S)-4,4-difluoro-3-hydroxy-3-methyl-4-phenylbutyl]-1-[6-(1H-tetr-
aazol-5-yl)hexyl]piperidin-2-one;
7-{(2R)-2-[(1E,3R)-4-(1-benzofuran-2-yl)-4,4-difluoro-3-hydroxybut-1-enyl-
]-6-oxopiperidin-1-yl}heptanoic acid;
7-{(2R)-2-[(1E,3R)-4-(3-chlorophenyl)-4,4-difluoro-3-hydroxybut-1-enyl]-6-
-oxopiperidin-1-yl}heptanoic acid;
7-{(2R)-2-[(1E,3R)-4-(3-chlorophenyl)-4,4-difluoro-3-hydroxybut-1-enyl]-6-
-oxopiperidin-1-yl}heptanoic acid;
7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-(3-methoxyphenyl)but-1-enyl]--
6-oxopiperidin-1-yl}heptanoic acid;
6-[(1E)-(3R)-3-hydroxy-4-phenyl-but-1-enyl]-1-[6-(1H-teraazol-5-yl)-hexyl-
]-piperidin-2-one;
7-{[(1E)-(2R)-2-(3S)-3-hydroxy-4-phenyl-but-1-enyl]-6-oxo-piperdin-1-yl}h-
eptanoic acid; isopropyl
7-{[(1E)-(2R)-2-(3S)-3-hydroxy-4-phenyl-but-1-enyl]-6-oxo-piperdin-1-yl}h-
eptanoate; isopropyl
7-{(2R)-2-[(3R)-3-hydroxy-4-phenyl-butyl]-6-oxo-piperdin-1-yl}heptanoate;
7-{[(2R)-2-(3R)-3-hydroxy-4-phenyl-butyl]-6-oxo-piperdin-1-yl}heptanoic
acid; methyl 5-{3-[(2R)-2-((1E)-(3S)
3-hydroxy-4-phenyl-but-1-enyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2--
carboxylate; 5-{3-[(2R)-2-((1E)-(3S)
3-hydroxy-4-phenyl-but-1-enyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2--
carboxylic acid; 5-{3-[(2R)-2-((3S)
3-hydroxy-4-phenyl-butyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2-carbo-
xylic acid; isopropyl 5-{3-[(2R)-2-((1E)-(3S)
3-hydroxy-4-phenyl-but-1-enyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2--
carboxylate; isopropyl 5-{3-[(2R)-2-((3S)
3-hydroxy-4-phenyl-butyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2-carbo-
xylate;
6-[(3R)-3-hydroxy-4-phenyl-butyl]-1-[6-(1H-teraazol-5-yl)-hexyl]-p-
iperidin-2-one isopropyl
7-{(2R)-2-[(1E)-4,4-difluoro-3-oxo-4-phenylbut-1-enyl]-6-oxopiperidin-1-y-
l}heptanoate;
7-{(2R)-2-[(3R)-4-(3-bromophenyl)-4,4-difluoro-3-hydroxybutyl]-6-oxopiper-
idin-1-yl}heptanoic acid; methyl 5-{3-[(2R)-2-((1E)-(3S)
3-hydroxy-4-phenyl-but-1-enyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2--
carboxylate; 5-{3-[(2R)-2-((3S)
3-hydroxy-4-phenyl-butyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2-carbo-
xylic acid; isopropyl 5-{3-[(2R)-2-((3S)
3-hydroxy-4-phenyl-butyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2-carbo-
xylate;
6-[(3R)-3-hydroxy-4-phenyl-butyl]-1-[6-(1H-teraazol-5-yl)-hexyl]-p-
iperidin-2-one; isopropyl
(5Z)-7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-1-yl]-6-o-
xopiperidin-1-yl}hept-5-enoate;
(5Z)-7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-1-yl]-6-o-
xopiperidin-1-yl}hept-5-enoic acid;
isopropyl-7-{(4R)-4-[(1E)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-yl]-2-o-
xo-1,3oxanzinan-3-yl}heptanoate;
7-{(4R)-4-[(1E)-4,4-difluoro-3-hydroxy-4-phenylbut-1-enyl]-2-oxo-1,3-oxan-
zinan-3-yl}heptanoic acid; or a pharmaceutically acceptable salt,
enantiomer, diastereomer, prodrug or mixture thereof.
Another embodiment of this invention is directed to a composition
containing an EP.sub.4 agonist of Formula I and optionally a
pharmaceutically acceptable carrier.
Yet another embodiment of this invention is directed to a method
for decreasing elevated intraocular pressure or treating glaucoma
by administration, preferably topical or intracamaral
administration, of a composition containing an EP.sub.4 agonist of
Formula I and optionally a pharmaceutically acceptable carrier. Use
of the compounds of formula I for the manufacture of a medicament
for treating elevated intraocular pressure or glaucoma or a
combination thereof is also included in this invention
This invention is further concerned with a process for making a
pharmaceutical composition comprising a compound of formula I.
This invention is further concerned with a process for making a
pharmaceutical composition comprising a compound of formula I, and
a pharmaceutically acceptable carrier.
The claimed compounds bind strongly and act on PGE.sub.2 receptor,
particularly on the EP.sub.4 subtype receptor and therefore are
useful for preventing and/or treating glaucoma and ocular
hypertension.
Dry eye is a common ocular surface disease afflicting millions of
people. Although it appears that dry eye may result from a number
of unrelated pathogenic causes, the common end result is the
breakdown of the tear film, which results in dehydration of the
exposed outer surface of the eye. (Lemp, Report of the Nation Eye
Institute/Industry Workshop on Clinical Trials in Dry Eyes, The
CLAO Journel, 21(4):221-231 (1995)). Functional EP4 receptors have
been found in human conjuctival epithelial cells (see U.S. Pat. No.
6,344,477, incorporated by reference in its entirey) and it is
appreciated that both human corneal epithelial cells (Progess in
Retinal and Eye Research, 16:81-98(1997)) and conjuctival cells
(Dartt et al. Localization of nerves adjacent to goblet cells in
rat conjucntiva. Current Eye Research, 14:993- 1000 (1995)) are
capable of secreting mucins. Thus, the compounds of formula I are
useful for treating dry eye.
Macular edema is swelling within the retina within the critically
important central visual zone at the posterior pole of the eye. It
is believed that EP.sub.4 agonist which lower IOP are useful for
treating diseases of the macular such as macular edema or macular
degeneration. Thus, another aspect of this invention is a method
for treating macular edema or macular degeneration.
Glaucoma is characterized by progressive atrophy of the optic nerve
and is frequently associated with elevated intraocular pressure
(IOP). It is possible to treat glaucoma, however, without
necessarily affecting IOP by using drugs that impart a
neuroprotective effect. See Arch. Ophthalmol. Vol. 112, January
1994, pp. 37-44; Investigative Ophthamol. & Visual Science, 32,
5, Apr. 1991, pp. 1593-99. It is believed that EP.sub.4 agonist
which lower IOP are useful for providing a neuroprotective effect.
They are also believed to be effective for increasing retinal and
optic nerve head blood velocity and increasing retinal and optic
nerve oxygen by lowering IOP, which when coupled together benefits
optic nerve health. As a result, this invention further relates to
a method for increasing retinal and optic nerve head blood
velocity, or increasing retinal and optic nerve oxygen tension or
providing a neuroprotective effect or a combination thereof by
using an EP.sub.4 agonist of formula I.
The compounds produced in the present invention are readily
combined with suitable and known pharmaceutically acceptable
excipients to produce compositions which may be administered to
mammals, including humans, to achieve effective IOP lowering. Thus,
this invention is also concerned with compositions and methods of
treating ocular hypertension, glaucoma, macular edema, macular
degeneration, for increasing retinal and optic nerve head blood
velocity, for increasing retinal and optic nerve oxygen tension,
for providing a neuroprotective effect or for a combination thereof
by administering to a patient in need thereof one of the compounds
of formula I alone or in combination with one or more of the
following active ingredients, a .beta.-adrenergic blocking agent
such as timolol, betaxolol, levobetaxolol, carteolol, levobunolol,
a parasympathomimetic agent such as pilocarpine, a sympathomimetic
agents such as epinephrine, iopidine, brimonidine, clonidine,
para-aminoclonidine, a carbonic anhydrase inhibitor such as
dorzolamide, acetazolamide, metazolamide or brinzolamide;
COSOPT.RTM., a Maxi-K channel blocker such as Penitrem A,
paspalicine, charybdotoxin, iberiotoxin, Paxicillan, Aflitram,
Verroculogen, and as disclosed in WO 03/105868 (U.S. Ser. No.
60/389,205), WO 03/105724 (60/389,222), WO 03/105847 (60/458,981),
60/424,790, filed Nov. 8, 2002, 60/424,808, filed Nov. 8, 2002,
Ser. No. 09/765,716, filed Jan. 17, 2001, Ser. No. 09/764,738,
filed Jan. 17, 2001 and PCT publications WO 02/077168 and WO
02/02060863, all incorporated by reference in their entirety
herein, and in particular Maxi-K channel blockers such as
1-(1-isobutyl-6-methoxy-1H-indazol-3-yl)-2-methylpropan-1-one;
1-[1-(2,2-dimethylpropyl)-6-methoxy-1H-indazol-3-yl]-2-methylpropan-1-one-
;
1-[1-(cyclohexylmethyl)-6-methoxy-1H-indazol-3-yl]-2-methylpropan-1-one;
1-(1-hexyl-6-methoxy-1H-indazol-3-yl)-2-methylpropan-1-one;
1-[1-(2-ethylhexyl)-6-methoxy-1H-indazol-3-yl]-2-methylpropan-1-one;
1-(3-isobutyryl-6-methoxy-1H-indazol-1-yl)buan-2-one;
1-(3-isobutyryl-6-methoxy-1H-indazol-1-yl)-3,3-dimethylbutan-2-one;
1-(3-cyclopentylcarbonyl)-6-methoxy-1H-indazol-1-yl)-3,3-dimethylbutan-2--
one; 1-(3,3-dimethyl-2-oxobutyl)-6-methoxy-1H-indazole-3-carboxylic
acid; and
1-[3-(3-hydroxypropanoyl)-6-methoxy-1H-indazol-1-yl]-3,3-dimethylbuta-
n-2-one, a prostaglandin such as latanoprost, travaprost,
unoprostone, rescula, S1033 (compounds set forth in U.S. Pat. Nos.
5,889,052; 5,296,504; 5,422,368; and 5,151,444); a hypotensive
lipid such as lumigan and the compounds set forth in U.S. Pat. No.
5,352,708; a neuroprotectant disclosed in U.S. Pat. No. 4,690,931,
particularly eliprodil and R-eliprodil as set forth in WO 94/13275,
including memantine; and/or an agonist of 5-HT2 receptors as set
forth in PCT/US00/31247, particularly
1-(2-aminopropyl)-3-methyl-1H-imdazol-6-ol fumarate and
2-(3-chloro-6-methoxy-indazol-1-yl)-1-methyl-ethylamine.
Use of the compounds of formula I for the manufacture of a
medicament for treating ocular hypertension, glaucoma, macular
edema, macular degeneration, for increasing retinal and optic nerve
head blood velocity, for increasing retinal and optic nerve oxygen
tension, for providing a neuroprotective effect or for a
combination thereof is also included in this invention.
The EP.sub.4 agonist used in the instant invention can be
administered in a therapeutically effective amount intravaneously,
subcutaneously, topically, transdermally, parenterally or any other
method known to those skilled in the art. Ophthalmic pharmaceutical
compositions are preferably adapted for topical administration to
the eye in the form of solutions, suspensions, ointments, creams or
as a solid insert. Ophthalmic formulations of this compound may
contain from 0.001 to 5% and especially 0.001 to 0.1% of
medicament. Higher dosages as, for example, up to about 10% or
lower dosages can be employed provided the dose is effective in
reducing intraocular pressure, treating glaucoma, increasing blood
flow velocity or oxygen tension. For a single dose, from between
0.001 to 5.0 mg, preferably 0.005 to 2.0 mg, and especially 0.005
to 1.0 mg of the compound can be applied to the human eye.
The pharmaceutical preparation which contains the compound may be
conveniently admixed with a non-toxic pharmaceutical organic
carrier, or with a non-toxic pharmaceutical inorganic carrier.
Typical of pharmaceutically acceptable carriers are, for example,
water, mixtures of water and water-miscible solvents such as lower
alkanols or aralkanols, vegetable oils, peanut oil, polyalkylene
glycols, petroleum based jelly, ethyl cellulose, ethyl oleate,
carboxymethyl-cellulose, polyvinylpyrrolidone, isopropyl myristate
and other conventionally employed acceptable carriers. The
pharmaceutical preparation may also contain non-toxic auxiliary
substances such as emulsifying, preserving, wetting agents, bodying
agents and the like, as for example, polyethylene glycols 200, 300,
400 and 600, carbowaxes 1,000, 1,500, 4,000, 6,000 and 10,000,
antibacterial components such as quaternary ammonium compounds,
phenylmercuric salts known to have cold sterilizing properties and
which are non-injurious in use, thimerosal, methyl and propyl
paraben, benzyl alcohol, phenyl ethanol, buffering ingredients such
as sodium borate, sodium acetates, gluconate buffers, and other
conventional ingredients such as sorbitan monolaurate,
triethanolamine, oleate, polyoxyethylene sorbitan monopalmitylate,
dioctyl sodium sulfosuccinate, monothioglycerol, thiosorbitol,
ethylenediamine tetracetic acid, and the like. Additionally,
suitable ophthalmic vehicles can be used as carrier media for the
present purpose including conventional phosphate buffer vehicle
systems, isotonic boric acid vehicles, isotonic sodium chloride
vehicles, isotonic sodium borate vehicles and the like. The
pharmaceutical preparation may also be in the form of a
microparticle formulation. The pharmaceutical preparation may also
be in the form of a solid insert. For example, one may use a solid
water soluble polymer as the carrier for the medicament. The
polymer used to form the insert may be any water soluble non-toxic
polymer, for example, cellulose derivatives such as
methylcellulose, sodium carboxymethyl cellulose, (hydroxyloweralkyl
cellulose), hydroxyethyl cellulose, hydroxypropyl cellulose,
hydroxypropylmethyl cellulose; acrylates such as polyacrylic acid
salts, ethylacrylates, polyactylamides; natural products such as
gelatin, alginates, pectins, tragacanth, karaya, chondrus, agar,
acacia; the starch derivatives such as starch acetate,
hydroxymethyl starch ethers, hydroxypropyl starch, as well as other
synthetic derivatives such as polyvinyl alcohol, polyvinyl
pyrrolidone, polyvinyl methyl ether, polyethylene oxide,
neutralized carbopol and xanthan gum, gellan gum, and mixtures of
said polymer.
Suitable subjects for the administration of the formulation of the
present invention include primates, man and other animals,
particularly man and domesticated animals such as cats, rabbits and
dogs.
The pharmaceutical preparation may contain non-toxic auxiliary
substances such as antibacterial components which are non-injurious
in use, for example, thimerosal, benzalkonium chloride, methyl and
propyl paraben, benzyldodecinium bromide, benzyl alcohol, or
phenylethanol; buffering ingredients such as sodium chloride,
sodium borate, sodium acetate, sodium citrate, or gluconate
buffers; and other conventional ingredients such as sorbitan
monolaurate, triethanolamine, polyoxyethylene sorbitan
monopalmitylate, ethylenediamine tetraacetic acid, and the
like.
The ophthalmic solution or suspension may be administered as often
as necessary to maintain an acceptable IOP level in the eye. It is
contemplated that administration to the mammalian eye will be from
once up to three times daily.
For topical ocular administration the novel formulations of this
invention may take the form of solutions, gels, ointments,
suspensions or solid inserts, formulated so that a unit dosage
comprises a therapeutically effective amount of the active
component or some multiple thereof in the case of a combination
therapy.
The compounds of the instant invention are also useful for
mediating the bone modeling and remodeling processes of the
osteoblasts and osteoclasts. See PCT US99/23757 filed Oct. 12, 1999
and incorporated herein by reference in its entirety. The major
prostaglandin receptor in bone is EP.sub.4, which is believed to
provide its effect by signaling via cyclic AMP. See Ikeda T,
Miyaura C, Ichikawa A, Narumiya S, Yoshiki S and Suda T 1995, In
situ localization of three subtypes (EP.sub.1, EP.sub.3 and
EP.sub.4) of prostaglandin E receptors in embryonic and newborn
mice., J Bone Miner Res 10 (sup 1):S172, which is incorporated by
reference herein in its entirety. Use of the compounds of formula I
for the manufacture of a medicament for mediating the bone modeling
and remodeling processes are also included in this invention.
Thus, another object of the present invention is to provide methods
for stimulating bone formation, i.e. osteogenesis, in a mammal
comprising administering to a mammal in need thereof a
therapeutically effective amount of an EP.sub.4 receptor subtype
agonist of formula I.
Still another object of the present invention to provide methods
for stimulating bone formation in a mammal in need thereof
comprising administering to said mammal a therapeutically effective
amount of an EP.sub.4 receptor subtype agonist of formula I and a
bisphosphonate active. Use of the compounds of formula I for the
manufacture of a medicament for stimulating bone formation is also
included in this invention.
Yet another object of the present invention to provide
pharmaceutical compositions comprising a therapeutically effective
amount of an EP.sub.4 receptor subtype agonist of formula I and a
bisphosphonate active.
It is another object of the present invention to provide methods
for treating or reducing the risk of contracting a disease state or
condition related to abnormal bone resorption in a mammal in need
of such treatment or prevention, comprising administering to said
mammal a therapeutically effective amount of an EP.sub.4 receptor
subtype agonist of formula I. Use of the compounds of formula I for
the manufacture of a medicament for treating or reducing the risk
of contracting a disease state or condition related to abnormal
bone resorption is also included in this invention.
The disease states or conditions related to abnormal bone
resorption include, but are not limited to, osteoporosis,
glucocorticoid induced osteoporosis, Paget's disease, abnormally
increased bone turnover, periodontal disease, tooth loss, bone
fractures, rheumatoid arthritis, periprosthetic osteolysis,
osteogenesis imperfecta, metastatic bone disease, hypercalcemia of
malignancy, and multiple myeloma.
Within the method comprising administering a therapeutically
effective amount of an EP.sub.4 receptor subtype agonist of formula
I and a bisphosphonate active, both concurrent and sequential
administration of the EP.sub.4 receptor subtype agonist of formula
I and the bisphosphonate active are deemed within the scope of the
present invention. Generally, the formulations are prepared
containing 5 or 10 mg of a bisphosphonate active, on a
bisphosphonic acid active basis. With sequential administration,
the agonist and the bisphosphonate can be administered in either
order. In a subclass of sequential administration the agonist and
bisphosphonate are typically administered within the same 24 hour
period. In yet a further subclass, the agonist and bisphosphonate
are typically administered within about 4 hours of each other.
A non-limiting class of bisphosphonate actives useful in the
instant invention are selected from the group consisting of
alendronate, cimadronate, clodronate, tiludronate, etidronate,
ibandronate, neridronate, olpandronate, risedronate, piridronate,
pamidronate, zolendronate, pharmaceutically acceptable salts
thereof, and mixtures thereof.
A non-limiting subclass of the above-mentioned class in the instant
case is selected from the group consisting of alendronate,
pharmaceutically acceptable salts thereof, and mixtures
thereof.
A non-limiting example of the subclass is alendronate monosodium
trihydrate.
In the present invention, as it relates to bone stimulation, the
agonist is typically administered for a sufficient period of time
until the desired therapeutic effect is achieved. The term "until
the desired therapeutic effect is achieved", as used herein, means
that the therapeutic agent or agents are continuously administered,
according to the dosing schedule chosen, up to the time that the
clinical or medical effect sought for the disease or condition
being mediated is observed by the clinician or researcher. For
methods of treatment of the present invention, the compounds are
continuously administered until the desired change in bone mass or
structure is observed. In such instances, achieving an increase in
bone mass or a replacement of abnormal bone structure with normal
bone structure are the desired objectives. For methods of reducing
the risk of a disease state or condition, the compounds are
continuously administered for as long as necessary to prevent the
undesired condition. In such instances, maintenance of bone mass
density is often the objective.
Nonlimiting examples of administration periods can range from about
2 weeks to the remaining lifespan of the mammal. For humans,
administration periods can range from about 2 weeks to the
remaining lifespan of the human, preferably from about 2 weeks to
about 20 years, more preferably from about 1 month to about 20
years, more preferably from about 6 months to about 10 years, and
most preferably from about 1 year to about 10 years.
The instant compounds are also useful in combination with known
agents useful for treating or preventing bone loss, bone fractures,
osteoporosis, glucocorticoid induced osteoporosis, Paget's disease,
abnormally increased bone turnover, periodontal disease, tooth
loss, osteoarthritis, rheumatoid arthritis, periprosthetic
osteolysis, osteogenesis imperfecta, metastatic bone disease,
hypercalcemia of malignancy, and multiple myeloma. Combinations of
the presently disclosed compounds with other agents useful in
treating or preventing osteoporosis or other bone disorders are
within the scope of the invention. A person of ordinary skill in
the art would be able to discern which combinations of agents would
be useful based on the particular characteristics of the drugs and
the disease involved. Such agents include the following: an organic
bisphosphonate; a cathepsin K inhibitor; an estrogen or an estrogen
receptor modulator; an androgen receptor modulator; an inhibitor of
osteoclast proton ATPase; an inhibitor of HMG-CoA reductase; an
integrin receptor antagonist; an osteoblast anabolic agent, such as
PTH; calcitonin; Vitamin D or a synthetic Vitamin D analogue; and
the pharmaceutically acceptable salts and mixtures thereof. A
preferred combination is a compound of the present invention and an
organic bisphosphonate. Another preferred combination is a compound
of the present invention and an estrogen receptor modulator.
Another preferred combination is a compound of the present
invention and an estrogen. Another preferred combination is a
compound of the present invention and an androgen receptor
modulator. Another preferred combination is a compound of the
present invention and an osteoblast anabolic agent.
Regarding treatment of abnormal bone resorption and ocular
disorders, the formula I agonists generally have an EC.sub.50 value
from about 0.001 nM to about 100 microM, although agonists with
activities outside this range can be useful depending upon the
dosage and route of administration. In a subclass of the present
invention, the agonists have an EC.sub.50 value of from about 0.01
microM to about 10 microM. In a further subclass of the present
invention, the agonists have an EC.sub.50 value of from about 0.1
microM to about 10 microM. EC.sub.50 is a common measure of agonist
activity well known to those of ordinary skill in the art and is
defined as the concentration or dose of an agonist that is needed
to produce half, i.e. 50%, of the maximal effect. See also, Goodman
and Gilman's, The Pharmacologic Basis of Therapeutics, 9th edition,
1996, chapter 2, E. M. Ross, Pharmacodynamics, Mechanisms of Drug
Action and the Relationship Between Drug Concentration and Effect,
and PCT US99/23757, filed Oct. 12, 1999, which are incoroporated by
reference herein in their entirety.
The herein examples illustrate but do not limit the claimed
invention. Each of the claimed compounds are EP.sub.4 agonists and
are useful for a number of physiological ocular and bone
disorders.
The compounds of this invention can be made, with some
modification, in accordance with U.S. Pat. No. 6,043,275,
EP0855389, WO 03/047417 (U.S. Ser. No. 60/337,228), WO 03/047513
(U.S. Ser. No. 60/338,117), U.S. Ser. No. 60/406,530 and WO
01/46140, all of which are incorporated herein by reference in
their entirety. The following non-limiting schemes and examples
given by way of illustration is demonstrative of the present
invention.
##STR00003##
PREPARATIVE EXAMPLE 1
##STR00004##
To a slurry of (+/-)-pipecolinic acid (395 g, 3.06 moles) in MeOH
(1.8 L) at 60.degree. C. was added L-tartaric acid (459 g, 3.06
moles). The slurry was warmed to reflux and aged 1 h (hour). The
slurry was cooled to 23.degree. C., filtered, and the desired
(R)-pipecolinic acid/L-tartaric acid filtercake was washed with
MeOH (200 mL). The filtercake was air dried a white solid was
isolated. The pipecolinic acid tartrate salt typically assayed at
85-89% ee.
A slurry of salt (383 g) in 2:1H.sub.2O/acetone (380 mL/190 mL) was
warmed to reflux (60-65.degree. C.) until all solids had dissolved.
Acetone (1330 mL) was added over 2 h while maintaining a reflux.
The slurry was allowed to cool to 15-20.degree. C. over 1 h and
then filtered, washed with 4:1 acetone/H.sub.2O (380 mL) and then
air dried under vacuum. Isolated 313 g of pipecolinic acid tartrate
salt (>99% ee).
To a slurry of (R)-pipecolinic acid tartrate salt (312 g) in MeOH
(3.0 L) was added 28% NH.sub.4OH (83 mL, 1.1 eq) over 0.5 h. The
white slurry was aged 0.5 h at ambient temperature and then the
ammonium tartrate precipitate was filtered off. The filtercake was
rinsed with MeOH (300 mL). The combined filtrate and rinse was
concentrated to a white solid of (1).
PREPARATIVE EXAMPLE 2
##STR00005##
To a slurry of pipecolinic acid (109.7 g) and BOC.sub.2O (222.4 g)
in 1:1 tetrahydrofuran (THF)/H.sub.2O (550/550 mL) was added 50%
NaOH (45 mL). The slurry was warmed to reflux and aged 5 h at
reflux. The solution was cooled to 23.degree. C. and then washed
with heptane (550 mL) to remove unreacted BOC.sub.2O. The aqueous
(aq.) layer was then acidified with 5N HCl (170 mL) to pH 4-5. The
resulting slurry was extracted with 550 mL of tert-butyl methyl
ether (MTBE). The organic layer was dried over Na.sub.2SO.sub.4 and
then concentrated to a white solid of (2).
PREPARATIVE EXAMPLE 3
##STR00006##
To a solution of N-BOC-pipecolinic acid (166.5 g, 726 mmoles) in
500 mL dimethylformamide (DMF) was added MeI (123.7 g, 871 mmoles)
and K.sub.2CO.sub.3 (100.4 g, 726 moles). The reaction mixture
slowly exothermed to 40.degree. C. after 0.5 h during a 4 h age
period at ambient temperature. Added MTBE (830 mL) and then washed
with H.sub.2O (2.times.830 mL) and 20% brine (300 mL). The organic
layer was dried over Na.sub.2SO.sub.4 and concentrated to an oil
(3).
PREPARATIVE EXAMPLE 4
##STR00007##
To a solution of butoxycarbonyl (Boc)-Me ester (152.6 g, 627 mmol)
in MeCN (305 mL) was added RuCl.sub.3 (2.6 g, 12.5 mmol). A
solution of NaBrO.sub.3 (142.0 g, 941 mmol) in H.sub.2O (760 mL)
was added over 2 h. The solution was aged 12 h at ambient
temperature. Added EtOAc (760 mL) and cut the aqueous layer. The
dark organic layer was washed with 10% Na.sub.2SO.sub.3 (305 mL)
while the organic layer turned clear and the aqueous layer turned
cloudy grey. The organic layer was washed with saturated brine (150
mL) and then dried over Na.sub.2SO.sub.4 to give oil (4).
PREPARATIVE EXAMPLE 5
##STR00008##
To a solution of BOC-Lactam (135.4 g, 526 mmol) in 135 mL of
isopropyl alcohol (IPA) was added 5N HCl in 263 mL/1316 mmol
isopropyl alcohol (IPA) over 15 min. Vigorous gas evolution
occurred for 15 min and then the solution was aged 2.5 h at ambient
temperature. Added EtOAc (800 mL) and washed with 15%
Na.sub.2CO.sub.3 (350 mL). The aqueous layer was extracted with
EtOAc (400 mL). The combined organic layers were dried over
Na.sub.2SO.sub.4 and concentrated to oil (5). The enantiomeric
purity was assayed at >99% ee.
PREPARATIVE EXAMPLE 6
##STR00009##
To a solution of lactam ester (8.10 g, 51.7 mmol) in anhydrous
ethanol (500 mL) was added sodium borohydride (2.5 g, 1.2 eq) in
0.5 g increments over 30 minutes. The solution was stirred for 3.5
hours at room temperature. The mixture was then treated with
glacial acetic acid (2.8 equiv) and the precipitate removed by
filtering through a plug of celite. The filtrate was then
concentrated in vacuo and the resulting oil solidified upon
standing under vacuum. The crude product was dissolved in
CH.sub.2Cl.sub.2 (50 mL), treated with KHCO.sub.3 (1.5 equiv), aged
for 1 h, filtered through a plug of Celite and the resulting
filtrate was concentrated in vacuo to give the title compound 6,
which was used directly in the next step without further
purification.
PREPARATIVE EXAMPLE 7
##STR00010##
To a solution of the lactam alcohol (10 g, 77.5 mmol, 1.0 equiv) in
anhydrous CH.sub.2Cl.sub.2 (50 mL) at 0.degree. C. under N.sub.2
atmosphere was added imidazole (6.9 g, 100.8 mmol, 1.3 equiv, (the
amount of imidazole was adjusted to neutralize any AcOH from the
previous step) and 14 g/93.0 mmol/1.2 equiv of
tert-butyldimethylsilyl chloride (TBSCl). The resulting mixture was
warmed to room temperature (RT) and aged for 4 hours. Once the
reaction was judged complete, CH.sub.2Cl.sub.2 (100 mL) was added,
followed by 1N HCl solution (30 mL). The organic layer was
separated and the aqueous layer was back-extracted with
CH.sub.2Cl.sub.2 (2.times.50 mL). The combined organic layer was
washed with 20% NaHCO.sub.3 solution (40 mL), brine, dried over
MgSO.sub.4, filtered and concentrated in vacuo to give the desired
compound as white solid. The silicon-containing byproducts can be
removed by washing the solid with cold heptane (3 mL/g) at
-78.degree. C. to give the titled compound 7.
PREPARATIVE EXAMPLE 8
##STR00011##
To a 15.degree. C. solution of lactam 7 (2.0 g, 8.22 mmoles) in THF
(KF<200 ppm) was added 1.90 g/9.04 mmoles of solid potassium
bis[trimethylsilyl]amide (KHMDS) in 20 mL of tetrahydrofuran (THF)
and aged for 10 min at room temperature (rt). Freshly prepared
mesylate (0.93 g, 8.22 mmoles, KF<800 ppm) was added to the
solution as a neat oil and the reaction was heated to 50.degree. C.
and aged for 2.5-3.5 h. The reaction was cooled to rt and diluted
with MTBE (20 mL) and water (20 mL). The aqueous (aq.) layer was
cut and the organics were washed with sat'd. brine (10 mL). Upon
drying over Na.sub.2SO.sub.4, the solvent was removed to yield
crude yellow oil 8.
PREPARATIVE EXAMPLE 9
##STR00012##
To a solution of the tert-butyldimethylsilyl (TBS)-protected lactam
(10 g, 24.2 mmol, 1 equiv) in dry MTBE (40 mL) at 0.degree. C.
under N.sub.2 atmosphere was added a 70% solution of
HF.cndot.Pyridine (4.84 g, 169 mmol, 7 equiv) over 15 min. The
resulting mixture was allowed to warm to RT and aged for 12 h, at
which the reaction was judged complete by HPLC and .sup.1HNMR
analysis. The mixture was then diluted with MTBE (100 mL) and
washed with cold H.sub.2O (30 mL). The organic layer was then
treated with saturated Na.sub.2CO.sub.3 (25 mL), brine, dried over
MgSO.sub.4, filtered and concentrated in vacuo. The resulting crude
oil (9) is used directly in the next step. If desired, the alcohol
can be purified by SiO.sub.2 gel flash column chromatography (40:1
CH.sub.2Cl.sub.2:MeOH).
PREPARATIVE EXAMPLE 10
##STR00013##
To a cold solution (0.degree. C.) of alcohol 9 (9.46 g, 31.6 mmol),
DMSO (237.3 mmol, 16.9 mL, 7.5 equiv), and Hunig base (16.5 mL,
94.9 mmol, 3 equiv) in dichloromethane (95 mL) was added
SO.sub.3.cndot.Pyridine (15 g, 94.9 mmol, 3 equiv) as a solid over
15 minutes. The resulting solution was aged at 0.degree. C. for 1.5
h, at which complete consumption of the starting material was
observed. The reaction mixture was then diluted with EtOAc (150 mL)
and washed with cold 4N aqueous HCl (35 mL). The organic layer was
separated and treated successively with saturated NaHCO.sub.3
solution and brine. The solution then dried over MgSO.sub.4
filtered and concentrated in vacuo to give the corresponding
aldehyde (7.8 g, 83% assay yield), which was used in the next step
without further purification.
PREPARATIVE EXAMPLE 11
Preparation of Sodium Phosphonate 14
Step 1
##STR00014##
To a neat solution of methyl benzoylformate (PhCOCO.sub.2Me, 25 g,
0.15 mol, 1 equiv) at 15.degree. C. under N.sub.2 atmosphere was
added neat diethylaminosulfur trifluoride (DAST, 34.4 g, 0.21 mol,
1.4 equiv) at a rate such that the internal temperature was
maintained below 45.degree. C. At the end of the addition, the
resulting brown solution was allowed to cool to RT and aged for 3
more hours, at which time a complete consumption of starting
material was observed by high performance liquid chromatography
(HPLC) and gas chromatography/mass spectroscopy (GC/MS). The
reaction mixture was then poured slowly into a mixture of
ice/H.sub.2O (NOTE: exothermic!) and the product was extracted with
MTBE (3.times.). The combined organic layer was then neutralized
slowly to a pH of 7 with a cold solution of 20% aqueous
Na.sub.2CO.sub.3 (NOTE: gas evolution), washed with brine, dried
over MgSO.sub.4, filtered and concentrated in vacuo. The crude
product was purified by vacuum distillation (bp=103-105.degree. C.
at 24-25 torr) to give the desired product (13) as slightly yellow
oil.
Step 2
##STR00015##
To a solution of dimethyl methylphosphonate (28 g, 0.23 mol, 1.05
equiv) in dry THF (400 mL, KF=30 ppm) under N.sub.2 atm at
-78.degree. C. was slowly added a 2M solution of sodium
bis(trimethylsilyl)amide in THF (115 mL, 0.23 mol, 1.05 equiv) over
15 min. The resulting solution was aged for 30 min and then treated
with neat methyl difluoroester (PhCF.sub.2CO.sub.2Me, 40 g, 0.22
mol, 1.0 equiv) over 15 min. The reaction mixture was aged at
-78.degree. C. for 1 h, slowly warmed to RT and concentrated to
about a quarter of its original volume and added MTBE (400 mL) over
0.5 h. The resulting suspension was further aged at RT for 0.5 h
and filtered. The wet cake was washed with MTBE (100 mL) and dried
in vacuo under a stream of N.sub.2. The product was isolated as
white solid (14).
PREPARATIVE EXAMPLE 12
Preparation of Compound 16
Step 1
##STR00016##
To a 10.degree. C. solution of water (250 mL), IPA (1250 mL) and
concentrated sulfuric acid (600 mL, 11.1 moles) was added solid
potassium persulfate (600 g, 2.22 moles) in one portion.
Cycloheptanone (131.5 mL) was diluted to 250 mL total volume with
EPA and this solution was added via addition funnel to the
persulfate slurry over 15 min with the temperature maintained
<15.degree. C. throughout the addition. The reaction was aged at
15.degree. C. for 16-20 h. Once all of the cycloheptanone had
reacted, the reaction was filtered to remove the salts, keeping the
filtrate cold. The filtrate was diluted with MTBE (1250 mL), sat'd
brine (1 L), and water (500 mL), with the temperature maintained
<30.degree. C. Upon transfer to a separatory funnel, the phases
were allowed 1 h to settle and the aqueous layer was cut. The
organic layer was washed with sat'd. Na.sub.2CO.sub.3 (2.times.1
L), or until the aq. cut remained basic. The solution was diluted
with hexanes (1.25 L) and dried over Na.sub.2SO.sub.4 for 1 h. The
solvent was removed under vacuum and the oil was vacuum distilled
to yield pure ester (16). (bp 125.degree. @ 4 mm Hg)
Step 2
##STR00017##
To a -10.degree. C. solution of ester (10 g, 0.05 moles) and
triethylamine (11.1 mL, 0.08 moles) in dry THF (100 mL) was added
Methanesulfonyl chloride (MsCl-4.75 mL, 0.06 moles) (diluted 1:1 in
THF) with the temperature maintained <10.degree. C. throughout
the addition. The reaction was aged for 30 min @ 0-5.degree. C.
Upon completion, the reaction was diluted with hexanes (100 mL) and
quenched with water (50 mL). The aq. layer was cut and the organic
layer was dried over Na.sub.2SO.sub.4 for 30 min. The solvent was
removed under vacuum and gave a yellow oil (16). The mesylate
should be prepared fresh prior to lactam alkylation in order to
minimize impurities.
EXAMPLE 1
isopropyl7-{(2R)-2-[(1E)-4,4-difluoro-3-oxo-4-phenylbut-1-en-1-yl]-6-oxopi-
peridin-1-yl}heptanoate
##STR00018##
To a solution of sodium phosphonate 14 (13.7 g, 45.7 mmol, 1.4
equiv) in THF (130 mL) at 0.degree. C. under nitrogen was added
ZnCl.sub.2 (3.33 g, 24.5 mmol, 0.75 equiv). The resulting mixture
was stirred at rt for 15 minutes and then treated with a solution
of aldehyde 10 (9.7 g, 32.66 mmol, 1 equiv) in THF (10 mL). The
resulting suspension was then heated to 50.degree. C. for 50 h, at
which a 94-97% conversion was observed. The mixture was then
concentrated to about a third of its volume, diluted with EtOAc
(130 mL), washed with H.sub.2O (30 mL) and brine. The organic layer
was then dried over MgSO.sub.4, filtered and concentrated to give
yellow oil (11), which can be purified by SiO.sub.2 gel flash
chromatography (19:1.fwdarw.9:1 toluene:acetone).
EXAMPLE 2
7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-1-yl]-6-oxopipe-
ridin-1-yl}heptanoate (12)
##STR00019##
To a solution of the enone (450 mg, 1 mmol, 1.0 equiv) in 0.5
M/.about.4.5 mL/g anhydrous PhCH.sub.3 or dichloromethane (DCM)
under N.sub.2 atmosphere was added Et.sub.3N (0.14 mL, 1 mmol, 1.0
equiv) and HCO.sub.2H (0.05 mL, 1.2 mmol, 1.2 equiv) at room
temperature (RT). The resulting solution was stirred for 10 min and
then treated with solid (R,R)-(-)-RuTsDPEN-cymene complex.sup.1 (19
mg, 0.03 mmol, 0.03 equiv) all at once. The reaction mixture was
then aged at RT for 2 h, at which a complete consumption of
starting material was observed. Tert-butyl methyl ether-MTBE (5 mL)
was added followed by 1N HCl (2 mL). The organic layer was
separated, washed with saturated Na.sub.2CO.sub.3, brine, dried
over MgSO.sub.4, filtered and concentrated in vacuo to give the
final compound as viscous oil.
The catalyst can also be generated in situ by mixing 0.02 mol equiv
of [RuCl.sub.2(p-cymene).sub.2] and 0.04 mol equiv of the
(R,R)-N-Tosyl-1,2-diphenylethylene-1,2-diamine in DCM
(dichloromethane) in the presence of 0.04 mol equiv of 1M solution
KOtBu in THF (tetrahydrofuran). After aging for 10 min at RT,
Et.sub.3N was added followed by HCO.sub.2H and a solution of the
enone in DCM).
The catalyst was prepared by mixing 1 mol equiv of
[RuCl.sub.2(p-cymene).sub.2], 2 mol equiv
(R,R)-N-Tosyl-1,2-diphenylethylene-1,2-diamine and 4.2 mol equiv of
Et.sub.3N in iPrOH at 80.degree. C. for 1 h (hour). After solvent
removal, the solid was washed with cold H.sub.2O and the
recrystallized from MeOH to give the catalyst as orange solid.
EXAMPLE 3
7-{(2R)-2-[(1E,
3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-1-yl]-6-oxopiperidin-1-yl}hep-
tanoic acid
##STR00020## Step 1: isopropyl
7-[(2R)-2-({[tert-butyl(dimethyl)silyl]oxy}methyl)-6-oxopiperidin-1-yl]he-
ptanoate
##STR00021##
To a solution of 7 (1.0 g, 4.1 mmol, synthesized in seven steps
according to the literature procedure Synthesis 1998, 1141-1144.)
in 12 mL DMF (dimethyl formamide) was added 60% sodium hydride (172
mg, 4.3 mmol) and the resulting solution was stirred for 30 min at
50.degree. C. whereupon isopropyl-7-iodoheptanoate, 17, (1.9 g, 1.6
mL, 8.2 mmol) and tetrabutylammonium iodide (50 mg) were added. The
solution was stirred at 50.degree. C. overnight after which it was
cooled to room temperature, slowly poured into saturated aqueous
ammonium chloride solution and was extracted with ether. The
organic phases were then combined and sequentially washed with
H.sub.2O, brine and dried over Na.sub.2SO.sub.4, filtered and
concentrated in vacuo. The compound was purified by flash
chromatography using 75-100% ethyl acetate/hexanes to yield 9 as a
colorless oil. 1H NMR (500 MHz, Acetone-d6): .delta. 4.95 (m, 1H),
3.75 (m, 3H), 3.50 (m, 1H), 2.97 (m, 1H), 2.25 (2t, 4H), 2.00 (m,
1H), 1.93 (m, 1H), 1.82 (m, 1H), 1.70-1.56 (m, 4H), 1.52 (m, 1H),
1.40-1.28 (m, 4H), 1.22 (2s, 6H), 0.93 (s, 9H), 0.11 (s, 6H).
Step 2: isopropyl
7-[(2R)-2-(hydroxymethyl)-6-oxopiperidin-1-yl]heptanoate
##STR00022##
To a solution of 8 (0.80 g, 2.3 mmol) in 10 mL was added
TBAF-tetrabutylammonium fluoride (0.25 mL of a 1M solution in THF)
at room temperature and stirred for 18 hours. The solution was then
quenched with saturated (sat'd.) NaHCO.sub.3, and extracted with
ethyl acetate. The organic layers were combined and washed with
water then brine, dried over MgSO.sub.4, filtered and concentrated
in vacuo to yield 9 as a colorless oil. .sup.1H NMR (500 MHz,
Acetone-d6): .delta. 4.95 (m, 6H), 3.97 (t, 1 H, OH), 3.76 (m, 1H),
3.66 (m, 2H), 3.48 (m, 1H), 2.98 (m, 1H) 2.24 (m, 4H), 2.08 (m,
1H), 1.90 (m, 1H), 1.79 (m, 1H), 1.70-1.56 (m, 4H), 1.50 (m, 1H),
1.40-127 (m, 4H), 1.22 (2s, 6H).
Step 3: isopropyl
7-{(2R)-2-[(1E)-4,4-difluoro-3-oxo-4-phenylbut-1-en-1-yl]16-oxopiperidin-
1-yl}heptanoate
##STR00023##
To a purged flask with N.sub.2 (g) was added CH.sub.2Cl.sub.2 (40
mL) to which dimethylsulfoxide (0.115 g, 0.10 mL, 1.48 mmol) was
then added. The solution was then cooled to -78.degree. C. and
during vigorous stirring oxalyl chloride (0.17 g, 0.12 mL, 1.3
mmol) was added dropwise. After 30 min a solution of 9 (0.35 g, 1.2
mmol) in 5 mL CH.sub.2Cl.sub.2 was added via cannula. Stirring was
continued for another 30 min at -78.degree. C. Triethyl amine (0.31
g, 0.43 mL, 3.1 mmol) was added dropwise and after 15 min of
stirring was concentrated in vacuo without the use of the bath. A
solution of 1:1 diethyl ether/ethyl acetate (100 mL) was used to
filter off the triethylamine salts and the solution was
concentrated in vacuo. The crude aldehyde, 10, was then diluted in
5 mL of THF and added to a solution of
(2-oxo-3-phenyl-propyl)-phosphonic acid dimethyl ester (0.34 g, 1.4
mmol) and 60% sodium hydride (52 mg, 1.3 mmol) in 15 mL of THF at
0.degree. C. which had been premixed 1 hour. Zinc chloride (x mL of
a 1M solution in THF was added) and the reaction mixture was
stirred overnight at 50.degree. C. The solution was quenched with
saturated aqueous ammonium chloride solution and was extracted with
ethyl acetate. The organic phases were then combined, and
sequentially washed with H.sub.2O, brine and dried over
Na.sub.2SO.sub.4, filtered and concentrated in vacuo. The compound
was purified by flash chromatography using 50-80% ethyl
acetate/hexanes to yield 11 as a colorless oil. 1H NMR (400 MHz,
Acetone-d6): .delta. 7.65-7.55 (m, 5H), 7.11 (dd, 1H), 6.67 (d,
1H), 4.95 (m, 1H), 4.40 (m, 1H), 3.78 (m, 1H), 2.60 (m, 1H), 2.25
(m, 4H), 2.02 (m, 1H), 1.90 (m, 1H), 1.68 (m, 2H), 1.53-1.36 (m,
4H), 1.35-1.17 (m, 10H).
Step 4: isopropyl
7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-1-yl]-6-oxopip-
eridin-1-yl}heptanoate
##STR00024##
A. Synthesis of butyl-(S)-CBS in toluene: To a solution of (S)-CBS
ligand (11.53 g, 45.5 mmol) in toluene (110 mL) was added
butylboronic acid (5.1 g, 47.8 mmol) and the mixture was heated to
reflux over night with a Dean stark. This final solution was 0.48 M
and was used directly.
B. Reduction: To a solution of catecholborane (3.35 mL, 31.4 mmol)
in toluene (400 mL) cooled to -78.degree. C. was added 68 mL (32.6
mmol) of (S)-2-butyl-CBS oxazaborolidine solution under nitrogen
and the mixture was stirred at the temperature for 1 hour (h).
Ketone 11 (7 g, 15.6 mmol) in toluene (420 mL) was added dropwise
in 1 h under nitrogen and the mixture stirred at the temperature
until all starting material disappeared (usually in 30 min). To the
mixture was then added 200 mL 1N HCl and the mixture allowed to
warm to room temperature with vigorous stirring. The mixture was
extracted with ethyl acetate (emulsion developed during extraction
and the suspension was filtered through celite to remove emulsion).
The crude product was purified by flash chromatograph. Eluting with
EA/hexanes (70-100%) gave the desired alcohol as a mixture of two
diastereomers in a ratio of 12:1. The mixture was easily separated
by prep HPLC (high performance liquid chromatograpy) using a chiral
Pak AD.RTM. column using 50% iPrOH in hexanes as eluants
(monitoring at .lamda. 214 nm). The undesired isomer came out first
followed by the desired isomer 12.
.sup.1H NMR (400 MHz, Acetone-d.sub.6): .delta. 7.6-7.5 (m, 2H),
7.5-7.4 (m, 3H), 5.80 (dd, 1H), 5.6 (dd, 1H), 5.0-4.9 (m, 2H),
4.7-4.6 (m, 1H), 4.1-4.0 (m, 1H), 3.8-3.7 (m, 1H), 2.6-2.5 (m,1H),
2.3-2.2 (m, 4H), 1.9-1.8 (m, 1H), 1.75-1.55 (m, 5H), 1.55-1.4 (m,
2H), 1.4-1.22 (m, 4H), 1.22 (d, 6H).
Step 5: 7-{(2R)-2-[(1E,
3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-1-yl]-6-oxopiperidin-1-yl}
heptanoic acid
##STR00025##
To a solution of 12 (39 mg, 0.089 mmol) in 2.75 mL 2.5:2.5:1
THF:MeOH:water, at 0.degree. C., was added lithium hydroxide (145
.mu.L of a 2M solution in water) and the resulting solution was
allowed to warm to room temperature and stirred overnight. To the
solution was added a 1M aqueous solution of HCl (1 mL) and the
solution was extracted with ethyl acetate. The organic phases were
then combined, washed with brine, dried over MgSO.sub.4, filtered
and concentrated in vacuo. The compound was purified by flash
chromatography using 49-45%/1-5%/1 drop
CH.sub.2Cl.sub.2/methanol/acetic acid to yield 18 as a colorless
oil. .sup.1H NMR (500 MHz, Acetone-d6): .delta. 7.6-7.5 (m, 5H),
5.8 (dd, 1 H), 5.6 (dd, 1H), 5.6 (bs, 1 H), 4.6 (m, 1H), 4.1 (m,
1H), 3.7 (m, 1H), 2.6 (m, 1H), 2.4-2.2 (m, 4H), 1.9-1.2 (m,
12H).
The following Examples 4 through 13 can be made in accordance with
Examples 1-3 with the appropriate modifications.
EXAMPLE 4
7-{(2R)-2-[(3R)-4-(3-bromophenyl)-4,4-difluoro-3-hydroxybutyl]-6-oxopiperi-
din-1-yl}heptanoic acid
MS (+ESI): m/z 490.1 (M+1).sup.+.
##STR00026##
EXAMPLE 5
7-{[(2R)-2-(3R)-3-hydroxy-4-phenyl-butyl]-6-oxopiperdin-1-yl}heptanoic
acid
.sup.1H NMR (400 MHz, CD.sub.3OD): .delta. 7.3-7.1 (m, 5H), 3.8-3.7
(m, 2H), 3.4 (m, 1H), 2.9-2.7(m, 3H), 2.3 (m, 4H), 1.9-1.3 (m,
16H); MS (-ESI): m/z 374.2 (M-1).sup.-.
##STR00027##
EXAMPLE 6
methyl 5-{3-[(2R)-2-((1E)-(3S)
3-hydroxy-4-phenyl-but-1-enyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2--
carboxylate
.sup.1H NMR (400 MHz, CDCl.sub.3): .delta. 7.6 (d, 1H), 7.2-7.1 (m,
5H), 6.7 (d, 1H), 5.5 (m, 2H), 4.3 (m, 1H), 3.8-3.7 (m, 2H), 3.8
(s, 3H), 2.8-2.6 (m, 6H), 2.3-2.2 (m, 2H), 1.9-1.2 (m, 6H).
##STR00028##
EXAMPLE 7
5-{3-[(2R)-2-((1E)-(3S)
3-hydroxy-4-phenyl-but-1-enyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2--
carboxylic acid
.sup.1H NMR (400 MHz, CD.sub.3OD): .delta. 7.6 (d, 1H), 7.2-7.1 (m,
5H), 6.9 (d, 1H), 5.5 (m, 2H), 4.3 (m, 1H), 3.9 (m, 1H), 3.7 (m,
1H), 2.9-2.6 (m, 5H), 2.2 (m, 2H), 1.9-1.5 (m, 6H); MS (-ESI): m/z
412.1 (M-1).sup.-.
##STR00029##
EXAMPLE 8
5-{3-[(2R)-2-((3S)
3-hydroxy-4-phenyl-butyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2-carbo-
xylic acid
.sup.1H NMR (400 MHz, CD.sub.3OD): .delta. 7.6 (d, 1H), 7.3-7.1 (m,
5H), 6.9 (d, 1H), 1H), 3.0-2.9 (m, 1H), 2.8-2.5 (m, 4H), 2.3 (m,
2H), 2.0-1.3 (m, 10H); MS (-ESI): m/z 414.1 (M-1).sup.-.
##STR00030##
EXAMPLE 9
isopropyl 5-{3-[(2R)-2-((1E)-(3S)
3-hydroxy-4-phenyl-but-1-enyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2--
carboxylate
.sup.1H NMR (400 MHz, CDCl.sub.3): .delta. 7.6 (d, 1H), 7.3-7.1 (m,
5H), 6.8 (d, 1H), 5.5 (m, 2H), 5.1 (m, 1H), 4.4 (m, 1H), 3.9-3.8
(m, 2H), 3.3 (br s, 1H), 2.8 (m, 4H), 2.7 (m, 1H), 2.3 (m, 2H),
1.9-1.6 (m, 6H), 1.3 (dd, 6H); MS (+ESI): m/z 456.4
(M+1).sup.+.
##STR00031##
EXAMPLE 10
isopropyl 5-{3-[(2R)-2-((3S)
3-hydroxy-4-phenyl-butyl)-6-oxo-piperidin-1-yl]-propyl}-thiophene-2-carbo-
xylate
.sup.1H NMR (400 MHz, CDCl.sub.3): .delta. 7.6 (d, 1H), 7.3-7.1 (m,
5H), 6.8 (d, 1H), 5.2 (m, 1H), 3.9-3.8 (m, 2H), 3.3 (m, 1H),
2.9-2.8 (m, 4H), 2.7-2.6 (m, 1H), 2.4-2.3 (m, 3H), 2.0-1.2 (m,
10H), 1.3 (d, 6H); MS (+ESI): m/z 458.2 (M+1).sup.+.
##STR00032##
EXAMPLE 11
6-[(3R)-3-hydroxy-4-phenyl-butyl]-1-[6-(1H-teraazol-5-yl)-hexyl]-piperidin-
-2-one
.sup.1H NMR (400 MHz, CD.sub.3OD): .delta. 7.3-7.1 (m, 5H), 3.8-3.7
(m, 2H), 3.3 (m, 1 H), 2.9-2.7 (m, 5H), 2.3 (m, 2H), 1.9-1.3 (m,
16H); MS (+ESI): m/z 400.3 (M+1).sup.+.
##STR00033##
EXAMPLE 12
isopropyl
(5Z)-7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en--
1-yl]-6-oxopiperidin-1-yl}hept-5-enoate
MS (+ESI): m/z 450.3 (M+1).sup.+.
##STR00034##
EXAMPLE 13
(5Z)-7-{(2R)-2-[(1E,3R)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-1-yl]-6-ox-
opiperidin-1-yl}hept-5-enoic acid
MS (-ESI): m/z 406.1 (M-1).sup.-.
##STR00035##
EXAMPLE 14
isopropyl-7-{(4R)-4-[(1E)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-yl]-2-ox-
o-1,3-oxanzinan-3-yl}heptanoate
MS (+ESI): m/z 454 (M+1).sup.+.
##STR00036## Step 1 Preparation of
(4S)-4-[2-(4-methoxyphenoxy)ethyl]-2,2-dimethyl-1,3-dioxolane
To a solution of 2-[(4S)-2,2-dimethyl-1,3-dioxolan-4-yl]ethanol
(Aldrich, 5 g, 34.2 mmol) in THF was added sodium hydride 60%
(1.504 g, 37.6 mmol, 1.1 eq) portionwise and the mixture stirred
for 1 h (cloudy solution). The mixture was cooled to 0.degree. C.
and to it was added 4-methoxybenzyl chloride (5.89 g, 37.6 mmol,
1.1 equivalent (eq.)) in one portion and the mixture stirred at the
temperature for 30 min and heated to 65-70.degree. C. overnight.
After cooling to rt and quenching with saturated NH.sub.4Cl/water,
the mixture was extracted with ethyl acetate (2.times.) and the
organic extracts were washed with water, brine and dried over
MgSO.sub.4. The mixture was filtered and the filtrate was
concentrated in vacuo. The crude product was purified by silica gel
chromatography (15% ethyl acetate/hexanes) to give desired product
as a colorless oil. .sup.1H NMR (400 MHz, Acetone-d.sub.6):
.delta.7.28 (2 H, d), 6.93-6.91 (2 H, m), 4.43 (2 H, s), 4.20-4.14
(1 H, m), 4.04-3.98 (1 H, m), 3.80 (3H, s), 3.56-3.50 (3H, m),
1.88-1.76 (2H, m), 1.31 (3H, s), 1.28 (3 H, s).
Step 2
Preparation of (2S)-4-(4-methoxyphenoxy)butane-1,2-diol
A solution of
(4S)-4-[2-(4-methoxyphenoxy)ethyl]-2,2-dimethyl-1,3-dioxolane (8.2
g, 30.8 mmol) in AcOH/water was stirred at rt for 5 h and
concentrated in vacuo. The residue was co-evaporated with toluene
(3.times.) and then pumped under high vacuum to give the desired
product. .sup.1H NMR (400 MHz, Acetone-d.sub.6): .delta.7.28 (2 H,
d), 6.91 (2 H, d), 4.43 (2 H, s), 3.80 (3 H, s), 3.77 (1H, m),
3.66-3.42 (5 H, m), 1.86-1.76 (1H, m), 1.68-1.60 (1H, m).
Step 3
Preparation of
(1S)-1-({[tert-butyl(dimethyl)silyl]oxy}methyl)-3-(4-methoxyphenoxy)propy-
l methanesulfonate
To a solution of (2S)-4-(4-methoxyphenoxy)butane-1,2-diol (7 g,
30.9 mmol) and imidazole (4.21 g) in DMF (50 mL) was added
t-Butyldimethylsilyl chloride (4.88 g, 32.4 mmol, 1.05 eq) in one
portion at 0.degree. C. and the mixture was stirred at the
temperature for 1 h and diluted with water/ether. The layers were
separated and the aqueous layer extracted with ether (2.times.).
The extracts were combined, wased with water, brine, dried and
filtered. The filtrated was concentrated in vacuo to give 10.8 g
crude product
(2S)-1-{[tert-butyl(dimethyl)silyl]oxy}-4-(4-methoxyphenoxy)butan-2-ol
as a colorless oil. The crude NMR indicated that the product was
over 95% pure and thus it was used directly without purification.
.sup.1H NMR (400 MHz, Acetone-d.sub.6): .delta.7.28 (2 H, d),
6.92-6.90 (2 H, m), 4.43 (2 H, s), 3.80 (3 H, s), 3.75 (1H, m),
3.67-3.51 (5 H, m), 1.89-1.81 (1H, 1.66-1.58 (1 H, m), 0.91 (s,
9H), 0.09 (s, 6 H).
To a solution of
(2S)-1-{[tert-butyl(dimethyl)silyl]oxy}-4-(4-methoxyphenoxy)butan-2-ol
(10.5 g, 30.8 mmol) in dichloromethane (DCM) (50 mL) at 0.degree.
C. was added triethylamine (6.5 mL) followed by MsCl (2.9 mL)
dropwise and the mixture (light yellow suspension) was stirred for
1 h and quenched with water. The layers were separated and the
organic layer dried over MgSO.sub.4. The mixture was filtered and
the filtrate was concentrated in vacuo to give the desired
methanesulfonate. .sup.1H NMR (400 MHz, Acetone-d.sub.6):
.delta.7.29 (2 H, d), 6.91 (2 H, d), 4.84-4.78 (1 H, m), 4.49-4.41
(2 H, m), 3.90 (1 H, dd), 3.84 (1H, dd), 3.80 (3H, s), 3.62-3.54
(2H, m), 3.09 (3 H, s), 2.04-1.90 (2 H, m), 0.91 (s, 9H), 0.12-0.06
(6 H, m).
Step 4
Preparation of
{[(2R)-2-azido-4-(4-methoxyphenoxy)butyl]oxy}(tert-butyl)dimethylsilane
A mixture of
(1S)-1-({[tert-butyl(dimethyl)silyl]oxy}methyl)-3-(4-methoxyphenoxy)propy-
l methanesulfonate (13 g) and NaN.sub.3 (10 g) in DMF (50 mL) was
heated to 60-70.degree. C. under N.sub.2 o/n and cooled to rt. The
mixture was diluted with ether/water and extracted with ether
(3.times.). The ether extracts were washed with water, brine and
then worked up as usual. The crude was purified by flash
chromatography (5% ethyl acetate/hexanes) to give the desired azido
product. .sup.1H NMR (400 MHz, Acetone-d.sub.6): .delta.7.29 (2 H,
d), 6.92 (2 H, d), 4.45 (2 H, s), 3.87 (1 H, dd), 3.80 (3 H, s),
3.70-3.54 (4 H, m), 1.85-1.77 (1 H, m), 1.68-1.60 (1 H, m), 0.93 (9
H, s), 0.11 (6 H, s).
Step 5
Preparation of
(3R)-3-amino-4-{[tert-butyl(dimethyl)silyl]oxy}butan-1-ol
To a solution of
{[(2R)-2-azido-4-(4-methoxyphenoxy)butyl]oxy}(tert-butyl)dimethylsilane
(4.7 g, 12.86 mmol) in 19:1 DCM/water at 0.degree. C. was added DDQ
(2,3-Dichloro-5,6-dicyano-1,4-benzoquinone) (3.5 g, 15.43 mmol, 1.2
eq) and the mixture was stirred (from 0.degree. C. to rt) until all
starting material disappeared as indicated by TLC (thin layer
chromatography) analysis. Most DCM was then removed in vacuo and
the residue was dissolved in ethyl acetate. The ethyl acetate
solution was washed with water and saturated NaHCO.sub.3 repeatedly
until a pale yellow organic solution was obtained. The organic
solution was dried and the crude was purified by silica gel
chromatography (5% acetone/toluene) to give the desired product
(3R)-3-azido-4-{[tert-butyl(dimethyl)silyl]oxy}butan-1-ol. .sup.1H
NMR (400 MHz, Acetone-d.sub.6): .delta.3.89 (1 H, dd), 3.73-3.65 (5
H, m), 1.76-1.68 (1 H, m), 1.62-1.54 (1 H, m), 0.94 (9 H, s), 0.13
(6 H, s).
A mixture of
(3R)-3-azido-4-{[tert-butyl(dimethyl)silyl]oxy}butan-1-ol (2.94 g)
and Lindlar's catalyst (5% Pd/CaCO.sub.3, 1.27 g) in ethanol (50
mL) was hydrogenated under 51 psi H.sub.2 for 3.5 h and filtered.
The filtrate was concentrated to give 2.97 g crude product
(3R)-3-amino-4-{[tert-butyl(dimethyl)silyl]oxy}butan-1-ol with good
purity. .sup.1H NMR (CDCl.sub.3, 400 MHz): 3.85 (2 H, t), 3.54 (1H,
dd), 3.42 (1 H, dd), 3.03-2.97 (1 H, m), 2.44 (3 H, br s),
1.64-1.52 (2 H, m), 0.92 (9 H, s), 0.08 (6 H, s).
Step 6
Preparation of
(4R)-4-({[tert-butyl(dimethyl)silyl]oxy}methyl)-1,3-oxazinan-2-one
To a solution of
(3R)-3-amino-4-{[tert-butyl(dimethyl)silyl]oxy}butan-1-ol (2.63 g,
12 mmol) in DCM (100 mL) at 0.degree. C. was added pyridine (3 mL)
followed by phosgene (20% solution in toluene, 1.9 M, 8.5 mL)
dropwise and the mixture was stirred for 30 min and allowed to warm
to rt, and quenched with water. The layers were separated and the
water layer extracted with DCM once. The organic layers were dried
over MgSO.sub.4, filtered and concentrated. The desired product
(4R)-4-({[tert-butyl(dimethyl)silyl]oxy}methyl)-1,3-oxazinan-2-one
was obtained from crystallization from ether/hexanes at -20.degree.
C. as a light yellow solid. .sup.1H NMR (400 MHz, CDCl.sub.3) 5.52
(br s, 1H), 4.38-4.33 (m, 1H), 4.28-4.22 (m, 1H), 3.70-3.59 (m,
2H), 3.46 (t, 1H), 1.97-1.93 (m, 1H), 1.72-1.67 (m, 1H), 0.91 (s,
9H), 0.90 (s, 6H).
Step 7
Preparation of isopropyl
7-[(4R)-4-(hydroxymethyl)-2-oxo-1,3-oxazinan-3-yl]heptanoate
To a solution of
(4R)-4-({[tert-butyl(dimethyl)silyl]oxy}methyl)-1,3-oxazinan-2-one
(0.51 g, 2.078 mmol) in DMF (10 mL) at rt under N.sub.2 was added
KHMDS (0.5 M in toluene, 5 mL) dropwise (gel like precipitation
formation) and the mixture was stirred for 10 min. Isopropyl
7-iodoheptanoate (1.24 g, 4.16 mmol, 2 eq) was then added in one
portion and the mixture stirred at 65.degree. C. for an additional
5 h and cooled to rt, diluted with water/ether. The layers were
separated and the aqueous layer extracted with ether. The organic
layers were combined, washed with water and brine, dried over
MgSO.sub.4 and filtered. The filtrate was concentrated in vacuo and
the residue purified by column chromatography (15-30%
acetone/toluene) to give desired product isopropyl
7-[(4R)-4-({[tert-butyl(dimethyl)silyl]oxy}methyl)-2-oxo-1,3-oxazinan-3-y-
l]heptanoate as a colorless oil. .sup.1H NMR (400 MHz,
Acetone-d.sub.6): .delta.4.98-4.90 (1 H, m), 4.38-4.30 (1 H, m),
4.16-4.12 (1 H, m), 3.83-3.77 (2 H, m), 3.56-3.48 (2 H, m),
3.15-3.07 (1 H, m), 2.26 (2 H, t), 2.11-2.09 (2 H, m), 1.69-1.53 (4
H, m), 1.41-1.27 (4 H, m), 1.21 (6 H, d), 0.92 (9 H, s), 0.12 (6 H,
s).
To the product thus obtained (0.6 g, 1.444 mmol) in THF (5 mL) was
added AcOH (0.06 mL) and TBAF (1M in THF, 2.9 mL), and the mixture
was stirred at rt for 30 min and then concentrated. The crude was
purified by flash chromatography (30-50% acetone/toluene) to give
desired product isopropyl
7-[(4R)-4-(hydroxymethyl)-2-oxo-1,3-oxazinan-3-yl]heptanoate.
.sup.1H NMR (400 MHz, Acetone-d.sub.6): .delta.5.00-4.90 (1 H, m),
4.37-4.31 (1 H, m), 4.16-4.10 (2 H, m), 3.75-3.65 (2 H, m),
3.54-3.46 (2 H, m), 3.15-3.07 (1 H, m), 2.26 (2 H, t), 2.18-1.99 (2
H, m), 1.67-1.52 (4 H, m), 1.41-1.27 (4 H, m), 1.21 (6 H, d, J=6.2
Hz).
Step 8
Preparation of isopropyl
7-{(4R)-4-[(1E)-4,4-difluoro-3-oxo-4-phenylbut-1-en-1-yl]-2-oxo-1,3-oxazi-
nan-3-yl}heptanoate
A: oxidation of the alcohol: to a solution of DMSO
(Dimethylsulfoxide) (113 uL, 1.592 mmol, 1.2 eq) in DCM (5 mL) at
-78.degree. C. was added Oxalyl chloride (128 uL, 1.46 mmol, 1.1
eq) dropwise and the mixture was stirred at the temperature for 15
min. Isopropyl
7-[(4R)-4-(hydroxymethyl)-2-oxo-1,3-oxazinan-3-yl]heptanoate (400
mg, 1.327 mmol) in DCM (3 mL) was added via a cannula and the
mixture was stirred for an additional 15 min. Triethylamine (429
uL, 3.05 mmol, 2.3 eq) was then added in one portion and the
mixture stirred at -78.degree. C. for 30 min and allowed to warm to
0.degree. C. slowly and concentrated in vacuo. The mixture was
resuspended in ethyl acetate and filtered. The filtrate was
concentrated in vacuo to give the crude aldehyde isopropyl
7-[(4R)-4-formyl-2-oxo-1,3-oxazinan-3-yl]heptanoate with good
purity. .sup.1H NMR (400 MHz, CDCl.sub.3): .delta.9.69 (1 H, d),
5.04-4.96 (1 H, m), 4.29-4.23 (1 H, m), 4.16-4.00 (2 H, m),
3.79-3.71 (1 H, m), 3.02-2.94 (1 H, m), 2.30-2.24 (4 H, m),
1.66-1.58 (4 H, m), 1.42-1.28 (4 H, m), 1.24 (6 H, d).
B: Preparation of the sodium salt of dimethyl
(3,3-difluoro-2-oxo-3-phenylpropyl)phosphonate: to a solution of
dimethyl (3,3-difluoro-2-oxo-3-phenylpropyl)phosphonate (5.24 g,
18.84 mmol) in ether (50 mL) at rt was added sodium hydride (60%
oil dispersion, 791 mg, 19.78 mmol, 1.05 eq) portionwise and the
white suspension was stirred at rt for 1 h. The mixture was
filtered and the white solid washed with ether/hex. The solid thus
obtained was dried under high vacuum to give white powder.
C: Horner-Emmons-Smith reaction: to a solution of isopropyl
7-[(4R)-4-formyl-2-oxo-1,3-oxazinan-3-yl]heptanoate (207 mg, 0.691
mmol) in THF (3 mL) was added Zinc chloride (0.5M in THF, 1.52 mL,
0.76 mmol, 1.1 eq) followed by the sodium salt of dimethyl
(3,3-difluoro-2-oxo-3-phenylpropyl)phosphonate (270 mg, 0.898 mmol,
1.3 eq) as a solid and the mixture was heated to 60.degree. C. o/n
and concentrated. The residue was purified by column chromatography
(80% ethyl acetate/hexanes) to give the desired product isopropyl
7-{(4R)-4-[(1E)-4,4-difluoro-3-oxo-4-phenylbut-1-en-1-yl]-2-oxo-1,3-oxazi-
nan-3-yl}heptanoate as a light yellow oil. MS (+ESI): m/z 452
(M+1).sup.+.
Step 9
Compound 29: isopropyl
7-{(4R)-4-[(1E)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-1-yl]-2-oxo-1,3-o-
xazinan-3-yl}heptanoate
To a solution of catecholborane (107 mg) in toluene (1 mL) was
added (S)-2-methyl-CBS-oxaborolidine (1M in toluene, 0.89 mL) under
N.sub.2 at -78.degree. C. and the mixture was stirred at the
temperature for 1 h. Isopropyl
7-{(4R)-4-[(1E)-4,4-difluoro-3-oxo-4-phenylbut-1-en-1-yl]-2-oxo-
-1,3-oxazinan-3-yl}heptanoate (200 mg) in toluene (2 mL) was added
via a cannula slowly and the mixture was stirred for an additional
hour and quenched with 1N HCl. The mixture was allowed to warm to
room temperature and extracted with DCM (2.times.). The organic
layers were dried over Na.sub.2SO.sub.4 and filtered. The filtrate
was concentrated in vacuo and the residue purified by column
chromatography (80-100% ethyl acetate/hexanes) to give the title
compound. MS (+ESI): m/z 454 (M+1).sup.+.
EXAMPLE 15
7-{(4R)-4-[(1E)-4,4-difluoro-3-hydroxy-4-phenyl-but-1-en-yl]-2-oxo-1,3-oxa-
nzinan-3-yl}heptanoic acid
MS (-ESI): m/z 410 (M-1).sup.-.
##STR00037##
The isopropyl ester Compound 29 was first treated with a mixture of
LiOH in Methanol/water followed by acidification with 1N HCl and
extraction with ethyl acetate to give title compound. MS (-ESI):
m/z 410 (M-1).sup.-.
I. Effects of an EP4 Agonist on Intraocular Pressure (IOP) in
Rabbits and Monkeys.
Animals
Drug-naive, male Dutch Belted rabbits and female cynomolgus monkeys
are used in this study. Animal care and treatment in this
investigation are in compliance with guidelines by the National
Institute of Health (NIH) and the Association for Research in
Vision and Ophthalmology (ARVO) resolution in the use of animals
for research. All experimental procedures str approved by the
Institutional Animal Care and Use Committee of Merck and
Company.
Drug Preparation and Administration
Drug concentrations are expressed in terms of the active ingredient
(base). The compounds of this invention are dissolved in
physiological saline at 0.01, 0.001, 0.0001% for rabbit study and
0.05, 0.005% for monkey studies. Drug or vehicle aliquots (25 ul)
are administered topically unilaterally or bilaterally. In
unilateral applications, the contralateral eyes receive an equal
volume of saline. Proparacaine (0.5%) is applied to the cornea
prior to tonometry to minimize discomfort. Intraocular pressure
(IOP) is recorded using a pneumatic tonometer (Alcon Applanation
Pneumatonograph) or equivalent.
Analysis
The results are expressed as the changes in IOP from the basal
level measured just prior to administration of drug or vehicle and
represent the mean, plus or minus standard deviation. Statistical
comparisons are made using the Student's t-test for non-paired data
between responses of drug-treated and vehicle-treated animals and
for paired data between ipsilateral and contralateral eyes at
comparable time intervals. The significance of the date is also
determined as the difference from the "t-0" value using Dunnett's
"t" test. Asterisks represent a significance level of
p<0.05.
A. Intraocular Pressure Measurement in Rabbits
Male Dutch Belted rabbits weighing 2.5-4.0 kg are maintained on a
12-hour light/dark cycle and rabbit chow. All experiments are
performed at the same time of day to minimize variability related
to diurnal rhythm. IOP is measured before treatment then the
compounds of this invention or vehicle are instilled (one drop of
25 ul) into one or both eyes and IOP is measured at 30, 60, 120,
180, 240, 300, and 360 minutes after instillation. In some cases,
equal number of animals treated bilaterally with vehicle only are
evaluated and compared to drug treated animals as parallel
controls.
B. Intraocular Pressure Measurements in Monkeys.
Unilateral ocular hypertension of the right eye is induced in
female cynomolgus monkeys weighing between 2 and 3 kg by
photocoagulation of the trabecular meshwork with an argon laser
system (Coherent NOVUS 2000, Palo Alto, USA) using the method of
Lee at al. (1985). The prolonged increase in intraocular pressure
(IOP) results in changes to the optic nerve head that are similar
to those found in glaucoma patients.
For IOP measurements, the monkeys are kept in a sitting position in
restraint chairs for the duration of the experiment. Animals are
lightly anesthetized by the intramuscular injection of ketamine
hydrochloride (3-5 mg/kg) approximately five minutes before each
IOP measurement and one drop of 0.5% proparacaine was instilled
prior to recording IOP. IOP is measured using a pneumatic tonometer
(Alcon Applanation Tonometer) or a Digilab pneumatonometer (Bio-Rad
Ophthalmic Division, Cambridge, Mass., USA).
IOP is measured before treatment and generally at 30, 60, 124, 180,
300, and 360 minutes after treatment. Baseline values are also
obtained at these time points generally two or three days prior to
treatment. Treatment consists of instilling one drop of 25 ul of
the compounds of this invention (0.05 and 0.005%) or vehicle
(saline). At least one-week washout period is employed before
testing on the same animal. The normotensive (contralateral to the
hypertensive) eye is treated in an exactly similar manner to the
hypertensive eye. IOP measurements for both eyes are compared to
the corresponding baseline values at the same time point. Results
are expressed as mean plus-or-minus standard deviation in mm Hg.
The activity range of the compounds of this invention for ocular
use is between 0.01 and 100,000 nM.
II. Radioligand Binding Assays:
The assays used to test these compounds were performed essentially
as described in: Abramovitz M, Adam M, Boie Y, Carriere M, Denis D,
Godbout C, Lamontagne S, Rochette C, Sawyer N, Tremblay N M, Belley
M, Gallant M, Dufresne C, Gareau Y, Ruel R, Juteau H, Labelle M,
Ouimet N, Metters K M. The utilization of recombinant prostanoid
receptors to determine the affinities and selectivities of
prostaglandins and related analogs. Biochim Biophys Acta 2000 Jan.
17;1483(2):285-293 and discussed below:
Stable Expression of Prostanoid Receptors in the Human Embryonic
Kidney (HEK) 293(EBNA) Cell Line
Prostanoid receptor (PG) cDNAs corresponding to full length coding
sequences were subcloned into the appropriate sites of the
mammalian expression vector pCEP4 (Invitrogen) pCEP4PG plasmid DNA
was prepared using the Qiagen plasmid preparation kit (QIAGEN) and
transfected into HEK 293(EBNA) cells using LipofectAMINE@
(GIBCO-BRL) according to the manufacturers' instructions. HEK
293(EBNA) cells expressing the cDNA together with the hygromycin
resistance gene were selected in Dulbecco's Modified Eagle Medium
(DMEM) supplemented with 10% heat inactivated fetal bovine serum, 1
mM sodium pyruvate, 100 U/ml Penicillin-G, 100 .mu.g/ml
Streptomycin sulphate, 250 .mu.g/ml active GENETICIN.TM. (G418)
(all from Life Technologies, Inc./BRL) and 200 .mu.g/ml hygromycin
(Calbiochem). Individual colonies were isolated after 2-3 weeks of
growth under selection using the cloning ring method and
subsequently expanded into clonal cell lines. Expression of the
receptor cDNA was assessed by receptor binding assays.
HEK 293(EBNA) cells were grown in supplemented DMEM complete medium
at 37.degree. C. in a humidified atmosphere of 6% CO.sub.2 in air,
then harvested and membranes prepared by differential
centrifugation (1000.times.g for 10 min, then 160,000.times.g for
30 min, all at 4.degree. C.) following lysis of the cells by
nitrogen cavitation at 800 psi for 30 min on ice in the presence of
protease inhibitors (2 mM phenylmethylsulfonylfluoride, 10 .mu.M
E-64, 100 .mu.M leupeptin and 0.05 mg/ml pepstatin). The
160,000.times.g pellets were resuspended in 10 mM HEPES/KOH (pH
7.4) containing 1 mM EDTA at approximately 5-10 mg/ml protein by
Dounce homogenisation (Dounce A; 10 strokes), frozen in liquid
nitrogen and stored at -80.degree. C.
Prostanoid Receptor Binding Assays
Prostanoid receptor binding assays were performed in a final
incubation volume of 0.2 ml in 10 mM MES/KOH (pH 6.0) (EP subtypes,
FP and TP) or 10 mM HEPES/KOH (pH 7.4) (DP and IP), containing 1 mM
EDTA, 10 mM MgCl.sub.2 (EP subtypes) or 10 mM MnCl.sub.2 (DP, FP,
IP and TP) and radioligand [0.5-1.0 nM [.sup.3H]PGE.sub.2 (181
Ci/mmol) for EP subtypes, 0.7 nM [.sup.3H]PGD.sub.2 (115 Ci/mmol)
for DP, 0.95 nM [.sup.3H]PGF.sub.2.alpha. (170 Ci/mmol) for FP, 5
nM [.sup.3H]iloprost (16 Ci/mmol) for IP and 1.8 nM [.sup.3H]SQ
29548 (46 Ci/mmol) for TP]. EP.sub.3 assays also contained 100
.mu.M GTP.gamma.S. The reaction was initiated by addition of
membrane protein (approximately 30 .mu.g for EP.sub.1, 20 .mu.g for
EP.sub.2, 2 .mu.g for EP.sub.3, 10 .mu.g for EP.sub.4, 60 .mu.g for
FP, 30 .mu.g for DP, 10 .mu.g for IP and 10 .mu.g for TP) from the
160,000.times.g fraction. Ligands were added in dimethylsulfoxide
(Me.sub.2SO) which was kept constant at 1% (v/v) in all
incubations. Non-specific binding was determined in the presence of
1 .mu.M of the corresponding non-radioactive prostanoid.
Incubations were conducted for 60 min (EP subtypes, FP and IP) or
30 min (DP and TP) at 30.degree. C. (EP subtypes, DP, FP and TP) or
room temperature (IP) and terminated by rapid filtration through a
96-well Unifilter GF/C (Canberra Packard) prewetted in assay
incubation buffer without EDTA (at 4.degree. C.) and using a Tomtec
Mach III 96-well semi-automated cell harvester. The filters were
washed with 3-4 ml of the same buffer, dried for 90 min at
55.degree. C. and the residual radioactivity bound to the
individual filters determined by scintillation counting with
addition of 50 .mu.l of Ultima Gold F (Canberra Packard) using a
1450 MicroBeta (Wallac). Specific binding was calculated by
subtracting non-specific binding from total binding. Specific
binding represented 90-95% of the total binding and was linear with
respect to the concentrations of radioligand and protein used.
Total binding represented 5-10% of the radioligand added to the
incubation media.
The activity range of the compounds of this invention for bone use
is between 0.01 and 100,000 nM.
Bone Resorption Assays:
1. Animal Procedures:
For mRNA localization experiments, 5-week old Sprague-Dawley rats
(Charles River) are euthanized by CO.sub.2, their tibiae and
calvariae are excised, cleaned of soft tissues and frozen
immediately in liquid nitrogen. For EP.sub.4 regulation
experiments, 6-week old rats are given a single injection of either
vehicle (7% ethanol in sterile water) or an anabolic dose of
PGE.sub.2 (Cayman Chemical, Ann Arbor, Mich.), 3-6 mg/kg in the
same vehicle) intraperitoneally. Animals are euthanized at several
time points post-injection and their tibiae and calvariae, as well
as samples from lung and kidney tissues are frozen in liquid
nitrogen.
2. Cell Cultures
RP-1 periosteal cells are spontaneously immortalized from primary
cultures of periosteal cells from tibae of 4-week old
Sprague-Dawley rats and are cultured in DMEM (BRL, Gaithersburg,
Md.) with 10% fetal bovine serum (JRH Biosciences, Lenexa, Kans.).
These cells do not express osteoblastic phenotypic markers in early
culture, but upon confluence, express type I collagen, alkaline
phosphatase and osteocalcin and produce mineralized extracellular
matrix.
RCT-1 and RCT-3 are clonal cell lines immortalized by SV-40 large T
antigen from cells released from fetal rat calvair by a cmbination
collagenase/hyaluronidase digestion. RCT-1 cells, derived from
cells released during the first 10 minutes of digestion (fraction
I), are cultured in RPMI 1640 medium (BRL) with 10% fetal bovine
serum and 0.4 mg/ml G418 (BRL). These cells differentiate and
express osteoblastic features upon retinoic acid treatment. RCT-3
cells, immortalized from osteoblast-enriched fraction III cells,
are cultured in F-12 medium (BRL) with 5% Fetal bovine serum and
0.4 mg/ml G418. TRAB-11 cells are also immortalized by SV40 large T
antigen from adult rat tibia and are cultured in RPMI 1640 medium
with 10% FBS and 0.4 mg/ml G418. ROS 17/2.8 rat osteosarcoma cells
are cultured in F-12 containing 5% FBS. Osteoblast-enriched
(fraction i) primary fetal rat calvaria cells are obtained by
collagenase/hyaluronidase digestion of calvariae of 19 day-old rat
fetuses. See Rodan et al., Growth stimulation of rat calvaria
osteoblastic cells by acidic FGF, Endocrinology, 121, 1919-1923
(1987), which is incorporated by reference herein in its entirety.
Cells are released during 30-50 minutes digestion (fraction i) and
are cultured in F-12 medium containing 5% FBS.
P815 (mouse mastocytoma) cells, cultured in Eagles MEM with 10%
FBS, and NRK (normal rat kidney fibroblasts) cells, cultured in
DMEM with 10% FBS, are used as positive and negative controls for
the expression of EP.sub.4, respectively. See Abramovitz et al.,
Human prostanoid receptors: cloning and characterization. In:
Samulesson B. et al. ed) Advances in prostaglandin, Thrombosznes
and leukotriene research, vol. 23, pp. 499-504 (1995) and de Larco
et al., Epithelioid and fibroblastic rat kidney cell clones: EGF
receptors and the effect of mouse sarcoma virus transformation,
Cell Physiol., 94, 335-342 (1978), which are both incorporated by
reference herein in their entirety.
3. Northern Blot Analysis:
Total RNA is extracted from the tibial metaphysis or diaphysis and
calvaria using a guanidinium isothiocyanate-phenol-chloroform
method after pulverizing frozen bone samples by a tissue
homogenizer. See P. Chomczynski et al., Single-step method of RNA
isolation by acid guanidium thiocyanate-phenol-chloroform
extraction., Analyt Biochem, 162, 156-159 (1987), which is
incorporated by reference herein in its entirety. RNA samples (20
mg) are separated on 0.9% agarose/formaldehyde gels and transferred
onto nylon membranes (Boehringer Mannheim, Germany). Membranes are
prehybridized in Hybrisol I (Oncor, Gaithersburg, Md.) and 0.5
mg/ml sonicated salmon sperm DNA (Boehringer) at 42.degree. C. for
3 hours and are hybridized at 42.degree. C. with rat EP.sub.2 and
mouse EP.sub.4 cDNA probes labeled with [.sup.32P]dCTP (Amersham,
Buckinghamshire, UK) by random priming using the rediprime kit
(Amersham). After hybridization, membranes are washed 4 times in
2.times.SSC+0.1% SDS at room temperature for a total of 1 hour and
once with 0.2.times.SSC+0.1% SDS at 55.degree. C. for 1 hour and
then exposed to Kodak XAR 2 film at -70.degree. C. using
intensifying screens. After developing the films, bound probes are
removed twice with 0.1% SDS at 80.degree. C. and membranes are
hybridized with a human GAPDH (Glyceraldehyde 3-Phosphate
Dehydrogenase) cDNA probe (purchased from Clontech, Palo Alto,
Calif.) for loading control.
4. In-Situ Hybridization:
Frozen tibiae are sectioned coronally at 7 mm thickness and
sections are mounted on charged slides (Probe On Plus, Fisher
Scientific, Springfield, N.J.) and are kept at -70.degree. C. until
hybridization. cRNA probes are labeled with .sup.35S-UTPgS (ICN,
Costa Mesa, Calif.) using a Riboprobe II kit (Promega Madison,
Wis.). Hybridization is performed overnight at 50.degree. C. See M.
Weinreb et al., Different pattern of alkaline phosphatase,
osteopontin and osteocalcin expression in developing rat bone
visualized by in-situ hybridization, J. Bone Miner Res., 5, 831-842
(1990) and D. Shinar et al., Expression of alphav and beta3
integrin subunits in rat osteoclasts in situ, J. Bone Miner. Res.,
8, 403-414 (1993), which are both incorporated by reference herein
in their entirety. Following hybridization and washing, sections
are dipped in Ilford K5 emulsion diluted 2:1 with 6% glycerol in
water at 42.degree. C. and exposed in darkness at 4.degree. C. for
12-14 days. Slides are developed in Kodak D-19 diluted 1:1 with
water at 15.degree., fixed, washed in distilled water and mounted
with glycerol-gelatin (Sigma) after hematoxylin staining. Stained
sections are viewed under the microscope (Olympus, Hamburg,
Germany), using either bright-field or dark-field optics.
5. Expression of EP.sub.4 in Osteoblastic Cell Lines and in Bone
Tissue.
The expression of EP.sub.4 and EP.sub.2 mRNA is examined in various
bone derived cells including osteoblast-enriched primary rat
calvaria cells, immortalized osteoblastic cell lines from fetal rat
calvaria or from adult rat tibia and an osteoblastic osteosarcoma
cell line. Most of the osteoblastic cells and cell lines show
significant amounts of 3.8 kb EP.sub.4 mRNA, except for the rat
osteosarcoma cell line ROS 17/2.8. Consistent with this finding, in
ROS 17/2.8 cells PGE.sub.2 has no effect on intracellular cAMP,
which is markedly induced in RCT-3 and TRAB-11 cells. Treatment of
RCT-1 cells with retinoic acid, which promotes their
differentiation, reduces the levels of EP.sub.4 mRNA. NRK
fibroblasts do not express EP.sub.4 mRNA, while P815 mastocytoma
cells, used as positive controls, express large amounts of EP.sub.4
mRNA. In contrast to EP.sub.4 mRNA, none of the osteoblastic cells
and cell lines express detectable amounts of EP.sub.2 mRA in total
RNA samples. Expression of EP.sub.4 mRNA in osteoblastic cells,
EP.sub.4 is also expressed in total RNA isolated from tibiae and
calvariae of 5-week-old rats. In contrast, no EP.sub.2 mRNA is
found in RNA from tibial shafts.
6. PGE.sub.2 Induces the Expression of EP.sub.4 mRNA in RP-1
Periosteal Cells and in Adult Rat Tibiae
PGE.sub.2 enhances its own production via upregulation of
cyclooxygenase 2 expression in osteoblasts and in bone tissue thus
autoamplifying its own effects. PGE.sub.2 also increases the levels
of EP.sub.4 mRNA. RP-1 cells are immortalized from a primary
culture of adult rat tibia periosteum is examined. These cells
express osteoblast phenotypic markers upon confluence and form
mineralized bone matrix when implanted in nude mice. Similar to the
other osteoblastic cells examined, RP-1 periosteal cells express a
3.8 kb EP.sub.4 transcript. Treatment with PGE.sub.2 (10.sup.-6 M)
rapidly increases EP.sub.4 mRNA levels peaking at 2 hours after
treatment. PGE.sub.2 has no effect on EP.sub.4 mRNA levels in the
more differentiated RCT-3 cells pointing to cell-type specific
regulation of EP.sub.4 expression by PGE.sub.2. EP.sub.2 mRNA is
not expressed in RP-1 cells before or after treatment with
PGE.sub.2.
To examine if PGE.sub.2 regulates EP.sub.4 mRNA levels in vivo in
bone tissue, five-week-old male rats are injected with PGE.sub.2
(3-6 mg/Kg). Systemic administration of PGE.sub.2 rapidly increased
EP.sub.4 mRNA levels in the tibial diaphysis peaking at 2 h after
injection. A similar effect of PGE.sub.2 on EP.sub.4 mRNA is
observed in the tibial metaphysis and in calvaria. PGE.sub.2
induces EP.sub.4 mRNA levels in vitro in osteogenic periosteal
cells and in vivo in bone tissue in a cell type-specific and
tissue-specific manner. PGE.sub.2 does not induce EP.sub.2 mRNA in
RP-1 cells nor in bone tissue.
7. Localization of EP.sub.4 mRNA Expression in Bone Tissue
In situ hybridization is used in order to localize cells expressing
EP.sub.4 in bone. In control experiment (vehicle-injected) rats,
low expression of EP.sub.4 is detected in bone marrow cells.
Administration of a single anabolic dose of PGE.sub.2 increased the
expression of EP.sub.4 in bone marrow cells. The distribution of
silver grains over the bone marrow is not uniform and occurs in
clumps or patches in many areas of the metaphysis. Within the
tibial metaphysis, EP.sub.4 expression is restricted to the
secondary spongiosa area and is not seen in the primary spongiosa.
Hybridization of similar sections with a sense probe (negative
control) does not show any signal.
EP.sub.4 is expressed in osteoblastic cells in vitro and in bone
marrow cells in vivo, and is upregulated by its ligand,
PGE.sub.2.
8. Agonists of the Present Invention
Using standard methods for measuring agonist activity, the
following compounds are evaluated in cell cultures and in EP.sub.4
receptor cell-free systems to determine the agonist activity of the
compounds in terms of their EC.sub.50 value.
* * * * *