7-Oxabicycloheptane substituted diamide and its congener prostaglandin analogs

Abstract: 7-Oxabicycloheptane substituted amide prostaglandin analogs are provided having the structural formula wherein m is 0 to 4; A is -CH=CH- or -CH₂-CH₂-; n is 1 to 5; or a single bond; R is CO₂H, CO₂alkyl, CO₂alkali metal, CO₂polyhydroxyamine salt, -CH₂OH, wherein R⁴ and R⁵ are the same or different and are H, lower alkyl, hydroxy, lower alkoxy or aryl, at least one of R⁴ and R⁵ being other than hydroxy and lower alkoxy; p is 1 to 4; R¹ is H or lower alkyl; q is 1 to 12; R² is H or lower alkyl; and R³ is H, lower alkyl, lower alkenyl, lower alkynyl, aryl, arylalkyl, lower alkoxy, aryloxy, aryloxy, arylalkyloxy, amino, alkylamino arylamino, arylalkylamino, lower (wherein n′ is 0, 1 or 2), alkylaminoalkyl, arylaminoalkyl, arylalkylaminoalkyl, alkoxy­ alkyl, aryloxyalkyl or arylalkoxyalkyl. The compounds are cardiovascular agents useful, for ex­ ample, in the treatment of thrombotic disease.

Description: The present invention relates to 7-oxabicycloheptane substituted diamide and congener prostaglandin analogs which are cardiovascular agents useful, for example, in the treatment of thrombotic disease. EP-A-094 782, EP-A-107, 995 and US-A-4 456 617 describe 7-oxabicycloheptane substituted amino prostaglandin analogs which are also cardiovascular agents and which have non-carboxylic acid side chains of various structures. The compounds according to the present invention have the structural formula including all stereoisomers thereof, wherein n is 1 to 5; R is CO₂H, CO₂X, CO₂ alkali metal, or Z is (CH₂)q where q is 1 to 12 and may be substituted by one or more X or halo groups, and R³ is H, X, C₂₋₁₂ alkenyl, C₂₋₁₂ alkynyl, phenyl, phenyl-X-, X-O-, phenyl-OX-, phenoxy, amino, X-amino, phenylamino, phenyl-X-amino, (wherein n' is, 0, 1 or 2), X'-amino-X-, phenylamino-X-, phenyl-X'-amino-X-, X'-OX-, or phenyl-X'-O-X-, wherein the X and X' groups (as such or as part of another group) are same or different and are alkyl groups which contain 1 to 12 carbon atoms and may include a cycloalkyl substituent which contains 3 to 12 carbon atoms; the phenyl groups (as such or as part of another group) may be substituted with 1 or 2 X groups, and/or 1 or 2 hydroxy groups; According to another aspect of the present invention there is provided a compound having the structure including all stereoisomers thereof, wherein n is 1 to 5; R is CH₂OH or wherein R¹ and R² are the same or different and are H, X, hydroxy, X-O-, or phenyl, at least one of R¹ and R² being other than hydroxy and X-O- and n, X, Z and R³ being defined above The term "alkyl" as employed herein alone or as part of another group includes both straight and branched chain carbons, containing 1 to 12 carbons, preferably 1 to 7 carbons, such as methyl, ethyl, propyl, isopropyl, butyl, t-butyl, isobutyl, pentyl, hexyl, isohexyl, heptyl, 4,4-dimethylpentyl, octyl, 2,2,4-trimethylpentyl, nonyl, decyl, undecyl, dodecyl, the various branched chain isomers thereof. The term "cycloalkyl" as employed herein alone or as part of another group includes saturated cyclic hydrocarbon groups containing 3 to 12 carbons, preferably 3 to 8 carbons, which include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl and cyclododecyl. The term "C₂₋₁₂ alkenyl" as used herein refers to straight or branched chain radicals of 2 to 12 carbons, preferably 2 to 6 carbons in the normal chain, which include one double bond in the normal chain, such as 2-propenyl, 3-butenyl, 2-butenyl, 4-pentenyl, 3-pentenyl, 2-hexenyl, 3-hexenyl, 2-heptenyl, 3-heptenyl, 4-heptenyl, 3-octenyl, 3-nonenyl, 4-decenyl, 3-undecenyl, or 4-dodecenyl. The term "C₂₋₁₂ alkynyl" as used herein refers to straight or branched chain radicals of 2 to 12 carbons, preferably 2 to 6 carbons in the normal chain, which include one triple bond in the normal chain, such as 2-propynyl, 3-butynyl, 2-butynyl, 4-pentynyl, 3-pentynyl, 2-hexynyl, 3-hexynyl, 2-heptynyl, 3-heptynyl, 4-heptynyl, 3-octynyl, 3-nonynyl, 4-decynyl, 3-undecynyl, or 4-dodecynyl. Examples of the Z group include The term "halogen" or "halo" as used herein refers to chlorine, bromine, fluorine, and iodine, with chlorine or fluorine being preferred. Preferred are those compounds of formula I wherein n is 1 or 4, R is CO₂H or CH₂OH; Z is -CH₂-; and R³ is C₁₋₁₂ alkyl, such as pentyl, hexyl, or heptyl or C₁₋₁₂ alkoxy, such as pentoxy, C₁₋₁₂ alkylamino such as pentylamino or phenylthio C₁₋₁₂ alkyl, such as phenylthiomethyl. Other preferred values are set out below in claims 2-6 respectively. The compounds of formula I of the invention may be prepared as described below. As seen in reaction sequence "A", compounds of the invention R is CO₂ alkyl, that is are prepared by tosylating the lower alkyl ester containing the hydroxymethyl group, that is, compound II or IIA, (prepared as described in US-A-4,143,054) by reacting II or IIA with tosyl chloride in the presence of pyridine to form the corresponding tosylate IV which is subjected to a displacement reaction by dissolving IV in dimethylsulfoxide and heating to 90 to 100°C in the presence of potassium phthalimide to form the phthalimide V. The phthalimide V is then made to undergo selective hydrolysis by dissolving V in methylene chloride and ethanol under an inert atmosphere such as argon and reacting with anhydrous hydrazine to form the amine VI In reaction sequence "B", amides of the invention of structure IM wherein R¹ and R² are independently H, X or phenyl are prepared by treating ester IA to IH or IL or esters of IJ or IK with an amine of the structure E HNR¹R² . Compounds of the invention wherein R is tetrazolyl are prepared as described in reaction sequence "C" wherein alcohol XVII (prepared as described in US-A-4,143,054) is reacted with a Wittig reagent of the structure G in the presence of a base, such as potassium t-butoxide or sodium hydride-dimethyl sulfoxide employing a molar ratio of XVII: G of within the range of from about 1:1 to about 0.2:1 to form the hydroxymethyl compound IIC which may then be employed in reaction sequence "A" in place of compounds II or IIA to form compounds of the invention IN As seen in reaction sequence "D", compounds of the invention wherein R is CH₂OH may be prepared by reducing ester IA by treatment with sodium borohydride or lithium borohydride to form compounds of the invention IP Referring to reaction sequence "E", the ester IA can be converted to the free acid, that is, to by treating the esters with a base, such as lithium hydroxide, sodium hydroxide or potassium hydroxide to form the corresponding alkali metal salt, followed by neutralization with an acid, such as dilute hydrochloric acid or oxalic acid to form the acid compound of the invention IQ. In the reaction sequence identified as "F" where in Formula I, R is wherein R 2' is H or X, a solution of acid dissolved in an inert organic solvent such as benzene is treated with oxalyl chloride and a catalytic amount of dimethylformamide (DMF) and the mixture is stirred at room temperature under nitrogen. The resulting acid chloride is dissolved in an inert organic solvent such as tetrahydrofuran and the so-formed solution is added dropwise into a cold solution of amine hydrochloride H (wherein R 5' is H or X, employing a molar ratio of acid chloride: H of within the range of from 0.3:1 to 1:1 and preferably from 0.5:1) and triethylamine in aqueous tetrahydrofuran to form the hydroxamate IS. In reaction sequence "G" compounds of the invention wherein R³ is NH₂, that is IT may be prepared by reacting amine VI with hydantoic acid in the presence of carbonyldiimidazole and then hydrolyzing the resulting product to form IT. The tris(hydroxymethyl)aminomethane salt of any of the acids of formula I of the present invention is formed by reacting a solution of such acid in a inert solvent such as methanol with tri(hydroxymethyl)aminomethane and thereafter the solvent is removed by evaporation to leave the desired salt. To form the sulfinyl and/or sulfonyl analogs of compounds of formula I wherein R³ is the corresponding thio moiety such formula I compounds are subjected to oxidation, for example, by reacting same with sodium periodate or potassium monopersulfate (oxone) in the presence of methanol to form the sulfinyl derivative and/or sulfonyl derivative. Mixtures thereof may be separated by chromatography or other conventional separation procedures. The starting acid VII may be prepared by reacting the amino acid J or its acid chloride with acid chloride K (or its acid if the acid chloride of J is employed) in the presence of a strong base such as NaOH and water. The compounds of this invention have four centers of asymmetry as indicated by the asterisks in formula I. However, it will be apparent that each of the formulae set out above which do not include asterisks still represent all of the possible stereoisomers thereof. All of the various stereoisomeric forms are within the scope of the invention. The various stereoisomeric forms of the compounds of the invention, namely, cis-exo, cis-endo and all trans forms and stereoisomeric pairs may be prepared as shown in the working Examples which follow and by employing starting materials following the procedures as outlined in US-A-4,143,054. Examples of such stereoisomers are set out below. The nucleus in each of the compounds of the invention is depicted as for matter of convenience; it will also be appreciated that the nucleus in the compounds of the invention may be depicted as The compounds of this invention are cardiovascular agents useful as platelet aggregation inhibitors, such as in inhibiting arachidonic acid-induced platelet aggregation, e.g., for treatment of thrombotic disease such as coronary or cerebral thromboses, and in inhibiting bronchoconstriction. They are also selective thromboxane A₂ receptor antagonists and synthetase inhibitors, e.g., having a vasodilatory effect for treatment of myocardial ischemic disease, such as angina pectoris. The compounds of this invention may also be used in combination with a cyclic AMP phosphodiesterase (PDE) inhibitor such as theophylline or papaverine in the preparation and storage of platelet concentrates. The compounds of the invention can be administered orally or parenterally to various mammalian species known to be subject to such maladies, e.g., humans, cats, dogs, in an effective amount within the dosage range of 1 to 100 mg/kg, preferably 1 to 50 mg/kg and especially 2 to 25 mg/kg on a regimen in single or 2 to 4 divided daily doses. The active substance can be utilized in a composition such as tablet, capsule, solution or suspension containing 5 to 500 mg per unit of dosage of a compound or mixture of compounds of formula I. They may be compounded in conventional matter with a physiologically acceptable vehicle or carrier, excipient, binder, preservative, stabilizer, flavor, etc. as called for by accepted pharmaceutical practice. Also as indicated in the discussion above, certain members additionaly serve as intermediates for other members of the group. The compounds of the invention may also be administered topically to treat peripheral vascular diseases and as such may be formulated as a cream or ointment. The following Examples represent preferred embodiments of the present invention. Unless otherwise indicated, all temperatures are expressed in degrees Centigrade. Example 1 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxohexyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester A. N-Hexanoylglycine Glycine (7.5 g, 100 mmol) was dissolved in NaOH solution (NaOH:8 g, H₂O:50 ml) and cooled to 0°C. Et₂O (50 ml) was added and n-hexanoyl chloride (13.4 g, 100 mmol) was then added dropwise over 60 minutes at 0°C under vigorous stirring. The reaction was allowed to warm to room temperature and was stirred for 1 hour. 1N-NaOH (10 ml) was added and the layers were separated. The water layer was washed with Et₂O (20 ml x 2). The combined Et₂O layers were extracted with 1N-NaOH (20 ml). The combined water layers were acidified with concentrated HCl to pH 2 and the products were extracted with Et₂O (100 ml x 3). The combined Et₂O layers were washed with brine (50 ml) and dried over MgSO₄. Filtration and evaporation of solvent gave a colorless solid (16.2 g), which was crystallized from EtOAc (60 ml) to give colorless needle crystals (10.9 g, 63 mmol, 63%), m.p. 93-96°. TLC: silica gel, MeOH, CH₂Cl₂, HCOOH; 10, 89.5, 0.5, PMA R f =0.45. B. [1S-[1β,2α(5Z),3α,4β]]-7-[3-(Tosyloxymethyl)-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Tosyl chloride (4.256 g, 22.4 mmol) dissolved in CH₂Cl₂ (30 ml) was added dropwise to a magnetically stirred solution of [1S-[1β,2α(5Z),3α,4β]]-7-[3-(hydroxymethyl)-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester (prepared as described in U. S. Patent No. 4,143,054 (3 g, 11.2 mmol) in pyridine (30 ml) at 0°C. After completion of the addition, the reaction was warmed to room temperature and stirred overnight. The reaction was poured into ice/H₂O and stirred for 30 minutes. The products were extracted with EtOAc (80 ml x 3). The combined EtOAc layers were washed with 3N-HCl (40 ml x 3), saturated NaHCO₃, brine and dried over MgSO₄. Filtration and evaporation of solvent gave a white solid, which was crystallized from isopropyl ether to give the corresponding title tosylate in the form of needle crystals (4.23 g, 89%), m.p. 68-70°C. C. [1S-[1β,2α(5Z),3α,4β]]-7-[(3-(Aminomethyl)-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester The title B tosylate was subjected to a Gabriel synthesis to form the corresponding amino compound as described below. The potassium phthalimide used was purified prior to use by boiling 5 g thereof with 9 ml acetone for 15 minutes, filtering while hot and washing with 5 ml acetone. The remaining solid was dried in vacuo for 6 hours at 100°C prior to use. The title B tosylate (8.11 g, 19.2 mmol) and purified potassium phthalimide (6.4 g, 34.6 mmol, 1.8 equiv.) in dimethylsulfoxide (70 ml, Burdick & Jackson) were heated at 90-100°C for 2½ hours (checked by TLC Et₂O-pet ether 2:1, no tosylate remaining). After cooling to room temperature, water (90 ml) was added. Material began precipitating. The mixture was poured into ice water (∼350 ml) and stirred 30 minutes. The straw colored solid was harvested by filtration and washed with more water. The solid was dissolved in warm ethyl acetate (150 ml), washed with water (3 x 50 ml), dried (MgSO₄), filtered and freed of solvent in vacuo . The remaining solid (7.88 g) was recrystallized from isopropyl ether (∼150 ml) to give corresponding phthalimide (6.35 g, 83%) TLC. Et₂O-hexane 2:1, UV + vanillin R f = 0.38, trace 0.09. The above phthalimide (5.05 g, 13.8 mmol) was dissolved in distilled CH₂Cl₂ (24 ml) and distilled ethanol (104 ml) in an argon atmosphere. Anhydrous hydrazine (0.78 ml, 25.6 mmol) was added. The mixture was stirred at room temperature. After 8 hours an additional 0.2 ml of hydrazine was added and the mixture was stirred an additional 15 hours at room temperature. A white solid was removed by filtration and washed with more CH₂Cl₂. The filtrate was taken to dryness in vacuo (on the pump at end). Cold 0.5 N HCl solution (80 ml) was added. A small amount of white solid was removed by filtration and washed with additional 0.5 N HCl solution (80 ml). The acidic solution was washed with ether (2 x 100 ml) and then basified with solid K₂CO₃. The amine was extracted into CHCl₃ (3 x 100 ml), dried (MgSO₄) and freed of solvent in vacuo leaving a yellow oil. Ether (100 ml) was added to this oil. Some solid was insoluble. After cooling in an ice bath, the solid was removed by filtration. The solvent was removed from the filtrate in vacuo leaving title amine as a pale yellow oil (2.441 g, 71%). NMR spectra and TLC indicated some minor impurities. The material was used without further purification. D. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxohexyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A compound (260 mg, 1.5 mmol) was dissolved in distilled THF (12 ml) in an argon atmosphere. After cooling in an ice bath carbonyldiimidazole (CDI) (243 mg, 1.5 mmol) was added. The mixture was stirred cold for 1 hour and then at room temperature for 1 hour. The solution was cooled to 0°C and a solution of Part C amine (401 mg, 1.5 mmol) in THF (3 ml) was added. The mixture was left stirring overnight at room temperature. The solvent was removed in vacuo and the residue was dissolved in CHCl₃ (50 ml). This was washed with 1 N HCl (20 ml), 1 N NaOH (20 ml) and H₂O (20 ml), dried (MgSO₄) and freed of solvent in vacuo leaving a viscous oil. The oil was chromatographed on silica gel (30 g, Baker for flash chromatography), eluting with EtOAc and 1% MeOH in EtOAc to give title compound as an oil (425 mg, 67%). TLC: silica gel, 10% MeOH in CH₂Cl₂, vanillin R f = 0.48. Example 2 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxohexyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Example 1 methyl ester (420 mg, 0.994 mmol) was dissolved in distilled THF (40 ml) and water (8 ml) in an argon atmosphere. 1 N LiOH solution (9.5 ml) was added and the mixture was stirred at room temperature for 3-3/4 hours. After neutralization with 1 N HCl (9.5 ml), solid KCl was added and the layers were separated. The aqueous layer was reextracted with CHCl₃ (3 x 50 ml). The combined organic layers (THF + CHCl₃) were washed with saturated NaCl solution (2 x 25 ml), dried (MgSO₄), and freed of solvent in vacuo leaving a very viscous oil. This was chromatographed on silica gel (30 g, Baker for flash chromatography) eluting with 4% MeOH in CH₂Cl₂ to give material which crystallized, (358 mg, 88%). This was recrystallized from acetonitrile (∼10 ml) to give title acid, 248 mg, 61%, m.p. 119-121°C). TLC: silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f =0.37. Anal Calcd for C₂₂H₃₆O₅N₂: C, 64.68; H, 8.88; N, 6.86 Found: C, 64.67; H, 8.87; N, 6.86 Example 3 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[[(Butylamino)carbonyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester A. N-[(Butylamino)carbonyl]glycine, ethyl ester Glycine ethyl ester·HCl (5.58 g, 40 mmol) was suspended in distilled CH₂Cl₂ (20 ml). After cooling in an ice bath, distilled Et₃N (6.13 ml, 44 mmol) was added. Distilled n-butyl isocyanate (4.95 ml, 44 mmol) was added. The cooling bath was removed and the mixture was left stirring overnight at room temperature. Additional Et₃N (3.05 ml) was added and the mixture was stirred 3 more hours. After diluting with more CH₂Cl₂, the solution was washed with water (50 ml), 1N HCl (50 ml), saturated NaHCO₃ solution (50 ml) and water (50 ml). After drying (MgSO₄), the solvent was removed in vacuo leaving the title compound (7.641 g, 94%) which slowly crystallized. This was used without further purification. B. N-[(Butylamino)carbonyl]glycine Part A ethyl ester (3.378 g, 16.7 mmol) was dissolved in distilled THF (100 ml) and treated with 1N LiOH solution (40 ml). After stirring overnight at room temperature and acidifying with concentrated HCl, solid KCl was added. The layers were separated. The aqueous layer was reextracted with EtOAc (3 x 50 ml). The combined organic layers (THF and EtOAc) were washed with saturated NaCl solution (25 ml), dried (MgSO₄), and freed of solvent in vacuo leaving the title compound, as a white solid (2.81 g, 97%). C. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[[(Butylamino)carbonyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part B compound (174.2 mg, 1 mmol) was partially dissolved in distilled THF (8 ml) in an argon atmosphere. After cooling in an ice bath, carbonyl diimidazole (CDI) (162 mg, 1 mmol) was added. The mixture was stirred cold 1 hour and at room temperature 1½ hours (became a clear solution near the end of this time). The solution was cooled in an ice bath and a solution of chiral amine prepared in Example 1 Part C (267 mg, 1 mmol) in THF (3 ml) was added. The cooling bath was removed and the mixture was left stirring overnight at room temperature. The solvent was removed in vacuo . CHCl₃ (35 ml) was added to the residue. The solution was washed with 1N HCl (15 ml), 1N NaOH (15 ml) and H₂O (15 ml), dried (MgSO₄) and freed of solvent in vacuo leaving a very viscous oil (340 mg). This was chromatographed on silica gel (20 g, Baker for flash chromatography), eluting with EtOAc and 5% MeOH in EtOAc to give the title compound as a viscous oil (212 mg, 50%). TLC: silica gel, 5% MeOH in EtOAc, vanillin, R f =0.23. Example 4 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[[(Butylamino)carbonyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid Example 3 methyl ester (208 mg, 0.491 mmol) was dissolved in distilled THF (20 ml) and water (4.8 ml) in an argon atmosphere. 1N LiOH solution (4.9 ml) was added and the mixture was stirred at room temperature 5 hours. The mixture was neutralized with 1N HCl solution (4.9 ml) and solid KCl was added. The layers were separated. The aqueous layer was reextracted with CHCl₃ (3 x 25 ml). The combined organic layers (THF and CHCl₃) were washed with saturated NaCl solution (15 ml), dried (MgSO₄) and freed of solvent in vacuo leaving an oil. This was chromatographed on silica gel (18 g), eluting with 4% MeOH in CH₂Cl₂ to give the title compound (158 mg, 78.2%) as a white foam. TLC: silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f =0.28. Anal Calcd for C₂₁H₃₅O₅N₃·0.1 H₂O: C, 61.32; H, 8.63; N, 10.21 Found: C, 61.15; H, 8.74; N, 10.23 Preparation 1 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[Methyl(1-oxohexyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester A. N-Hexanoyl-N-methylglycine Sarcosine (1.78 g, 20 mmol) was dissolved in 1N NaOH solution (40 ml) and Et₂O (40 ml) was added. After cooling in an ice bath a solution of hexanoyl chloride (3.1 ml, 22 mmol) in Et₂O (10 ml) was added dropwise. The mixture was stirred cold for 1 hour. The pH was then adjusted to about 8 by adding 1N NaOH solution (about 3 ml) and the mixture was stirred at room temperature 45 minutes. NaOH solution was added to about pH 9-10. The layers were separated and the aqueous layer was washed with Et₂O (50 ml). After acidification of the aqueous layer with concentrated HCl and saturation with solid KCl, the product was extracted into CHCl₃ (3 x 70 ml). The combined CHCl₃ extracts were washed with saturated NaCl solution (25 ml), dried (MgSO₄), and freed of solvent leaving the title compound as an oil (3.78 g, quant.) which was used without further purification. B. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[Methyl(1-oxohexyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A compound (187 mg, 1 mmol) was dissolved in distilled THF (8 ml) in an argon atmosphere and cooled in an ice bath. Carbonyldiimidazole (CDI) (162 mg, 1 mmol) was added and the mixture was stirred cold for 1 hour and then for 1 hour at room temperature. After cooling in an ice bath, a solution of chiral amine prepared in Example 1 part C (267 mg, 1 mmol) in THF (3 ml) was added. The ice bath was removed and the mixture was stirred overnight at room temperature. The solvent was removed in vacuo . CHCl₃ (35 ml) was added to the residue. The solution was washed with 1N HCl (15 ml), 1N NaOH solution (15 ml) and H₂O (15 ml), dried (MgSO₄) and freed of solvent in vacuo leaving an oil (424 mg). This was chromatographed on silica gel (20 g, Baker for flash chromatography), eluting with EtOAc and 2% MeOH in EtOAc to give the title compound as an oil (252 mg, 57.7%). TLC: silica gel, 5% MeOH in EtOAc, vanillin; R f =0.46. Preparation 2 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[Methyl(1-oxohexyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Preparation 1 methyl ester (248 mg, 0.568 mmol) was dissolved in distilled THF (25 ml) and water (5 ml) in an argon atmosphere. 1N LiOH solution was added and the mixture was stirred at room temperature 4 hours. After neutralizing with 1N HCl solution (5.6 ml) and addition of solid KCl, the layers were separated. The aqueous layer was extracted with CHCl₃ (3 x 25 ml). The combined organic layers (THF + CHCl₃) were washed with saturated NaCl solution (15 ml), dried (MgSO₄) and freed of solvent in vacuo leaving an oil (242 mg). This was chromatographed on silica gel (20 g, Baker for flash chromatography) eluting with 4% MeOH in CH₂Cl₂ to give the title compound (191.8 mg, 79.9%) as a viscous oil. TLC: silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f =0.46. Anal Calcd for C₂₃H₃₈O₅N₂; C, 65.37; H, 9.06; N, 6.63 Found: C, 65.50; H, 9.10; N, 6.74 Example 5 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(Butoxycarbonyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester A. N-(Butoxycarbonyl)glycine ethyl ester Glycine ethyl ester·HCl (3.5 g, 25 mmol) was suspended in distilled CH₂Cl₂ (25 ml) in an argon atmosphere. After cooling to -40°C distilled Et₃N (7.65 ml, 55 mmol) was added followed by dropwise addition of a solution of distilled n-butyl chloroformate (3.2 ml, ∼25 mmol) in CH₂Cl₂ (10 ml). After stirring at -40° for 1 hour the mixture was left in a freezer (-5°C) overnight. The mixture was stirred at -5 to -10° for 1 hour. More CH₂Cl₂ was added followed by water (50 ml). The layers were separated. The organic layer was washed with 1N HCl (50 ml), saturated NaHCO₃ solution (50 ml) and water (50 ml), dried (MgSO₄), and freed of solvent in vacuo leaving 3.129 g of material. This was combined with material from a 5 mmol run and chromatographed on silica gel (100 g, Baker for flash chromatography), eluting with ether-hexane 1:1 to give the title compound as an oil (3.196 g, 52.5%). TLC: silica gel, Et₂O-hexane 1:1, PMA, R f =0.34. B. N-(Butoxycarbonyl)glycine The ethyl ester prepared in part A (3.141 g, 15.47 mmol) was dissolved in 100 ml distilled THF and treated with 1N LiOH solution (40 ml). The mixture was left stirring overnight at room temperature. After acidification with concentrated HCl and addition of solid KCl, the layers were separated. The aqueous layer was reextracted with EtOAc (3 x 50 ml). The combined organic layers (THF + EtOAc) were washed with saturated NaCl solution (25 ml), dried (MgSO₄) and freed of solvent in vacuo leaving the title compound (2.78 g, quant.) which slowly crystallized. C. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(Butoxycarbonyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester The acid prepared in part B (175.2 mg, 1 mmol) was dissolved in distilled THF (8 ml) in an argon atmosphere. After cooling in an ice bath carbonyldiimidazole (CDI) (162 mg, 1 mmol) was added. The mixture was stirred cold 1 hour and at room temperature 1 hour. The mixture was again cooled in an ice bath and a solution of chiral amine (prepared in Example I part C, 267 mg, 1 mmol) in THF (3 ml) was added. The cooling bath was removed and the mixture was left stirring overnight at voom temperature. The solvent was removed in vacuo . CHCl₃ (35 ml) was added. The solution was washed with 1N HCl (15 ml), 1N NaOH (15 ml) and H₂O (15 ml), dried (MgSO₄) and freed of solvent in vacuo . The remaining oil (433 mg) was chromatographed on silica gel (20 g of Baker for flash chromatography) eluting with EtOAc to give partially purified material (291 mg). This was rechromatographed on silica gel (20 g), eluting with Et₂O and 2% MeOH in Et₂O to give the title compound (172 mg, 40.5%) as an oil. Additional material (57 mg, 13.4%) was contaminated with a small amount of slower moving material. TLC: silica gel, 5% MeOH in Et₂O, vanillin, R f =0.32. Example 6 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(Butoxycarbonyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The methyl ester prepared in Example 5 (168 mg, 0.396 mmol) was dissolved in distilled THF (16 ml) and water (3.8 ml) in an argon atmosphere and 1N LiOH solution (3.9 ml) was added. The mixture was stirred at room temperature 5½ hours, then neutralized with 1N HCl solution (3.8 ml). After adding solid KCl the layers were separated. The aqueous layer was reextracted with CHCl₃ (3 x 25 ml). The combined organic layers (THF + CHCl₃) were washed with saturated NaCl solution (15 ml), dried (MgSO₄) and freed of solvent in vacuo leaving an oil (150 mg). This was chromatographed on silica gel (10 g, Baker for flash chromatography) eluting with 4% MeOH in CH₂Cl₂ to give 77 mg of material which appeared clean by TLC: silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f = 0.43. The material became partially crystalline on standing several days in the cold room. Trituration with Et₂O gave the title compound as a white solid (58.5 mg, 36%) m.p. 104-106°C. Anal Calcd for C₂₁H₃₄O₆N₂: C, 61.44; H, 8.35; N, 6.82 Found: C, 61.50; H, 8.37; N, 6.98 Example 7 [1S-[1β,2α(5Z),3α,4β]]-N-Methyl-7-[3-[[[[(1-Oxohexyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenamide 40% MeNH₂ in H₂O (2 ml) is added to a magnetically stirred solution of ester prepared in Example 1 (153 mg) in THF (14 ml) at room temperature. Stirring is continued overnight (17 hours) at room temperature. The reaction is concentrated in vacuo to give a crude product which is purified by silica gel column. The title compound is then obtained. Example 8 [1S-[1β,2α(5Z),3α(R),4β]]-7-[3-[[[1-Oxo-2-[(1-Oxohexyl)amino]propyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester A. (2R)-2-(Hexanoylamino)propionic acid D-alanine (20 mmol) and hexanoyl chloride (22 mmol) were reacted using the method as described in Preparation 1 Part A to give the title compound as a white crystalline material (2.45 g, 65.5%) after recrystallization from isopropyl ether (20 ml), m.p. 82-95°C. B. [1S-[1β,2α(5Z),3α(R),4β]]-7-[3-[[[1-Oxo-2-[(1-Oxohexyl)amino]propyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A acid compound (1 mmol) and chiral amine prepared as described in Example 1 Part C (1 mmol) were coupled using CDI (1 mmol) as described in Preparation 1 Part B. The crude product was chromatographed on silica gel (Baker for flash chromatography) eluting with 2-4% MeOH in Et₂O. The eluted product was triturated with Et₂O to give the title methyl ester as a white solid (217 mg, 50%). TLC: silica gel, 5% MeOH in Et₂O, vanillin R f =0.47. Example 9 [1S-[1β,2α(5Z),3α(R),4β]]-7-[3-[[[1-Oxo-2-[(1-Oxohexyl)amino]propyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Example 8 methyl ester (215 mg, 0.49 mmol) was hydrolyzed with LiOH solution in a THF-water mixture as described in Preparation 2. The viscous product was dissolved in EtOAc (∼2-3ml). On standing crystalline material was deposited. This was harvested by filtration and washed with Et₂O to give title acid (166.6 mg, 80%), m.p. 101-103°. Anal Calcd for C₂₃H₃₈O₅N₂: C, 65.37; H, 9.06; N, 6.63 Found: C, 65.30; H. 9.16; N, 6.46 TLC: Silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f =0.48. [α] D =+25.5° (c=1.37, MeOH). Example 10 [1S-[1β,2α(5Z),3α(S),4β]]-7-[3-[[[1-Oxo-2-[(1-oxohexyl)amino]propyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester A. (2S)-2-(Hexanoylamino)propionic acid L-Alanine (10 mmol) and hexanoyl chloride (11 mmol) were reacted using the method described in Preparation 1 Part A to give the title compound as a white crystalline material (1.091 g, 58%) after recrystallization from isopropyl ether (∼6 ml). B. [1S-[1β,2α(5Z),3α(S),4β]]-7-[3-[[[1-Oxo-2-[(1-oxohexyl)amino]propyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A compound (1 mmol) and chiral amine (prepared as described in Example 1 Part C) (1 mmol) were coupled using CDI (1 mmol) as described in Preparation 1 Part B. The crude product was chromatographed on silica gel (Baker for flash chromatography) eluting with 2% MeOH in Et₂O to give clean title methyl ester (178 mg, 41%) and additional material (129 mg, 29%) contaminated with material moving slower on TLC. TLC: silica gel, 5% MeOH in Et₂O, vanillin, R f =0.55. Slower moving contaminant R f =0.34. Example 11 [1S-[1β,2α(5Z),3α(S),4β]]-7-[3-[[[1-Oxo-2-[(1-oxohexyl)amino]propyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Example 10 methyl ester (175 mg, 0.40 mmol) was hydrolyzed with LiOH in a THF-water mixture as described in Preparation 2. The viscous product was dissolved in EtOAc (2 ml). Crystalline material was deposited on standing. This was harvested by filtration and washed with cold Et₂O to give the title compound (129 mg, 76%), m.p. 104-106°C. Anal Calcd for C₂₃H₃₈O₅N₂: C, 65.37; H, 9.06; N, 6.63 Found: C, 65.53; H, 9.26; N, 6.50 TLC: silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f =0.48. [α] D =-40°(C=1.29, MeOH) Example 12 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[2-Methyl-2-[(1-Oxohexyl)amino]-1-oxopropyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester A. 2-(Hexanoylamino)-2-methylpropionic acid 2-Aminoisobutyric acid (2.0 g, 19.4 mmol) and n-hexanoyl chloride (3.0 g, 22.4 mmol) were reacted in the presence of NaOH (1.6 g, 40 mmol) in a mixture of ether and water using the method described in Preparation 1 Part A. The title compound (1.90 g, 49%) was obtained after crystallization from benzene, m.p. 141-143°C. B. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[2-Methyl-2-[(1-Oxohexyl)amino]-1-oxopropyl]amino]methyl]-7-oxabicyclo [2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A compound (1 mmol) was reacted with CDI (1 mmol) and then with chiral amine prepared as described in Example 1 Part C (1 mmol) employing the method described in Example 1 Part D. The crude product was chromatographed on silica gel (25 g, Baker for flash chromatography), eluting with 2% MeOH in Et₂O to give title ester (235 mg, 52%) as white crystalline material. TLC: silica gel, 5% MeOH in Et₂O, vanillin, R f =0.46. Example 13 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[2-Methyl-2-[(1-oxohexyl)amino]-1-oxopropyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Example 12 methyl ester (231 mg, 0.51 mmol) was hydrolyzed with LiOH in a water-THF mixture as described in Preparation 2. The product was crystallized from ethyl acetate (∼4 ml) to give title acid (154.2 mg, 69%), m.p. 81-87°C. TLC: silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f =0.42. [α[ D = -10.1° (c=1.63, MeOH) Anal Calcd for C₂₄H₄₀O₅N₂: C, 66.02; H, 9.24; N, 6.42 Found: C, 65.92; H, 9.37; N, 6.46 Example 14 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxoheptyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester A. 2-(Heptanoylamino)acetic acid Glycine (1.5 g, 20 mmol) and heptanoyl chloride (22 mmol) were reacted in the presence of NaOH (40 mmol) in a mixture of water and ether using the method described in Preparation 1. The crude product was recrystallized from EtOAc (30 ml) to give title compound (2.71 g, 72%), m.p. 98-100°C. B. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxoheptyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A compound (1 mmol) was reacted with CDI (1 mmol) and then with chiral amine (1 mmole) prepared as described in Example 1 Part C employing the method described in Preparation 1 Part B. The crude product was chromatographed on silica gel (25 g, Baker for flash chromatography) eluting with EtOAc and 2% MeOH in EtOAc to give title ester (270 mg, 62%) as an oil. TLC: silica gel, 5% MeOH in EtOAc, vanillin, R f =0.45. Example 15 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxoheptyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Example 14 methyl ester (265 mg, 0.607 mmol) was hydrolyzed with LiOH in a water-THF mixture as described in Preparation 2. The crude crystalline product was recrystallized from EtOAc (4 ml) to give title acid (204 mg, 80%), m.p. 114-116°C. TLC:Silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f =0.40 [α] D = -6.6°(C=1.15, MeOH). Anal Calcd for C₂₃H₃₈O₅N₂: C, 65.37; H, 9.06; N, 6.42 Found: C, 65.38; H, 9.01; N, 6.64 Example 16 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[(1-Oxo-3-[(1-oxopentyl)amino]propyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester A. 3-(Pentanoylamino)propionic acid β-Alanine (20 mmol) was reacted with valeryl chloride (22 mmol) in the presence of NaOH (40 mmol) in a mixture of H₂O and ether using the method described in Preparation 1. The crude crystalline product (2.75 g, 79%) was recrystallized from a mixture of isopropyl ether (150 ml) and ethyl acetate (10 ml) to give title acid (1.51 g, 44%), m.p. 73-76°C. B. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[(1-Oxo-3-[(1-oxopentyl)amino]propyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A acid (1 mmol) was reacted with carbonyl diimidazole (1 mmol) followed by [1S-[1β,2α(5Z),3α,4β]]-7-[3-(aminomethyl)-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester (prepared as described in Example 1 Part C (1 mmole)). The crude product was chromatographed on silica gel (25 g, Baker for flash chromatography) eluting with 5-10% MeOH in Et₂O to give title product as a white solid (304 mg, 72%). TLC: silica gel, 10% MeOH in Et₂O, vanillin, R f =0.47. Example 17 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[1-Oxo-3-[(1-oxopentyl)amino]propyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Example 16 methyl ester (301 mg, 0.71 mmol) was hydrolyzed with LiOH in a THF-H₂O mixture as described in Preparation 2 to give a white solid (249 mg). This was recrystallized from EtOAc (∼4 ml) to give title acid (218 mg, 75%), m.p. 113-115°. TLC: silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f =0.28 Anal Calcd for C₂₂H₃₆O₅N₂: C, 64.68; H, 8.88; N, 6.86 Found: C, 64.65; H, 8.85; N, 6.87 [α] D = -8.4° (c=1.0, MeOH) Example 18 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxopropyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid Following the procedure of Examples 1 and 2 except substituting propanoyl chloride for hexanoyl chloride, the title compound is obtained. Example 19 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxoethyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid Following the procedure of Examples 1 and 2 except substituting acetyl chloride for 6-hexanoyl chloride, the title compound is obtained. Example 20 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxo-2-butenyl)amino]acetyl]amiio]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid Following the procedure of Examples 1 and 2 except substituting 2-butenoyl chloride for hexanoyl chloride, the title compound is obtained. Example 21 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxo-3-butynyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid Following the procedure of Examples 1 and 2 except substituting 3-butynoyl chloride for hexanoyl chloride, the title compound is obtained. Example 22 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[[(Pentylamino)carbonyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid Following the procedure of Examples 3 and 4 except substituting n-pentyl isocyanate for n-butyl isocyanate, the title compound is obtained. Example 23 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[[(Phenylamino)carbonyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid Following the procedure of Examples 3 and 4 except substituting phenyl isocyanate for n-butyl isocyanate, the title compound is obtained. Example 24 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(Phenylcarbonyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid Following the procedure of Examples 1 and 2 except substituting benzoyl chloride for hexanoyl chloride, the title compound is obtained. Example 25 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(Benzyloxycarbonyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid Following the procedure of Examples 5 and 6 except substituting benzyl chloroformate for n-butyl chloroformate, the title compound is obtained. Example 26 [1S-[1β,2α(Z),3α,4β]]-6-[3-[[[(1-Oxohexyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-1-(1H-tetrazol-5-yl)-4-hexene A. [1S-[1β,2α(Z),3α,4β]]-6-[3-Hydroxymethyl-7-oxabicyclo[2.2.1]hept-2-yl]-1-(1H-tetrazol-5-yl)-4-hexene To 5.5 g (11.8 mmole) of triphenyl-4-(1H-tetrazol-5-yl)butyl phosphonium bromide in 100 ml of tetrahydrofuran (THF) at 0° is added 2.78 g (23.6 mmole) potassium t-butoxide. The reaction is stirred at 25° for 30 minutes and (exo)octahydro-5,8-epoxy-1H-benzopyran-3-ol, (2 g, 11.8 mmole, prepared as described in U. S. Patent No. 4,143,054) is added in 30 ml of THF. The reaction is stirred for 2 hours and quenched with dilute aqueous HCl. The aqueous layer is extracted with 250 ml of ethyl acetate. The combined organic solutions are evaporated in vacuo , diluted with 500 ml of a 5% NaHCO₃ solution, washed with 100 ml of ether, acidified with dilute HCl to pH 3, and extracted with three 500 ml portions of ethyl acetate. The combined organic solutions are dried over anhydrous MgSO₄, and purified by silica chromatography using a 5% methanol in methylene chloride eluant to provide 2 g of title A compound. B. [1S-[1β,2α(5Z),3α,4β]]-6-[3-[[[(1-Oxohexyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-1-(1H-tetrazol-5-yl)-4-hexene Following the procedure of Examples 1 and 2 except substituting the Part A compound for the hydroxymethyl compound used in Example 1 Part B, the title compound is obtained. Example 27 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxohexyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-N-hydroxy-N-methyl-5-heptenamide A solution of Example 2 acid (0.82 mmole) in dry benzene (5.0 ml) is treated with oxalyl chloride (1 ml; 11.24 mmole or 13.7 eq.) and a drop of DMF, and stirred at room temperature under nitrogen for 2 hours. The excess oxalyl chloride and solvent are blown off by a stream of nitrogen while heating the reaction flask in a warm water bath and the oil obtained dried in vacuo (oil pump) for 1 hour. The residual acid chloride is dissolved in dry tetrahydrofuran (1.5 ml) and added dropwise into a cold solution (0°, ice-water) of 98% methylhydroxylamine hydrochloride (139.8 mg; 1.64 mmole; 2 eq.) and triethylamine (0.34 ml; 2.46 mmole; 3 eq.) in tetrahydrofuran (2 ml) and water (2.0 ml). The mixture is stirred at 0° under nitrogen for 30 minutes and at room temperature for 5.5 hours, diluted with water (10 ml) and extracted twice with dichloromethane (50 ml). The organic extract is washed with 1 N HCl (10 ml), 5% NaHCO₃ (5 ml) and water (10 ml), dried (anhydrous MgSO₄), filtered and evaporated to dryness giving the crude product, which is purified by silica gel column to afford the title compound. Example 28 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxononyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester A. N-Nonanoyl glycine Glycine (20 mmol) was reacted with nonanoyl chloride (22 ml) in the presence of NaOH (40 mmol) in a mixture of water and ether as described in Example 1 Part A. The crude crystalline product (4.25 g) was recrystallized from ethyl acetate (40-50 ml) to give the title compound (3.42 g, 79.5%), m.p. 106-109°C. B. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxononyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A compound (1 mmol) was reacted with carbonyldiimidazole (1 mmol) followed by Examle 1 Part C chiral amine as described in Example 1 Part D. The crude product was chromatographed on silica gel (30 g, Baker for flash chromatography) eluting with EtOAc and 2% MeOH in EtOAc to give the title ester (305 mg, 65.6%) as a colorless oil. TLC: silica gel, 2% MeOH in EtOAc, vanillin, R f =0.39. Example 29 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxononyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Example 28 methyl ester (302 mg, 6.5 mmol) was hydrolyzed with LiOH in a THF-H₂O mixture as described in Example 2 to give crystalline material. This was recrystallized from EtOAc (about 8 ml) to give title acid (233 mg, 79.5%), m.p. 121-127°C. TLC: silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f =0.44 [α] D = -6.0° (c=1, MeOH) Anal Calcd for C₂₅H₄₂O₅N₂: C, 66.64; H, 9.39; N, 6.22 Found: C, 66.27; H, 9.32; N, 6.28 Example 30 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxooctyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester A. N-Octanoylglycine Glycine (20 mmol) was reacted with octanoyl chloride (22 mmol) in the presence of NaOH (40 mmol) in a mixture of water and ether using the method described in Example 1 Part A. The crude crystalline product (3.06 g, 76%) was recrystallized from EtOAc (15 ml) to give the title compound (1.11 g, 28%), m.p. 105-107°C. B. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxooctyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A compound (1 mmol) was reacted with carbonyldiimidazole (1 mmol), followed by Example 1 Part C chiral amine (1 mmol) as described in Example 1 Part D. The crude product was chromatographed on silica gel (30 g, Baker for flash chromatography), eluting with EtOAC and 2% MeOH in EtOAc to give title ester as a colorless oil (330 mg, 73%). TLC: silica gel, 2% MeOH in EtOAc, vanillin, R f =0.26 Example 31 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxooctyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Example 30 methyl ester (327 mg, 0.726 mmol) was hydrolyzed with LiOH in a THF-H₂O mixture as described in Example 2 to give a white solid (306 mg). This was recrystallized from EtOAc (10 ml) to give title acid (262 mg, 83%), m.p. 129-131°C. TLC: silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f = 0.44. [α] D = -6.0 (c=0.96, MeOH) Anal Calcd for C₂₄H₄₀O₅N₂: C, 66.02; H, 9.24; N, 6.42 Found: C, 66.02; H. 9.16; N, 6.39 Example 32 [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxo-4-phenyl)butyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid A. 4-Phenylbutanoyl glycine ethyl ester 4-Phenylbutyric acid (2.46 g, 15 mmol) was dissolved in distilled THF (70 ml) in an argon atmosphere. After cooling in an ice bath, carbonyldiimidazole (CDI) (2.43 g, 1.5 mmol) was added and the mixture was stirred cold 1 hour and at room temperature 1 hour. The mixture was then cooled and glycine ethyl ester·HCl (2.09 g, 15 mmol) and distilled Et₃N (2.1 ml, 15 mmol) were added. The mixture was left stirring overnight at room temperature. After removal of the solvent in vacuo , Et₂O (200 ml) was added. The solution was washed with 1N HCl (70 ml), 0.5 N NaOH (70 ml) and saturated NaCl solution (70 ml), dried (MgSO₄) and freed of solvent in vacuo leaving title compound (3.13 g, 84%) as white crystalline material. TLC: silica gel, Et₂O, UV; R f : 0.58. B. 4-Phenylbutanoyl glycine The Part A ester (3.07 g, 12.3 mmol) was hydrolyzed with NaOH (5 g, 125 mmol) in water (60 ml). After stirring at room temperature 6 hours, neutral material was removed by washing with Et₂O (2 x 50 ml). The aqueous solution was then acidified with concentrated HCl solution. The product was extracted into CHCl₃ (3 x 60 ml), dried (MgSO₄) and freed of solvent in vacuo leaving a white solid. This was recrystallized from EtOAc (10 ml) to give title compound (2.18 g, 80%), m.p. 99-101°C. C. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxo-4-phenyl)butyl]amino]acetyl]amino]-methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part B acid (1 mmol) was reacted with CDI (1 mmol) and then with Example 1 Part C chiral amine (1 mmol) as described in Preparation 1 Part B. The crude product was chromatographed on silica gel (26 g, Baker for flash chromatography) eluting with EtOAc and 2% MeOH in EtOAc to give title compound (337 mg, 72%) as an oil. TLC: silica gel, 2% CH₃OH in EtOAc, Ce(SO₄)₂, R f =0.40. D. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxo-4-phenyl)butyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Part C methyl ester (336 mg, 0.71 mmol) was hydrolyzed with LiOH in a water-THF mixture as described in Preparation 2. The crude crystalline product (300 mg) was recrystallized from a mixture of MeOH and EtOAc to give title compound (247.8 mg, 76%), m.p. 114-116°C, TLC: silica gel, 2% CH₃OH in EtOAc, Ce(SO₄)₂ R f 0.20 [α] D = -5.8 (C=1.7, CH₃OH) Anal calcd for C₂₆H₃₆N₂O₅: C, 68.40; H, 7.95; N, 6.14 Found: C, 68.45; H, 8.03; N, 6.11 Example 33 [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Phenylthio)acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid A. (Phenylthio)acetyl glycine ethyl ester The title ethyl ester was prepared from thiophenoxy acetic acid (15 mmol) and the ethyl ester of glycine·HCl using carbonyldiimidazole (CDI) as described in Example 32, Part A giving 2.95 g (78%) of solid. B. (Phenylthio)acetyl glycine The Part A ethyl ester was hydrolyzed with aqueous NaOH as described in Example 32 Part B to give the title acid (1.041 g, 92%) as a crystalline material. C. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Phenylthio)acetyl]amino]acetyl]amino]methyl]-7-oxobicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester The Part B acid (1.5 mmol) was reacted with CDI (1.5 mmol) followed by Example 1 Part C chiral amine (1.5 mmol) as described in Preparation 1 Part B. The crude product was chromatographed on silica gel (30g, Baker for flash chromatography) eluting with EtOAc and 2% MeOH in EtOAc to give title ester as a solid, 523 mg, 73%. TLC: silica gel, 5% MeOH in EtOAc, UV + vanillin, R f : 0.48. D. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Phenylthio)acetyl]amino]acetyl]amino]methyl]-7-oxobicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Part C methyl ester (467 mg, 0.98 mmol) was hydrolyzed with 1N LiOH (2 equivalents) as described in Preparation 2. The crude product was recrystallized from EtOAc (10 ml) to give title acid (419 mg, 93%), m.p. 126-128°C. [α] D = -5.4° (c=0.8, MeOH). TLC: silica gel, 10% MeOH in CH₂Cl₂ + HOAc (3 drops/10 ml), UV + vanillin, R f 0.51. Anal Calcd for C₂₄H₃₂O₅N₂S: C, 62.58; H, 7.00; N, 6.08; S, 6.96 Found: C, 62.49; H, 7.14; N, 6.02; S, 6.91 Example 34 [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[3-(4-Hydroxyphenyl)1-oxopropyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid A. 3-(4-Hydroxyphenyl)propanoyl glycine ethyl ester 3-(4-Hydroxyphenyl)propionic acid (2.49 g, 15 mmol) was reacted with glycine ethyl ester hydrochloride in the presence of CDI and Et₃N as described in Example 32 Part A. After removal of the solvent the residue was dissolved in CHCl₃ and washed with 1N HCl, saturated NaHCO₃ solution and saturated NaCl solution. After drying (MgSO₄) and removal of the solvent in vacuo crude title ester remained (2.44 g) as a viscous oil. NMR indicated this contained a major impurity but it was used without further purification. B. 3-(4-Hydroxyphenyl)propanoyl glycine Crude Part A ethyl ester was hydrolyzed with NaOH in water as described in Example 32 Part B to give a white solid (1.37 g). This was recrystallized from EtOAc·MeOH to give the title solid (0.98 g, 29% from starting acid). C. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[3-(4-Hydroxyphenyl)-1-oxopropyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Example 1, Part C chiral amine (401 mg, 1.5 mmol) was dissolved in distilled THF (20 ml) in an argon atmosphere. Part B acid (346 mg, 1.55 mmol) was added and the mixture was cooled in an lce bath. Dicyclohexylcarbodiimide (DCC) (319 mg, 1.55 mmol) was added and the mixture was stirred cold 20 minutes and at room temperature overnight. 1N HCl (4 drops) was added and after stirring 10 minutes the solvent was removed in vacuo . EtOAc (8 ml) was added to the residue. After cooling in an ice bath the solid was removed by filtration and washed with cold EtOAc (∼10 ml). The filtrate was freed of solvent in vacuo and the remaining material was chromatographed on silica gel (35 g, Baker for flash chromatography) eluting with EtOAc and 3% MeOH in EtOAc to give title ester (243 mg, 34%) as a viscous material. TLC: silica gel, 8% MeOH in EtOAc, UV + vanillin, R f = 0.45. D. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[3-(4-Hydroxyphenyl)-1-oxopropyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Part C methyl ester (243 mg, 0.51 mmol) was dissolved in distilled THF (20 ml) and water (2 ml) in an argon atmosphere and treated with 1N LiOH solution (3 ml). The reaction appeared complete by TLC in 1 hour and at 2 hours was worked up as described in Preparation 2. The product (212 mg, 90%) was a brittle foam which failed to crystallize. [α] D = -5.7° (c=0.65, MeOH). TLC: silica gel, 10% MeOH in CH₂Cl₂ + HOAc (3 drops/10ml), UV + vanillin. R f = 0.32. Anal Calcd for C₂₅H₃₄O₆N₂: C, 65.48; H. 7.47; N, 6.11 Found: C, 65.34; H, 7.59; N, 6.09 Example 35 [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[(Phenoxyacetyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid A. Phenoxyacetyl glycine Glycine (20 mmol) was reacted with distilled phenoxyacetyl chloride (22 mmol) in the presence of NaOH (40 mmol) in a mixture of water and ether as described in Preparation 1 Part A. The crude product was recrystallized from EtOAc (15 ml) to give title acid (2.38 gm, 57%). B. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[(Phenoxyacetyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A acid (1.5 mmol) was reacted with CDI (1.5 mmol), followed by Example 1 Part C chiral amine (1.5 mmol) as described in Preparation 1, Part B. The crude product was chromatographed on silica gel (25 g, Baker for flash chromatography) eluting with EtOAc and 2% MeOH in EtOAc to give title ester as a white solid (463 mg, 67%). TLC: silica gel, 5% MeOH in EtOAc, UV + vanillin, R f = 0.53. C. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[(Phenoxyacetyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Part B methyl ester (463 mg, 1.01 mmol) was hydrolyzed with 1N LiOH (2 equivalents) in a THF-H₂O mixture as described in Preparation 2 to give a white solid. This was recrystallized from EtOAc (20 ml) containing a few drops of MeOH to give title acid (380 mg, 84.6%). [α] D = -5.9° (c=0.68, MeOH). TLC: Silica gel, 10% MeOH in CH₂Cl₂ + HOAc (3 drops/10 ml), UV + vanillin, R f = 0.57. Anal Calcd for C₂₄H₃₂O₆N₂: C, 64.85; H. 7.26; N, 6.30 Found: C, 64.94; H, 7.34; N, 6.26 Example 36 [1S-[1α,2β(5Z),3β,4α]]-7-[3-[[[[(1-Oxo-3-phenylpropyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid A. 3-Phenylpropanoyl glycine Glycine (1.5 g, 20 mmol) and hydrocinnamoyl chloride (3.37 g, 22 mmol) were reacted in the presence of NaOH (40 mmol) in a mixture of water and ether using the method described in Preparation 1 Part A. The crude product was extracted into chloroform, dried (MgSO₄) and freed of solvent in vacuo leaving a near white solid (3.53 g, 85%). This was recrystallized from EtOAc (13 ml) to give title compound (2.66 g, 64%) m.p. 112-114°C. B. [1S-[1α,2β(5Z),3β,4α]]-7-[3-[[[[(1-Oxo-3-phenylpropyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A acid (1 mmol) was reacted with CDI (1 mmol) and then with Example 1 Part C chiral amine (1 mmol) as described in Preparation 1 Part B. The crude product was chromatographed on silica gel (25 g, Baker for flash chromatography), eluting with 2% MeOH in EtOAc to give title compound (330 mg, 72%) as an oil. TLC: silica gel, 2% MeOH in EtOAc, vanillin R f = 0.29. C. [1S-[1α,2β(5Z),3β,4α]]-7-[3-[[[[(1-Oxo-3-phenylpropyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Part B methyl ester (330 mg, 0.72 mmol) was hydrolyzed with LiOH in a water-THF mixture as described in Preparation 2. The crude crystalline product was recrystallized from EtOAc (12 ml) to give title compound (264 mg, 82.8%) m.p. 119-122°C. TLC: silica gel, 8% MeOH in CH₂Cl₂, UV and vanillin, R f = 0.29. [α] D = -5.9 (c=1.1, MeOH). Anal Calcd for C₂₅H₃₄O₅N₂: C, 67.85; H, 7.74; N, 6.33 Found: C, 67.62; H, 7.65; N, 6.22 Example 37 [1S-[1α,2β(5Z),3β,4α]]-7-[3-[[[[(1-Oxo-5-phenylpentyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid A. 5-Phenylpentanoyl glycine ethyl ester 5-Phenylvaleric acid (2.67 g, 15 mmol) in distilled THF was reacted with CDI (15 mmol) followed by glycine ethyl ester·HCl (15 mmol) and (C₂H₅)₃N (15 mmol) as described in Example 32 Part A. The crude material (3.25 g, 82%) was used without purification. B. 5-Phenylpentanoyl glycine The Part A ester (12.34 mmol) was hydrolyzed with NaOH in water as described in Example 32 Part B. The crude product was recrystallized from EtOAc (12 ml) to give title compound (2.39 g, 82%), m.p. 93-96°C. C. [1S-[1α,2β(5Z),3β,4α]]-7-[3-[[[[(1-Oxa-5-phenylpentyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part B compound (1 mmol) was reacted with CDI (1 mmol) and then with Example 1 Part C chiral amine (1mmol) as described in Preparation 1 Part B. The crude product was chromatographed on silica gel (25 g, Baker for flash chromatography) eluting with 2% MeOH in EtOAc to give title compound (363 mg, 75%) as an oil. TLC: silica gel, 2% MeOH in EtOAc, vanillin R f = 0.33. D. [1S-[1α,2β(5Z),3β,4α]]-7-[3-[[[[(1-Oxa-5-phenylpentyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Part C methyl ester (362 mg, 0.749 mmol) was hydrolyzed with LiOH in a water-THF mixture as described in Preparation 2. The crude crystalline product was recrystallized from EtOAc (10 ml) containing a few drops of MeOH to give title compound (278 mg, 79%), m.p. 129-131°C. TLC: silica gel, 8% MeOH in CH₂Cl₂, vanillin, R f = 0.31 [α] D = -5.5 (c=0.9, CH₃OH) Anal Calcd for C₂₇H₃₈O₅N₂: C, 68.91; H, 8.14; N, 5.95 Found: C, 68.82; H, 8.02; N, 5.88 Example 38 [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[(4-Cyclohexyl-1-oxobutyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid A. 4-Cyclohexylbutanoic acid 4-Phenylbutanoic acid prepared as described in Example 32, Part A was dissolved in glacial acetic acid (25 ml). Platinum oxide (0.1 g) was added and the solution was hydrogenated in the Paar shaker at up to 55 p.s.i. until hydrogen uptake ceased (6.5 hours). The catalyst was removed by filtration and the acetic acid was removed in vacuo . The product crystallized and was recrystallized from Et₂O (20 ml) to give title compound (1.18 g, 77%), m.p. 85-88°C. B. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[(4-Cyclohexyl-1-oxobutyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester The Part A acid (341 mg, 1.5 mmol) was dissolved in CHCl₃ (10 ml) in an argon atmosphere. The solution was cooled in an ice bath and carbonyldiimidazole (2.43 mg, 1.5 mmol) was added. The mixture was stirred cold 30 minutes and at room temperature 1 hour. The hydrochloride of the chiral amine (prepared as described in Example 1 Part C) (456 mg, 1.5 mmol) was added. The solution was cooled in an ice bath and tri-n-butylamine (0.36 ml, 278 mg, 1.5 mmol) was added and the mixture was left stirring overnight at room temperature. More CHCl₃ (40 ml) was added and the solution was washed with 1N HCl (20 ml), saturated NaHCO₃ solution (20 ml) and saturated NaCl solution (20 ml). After drying (MgSO₄), the solvent was removed in vacuo . The product was purified by chromatography on silica gel (30 g of Baker for flash chromatography) eluting with 1% MeOH in EtOAc to give the title methyl ester (661 mg, 92.5%) as an oil which slowly became crystalline. TLC: silica gel, 2% MeOH in EtOAc, vanillin, R f = 0.26. C. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[(4-Cyclohexyl-1-oxobutyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Part B methyl ester (661 mg, 1.39 mmol) was hydrolyzed with LiOH as described in Preparation 2. The crude crystalline product was recrystallized from EtOAc (15 ml) and MeOH (1 ml) to give title acid compound (542 mg, 84%), m.p. 141-143°C. [α] D = -6.0° (C=0.96, MeOH) TLC: silica gel, 10% MeOH in CH₂Cl₂, vanillin, R f = 0.51 Anal Calcd for C₂₆H₄₂O₅N₂: C, 67.50; H, 9.15; N, 6.06 Found: C, 67.58; H, 9.24; N, 6.05 Example 39 [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[1-Oxo-3-(phenylthio)propyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid A. 3-(Phenylthio)propanoic acid, methyl ester Thiophenol (440 mg, 4 mmol) and Et₃N (70 µl, 0.5 mmol) were dissolved in CH₂Cl₂ (5 ml). Methyl acrylate (412 mg, 4.8 mmol) was added dropwise. The reaction was exothermic. After stirring at room temperature for 30 minutes, the excess methyl acrylate was removed in vacuo . TLC: silica gel, Et₂O-hexane 1:2, UV R f = 0.58. The crude title ester was used without further purification. B. 3-(Phenylthio)propanoic acid The crude Part A methyl ester (∼4 mmole) was treated with 10 ml 1N NaOH and THF (5 ml). After stirring at room temperature 3 hours, ether (30 ml) was added. The layers were separated and the ether layer was reextracted with 1N NaOH solution (10 ml). The combined aqueous layers were washed with Et₂O (20 ml) and then acidified with concentrated HCl. The product was extracted with CHCl₃ (2 x 30 ml). The chloroform extracts were washed with saturated NaCl solution (2 x 20 ml), dried (MgSO₄) and freed of solvent in vacuo leaving title acid as a white solid (quant.). This was used without further purification. C. 3-(Phenylthio)propanoyl glycine ethyl ester Part B acid (0.740 g, 4.06 mmol) was reacted with carbonyldiimidazole (4.06 mmol) followed by glycine ethyl ester·HCl (4.06 mmol) as described in Example 32 Part A to give the title ester (1.00 g, 92%) as crystalline material. D. 3-(Phenylthio)propanol glycine The Part C ethyl ester (0.96 g, 3.6 mmol) was hydrolyzed with NaOH solution as described in Example 32 Part B to give a white solid which was triturated with Et₂O to give title acid (0.75 g, 87%). E. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[1-Oxo-3-(phenylthio)propyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester The Part D acid (359 mg, 1.5 mmol) was reacted with carbonyldiimidazole (1.5 mmol) followed by the hydrochloride of Example 1 Part C chiral amine by the procedure described in Example 38 Part B. The crude product was chromatographed on silica gel (30 g, Baker for flash chromatography), eluting with 1% MeOH in EtOAc to give the title methyl ester (623 mg, 85%) as an oil. TLC: silica gel, 2% MeOH in EtOAc, UV and vanillin R f = 0.21. F. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[1-Oxo-3-(phenylthio)propyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Part E methyl ester (623 mg, 1.285 mmol) was dissolved in THF (25 ml) and H₂O (2.5 ml) in an argon atmosphere and treated with 1N LiOH solution (2.6 ml). The mixture was stirred at room temperature for 5 hours and then worked up as described in Preparation 2. The crude product was chromatographed on silica gel (20 g, Baker for flash chromatography) eluting with 5% MeOH in CH₂Cl₂ to give an oil (436 mg, 71%) which crystallized on standing. This was recrystallized from EtOAc (10 ml) to give title acid (136.5 mg, 22%), m.p. 95-97°C. TLC: silica gel, 10% MeOH in CH₂Cl₂, R f = 0.50. [α[ D = -5.3° (c=0.88, MeOH) Anal Calcd for C₂₅H₃₄O₅N₂S: C, 63.27; H, 7.22; N, 5.90; S, 6.76 Found: C, 63.41; H, 7.28; N, 5.94; S, 6.63 Example 40 [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[[(Phenylmethyl)thio]acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid A. Chloroacetyl glycine Glycine (1.5 g, 20 mmol) was dissolved in 2N NaOH (25 ml, 50 mmol) and ether (20 ml) was added. Chloroacetyl chloride (2.26 g) dissolved in Et₂O (20 ml) was added dropwise at 0°C. The mixture was stirred at 0° for 30 minutes and at room temperature 1 hour. The layers were separated and the water layer was washed with Et₂O (2 x 20 ml). The water layer was then acidified to pH 2 with concentrated HCl and the product was extracted into EtOAc (3 x 50 ml). The combined EtOAc extracts were washed with brine, dried (MgSO₄), and freed of solvent in vacuo to give title acid compound as a solid (2.56 g, 84%) which was used without further purification. B. (Benzylthio)acetyl glycine Part A acid (1.28 g, 8.4 mmol) was dissolved in methanol (10 ml) and cooled in an ice bath. Sodium methoxide (1.08 g, 20 mmol) was added followed by dropwise addition of benzyl mercaptan (1.25 g, 10.08 mmoles). After stirring overnight at room temperature, 1N NaOH solution (10 ml) was added. Ether washes (2 x 40 ml) removed neutral material. The aqueous layer was then acidified to pH 2 with concentrated HCl. The product was extracted with Et₂O (3 x 50 ml), washed with brine, dried (MgSO₄) and freed of solvent in vacuo leaving a white solid. This was recrystallized from benzene to give title acid compound (1.28 g, 64%). C. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[[(Phenylmethyl)thio]acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part B acid (359 mg, 1.5 mmol) was reacted with carbonyldiimidazole (1.5 mmol) followed by Example 1 Part C chiral amine·HCl 3 (1.5 mmol) using the Procedure describea in Example 38. The crude product was chromatographed on silica gel (30 g, Baker for flash chromatography) eluting with 1% MeOH in EtOAc to give title ester as an oil (625 mg, 85%). TLC: silica gel 2% MeOH in EtOAc, UV + vanillin, R f = 0.30. D. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[[(Phenylmethyl)thio]acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Part C methyl ester (625 mg, 1.28 mmol) was hydrolyzed with 1N LiOH solution (2.6 ml) in a THF-water mixture as described in Preparation 1 Part B. The reaction mixture was worked up at 5 hours 20 minutes. The crude product was recrystallized from EtOAc (15 ml) to give title product (427 mg, 77.7%), m.p. 98-101°C. [a] D = -5.7° (c=0.95, MeOH) TLC: silica gel, 10% MeOH in CH₂Cl₂, UV + vanillin, R f = 0.4. Anal Calcd for C₂₅H₃₄O₅N₂S: C, 63.27; H, 7.22; N, 5.90; S, 6.76 Found: C, 63.53; H, 7.42; N, 5.91; S, 6.77 Example 41 [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Butylthio)acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid A. (Butanethio)acetyl glycine Example 40 Part A acid compound (1.28 g, 8.4 mmol) was reacted with 1-butanethiol using the procedure described in Example 40. The crude product was crystallized with diisopropylether (∼10 ml) to give title acid (0.55 g, 32%). B. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Butylthio)acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part A acid (308 mg, 1.5 mmol) was reacted with carbonyldiimidazole (1.5 mmol) followed by Example 1 Part C chiral amine hydrochloride (1.5 mmol) using the procedure described in Example 38. The crude product was chromatographed on silica gel (30 g, Baker for flash chromatography) eluting with 1% MeOH in EtOAc to give title compound (538 mg, 79%) as an oil. TLC: silica gel, 2% MeOH in EtOAc, UV + vanillin, R f = 0.29. C. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Butylthio)acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Part B methyl ester (538 mg, 1.18 mmol) was hydrolyzed with 1N LiOH solution (2.4 ml) in a tetrahydrofuran-water mixture using the procedure described in Preparation 1 Part B. The reaction mixture was worked up in 5 hours. The crude product was crystallized from EtOAC (20 ml) to give title product (444 mg, 85.4%), m.p. 114-116°. [α] D = -6.0° (c=0.9, MeOH) TLC: silica gel, 10% MeOH in CH₂Cl₂, UV + vanillin, R f = 0.3. Anal calcd for C₂₂H₃₆O₅N₂S: C, 59.97; H, 8.24; N, 6.36; S, 7.28 Found: C, 59.77; H, 8.31; N, 6.30; S, 7.27 Example 42 [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[[(Cyclohexylmethyl)thio]acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid A. Cyclohexylmethylthiol acetate Cyclohexylmethyl mesylate (1.92 g, 10 mol) and KSCOCH₃ (1.25 g) were suspended in distilled tetrahydrofuran (THF). The reaction mixture was heated under reflux for 3 hours. Additional KSCOCH₃ (1.25 g) and THF (9 ml) were added and the mixture was heated under reflux an additional 3 hours. Et₂O (100 ml) was added and the mixture was washed with brine (30 ml). The aqueous layer was reextracted with Et₂O (30 ml). The combined organic layers were washed with brine (15 ml), dried (MgSO₄) and freed of solvent to give a straw colored oil (1.8 g). This was chromatographed on silica gel (50 g, Baker for flash chromatography) eluting with 2% Et₂O in hexane to give title compound (1.189 g, 69%) as an oil. TLC: silica gel, 10% Et₂O in hexane, UV and I₂, R f = 0.48. B. [(Cyclohexylmethyl)thio]acetyl glycine Part A compound (6 mmol) and the Example 40 Part A acid (6 mmol) were reacted in the presence of NaOMe (17 mmol) as described in Example 40 Part B. The crude product was crystallized from diisopropyl ether to give title compound (516 mg, 35%). C. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[[(Cyclohexylmethyl)thio]acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid, methyl ester Part B compound (368 mg, 1.5 mmol) was coupled with Example 1 Part C chiral amine·HCl (456 mg, 1.5 mmol) in the presence of carbonyl diimidazole (CDI) (1.5 mmol) as described in Example 38 Part B. The crude product was chromatographed on silica gel (30 g, Baker for flash chromatography) eluting with 1% MeOH in EtOAc to give title compound (542 mg, 73%) as an oil. TLC: silica gel, 2% MeOH in EtOAc, UV + vanillin, R f = 0.38. D. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[[(Cyclohexylmethyl)thio]acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid The Part C methyl ester (542 mg, 1.09 mmol) was hydrolyzed with 1N LiOH (4 ml) in a mixture of THF and water as described in Preparation 2. The crude product was recrystallized from EtOAc (30 ml) to give title acid (439 mg, 83%), m.p. 131-133°C. TLC: silica gel, 10% MeOH in CH₂Cl₂, UV + vanillin, R f = 0.56. [α] D = -5.0° (c=0.95, MeOH). Anal Calcd for C₂₅H₄₀N₂O₅S: C, 62.47; H, 8.39; N, 5.83; S, 6.67 Found: C, 62.37; H, 8.46; N, 5.77; S, 6.60 Example 43 [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Phenylsulfinyl)acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid Powdered NaIO₄ (385 mg, 1.8 mmol) was dissolved in water (12 ml). A solution of Example 33 acid compound (276 mg, 0.6 mmol) in methanol (20 ml) was added. The mixture was stirred overnight at room temperature. Most of the methanol was removed in vacuo . Saturated NaCl solution (50 ml) was added. The product was extracted with CHCl₃ (3 x 50 ml). The combined chloroform extracts were washed with NaCl solution (20 ml), dried (MgSO₄), and freed of solvent in vacuo leaving an oil. This was chromatographed on silica gel (4 g, Baker for flash chromatography) eluting with 5% MeOH in CH₂Cl₂ to give a foam (254 mg) which gave very broad peaks in ¹H NMR. The material was dissolved in CHCl₃ (100 ml) and washed with 1N HCl solution (2 x 25 ml) and saturated NaCl solution (2 x 20 ml), dried (MgSO₄) and freed of solvent in vacuo leaving title acid (213 mg, 74%) as a white solid foam. TLC: silica gel, 10% MeOH in CH₂Cl₂, UV + vanillin, R f =0.14. Anal calcd for C₂₄H₃₂N₂O₆S·0.2 H₂O: C, 60.02; H, 6.80; N, 5.83; S, 6.68 Found: C, 59.95; H, 6.83; N, 5.78; S, 6.53 [α] D = -9.7° (c=0.7, MeOH) Example 44 [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Phenylsulfonyl)acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid Example 33 acid compound (44.5 mg, 0.9 mmol) was dissolved in methanol (10 ml) and cooled in an ice bath. Oxone (810 mg ∼2.7 mmol) dissolved in water (10 ml) was added. The mixture was stirred at room temperature 4 hours, then diluted with water (30 ml). The product was extracted into CHCl₃ (3 x 35 ml). The combined CHCl₃ extracts were washed with saturated NaCl solution (2 x 20 ml), dried (MgSO₄), and freed of solvent in vacuo leaving an oil (430 mg). This was chromatographed on silica gel (10 g, Baker for flash chromatography) eluting with 5% MeOH in CH₂Cl₂ to give title acid, 165 mg (37%). TLC: silica gel, 10% MeOH/CH₂Cl₂, UV + vanillin. R f = 0.27. Anal Calcd for C₂₄H₃₂O₇N₂S·0.5 H₂O: C, 57.46; H. 6.63; N, 5.59 Found: C, 57.27; H, 6.44; N, 5.55 Examples 45 and 46 Following the procedures outlined in the specification and described in the above working Examples, the following compounds may be prepared.

Claims: A compound having the structure including all stereoisomers thereof, wherein n is 1 to 5; R is CO₂H, CO₂X, CO₂ alkali metal, or Z is (CH₂)q where q is 1 to 12 and may be substituted by one or more X or halo groups, and R³ is H, X, C₂₋₁₂ alkenyl, C₂₋₁₂ alkynyl, phenyl, phenyl-X-, X-O-phenyl-OX-, phenoxy, amino, X-amino, phenylamino, phenyl-X-amino, (wherein n' is 0, 1 or 2), X'-amino-X-, phenylamino-X-, phenyl-X'-amino-X-, X'-O-X-, or phenyl-X'OX-, wherein the X and X' groups (as such or as part of another group) are same or different and are alkyl groups which contain 1 to 12 carbon atoms and may include a cycloalkyl substituent which contains 3 to 12 carbon atoms; the phenyl groups (as such or as part of another group) may be substituted with 1 or 2 X groups, and/or 1 or 2 hydroxy groups The compound as defined in Claim 1 wherein R³ is X, -OX or phenylthio-X. The compound as defined in Claim 1 wherein n is 1 to 4. The compound as defined in Claim 1 wherein q is 1. The compound as defined in Claim 1 wherein R is CO₂ - X or CO₂H. The compound as defined in Claim 2 wherein n is 2 to 4, R is CO₂-X or CO₂H, and q is 1. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxohexyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof, including all stereoisomers thereof. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[[(Butylamino)carbonyl]amino]acetyl]amino]methyl]-7-oxabi cyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof, including all stereoisomers thereof. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(Butoxycarbonyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof, including all stereoisomers thereof. [1S-[1β,2α(5Z),3α(R),4β]]-7-[3-[[[1-Oxo-2-[(1-oxohexyl)amino]propyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof, including all stereoisomers thereof. [1S-[1β,2α(5Z),3α(S),4β]]-7-[3-[[[1-Oxo-2-[(1-oxohexyl)amino]propyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof, including all stereoisomers thereof. [1S-[1β,2α(5Z),3α,4β]]-7-[3-[[[[(1-Oxo-4-phenyl)butyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Phenylthio)acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[3-(4-Hydroxyphenyl)-1-oxopropyl]amino]acetyl]amino]methyl]-7- oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[(Phenoxyacetyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(5Z),3β,4α]]-7-[3-[[[[(1-Oxo-3-phenylpropyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(5Z),3β,4α]]-7-[3-[[[(1-Oxo-5-phenylpentyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[(4-Cyclohexyl-1-oxobutyl)amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[1-Oxo-3-(phenylthio)propyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[[(Phenylmethyl)thio]acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Butylthio)acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[[(Cyclohexylmethyl)thio]acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Phenylsulfinyl)acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. [1S-[1α,2β(Z),3β,4α]]-7-[3-[[[[[(Phenylsulfonyl)acetyl]amino]acetyl]amino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid or C₁₋₁₂ alkylesters thereof including all stereoisomers thereof. A compound having the structure including all stereoisomers thereof, wherein R is CH₂OH or wherein R¹ and R² are the same or different and are H, X, hydroxy, X-O- or phenyl, at least one of R¹ and R² being other than hydroxy and X-O- and n, X, Z and R³ being defined as in claim 1. A composition for inhibiting platelet aggregation and/or bronchoconstriction comprising an effective amount of a compound as defined in Claim 1 or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier therefor. A composition for treating peripheral vascular diseases, comprising an effective amount of a compound as defined in Claim 1 or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier therefor. A compound as defined in any one of Claims 1-24 for use in the treatment of cardiovascular conditions and/or bronchoconstriction. Use of a compound as defined in any one of Claims 1-24 for the manufacture of a medicament for treating cardiovascular conditions. Use of a compound as defined in any one of Claims 1-24 for the manufacture of a medicament for treating bronchoconstriction. Use of a compound as defined in any one of Claims 1-24 for the manufacture of a medicament for treating platelet aggregation.

Inventors: NAKANE MASAMI, REID JOYCE ANN, NAKANE, MASAMI, REID, JOYCE ANN
Applicants: SQUIBB & SONS INC, E.R. SQUIBB & SONS, INC.
Application year: 1986
Main classification: C07D493
IPC codes: A61P9, A61P7, A61P11, A61P43, C07D493, A61K31