Patent GB-1384900-A (GB)
Title: Cyclopentaneheptanoic acid derivatives
IPC: C07D317/72
Filed: 1972-11-20
Abstract: 1384900 Cyclopentaneheptanoic acid derivatives MERCK & CO Inc 20 Nov 1972 [24 Nov 1971] 53438/72 Heading C2C The invention comprises C 1-6  alkyl and aralkyl esters of 3#-hydroxy-2α-(3(s)-hydroxy-trans-1- octenyl)-5-oxo-1#-cyclopentaneheptanoic acid 5-cyclic ethylene acetal (9) and stereoisomers thereof, 3#-hydroxy-2α-(3-oxo-trans-1-octenyl). 5-oxo-1#-cyclopentane-heptanoic acid 5-cyclic ethylene acetal (8), the C 1-6  alkyl and aralkyl esters thereof and stereoisomers thereof, 3#- [(methoxalyl)oxy]-2α-(3-oxo-trans-1-octenyl)-5- oxo-1#-cyclopentaneheptanoic acid (7A), the C 1-6  alkyl and aralkyl esters thereof, and stereoisomers thereof, and 2α-formyl-3#-[(methoxalyl)oxy]-5-oxo-1#-cyclopentaneheptanoic acid (7), the C 1-6  alkyl and aralkyl esters thereof and stereoisomers thereof, their preparation and the preparation of the cyclic ethylene acetal of prostaglandin E 1  by treating the esters of the first named compound (9) with alkali metal hydroxides in aqueous solutions. The compounds (9) and the corresponding free acid are prepared by reducing compounds (8), obtained by reacting alkylene 1,2-diamines with compounds (7A) which are obtained by reacting alkali metal hydride and dimethyl 2-oxoheptylphosphonate with compounds (7), resulting from the reaction of osmium tetraoxide in the presence of alkali metal periodate and methanol on 2α - (2 - acetoxy - 2 - carboxyvinyl) - 3# - hydroxy-5-oxo-1#-cyclopentaneheptanoic acid 8- lactone 5-cyclic ethylene acetal or the C 1-6  alkyl or aralkyl esters thereof. The following intermediates and starting materials are also prepared: 3α - Methyl - 4 - cyclohexene - 1α,2α - dimethanol, and the di-p-toluenesulphonate thereof, 3α - methyl - 4 - cyclohexene - 1α,2α - diacetonitrile, 3α-methyl-4-cyclohexene-1α,2α-diacetic acid, 4α-hydroxy-5#-iodo-3α-methyl-1α,2α-cyclohexanediacetic acid 6-lactone, and the methyl esterthereof, 4α-hydroxy-3α-methyl-1α,2α-cyclohexanediacetic acid 8-lactone, dehydroabietylamine salt thereof and the methyl ester thereof, 4α-hydroxy-3α-methyl-1α,2α-cyclohexanediacetic acid, the dimethyl ester thereof and methane sulphonate of the said dimethyl ester, 3-methyl- 3-cyclohexene-1α,2α-diacetic acid and the dimethyl ester thereof, 3a,6,7,7a-tetrahydro-1α- methoxycarbonyl - 4 methyl - 2 - oxo - 1#- indane-heptanoic acid methyl ester, 3a,6,7,7atetrahydro-4-methyl-2-oxo-1#-indaneheptanoic acid methyl ester and 2-cyclic ethylene acetal thereof, 3α-methyl-4-cyclohexene-1α,2α-dicarboxylic acid 1-methyl ester and its salt with dehydroabietylamine, 3-acetyl-2α-(2-carboxyethyl)-5-oxo-1#-cyclopentaneheptanoic acid methyl ester 5-cyclic ethylene acetal, 3#-acetyl 2α - (2 - methoxycarbonylethyl) - 5 - oxo - 1#- cyolopentaneheptanoic acid methyl ester 5- cyclic ethylene acetal, 3#-acetoxy-2α-(2-methoxy - carbonylethyl) - 5 - ozo - 1# - cyclopentaneheptanoic acid methyl ester 5-oyclic ethylene acetal, 2α-(2-methoxycarbonylethyl)-3#- hydroxy-5-oxo-1#-cyclopentane-heptanoic acid methyl ester 5-cyclic ethylene acetal, 2α-(2- carboxyethyl) - 3# - hydroxy - 5 - oxo - 1#- cyclopentaneheptanoic acid methyl ester 8- lactone 5-cyclic ethylene acetal, 2α-(2-carboxy- 2 - formylethyl) - 3# - hydroxy - 5 - oxo - 1#- cyclopentaneheptanoic acid methyl ester 8- lactone 5-cyclic ethylene acetal, 2α-(2-carboxy- 2-oxoethyl)-3#-hydroxy-5-oxo-1#-cyclopentaneheptanoic acid methyl ester 8-lactone 5-cyclic ethylene acetal, and 2α-(2-acetoxy-2-carboxyvinyl)-3#-hydroxy-5- oxo-1#-cyclopentane-heptanoic acid methyl ester #-lactone-5-cyclic ethylene acetal.