process for the production of 55 forms of 4 - trinor - 1.5 - inter - m - phenylen - prostacyclinderivaten

摘要

The invention relates to the preparation of 5Z forms of 2,3,4-trinor-1,5-inter-m-phenylene prostacyclin derivatives of the formula IMAGE in which R1 is a hydrogen atom, a cation or a lower alkyl radical, R2 is a hydrogen atom or a methyl radical, A is one of the groups -CH2-CH2-, (trans)-CH=CH- or -C IDENTICAL C- and B is an alkyl radical or a cycloalkyl radical which is optionally substituted by a lower alkyl radical, by isomerisation of a compound of the formula IMAGE in which R2, A and B have the above meaning and R'1 represents a lower alkyl radical or an aralkyl radical, and, if desired, subsequent conversion of R'1 to R1. This isomerisation is effected by treating the compound of the formula IIE in the presence of an anhydrous solvent with at least one salt composed of an organic base and an organic sulphonic acid or a fluorinated or chlorinated acetic acid.