PROCESS FOR PREPARING PROSTAGLANDIN-F DOWN 2 ALPHA-DERIVATIVES

A process for producing F2 alpha prostaglandin and analogues thereof, in which a lactone diol or the C-15 epimer thereof is reacted with a 1-alkoxybenzyl halide in a solution of an aromatic hydrocarbon in the presence of a tertiary amine, at a temperature of - 20 to 40 DEG C and in a molar ratio of reacting components of 1.0: 1.0 to 1.1. The protected lactone is then reduced with a complex hydride at a temperature of - 80 to 20 DEG C. The lactol or C-15 epimer obtained by this reduction is then reacted with an "ylide" in a polar aprotic solvent to give the bisacetal of prostaglandin or the C-15 epimer thereof. The desired product is obtained using a 0.4 to 2 N oxalic acid solution or after isolation with a cation exchanger, in an aqueous medium with 10 to 80% by weight of an alcohol having 1 to 4 carbon atoms at a temperature of 20 to 80 DEG C. F2 alpha prostaglandin and analogues thereof are biologically active and are used in human and veterinary medicine.