REGIOSELECTIVE AND STEREOSELECTIVE REACTIONS OF 17-PHENYL-18,19,20-TRINORPROSTAGLANDIN F2-ALPHA ISOPROPYL ESTER

Novel prostaglandin F-2 alpha derivatives, functionalized at C13 and C 14, have been prepared. 17-Phenyl-18,19,20-trinorprostaglandin F-2 alp ha isopropyl ester [(15S)-1] and its epimer [(15R)-1] were stereoselec tively epoxidized, using Sharpless conditions, to produce each of the four diastereomeric epoxides (15S)-2, (15S)-3, (15R)-2, and (15R)-3. T reatment of the four epoxides with LiOH stereospecifically-produced th e pentahydroxy substituted analogues 12 and 13. Alternatively, epoxide s 2 and 3 were allowed to react with thiophenolate ion. The attack of the sulfur nucleophile on the epoxide occurred at either C13 or C14 de pending on the stereochemistry of the epoxide and of C15.