Total synthesis of prostaglandin-F2α, and the 9-O-benzyl derivatives of prostaglandins-F2α, -F1α, -D2, and -D1

Abstract

As an extension of the method whereby prostaglandin-F₂α may be prepared by homoconjugate addition of an organocuprate reagent to the 3-endo-silyloxytricyclo[3.2.0.0.^2,7]heptan-6-one (3), 3-endo-benzyloxytricyclo-[3.2.0.0^2,7]heptan-6-one (4) has been used to give the prostaglandin intermediate (14), in which the three hydroxy-functions at C-9, C-11, and C-15 are fully differentiated. Unmasking of the C-9 hydroxy-group gives the 15-silylated PG–F₂α(15). The novel 9-O-benzyl derivatives of prostaglandin 5-F₂α, -F₁α, -D₂, and -D₁ were also prepared from (14) as possible antagonists of the natural compounds.