A long-range intramolecular functionalization by alkoxyl radicals: a long-range intramolecular hydroxylation of C(25) of cholestane side chain

Abstract

Alkoxyl radicals generated by the irradiation of hypoiodites of 5α-chlolestan-7α-yl-4-(hydroxyphenylmethyl)-phenylacetates and 5α-cholestan-7α-yl-3-[4-(hydroxyphenylmethyl)phenyl] propionates, respectively, abstracted a hydrogen from the remote C(25) of their cholestane side chain to give novel macrocyclic ether lactones which gave 5α-cholestane-7α, 25-diol by reduction with Na and liquid ammonia in good yields.