Deepoxidation of 16-membered epoxyenone macrolide antibiotics. II. Chemical deepoxidation by dissolving metal reduction.

16-Membered epoxyenone macrolide antibiotics were reductively deepoxidized with dissolving metals such as zinc. Angolamycin and rosamicin which have a methyl substituent at C-12 in the epoxyenone structure were deepoxidized, but not isomerized further to the geometric isomers P2 and P3.