Macrolide antibiotics M-4365 produced by Micromonospora. II. Chemical structures

By physiochemical analyses and chemical procedures, the structures of a series of basic 16-membered macrolide antibiotics, M-4365, A1, A2, A3, G1, G2 and G3 were elucidated, and it was found that M-4365 A1, G1 and G2 were novel, while M-4365 A2, A3 and G3 were identical with rosamicin, juvenimicins A4 and B1, respectively.