Chloropolysporins A, B and C, novel glycopeptide antibiotics from Faenia interjecta sp. nov. III. Structure elucidation of chloropolysporins

Structure elucidations of chloropolysporins A, B and C were achieved mainly by chemical degradation studies. These components possessed the same pseudoaglycone in common and their structures were closely related to that of beta-avoparcin. The structures of chloropolysporins differ from that of beta-avoparcin in the presence of vancomycinic acid moiety instead of monodechlorovancomycinic acid moiety and glucose, not ristosaminylglucose, in its side chain. Chloropolysporin C was identified as derhamnosylchloropolysporin B based on its 1H NMR and mass spectral analysis and degradation studies. Two minor components, chloropolysporins D and E, were identified as the epimers of each of chloropolysporins B and C, respectively, based on their Cotton effects and retention times on reverse phase HPLC.