A STRUCTURALLY AND BIOGENETICALLY INTERESTING MOENOMYCIN ANTIBIOTIC

Isolation and structure elucidation of a new moenomycin antibiotic (A( 12), 1a) is reported that differs from moenomycin A by lack of the bra nching methyl group and by the configuration at C-4 of unit F. The sma llest antibiotically active degradation product of 1a is the trisaccha ride derivative 3a. This observation is in contrast to structure activ ity relations in the moenomycin A series where it was found that disac charide 4b is fully active. An explanation is offered for this differe nce.