STRUCTURE-ACTIVITY RELATIONSHIP OF PAMAMYCINS - EFFECTS OF ALKYL SUBSTITUENTS

Nine new pamamycin homologues were isolated from the culture broth of Streptomyces alboniger IFO 12738 using a combination of ODS and NH, HP LCs, and their structures determined by CC-MS. The structural differen ces in these homologues are in the numbers and positions of methyl and ethyl groups. The aerial mycelium-inducing and growth-inhibitory acti vities in S. alboniger of these homologues and their antibiotic activi ty against Bacillus subtilis were examined. The effects of the alkyl s ubstituents on these activities are discussed.