Indoxamycins A-F. Cytotoxic Tricycklic Polypropionates from aMarine-Derived Actinomycete

摘要

Six antitumor antibiotics of a new structure class, indoxamycins A-F (1-6), were isolated from asaline culture group of marine-derived actinomyces whose strains showed approximately 96%sequence homology of 16S rDNA with the family streptomycetaceae. The structures of theseindoxamycins, which are unusual polyketides composed of six consecutive chiral centers, wereassigned by combined spectral and chemical methods. In feeding experiments using a stable isotopelabel, indoxamycin A was assembled from propionate units initially forming the aglyconpentamethyl indeno furan. The discovery of these unprecedented compounds from marine-derivedactinomycetes, a low gene homology genus, offers a significant opportunity for drug discovery.