The structure of afragilimycin A.

cin A (1) with a salt of streptolydigin. In our search for antibiotic substances from microorganisms, we isolated afragilimycin A from a Streptomyces sp. Afragilimycin A, described by Arai1}, does inhibit the growth of both Grampositive and Gram-negative bacteria, and has intermediate toxicity. Though several physical characteristics of the compoundsuch as IR, UVand 1VL NMR spectra are known, the structure of afragilimycin A has not been elucidated. Arai has Fig. 1. Structure of afragilimycin A (1), streptolydigin (2) and afragilimycin diacetate (3).