Cairomycin B, a new antibiotic.

Cairomycin B is a new cyclic peptide antibiotic that was isolated from Streptomyces As-C-19 obtained from the soil of Cairo. The antibiotic had the following empirical formula: C(10)H(15)N(3)O(3); on acid hydrolysis, it yielded aspartic acid and lysine. Spectral analysis and its chemical characteristics indicated that it was a cyclic peptide.