C-2801X, a new cephamycin-type antibiotic II. Isolation and characterization

Two new species of Streptomyces, S. heteromorphus and heteromorphus and S. panayensis, were found to produce a new atibiotic named C-2801X together with cephamycins A and B. The antibiotics were separated from each other by column chromatography on Amberlite XAD-2 and isolated in pure form as mono-sodium salts. C-2801X mono-sodium salt has a molecular formula C25H28N3O12SNa, and exhibits antibacterial activity against Gram-positive and Gram-negative bacteria including those insensitive to cephamycins A and B. From its physicochemical and biological properties, C2801X was considered to be a new cephamycin-type antibiotic.