Nonbiological conversion of cephalosporin C to a new antibiotic by sodium thiosulfate.

The apparent stimulation of cephalosporin C biosynthesis by sodium thiosulfate is due to a nonbiological conversion of cephalosporin C to a new derivative, cephalosporin C(x). The new compound is more active than cephalosporin C against the assay organism, Escherichia coli W-208. Cephalosporin C(x) retains the properties of ultraviolet absorption and resistance to penicillinase, but migrates more slowly than cephalosporin C in the paper-chromatographic system used.