Isolation and structure determination of crisamicin A, a new antibiotic from Micromonospora purpureochromogenes...

A new antibiotic, crisamicin A, with in vitro activity against Gram-positive bacteria, B16 murine melanoma cells, and herpes simplex, vaccinia, and vesicular stomatitis viruses, has been isolated from Micromonospora purpureochromogenes subsp. halotolerans. On the basis of 1H and 13C NMR spectroscopic, high resolution field desorption mass spectrometric, and circular dichroism studies of the antibiotic and several of its derivatives, the structure of crisamicin A has been assigned.