Novel cytocidal compounds, oxopropalines from Streptomyces sp. G324 producing lavendamycin. I. Taxonomy of the producing organism, fermentation, isolation and biological activities.

In the course of our investigation aimed at the discovery of novel antitumor antibiotics from microorganisms, Streptomyces sp. G324 was found to produce the antitumor antibiotic, lavendamycin, and also, to yield the novel beta-carboline compounds, oxopropalines. We isolated five compounds as oxopropalines A, B, D, E and G. Oxopropalines B, D and G showed cytocidal activities against human or murine tumor cell lines in vitro.