Pseudoverticin, a novel benzoquinone-derived ansamycin antibiotic obtained as new cell cycle inhibitor from Streptomyces pseudoverticillus YN17707

Pseudoverticin (1), a novel benzoquinone-derived ansamycin antibiotic showing cell cycle inhibitory activity, was isolated from the fermentation broth of Streptomyces pseudoverticillus YN17707 together with the known ansamycin antibiotic geldanamycin (2) through a bioassay-guided separation procedure. The structure of 1 was elucidated by spectroscopic methods, being characterized by an ansa bridge the same as that in 2 and a novel benzoquinone-derived moiety. Pseudoverticin (1) arrested the cell cycle of tsFT210 cells at the G0/G1 phase with the MIC value of 2.5 μM.

Pseudoverticin (1), a novel benzoquinone-derived ansamycin antibiotic showing cell cycle inhibitory activity, was isolated from the fermentation broth of Streptomyces pseudoverticillus YN17707 together with the known ansamycin antibiotic geldanamycin (2) and its structure was elucidated by spectroscopic methods. Pseudoverticin (1) provided a new ansamycin antibiotic possessing a novel benzoquinone-derived moiety, which arrested the cell cycle of mouse tsFT210 cells at the G0/G1 phase.