TAN 420C is a hydroquinone ansamycin antibiotic originally isolated from Streptomyces. It exhibits antibacterial activity against B. brevis and M. flavus (MICs = 50 and 25 μg/mL, respectively). Additionally, it inhibits proliferation in the lymphocytic leukemia cell lines P388 and KB (ED50s = 0.34 and 3.49 μg/mL, respectively).
TAN 420C is a minor analogue of the herbimycin complex, isolated from Streptomyces hygroscopicus. TAN 420C is the hydroquinone of herbimycin C, and is known to exhibit antitumour activity. TAN 420C converts Rous sarcoma virus-infected rat kidney cells into normal cells.
