tan 420e

TAN 420E is a bacterial metabolite originally isolated from Streptomyces. It scavenges 2,2-diphenyl-1-picrylhydrazyl radicals in a cell-free assay (IC50 = 1.3 μM) and reduces thiobarbituric acid reactive substances (TBARS) in rat liver microsomes by 72% when used at a concentration of 100 μg/ml. TAN 420E is active against B. brevis, B. cereus, M. flavus, and S. aureus (MICs = 50-100 μg/ml). It is cytotoxic to P388 and KB lymphocytic leukemia cells (EC50s = 0.022 and 0.3 μg/ml, respectively).