4’-Acetylchrysomycin B and its co-metabolite, 4’-acetylchrysomycin A, were isolated during a screen for antitumor agents. Acetylation of chyrsomycin B increase cytotoxicity. Acetylchyrsomycins are active against Gram-positive bacteria, including MRSA and VRE, with MICs of 0.5-2 μg ml-1 to >64 μg ml-1 for 4'-acetylchrysomycin A and B, respectively.
