Abstract
Bactobolin, (3S, 4R, 4aR, 5R, 6R)-4-(L-alanylamino)-3-(dichloromethyl)-3, 4, 4a, 5, 6, 7-hexahydro-5, 6, 8-trihydroxy-3-methyl-1H-2-oxa-1-naphthalenone, is an antitumor antibiotic produced by Pseudomonas. In the present studies, 14 bactobolin analogs with or without substituents on the amino group attached to the 4 position of the bactobolin nucleus were synthesized and evaluated for activity against mouse leukemia P388. These compounds were given intraperitoneally to mice bearing ascitic leukemia P388. Compounds with the L-seryl group and some L-alanine derivatives on the amino group were found to possess antileukemic activity, but at the dose levels tested, they were neither more effective nor more potent than bactobolin which increased the lifespan of leukemic mice by 110% over the control at an optimal dose of 2.5 mg/kg/day. The other analogs examined were found to be ineffective and nonlethal for mice at doses of 10 mg/kg/day or less. The structure-activity relationships for bactobolin analogs are discussed.