Rational design, synthesis, and in vivo evaluation of the antileukemic activity of six new alkylating steroidal esters

The synthesis and the in vivo evaluation against leukemias P388 and L1210 of six new alkylating steroidal esters are described. The esteric derivatives incorporating the 17β-acetamido-B-lactamic steroidal skeleton exhibited increased antileukemic activity and lower toxicity, compared to the 17β-acetamido-7-keto analogs. Among the 17β-acetamido-B-lactamic steroidal esters, the most potent compound afforded four out of six cures in leukemia P388 and was measured to be almost non-toxic, producing significant low levels of toxicity.