Synthesis of Cholest-5-en-24-oxo-3b, 19-Diacetate

Two biologically active 19-hydroxylated sterols, 24-methylenecholesta-3b, 5a, 6b, 19- tetrol 1, 24-methylenecholesta-5-ene-3b, 7b, 19-triol 2, were isolated from the soft corals, Nephthea albida and Nepthea tiexieral verseveldt by L. M. Zeng1,2. 1 showed strong anti-inflamatory activity comparable with dexamethone and 2 showed potent anti-leukemic activity (IC50 0.01 mg/mL). We have designed a synthetic route for the synthesis of 1 and 2 as shown in Scheme 1. In this route, cholest-5-en-…