22,25-Dideoxyecdysome (1) and 5alpha-22.25-dideoxyecdysone (1a) were prepared from cholesterol via a new scheme using the key intermediates 3beta-chloro-5alpha-bromo-6-ketone 3. 3beta-chloro-7alpha-bromo-6-ketone 4, and 2,7-dien-6-one 7.
SHAFIULLAH;SIDDIQUI, I. H.;AHMAD, S., INDIAN J. CHEM. B, 27,(1988) N 3, C. 279-280