Abstract The occurrence of δ22, 25-sterols has been reported in a number of plants. 1–6 From a chemical point of view, it seems that such systems would be ideal for the alkylation of the side chain of cholesterol to give that of ergosterol, sito-sterol and stigmasterol. Furthermore, such dienes would give by hydration ecdysone-like compounds. Sih and Whitlock3 have discussed recently the involvement of a diene intermediate in the ...
