Calciferol and its relatives. Part XV. The preparation of des-AB-cholest-8-ene-8-carbaldehyde {1β-[(1R)-1,5-dimethylhexyl]-3aα,6,7,7aβ-tetrahydro-7aβ-methylindane-4-carbaldehyde} and 9α-chloro-des-AB-cholestan-8-one {5α-chloro-1β-[(1R)-1,5-dimethylhexyl]-7aβ-methyl-trans-perhydroindan-4-one}

Abstract

Several des-AB-cholestane derivatives, carrying oxygen functions at position 8 or 9, or both, are prepared from des-AB-cholest-8-ene or from des-AB-cholestane-8β,9α-diol. They include the two title compounds, required for the total synthesis of tachysterol₃ and precalciferol₃, respectively.