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