The identification of Marker's ‘α-ketodihydrolanosteryl acetate’ as 3β-acetoxylanost-9(11)-en-7-one

Abstract

In addition to 3β-acetoxylanost-8-en-7-one (5) and 3β-acetoxylanost-8-ene-7,11-dione (6), known products of the reaction, oxidation of 3β-acetoxylanost-8-ene (1) with chromic acid–acetic acid at 80° afforded 3β-acetoxylanost-9(11)-en-7-one (4), apparently identical with Marker's ‘α-ketodihydrolanosteryl acetate’. Oxidation of 3β-acetoxy-8α,9α-epoxylanostane (2) and 3β-acetoxylanosta-7,9(11)-diene (3) under the same conditions yielded the same three products.