Abstract
Ozonolysis of 3β-acetoxycholest-5-en-7-one (Ia), 3β-acetoxyandrost-5-en-7, 17-dione (Ib), and 3β-acetoxypregn-5-en-7, 20-dione (Ic) afforded 3β-acetoxy-5-formoxy-6-oxa-5ξ-cholestan-7-one (IIIa), 3β-acetoxy-5-formoxy-6-oxa-5ξ-androstan-7, 17-dione (IIIb), and 3β-acetoxy-5-formoxy-6-oxa-5ξ-pregnan-7, 20-dione (IIIc), respectively. The corresponding δ-keto acids (IIa, b, c) were also isolated from the reaction mixture. Some 6-oxa-and 6-aza-steroids were derived from the δ-keto acid II as well as from its pseudo acid formate III and acetate IV.
