Aromatic steroids. Part I. Oxidation products of 3-methoxyoestra-1,3,5(10)-trien-17β-yl acetate

Abstract

Re-examination of chromium trioxide oxidations of 3-methoxyoestra-1,3,5-(10)-trien-17β-yl acetate (1; R¹= OAc, ⋯ H, R²= H₂) has shown that the neutral products are a ketol (IV; R¹= OAc, ⋯ H, R²= Me, R³= OH, R⁴= H₂), a 6-oxo-derivative (I; R¹= OAc, ⋯ H, R²= O), a hydroxy-dione (IV; R¹= O, R²= Me, R³= OH, R⁴= H₂), and a mixture of a hydroxy-dione (IV; R¹= OAc, ⋯ H, R²= Me, R³= OH, R⁴= O) and a hydroxy-trione (IV; R¹= R⁴= O, R²= Me, R³= OH). Evidence is presented that the 9-hydroxy-group of the ketol has a β-configuration rather than the α-configuration previously assigned. Acids from the oxidation include C-seco-acids (III; R = OAc, ⋯ H) and (III; R = O), and structures (VII) and (VIII) for lactones derived from the latter acid have been proposed.