Structure and reactivity of steroidal quinones

Abstract

The preparation of substituted steroidal A-ring 1,4-quinones by nucleophilic addition results in pronounced regioselectivity at C(2), as confirmed by the X-ray analysis of 2-methoxy-2,5(10)-diene-1,4,17-trione. Conformational analysis (PM3, AM1, MNDO) of the suggested protonated intermediates and the difference in the relative energies of the transition states are considered. The results of cytotoxicity tests of selected quinones are also presented