Roxburghiadiol A and Roxburghiadiol B, Two 14α-Methylsterols from Aglaia roxburghiana

Abstract
Two new 14.alpha.-methylsterols, roxburghiadiol A and roxburghiadiol B, were isolated from the leaves and fruits of Aglaia roxburghiana. Previously their structures were tentatively assigned as 4-bisnormethyl-24-methylene-cycloarta-3.beta.,7.alpha.-diol and 4-bisnormethyl-24-methylene-cycloarta-3.beta.,6.alpha.-diol,respectively. A reinvestigation using 2D-nmr technique has confirmed the structure 2 for roxburghiadiol B as previously reported, and roxburghiadiol A is now found to be the corresponding 6.beta. epimer 1.