D-ring substituted 1,2,3-triazolyl 20-keto pregnenanes as potential anticancer agents: Synthesis and biological evaluation.

A facile synthesis of 21-triazolyl derivatives of pregnenolone and their potential antitumour activity is reported. The scheme involves the transformation of the starting pregnenolone acetate into pregnenolone, conversion of pregnenolone to 21-bromo pregnenolone and finally the one-pot, two-step in situ conversion of the bromo derivative to the 21-triazolyl pregnenolone using the 'click chemistry' approach. These derivatives were screened for their anticancer activity against seven human cancer cell lines. The compounds especially 5a, 5b, 5c, 5e, 5g and 5h exhibited significant anticancer activity with compound 5e as the most active in this study.