Diosgenin-3,6-dione: second polymorph in space group 222.

The title steroid, [(25)-spirost-4-en-3,6-dione, CHO], is obtained by oxidation of diosgenin, using the Jones reagent (CrO/HSO). The crystal structure was previously reported in space group 222, but nonetheless with the wrong absolute configuration and omitting positions for H atoms [Rajnikant (2000 ▸). , , 101-110].