Crystal structure of an ep-oxy-sterol: 9α,11α-ep-oxy-5α-cholest-7-ene-3β,5,6α-triol 3,6-di-acetate.

The title compound, C(31)H(48)O(6), is a polyoxygenated ep-oxy steroid obtained by a multi-step synthesis involving oxidation of 7-de-hydro-cholesterol. It crystallizes in the P2(1)2(1)2(1) space group; however, the absolute structure of the molecule in the crystal could not be determined by resonant scattering. The configuration at the C5 and C6 positions is in both cases of the α-type, as is that of the C atoms of the ep-oxy ring. Mol-ecules in the crystal form chains parallel to the b axis by hydrogen bonding between O-H donors and carbonyl O-atom acceptors. Some atoms of the alkyl chain are disordered over two orientations, with a refined occupancy ratio of 0.511†(10):0.489†(10).