Crystal structure of an ep-oxy-sterol: 9α,11α-ep-oxy-5α-cholest-7-ene-3β,5,6α-triol 3,6-di-acetate
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Updated: Feb 18, 2026

Enzymatic Synthesis of Epoxidized Metabolites of Docosahexaenoic, Eicosapentaenoic, and Arachidonic Acids
Published on: June 28, 2019
Vincenzo Piccialli1, Angela Tuzi1, Roberto Centore1
1Dipartimento di Scienze Chimiche, Università degli Studi di Napoli 'Federico II', Complesso di Monte S. Angelo, Via Cinthia, 80126 Napoli, Italy.
Abstract:
The title compound, C31H48O6, is a polyoxygenated ep-oxy steroid obtained by a multi-step synthesis involving oxidation of 7-de-hydro-cholesterol. It crystallizes in the P212121 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).
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