3β,6α-Diacet-oxy-5,9α-dihy-droxy-5α-cholest-7-en-11-one.

ABSTRACT: The title compound, C31H48O7, a polyoxygenated steroid, was obtained by chemical oxidation of 7-de-hydro-cholesteryl acetate. The mol-ecular geometry features trans A/B and C/D junctions at the steroid core with the acetyl groups in the equatorial position and a fully extended conformation for the alkyl side chain. A chair conformation is observed for rings A and C while ring B adopts a half-chair conformation. The five-membered ring D has an envelope conformation, with the C atom bearing the methyl group at the flap. The terminal isopropyl group and one acetyl group are disordered over two sets of sites with 0.774 (8):0.226 (8) and 0.843 (7):0.157 (7) ratios, respectively. An intra-molecular S(6) O-H⋯O hydrogen-bonding motif involving a hy-droxy donor and acceptor is observed. In the crystal, chains of mol-ecules running along the b axis are formed via O-H⋯O hydrogen bonds between hy-droxy donors and carbonyl acceptors of the ordered acetyl group, giving rise to a C(14) motif. The chains are wrapped around the 21 screw axes.

SUBMITTER: Piccialli V 

PROVIDER: S-EPMC3770383 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature