5α-Dihydro­vespertilin acetate

Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4.
Acta Crystallographica Section E Structure Reports Online (Impact Factor: 0.35). 03/2010; 66(Pt 3):o598. DOI: 10.1107/S160053681000512X
Source: PubMed

ABSTRACT In the title compound, C(24)H(36)O(4) [systematic name: (20S)-3β-acet-oxy-16α-hydr-oxy-22,23-bis-nor-5α,17β-cholano(22-16)lac-tone], the three six-membered rings adopt classical chair conformations, while the five-membered rings are in envelope conformations. The ester group attached to ring A is in an equatorial position. Rings A/B, B/C and C/D are trans-fused, whereas rings D/E are cis-fused. The structure is devoid of any classical hydrogen bonds. However, non-classical inter- and intra-molecular hydrogen-bonding inter-actions of the type C-H⋯O are present in the structure.

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