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Updated: May 27, 2026

Cellular Lipid Extraction for Targeted Stable Isotope Dilution Liquid Chromatography-Mass Spectrometry Analysis
Published on: November 17, 2011
21-Hy-droxy-pregna-1,4-diene-3,20-dione
S Yousuf1, M Bibi, M I Choudhary
1H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan.
Abstract:
The title compound, C(21)H(28)O(3), is a fungal transformed metabolite of decoxycorticosterone acetate, consisting of four fused rings A, B, C and D. Ring A is nearly planar, with a maximum deviation of 0.010 (3) Å from the least-squares plane, while the trans-fused rings B and C adopt chair conformations. The five-membered ring D is in an envelope conformation. The orientation of the side chain is stabilized by an intramolecular O-H⋯O hydrogen bond. In the crystal, adjecent mol-ecules are linked by C-H⋯O hydrogen bonds into extended zigzag chains along the a axis.
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