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Updated: May 13, 2026

Cellular Lipid Extraction for Targeted Stable Isotope Dilution Liquid Chromatography-Mass Spectrometry Analysis
Published on: November 17, 2011
1β,15α-Dihy-droxy-16α,17-ep-oxy-pregn-4-ene-3,20-dione
Yan-Bing Shen1, Yi-Bo Wang, Jian-Mei Luo
1Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, People's Republic of China.
Abstract:
The title mol-ecule, C21H28O5, is composed of three six-membered rings (A/B/C) and a five-membered ring (D). Ring A adopts a 1α-sofa conformation, while rings B and C adopt chair conformations. Cyclo-pentane ring D adopts a 14α-envelope conformation. In the crystal, O-H⋯O hydrogen bonds lead to the formation of ribbons running along the a axis. The structure is further consolidated by C-H⋯O inter-actions, which link the molecules head-to-tail into ribbons along the a axis.
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