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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
(3E)-11,16-Dioxatricyclo-[15.4.0.0(5,10)]henicosa-1(21),3,5,7,9,17,19-heptaen-2-one
Gnanavelu Ganesh1, Santhanagopalan Purushothaman, Piskala Subburaman Kannan
1Department of Physics, SMK Fomra Institute of Technology, Thaiyur, Chennai 603 103, India.
Abstract:
The title compound, C19H18O3, crystallizes with three mol-ecules (A, B and C) in the asymmetric unit. The carbonyl O atom shows positional disorder over two sites in mol-ecules A and B; the site-occupancy ratios are 0.76 (3):0.24 (3) and 0.86 (3):0.14 (3), respectively. The ethyl-ene fragments in each mol-ecule have an E conformation, while the C-O-C-C torsion angles indicate near planarity. The dihedral angles formed by the aromatic rings are 20.0 (1), 23.7 (1) and 16.1 (1)° for mol-ecules A, B and C, respectively. Intra-molecular C-H⋯O hydrogen bonds occur in each mol-ecule.
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