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Updated: Aug 5, 2026

Real-time Monitoring of Reactions Performed Using Continuous-flow Processing: The Preparation of 3-Acetylcoumarin as an Example
Published on: November 18, 2015
Absolute configuration determination of angular dihydrocoumarins from Peucedanum praeruptorum
Hong-Xiang Lou1, Long-Ru Sun, Wen-Tao Yu
1Department of Natural Medicinal Chemistry, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China. louhongxiang@sdu.edu.cn
Abstract:
From Peucedanum praeruptorum, one new khellactone ester (3'R)-O-acetyl-(4'S)-O-angeloylkhellactone (3), as well as four known angular dihydropyranocoumarins (1, 2, 4, 5) have been isolated. On the basis of NMR spectra and X-ray crystallography, their structures were determined. We have elucidated their absolute configuration by either chiral separation of their alkaline hydrolysis products with Rp-18 HPLC eluted with 5% hydroxypropyl-beta-cyclodextrin (beta-HCD) or by measurement of their CD spectra. A general rule relating the position and absolute streochemistry of the khellactone esters to the sign of their Cotton effects in CD curves is proposed.
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