Title
8,4′-Oxyneolignane glucosides from an aqueous extract of “ban lan gen” (Isatis indigotica root) and their absolute configurations
Author
Lingjie Meng, Qinglan Guo, Yufeng Liu, Jiangong Shi
Year
2017
Journal
Acta Pharmaceutica Sinica B
Abstract
Three pairs of glycosidic 8,4′-oxyneolignane diastereoisomers, named isatioxyneolignosides A−F (1–6), were isolated from an aqueous extract of Isatis indigotica roots. Their structures and absolute configurations were elucidated by comprehensive spectroscopic data analysis and enzyme hydrolysis. The validity of ΔδC8-C7 values to distinguish threo and erythro aryl glycerol units and Cotton effects at 235±5 nm to determine absolute configurations at C-8 in 1–6 and their aglycones(1a–6a) are discussed.
Instrument
J-815
Keywords
Circular dichroism, Absolute configuration, Natural products, Medicinal