A Tri-O-Bridged Diels-Alder Adduct from Cortex Mori Radicis

May 22, 2018

Title

A Tri-O-Bridged Diels-Alder Adduct from Cortex Mori Radicis

Author

An-Qi Lu, Ming-Hua Chen, Jie Gao, Lu Wang, Han-Yu Yang, Lan Li, Bo Zhang, Hao-Ke He, Su-Juan Wang

Year

2018

Journal

Molecules

Abstract

Sanggenon X, an unusual tri-O-bridged Diels-Alder adduct, was isolated from Cortex Mori Radicis. Its structure was established by spectroscopic analysis, including NMR and HR-MS (High Resolution Mass Spectrometry). Sanggenon X contained three O-bridged rings, where the oxygenated bridgeheads were all quaternary carbons. Chemical methylation was carried out to deduce the linkages of the three O-bridges. The absolute configuration was determined by calculating the ECD (Electronic Circular Dichroism) using the TDDFT (Time-Dependent Density Functional Theory) method. Sanggenon X showed significant antioxidant activity against Fe2+-Cys-induced lipid peroxidation in rat liver microsomes, and was as effective as the positive control, curcumin.

Instrument

J-815

Keywords

Circular dichroism, Absolute configuration, Natural products, Medicinal