Two new lignan-iridoid glucoside diesters from the leaves of Vaccinium bracteatum and their relative and absolute configuration determination by DFT NMR and TDDFT-ECD calculation

July 28, 2017

Title

Two new lignan-iridoid glucoside diesters from the leaves of Vaccinium bracteatum and their relative and absolute configuration determination by DFT NMR and TDDFT-ECD calculation

Author

Yong-Mei Ren, Chang-Qiang Ke, Attila Mándi, Tibor Kurtán, Chunping Tang, Sheng Yao, Yang Ye

Year

2017

Journal

Tetrahedron

Abstract

Two new lignan-iridoid glucoside diesters (2 and 3), together with their putative biosynthetic precursor 10-O-trans-caffeoyl-6α-hydroxyl-dihydromonotropein (1), were characterized from the leaves of Vaccinium bracteatum. Their planar structures and relative configuration were elucidated by spectroscopic measurements and DFT C NMR calculations, and their absolute configurations were determined by time-dependent density functional theory (TDDFT) electronic circular dichroism (ECD) calculations. The plausible biosynthetic pathways of new compounds were also proposed.

Instrument

J-810

Keywords

Circular dichroism, Absolute configuration, Natural products, Pharmaceutical