Trigonostemons G and H, dinorditerpenoid dimers with axially chiral biaryl linkage from Trigonostemon chinensis.

Abstract:

:Trigonostemons G and H, two novel dimeric dinorditerpenoids, were isolated from the stem barks of Trigonostemon chinensis. Their planar structures and relative configurations were established by extensive analysis of spectroscopic data. Trigonostemons G and H possess a homodimeric biaryl skeleton obtained from two rearranged chiral nonracemic abietane-type dinorditerpenes through an axially chiral biaryl 11,11'-linkage. Torsional scan and computation of the transition states were carried out to estimate the rotational energy barrier, and the axial chirality (aS) was determined by time-dependent density functional theory (TDDFT) electronic circular dichroism (ECD) calculations. The positive n-π* ECD transitions of the isolated carbonyl chromophore above 300 nm could be used to determine the central chirality of trigonostemon G independently by ECD calculations of the diastereomers.

journal_name

Chirality

journal_title

Chirality

authors

Zhu Q,Tang C,Mándi A,Kurtán T,Ye Y

doi

10.1002/chir.23170

subject

Has Abstract

pub_date

2020-03-01 00:00:00

pages

265-272

issue

3

eissn

0899-0042

issn

1520-636X

journal_volume

32

pub_type

杂志文章