Triterpenoids from Coluria longifolia

Abstract A new triterpenoid named 19-hydroxy swinhoeic acid, together with four known compounds were isolated from the whole plants of Coluria longifolia Maxim. Their structures were elucidated on the basis of spectroscopic data analysis and comparison with previously reported data. Cytotoxicities of the five compounds against HepG2 cell lines were also evaluated, unfortunately, no obvious activities were observed.


Introduction
Coluria longifolia Maxim, a member of the genus Coluria (Rosaceae), is a plant species unique to China. It is mainly distributed in Qinghai, Xizang and Yunnan provinces. The plants of Rosaceae are rich sources of triterpenoids (Wu et al. 2014), tannins (Feng et al. 1996) and flavonoids (Wang et al. 2009) with various activities, such as antitumor (Bilia et al. 1994), anti-hepatitis (Zhang et al. 2004), anti-HIV (Kashiwada et al. 1998) activity, etc. There are four species of genus Coluria, however, there are no phytochemical studies on genus Coluria to date. during our search for structurally interesting bioactive compounds from C. longifolia, a new ursane triterpenoid named 19-hydroxy swinhoeic acid (1), and four known ones (2-5) (see Figure 1) were isolated from 80% ethanol extract of the whole plants of C. longifolia. Herein, we describe the isolation, structural elucidation of the new compound and cytotoxicities of the five compounds against HepG2 cell lines.

Results and discussion
The 80% ethanol extract of the whole plants of C. longifolia (5.0 kg) was suspended in H 2 o and partitioned with ethyl acetate. The obtained ethyl acetate-soluble fraction was submitted to repeated column chromatography (CC) over silica gel, reversed-phase C-18, sephadex LH-20, and finally purified by preparative silica gel TLC, to yield the new compound (1) and four known ones (2-5).

Plant material
The

Conclusions
In this study, five triterpenoids including a new one with rare reported skeleton were obtained from the whole plants of C. longifolia Maxim. Their structures were elucidated by spectroscopic analysis and comparison with literature data. All isolated compounds were assayed for cytotoxicities against HepG2 cell lines, however, no obvious effects were detected.

Disclosure statement
No potential conflict of interest was reported by the authors.

Funding
This work was supported by the science and Technology Foundation of education department of Jiangxi Province [grant number GJJ150839].