AUTHOR=Wang Huijuan , Ma Guoxu , Wang Huaxiang , Li Lingyu , Dong Aijun , Liu Huiping , Huo Xiaoshuang , Si Jianyong , Wang Junchi 

TITLE=Novel Triterpenoid Alkaloids With Their Potential Cytotoxic Activity From the Roots of Siraitia grosvenorii

JOURNAL=Frontiers in Chemistry

VOLUME=Volume 10 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2022.885487

DOI=10.3389/fchem.2022.885487

ISSN=2296-2646

ABSTRACT=Four novel triterpenoid alkaloids, siragrosvenins A-D (1-4) and two new cucurbitane-type triterpenoids, siragrosvenins E-F (5, 6), together with eight known analogues (7−14), were isolated from the roots of Siraitia grosvenorii. Compounds 1-4 possessed a rare cucurbitane-type triterpenoid scaffold, featuring an extra pyrazine unit via strecker reaction in the cucurbitane framework. Compound 5 displayed a 6/6/6/5/6/5-fused polycyclic ring system, with an uncommon fused furan and pyran rings in the side chain. All the structures were characterized by extensive spectroscopic analysis, including HRESIMS, NMR, and X-ray crystallographic data. It's worth noting that DP4+ analysis method was applied for the first time to determine the absolute configurations of the trihydroxybutyl moiety in the side chain of compounds 1-4. Cytotoxicity screening in vitro found that compounds 4, 8, 9, 13, 14 exhibited remarkable cytotoxic activities against three cell lines with IC50 values ranging from 1.44 to 9.99 μM. Siragrosvenin D, showing a remarkable cytotoxic activity on MCF-7 cells. As results, it inhibited proliferation of MCF-7 cells and reduces their viability via the induction of G2/M phase arrest, and significantly induced apoptosis in MCF-7 cells.