A new phenylpropanoid-substituted epicatechin from the rhizome of Smilax china

Abstract

A new phenylpropanoid-substituted epicatechin, (2 R,3S,9R)-methyl {2-(3,4-dihydroxyphenyl)-3,5,8a,4a-tetrahydroxy-3,4-dihydro-2H,12H-pyrano[2,3-α]xanthen-12-yl}acetate (1) was isolated from the rhizome of Smilax china, along with twelve known compounds (2 − 13), which were isolated from the Smilax genus for the first time. On the basis of chemical evidences and spectral data analysis (UV, ECD, 1 D and 2 D-NMR, HR-ESI-MS), the structures of compound 1 was elucidated. Furthermore, all compounds have been tested for their inhibitory effects on NO production in LPS-induced RAW 264.7 cells, and compounds 6, 7, 11 and 13 have obvious inhibitory effect, in which the IC₅₀ value of compound 7 reached 11.63 ± 1.29 μM. Through target screening and molecular docking, we can speculate that compound 7 may exert its anti-inflammatory effect by binding to MAPKAP kinase 2 and Leukocyte Proteases Cathepsin G & Chymase.

Keywords:

• Phenylpropanoid-substituted epicatechin
• flavonoids
• lignin
• Smilax china
• circular dichroism
• anti-inflammation

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Additional information

Funding

The authors thank the National Natural Science Foundation of China (NSFC) (No. 82141216), Chunhui Program-Cooperative Research Project of the Ministry of Education, and Shenyang Young and Middle-aged Innovative Talents Support Program (No. RC210446) for financial supports.