Meroterpenoids with diverse structures and anti-inflammatory activities from Rhododendron anthopogonoides

Qing Shi; Teng-Teng Li; Yong-Mei Wu; Xin-Yu Sun; Chun Lei; Jing-Ya Li; Ai-Jun Hou

doi:10.1016/j.phytochem.2020.112524

Meroterpenoids with diverse structures and anti-inflammatory activities from Rhododendron anthopogonoides

Phytochemistry. 2020 Dec:180:112524. doi: 10.1016/j.phytochem.2020.112524. Epub 2020 Oct 7.

Authors

Qing Shi¹, Teng-Teng Li², Yong-Mei Wu³, Xin-Yu Sun³, Chun Lei¹, Jing-Ya Li⁴, Ai-Jun Hou⁵

Affiliations

¹ School of Pharmacy, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 201203, China.
² School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China; Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
³ Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China.
⁴ Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China; University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address: jyli@simm.ac.cn.
⁵ School of Pharmacy, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 201203, China. Electronic address: ajhou@shmu.edu.cn.

PMID: 33038550
DOI: 10.1016/j.phytochem.2020.112524

Abstract

Eight pairs of meroterpenoid enantiomers and four achiral meroterpenoids were isolated from Rhododendron anthopogonoides Maxim. Seventeen of them, named (+)-/(-)-anthoponoids A-G, (+)-daurichromene D, and anthoponoids H and I, are undescribed compounds with structural diversity. Their structures were characterized herein by a combined application of spectroscopic techniques, X-ray crystallographic analysis, ECD calculation, and the modified Mosher's method. (+)-/(-)-Anthoponoid A and anthoponoid I are the first Rhododendron meroterpenoids found to possess a hexahydroxanthene motif and a diterpene unit, respectively. Some isolates were identified as NF-κB pathway inhibitors, and (+)-anthoponoid E, (-)-anthoponoid G, and anthoponoid H showed suppressive effects on LPS-induced inflammatory responses in RAW 264.7 macrophages.

Keywords: Anthoponoids A−I; Anti-inflammation; Daurichromene D; Ericaceae; Meroterpenoids; Rhododendron anthopogonoides Maxim..

MeSH terms

Anti-Inflammatory Agents / pharmacology
Crystallography, X-Ray
Diterpenes
Rhododendron*
Stereoisomerism

Substances

Anti-Inflammatory Agents
Diterpenes