Peraksine derivatives with potential anti-inflammatory activities from the stems of Rauvolfia vomitoria

• Published in: Fitoterapia 2020-10, Vol.146, p.104704-7, Article 104704
• Main Authors: Zhan, Guanqun, Miao, Rongkun, Zhang, Fuxin, Hao, Yi, Zhang, Yu, Zhang, Yingxu, Khurm, Muhammad, Zhang, Xinxin, Guo, Zengjun
• Format: Article
• Language: English
• Subjects: Acetylcholinesterase; Alkaloids; Anti-inflammatory activity; Apocynaceae; Chlorine; Cytotoxicity; Derivatives; Indoles; Inflammation; Lipopolysaccharides; Macrophages; Monoterpene indole alkaloids; Peraksine derivatives; Predation; Rauvolfia vomitoria; Stems
• ISSN: 0367-326X; 1873-6971
• DOI: 10.1016/j.fitote.2020.104704

Five new peraksine derivatives rauvomine C–G (1–5) along with four known analogues (6–9) were isolated from the stems of Rauvolfia vomitoria Afzel. (Apocynaceae). Structural determinations of the new monoterpene indole alkaloids were elucidated via comprehensive spectroscopic analyses and ECD calculations. Rauvomine C (1) with an unprecedented framework type represents the first example of C18 peraksine-type nor-monoterpene indole alkaloid featuring a chlorine atom at C-16 and its plausible biosynthetic pathway was also proposed. All the isolates were evaluated for their anti-inflammatory, cytotoxic, and acetylcholinesterase inhibitory activities. Among them, the new framework alkaloid rauvomine C (1) showed significant anti-inflammatory activities on NO production in LPS-induced RAW264.7 mouse macrophages with IC50 value of 10.76 μM. Additionally, peraksine-type alkaloids featuring pyran ring (5, 8, and 9) exhibited potential anti-inflammatory activities with IC50 values ranging from 17.52 to 20.99 μM. [Display omitted] •Five new peraksine derivatives were isolated from Rauvolfia vomitoria.•1 was a novel C18 peraksine-type nor-monoterpene indole alkaloid with a chlorine atom.•New framework alkaloid rauvomine C showed significant anti-inflammatory activities.•Peraksine derivatives exhibited potential anti-inflammatory activities