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Updated: Jul 9, 2025
Author Spotlight: Discovering New Alkaloids in Plants with Advanced Mass Spectrometry Techniques
Published on: March 8, 2024
Limonoids and alkaloids from Tetradium austrosinense (Hand.-Mazz.) T.G.Hartley
Feng Han1, Jia-Ying Yao2, Jun-Jie Tan3
1School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China; Natural Product Research Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
Abstract:
A pair of new enantiomeric indolopyridoquinazoline-type alkaloids, (+)-1,7S,8R- and (-)-1,7R,8S-trihydroxyrutaecarpine (3a and 3b), and a new limonoid-tyrosamine hybrid, austrosinin (8), along with six known alkaloids and limonoids, were isolated from the stems with leaves of Tetradium austrosinense. Their structures were elucidated on the basis of analysis of MS, NMR, ECD and time-dependent density functional theory-based electronic circular dichroism (TDDFT-ECD) calculations, as well as proposed biosynthetic pathway. An anti-inflammatory bioassay in vitro showed 8 had significant immunosuppressive effect against the production of pro-inflammatory cytokine TNF-α in lipopolysaccharide (LPS)-stimulated RAW264.7 cells.
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