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Updated: May 23, 2025

Author Spotlight: Discovering New Alkaloids in Plants with Advanced Mass Spectrometry Techniques
Published on: March 8, 2024
Two New Halimanes with a γ-Lactone from Croton argyratus
Kanami Watanabe1, Yohei Saito1, Shuichi Fukuyoshi1
1School of Pharmacy, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan.
Abstract:
The phytochemical investigation of the rainforest plant Croton argyratus (Euphorbiaceae) led to the isolation of two halimane-type diterpenes, crotargyolides A (1) and B (2), with an uncommon γ-lactone ring at C-5 and C-9, together with a crotofolane-type diterpene, 3-hydroxylated crotofolin C (3, crokocrotogenoid A), and the known clerodane diterpenes, junceic acid (4) and epoxyjunceic acid (5). The structures of the newly isolated compounds were elucidated by various NMR techniques, high resolution (HR)MS analysis, and electronic circular dichroism (ECD) spectroscopy. The proposed biosynthetic pathway of 1 from 4 was discussed. Crotargyolide A (1) and known compounds 4 and 5 were evaluated for antiproliferative activity and displayed no growth inhibitory effect toward all tested tumor cell lines.
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