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Updated: Jul 15, 2026

High-resolution Tandem Mass Spectrometry for Studying Chemical Constituents of Gynura bicolor DC
Published on: February 2, 2024
Polyoxygenated cyclohexane derivatives and other constituents from Kaempferia rotunda L
Philip C Stevenson1, Nigel C Veitch, Monique S J Simmonds
1Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK. p.stevenson@kew.org <p.stevenson@kew.org>
Abstract:
Methanol extracts of Kaempferia rotunda L. rhizomes yielded seven compounds including six polyoxygenated cyclohexane derivatives identified as (-)-6-acetylzeylenol (1), four acylated derivatives of 1-benzoyloxymethyl-1,6-epoxycyclohexan-2,3,4,5-tetrol (3-6), a Diels-Alder adduct of 3-benzoyl-1-benzoyloxymethylcyclohexa-4,6-dien-2,3-diol (7), and a triacylated derivative of salicin (9). The cyclohexane diepoxide, crotepoxide (8), was also obtained. Spectroscopic methods were used for structure determination. The methanol extract of the rhizomes of K. rotunda and (-)-2-acetyl-4-benzoyl-1-benzoyloxymethyl-1,6-epoxycyclohexan-2,3,4,5-tetrol (2-acetylrotepoxide B; 6), had antifeedant activity against larvae of Spodoptera littoralis. (-)-Zeylenol (2) also showed antifeedant activity, whereas (-)-6-acetylzeylenol (1) was inactive.
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