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Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade
Published on: August 14, 2019
A new prenylated flavanone from Derris trifoliata Lour
Cheng Jiang1, Shengzi Liu, Weihong He
1Department of Pharmacy, Medical College, Hunan Normal University, Changsha 410006, China. dangdangli@tom.com
Abstract:
A new flavanone, 4',5,7-trihydroxy-6,8-di-(2-hydroxy-3-methylbut-3-enyl)- flavanone, was isolated from the aerial parts of Derris trifoliate, together with eleven known compounds: rotenone, tephrosin, 12a-hydroxyrotenone, deguelin, 6a,12a-dehydro-rotenone, dehydrodeguelin, 7a-O-methyldeguelol, 7a-O-methylelliptonol, 5,7,3',4'-tetra-hydroxy-6,8-diprenylisoflavone, daidzein and 4'-hydroxy-7-methoxyflavanone. 7a-O-Methylelliptonol was isolated for the first time from the genus Derris. Their structures were characterized on the basis of spectral data. Eight of the isolated compounds were found to be significantly toxic to brine shrimp (LC(50) range 0.06-9.95 μg/mL). The new compound showed weak toxicity (LC(50) = 211.31 μg/mL).
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