A new phenolic glycoside from the leaves of Flacourtia flavescens Willd

Abstract

Chemical study of the methanol extract from the leaves of Flacourtia flavescens led to the isolation of a new phenolic glucoside (1) along with fifteen known secondary metabolites namely shanzhiside methyl ester (2), aurantiamide acetate (3), caffeic acid methyl ester (4), caffeic acid (5), apigenin (6), luteolin (7), kaempferol (8), quercetin (9), gyrophoric acid (10), luteolin-7-O-β-D-glucopyranoside (11), luteolin-4’-O-β-D-glucopyranoside (12), kaempferol-7-O-α-L-rhamnopyranoside (13), kaempferol-3-O-β-D-glucopyranosyl-(1$\to$6)-O-α-L-rhamnopyranoside (14), kaempferol-3,7-O-α-L-dirhamnopyranoside (15) and (2S,3S,4R,8E)-2-((2′R)-2′-hydroxy-octadecanoylamino)-lignocerane-1,3,4-triol-8-ene (16). Their structures were elucidated by 1D and 2D NMR analysis and mass spectrometry. The extracts and the isolated compounds were evaluated for their antibacterial activities. The EtOAc extract was highly active (MIC = 32 and 64 µg/mL) against E. coli and E. faecalis, respectively. Compounds 1, 2, 2b, 5, 8, 9, and 12 (MIC = 16–32 µg/mL) were moderately active against some tested bacteria.

Graphical Abstract

Keywords:

• Flacourtia flavescens
• phenolic glucoside
• Flacourtiaceae
• antibacterial activity

Disclosure statement

The authors declare no conflict of interest.

Additional information

Funding

This study is supported by Alexander Von Humbolt Foundation (AvH), Bonn, Germany (Ref 3.4-1157152-CMR-GFHERMES-E and 3.4-CMR-Hub); Rhineland Palatinate Centre of Natural Products Research (Mainz, Germany)