Four flavonols from the seed of Hibiscus sabdariffa Linn. growing in Binh Thuan Province

Tóm tắt

Introduction: Hibiscussabdariffa Linn. (Malvaceae) is a medicinal plant popularly distributed in Asian countries. As of 2019, no chemical investigations from the Vietnamese plant were found. This paper reported the isolation and elucidation of compounds isolated from the seeds ofHibiscussabdariffa Linn. (Malvaceae) growing in Binh Thuan province.

Method: The maceration was applied to the seeds of the plant to afford the crude extract which was then fractionated by liquid-liquid extraction to obtain the ethyl acetate extract. The extract was carried out by using normal phase silica gel column chromatography and thin-layer chromatography. Analysis of spectroscopic data including HR-ESI-MS, 1D and 2D-NMR and a comparison of the NMR data with that in the literature led to the structural elucidation of isolated compounds.

Results: Four flavonols comprising quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside (1), quercetin 3-O-β-D-glucopyranoside (2), quercetin (3) and kaempferol (4) were isolated from the ethyl acetate extract.

Conclusions: This is the first time the isolated compounds were found from the seeds of this plant