Glycosides from Bougainvillea glabra

Abstract

Three glycosides were isolated from Bougainvillea glabra and their structures were determined by extensive use of 1D and 2D NMR spectroscopy (¹H and ¹³C). Compound 1 was identical to momordin IIc (quinoside D) [β-D-glucopyranosyl 3-O-[β-D-xylopyranosyl-(1 → 3)-O-(β-D-glucopyranosyluronic acid)] oleanolate], compound 2 was quercetin 3-O-α-L-(rhamnopyranosyl)(1 → 6)-[α-L-rhamnopy-ranosyl(1 → 2)]-β-D-galactopyranoside and compound 3 was its derivative quercetin 3-O-α-L-(4-caffeoylrhamnopyranosyl)(1 → 6)-[α-L-rhamnopyranosyl (1 → 2)]-β-D-galactopyranoside, a new natural product.

Keywords:

• Bougainvillea glabra
• Momordin IIc
• Quinoside D
• Flavanoid glycosides
• NMR

Acknowledgements

This work was supported by the Hungarian Academy of Sciences (Project MTA/DFG 2002–2004), by the Hungarian National Research Foundation (OTKA No. T046127) and by the Deutsche Forschungsgemeinschaft (436 UNG 113/148). This work has been performed within the project ‘Biologically Active Natural Products, Synthetic Diversity’ (Department of Chemistry, Hannover University).

Notes

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Additional information

Notes on contributors

Hesham S. M. Soliman*

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