Isolation of a new compound, 2-butanone 4-glucopyranoside 6′-O-gallate and other 8 compounds from the anti-inflammatory leave extracts of Memecylon edule Roxb

Abstract

This present study was designed to isolate the compounds of Memecylon edule. The chemical compounds were purified by chromatographic methods and their structures were established on the basis of spectroscopic analyses (UV, MS and NMR). The major isolated compounds were tested for anti-inflammatory activity. The methanolic extracts of M. edule leaves gave a new compound 2-butanone 4-glucopyranoside 6′-O-gallate (1) with eight known compounds, namely, 3,3′-di-O-methylellagic acid 4-O-β-d-glucopyranoside (2), epigallocatechin-3-O-gallate (EGCG) (3), (2R, 3R)–dihydromyricetin-4′-β-d-glucopyranoside (4), myricetin-3-O-α-l-rhamnopyranoside (5), benzyl-(6-O-α-L arabinofuranosyl) O-β-d-glucopyranoside (6), benzyl-(6-O-α-l-rhanmopyranosyl) O-β-d-glucopyranoside (7), 2-phenylethyl-(6-O-β-d-apiofuranosyl)-O-β-d-glucopyranoside (8) and methyl benzoate 2-(6-O-α-l-rhamnosyl)-O-β-d-glucopyranoside (9). All compounds were isolated for the first time from this plant. The major compounds (2, 3 and 5) exhibited significant anti-inflammatory activity. In conclusion, M. edule was recognised to be a good source for phenolic compounds and these compounds may contribute to anti-inflammatory activity of the extract.

Keywords:

• Memecylon edule
• isolation
• anti-inflammatory effect
• 2-butanone 4-glucopyranoside 6′-O-gallate
• 3,3′-di-O-methylellagic acid 4-O-β-d-glucopyranoside
• epigallocatechin-3-O-gallate