An Antibacterial Isovaleronitrile Diglycoside From Detarium microcarpum Guill. Perr. (Fabaceae)

Abstract

A new isovaleronitrile diglycoside, named microcarposide (1), together with 6 known compounds: lupeol (2), betulinic acid (3), β-sitosterol glucoside (4), methyl gallate (5), luteolin (6), and epicatechin (7), was isolated from the methanolic extract of the fruits of Detarium microcarpum Guill. Perr. The structures of the compounds were determined by extensive analysis of 1D- and 2D-1H and 13C NMR spectroscopic data in conjunction with mass spectrometry and by comparison with data reported in the literature. Compound 1 was characterized as (2 R)-2-[(6″- O-β-l-rhamnopyranosyl-β-d-glucopyranosyl)oxy]-3-methylbutanenitrile. Some of the isolated compounds were evaluated for their antibacterial activities against several microorganisms; only compound 1 was active against Salmonella typhi, Salmonella enteritidis, and Salmonella typhimurium with minimum inhibition concentration values of 153.4, 76.7, and 76.7 μM, respectively.