Chemical and antibacterial constituents of Skimmia anquetelia

Investigation of the leaves of Skimmia anquetelia (Rutaceae) led to the isolation of a new coumarin glucoside 7,8-dihdroxy-6-[3′-β-D-glucopyranosyloxy-2′(ξ)-hydroxy-3’-methylbutyl]-coumarin (1) together with five known coumarins: 6-(2,3-dihydroxy-3-methylbutyl)-7-methoxycoumarin (2), skimmin (3), osthol (4), esculetin (5) and scopuletin (6). The antibacterial activity of compounds 1 and 3 was also investigated against the plant bacterial pathogens Agrobacterium tumifaciens, Pseudomonas syringae and Pactobacterium carotovorum. Structures were determined on the basis of analyses of spectral evidence including 1D, 2 D NMR (COSY, HMQC, HMBC and NOESY) and mass spectroscopy.