Four New Antibacterial Constituents from Senecio cannabifolius.

Abstract

Four novel chemical constituents, cannabiside B, cannabiside C, cannabiloid B, and cannabilactone A, have been isolated from the n.-butanol extract of the herb of Senecio cannabifolius. Less. (Compositae). The structures of the isolated compounds were established as 3-[3,4-dihydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl]-5-hydroxyfuran-2(5H)-one (1), 8,10-dihydroxy-7-(hydroxymethyl)-4-methyl-1, 6-dioxaspiro [4.5] dec-3-en-2-one (2), 6-(1,2-dihydroxy-ethyl)-3-[3-(3,4-dihydroxy-5-hydroxymethyl-tetrahydro-furan-2-yl)-5-hydroxy-pyrrol-2-ylidene]-4-hydroxy-tetrahydro-pyran-2-one (3), and 5-hydroxy-3-{[5-(hydroxylmethyl)furan-2-yl] methylene} benzofuran-2(3H)-one (4), respectively, by spectroscopic (UV, IR, NMR, and MS) methods. All the compounds showed antibacterial activities against Staphylococcus aureus. and Bacillus subtilis. but not Escherichia coli..

Keywords:

• Agar-well diffusion assay
• antibacterial activity
• Compositae
• minimum inhibitory concentration
• Senecio cannabifolius