Bioactive constituents of Artemisia monosperma

During a study on the chemistry and biological activity of Kuwaiti plants, new metabolites including 4,6-dihydroxy-3-[3′-methyl-2′-butenyl]-5-[4″-hydroxy-3″-methyl-2″-butenyl]-cinnamic acid (1), the 3R,8R stereoisomer of the C17 polyacetylene dehydrofalcarindiol (2) and a C10 polyacetylene glucoside (3) were characterised by spectroscopic means. Additionally, the previously characterised natural products 1,3R,8R-trihydroxydec-9-en-4,6-yne (4), spathulenol (5) and eriodyctiol-7-methyl ether (6) were also isolated. Compounds 2, 3, and 4 were evaluated for their ability to inhibit the enzyme 12-lipoxygenase and 3 and 4 showed moderate activity at 30 μg/ml. Compound 2 was evaluated against a panel of colorectal and breast cancer cell lines and IC50 values ranged from 5.8 to 37.6 μg/ml. Against a panel of fast-growing mycobacteria and a standard ATCC strain of Staphylococcus aureus, compound 6 exhibited minimum inhibitory concentrations in the range of 64–128 μg/ml