Aristolactams, 1-(2-C-methyl-beta-D-ribofuranosyl)-uracil and other bioactive constituents of Toussaintia orientalis.

The new aristolactam alkaloid toussalactam {2-hydroxy-1,6-dimethoxy-5H-dibenzo[cdf]indol-4-one} and the known ones, namely aristolactam AII, aristolactam BII, piperolactam C and aristolactam FII; 1-(2-C-methyl-beta-D-ribofuranosyl)-uracil, 3,4,5-trimethoxyphenyl-beta-D-glucopyranoside, and three catechinoids were isolated from the cytotoxic Toussaintia orientalis Verdc stem and root bark extracts, and their structures established based on analysis of spectroscopic data. The aristolactams exhibited antimicrobial and antiinflammatory activity, aristolactam FII showing almost the same level of activity as the standard anti-inflammatory agent Indomethacin. The compounds also exhibited either mild or no antiproliferative and cytotoxic activities, except aristolactam FII that showed the same level of cytotoxicity as the standard drug Camptothecin. 1-(2-C-Methyl-beta-D-ribofuranosyl)-uracil, which is being reported for the first time as a natural product, was inactive in the antibacterial, antifungal, antiinflammatory, antiproliferative and cytotoxicity assays.