Oxidative burst inhibitory and cytotoxic indoloquinazoline and furoquinoline alkaloids from Oricia suaveolens.

Two new β-indoloquinazoline alkaloids, orisuaveoline A (1) and orisuaveoline B (2), two new furoquinoline alkaloids, quinosuaveoline A (5) and quinosuaveoline B (6), and 12 known compounds were isolated from Oricia suaveolens. The structures of the new compounds were deduced by spectroscopic studies. The absolute configuration of nkolbisine (4) was also determined. Compounds 2, 3, 6-8, 10, and 14 were evaluated for oxidative burst inhibitory activity in a chemoluminescence assay and for cytotoxicity against A549 lung carcinoma cells.