Nigellamines A3, A4, A5, and C, new dolabellane-type diterpene alkaloids, with lipid metabolism-promoting activities from the Egyptian medicinal food black cumin

Abstract

New dolabellane-type diterpene alkaloids, nigellamines A3, A4, A5, and C, were isolated from the methanolic extract of an Egyptian medicinal food, black cumin (the seeds of Nigella sativa). Their absolute configurations were determined on the basis of chemical and physicochemical evidence. Nigellamines were found to lower triglyceride levels in primary cultured mouse hepatocytes, and in particular, the activity of nigellamine A5 was equivalent to that of the hypolipidemic agent, clofibrate. © 2004 Pharmaceutical Society of Japan.