The dolabellane-type diterpene alkaloids, nigellamines A1~A5、B1~B2 and C, were isolated from the methanolic extract of an Egyptian medicinal food, black cumin(the seeds of Nigella sativa).
The seeds of this plant have been used as a food and spice and also prescribed in Egyptian folk medicine for the treatment of asthma, flatulence, polio, kidney stones, abdominal pain, etc.
Nigellamines A1、A5、B1 and B2 were found to show potent lipid metabolism promoting activity in primary cultured mouse hepatocytes. The triglyceride levels were reduced to 64% at 0.1 μM in vitro by nigellamines A1 and A5. Their activities were equivalent to that of a hypolipidemic medicine, clofibrate which acts as a PPAR-α agonist.
The structures of Nigellamines have a dolabellane-type diterpene skeleton and
the major difference is esteroid of them. To date, the absolute stereostructures of Nigellamines have been elucidated and lipid metabolism promoting activities have also been reported. Accordingly, we will develop a systemic procedure to synthesize Nigellamines and study other bioactivity of their derivatives.
