Clausena 3-methylcarbazole

The dimeric carbazole alkaloids often occur along with the corresponding monomeric carbazoles in terrestrial plants [7,62] (Scheme 7). Clausenamine-A was obtained by Wu from the stem bark of Clausena excavata [63]. Clausen-amine-A and its synthetic analogs, like bis(O-demethylmurrayafoline-A), show cytotoxic activities against diverse human cancer cell lines [64] and exhibit moderate antimalarial activity [65,66]. Furukawa isolated l,r-bis(2-hy-droxy-3-methylcarbazole) and bismurrayaquinone-A, the first dimeric car-bazolequinone alkaloid found in nature, from Murraya koenigii [67]. 

Non-tryptamines.—The number of carbazole derivatives isolated from the Rutaceae is now fourteen. Besides the tricyclic compounds murrayanine " (3-formyl-l-methoxycarbazole), glycozoline " (3-methoxy-6-methylcarbazole), glycozolidine " (2,4-dimethoxy-6-methylcarbazole), and (from Clausena hepta-phylla) heptaphylline (1), tetra- and penta-cyclic carbazoles have been obtained from Murraya koenigU3 ... 

Formyl-1-methoxycarbazole (murrayanine) and 3-methylcarbazole (for the first time from natural sources) have been isolated from Clausena heptaphylla Heptazolidine/ a new alkaloid from the same source, has been given the structure (44). Its dihydro-derivative has a u.v. absorption said to be similar to that of 2,3-dimethoxycarbazole. 

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