| Abstract: | A convenient method is proposed for the synthesis of the alkaloid ellipticine, which possesses a pronounced antitumoral activity. The interaction of 3-bromocyclohexene (1 equiv.) and 2,5-xylylidine (4 equiv., 150°C, 5 h) gave a mixture of hexa- and tetrahydrocarbazoles which was dehydrogenated in the presence of Pd/C to the key synthon 1,4-dimethylcarbazole. The formylation of the carbazole by the Vilsmeier-Haack reaction, interaction with 2,2-diethoxyethylamine, and reduction of the imine formed over Raney nickel led to 3-(2,2-diethoxyethylaminomethyl)-1,4-dimethylcarbazole, the boiling of the N-tosylate of which gave ellipticine in high yield. Institute of Organic Chemistry, Urals Branch, Russian Academy of Sciences, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 549–554, September–October, 1992. |
