Detail of "5367-32-8"

Reference

A versatile and efficient construction of the 6H-pyrido[4,3-b]carbazole ring system

A versatile and efficient construction of the 6H-pyrido[4,3-b]carbazole ring system. Syntheses of the antitumor alkaloids ellipticine, 9-methoxyellipticine, and olivacine, and their analogs. Gribble, Gordon W.; Saulnier, Mark G.; Obaza-Nutaitis, Judy A.; Ketcha, Daniel M. (Dep. Chem., Dartmouth Coll., Hannover, NH 03755, USA). J. Org. Chem., 57(22), 5891-9 (English) 1992. CODEN: JOCEAH. ISSN: 0022-3263. DOCUMENT TYPE: Journal CA Section: 31 (Alkaloids) A general and efficient synthesis of the 6H-pyrido[4,3-b]carbazole ring system is described, in which the key steps are (1) regioselective acylation of a 2-lithio-1-(phenylsulfonyl)indole with 3,4-pyridinedicarboxylic acid anhydride, (2) cyclization of the deprotected keto acid I to keto lactam II with acetic anhydride, and (3) the addn. of methyllithium to give, after redn. of the intermediate diol III with sodium borohydride, the target ring system. In this fashion, ellipticine (IV, R = H), 9-methoxyellipticine (IV, R = MeO), and 9-hydroxyellipticine (IV, R = OH) were synthesized in excellent overall yields from indole. The use of Superhydride, in place of 1 equiv of methyllithium, provided a synthesis of olivacine and the use of phthalic anhydride in the sequence allowed for the prepn. of 6,11-dimethylbenzo[b]carbazole. The overall yields of ellipticine (54%) and 9-methoxyellipticine (47%) in six steps from their resp.Several substances like 5367-32-8 may be metioned in this study. indoles represent one of the most efficient syntheses of these antitumor alkaloids. .