- Br?nsted acid-mediated cyclization-dehydrosulfonylation/reduction sequences: An easy access to pyrazinoisoquinolines and pyridopyrazines
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An efficient and alternative synthetic approach has been developed to prepare various N-(arylethyl)piperazine-2,6-diones from 4-benzenesulfonyliminodiacetic acid and primary amines using carbonyldiimidazole in the presence of a catalytic amount of DMAP at ambient temperature. Piperazine-2,6-diones are successfully transformed to pharmaceutically useful pyridopyrazines or pyrazinoisoquinolines and ene-diamides via an imide carbonyl group activation strategy using a Br?nsted acid. Subsequent dehydrosulfonylation reactions of the ene-diamides, in a one pot manner, smoothly transformed them to substituted pyrazinones. A concise synthesis of praziquantel (1) has also been achieved through this method.
- Rao, Ramana Sreenivasa,Ramanathan, Chinnasamy Ramaraj
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- Synthesis and SAR studies of praziquantel derivatives with activity against Schistosoma japonicum
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The synthesis and structure-activity relationship (SAR) studies of praziquantel derivatives with activity against adult Schistosoma japonicum are described. Several of them showed better worm killing activity than praziquantel and could serve as leads for further optimization.
- Wang, Wen-Long,Song, Li-Jun,Chen, Xia,Yin, Xu-Ren,Fan, Wen-Hua,Wang, Gu-Ping,Yu, Chuan-Xin,Feng, Bainian
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p. 9163 - 9178
(2013/09/23)
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- Synthesis and Anthelmintic Activity of a Series of Pyrazinobenzazepine Derivatives
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A series of 1,2,3,4,6,7,8,12b-octahydropyrazinobenzazepine derivatives was prepared and the cestocidal activity of the compounds evaluated in an in vitro Taenia crassiceps screen.Many of these derivatives proved to be highly active, and 2-(cyclohexylcarbonyl)-4-oxo-1,2,3,4,6,7,8,12b-octahydropyrazinobenzazepine, epsiprantel (BAN) (22), was selected for further development.The structure-activity relationships are discussed.
- Brewer, Malcolm D.,Burgess, Malcolm N.,Dorgan, Roderick J. J.,Elliott, Richard L.,Mamalis, Patrick,et al.
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p. 2058 - 2062
(2007/10/02)
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