Heterocycles

Nitrogen bridgehead compounds part 90. An efficient versatile synthesis of 1-methyl-2-substituted 1, 2, 3, 4-tetrahydro-6H-pyrazino [2, 1-b] quinazoline-3, 6-diones

J Kökösi, J Almási, B Podányi, M Fehér, Z Böcskei…

文献索引：Koekoesi, Jozsef; Almasi, Janos; Podanyi, Benjamin; Feher, Miklos; Boecskei, Zsolt; et al. Heterocycles, 1998 , vol. 48, # 9 p. 1851 - 1866

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被引用次数: 6

摘要

A versatile synthesis of 2-substituted 1-methyl-and 1, 4-dimethyl-1, 2, 3, 4-tetrahydro-6H- pyrazino [2, 1-b] quinazoline-3, 6-diones is presented, starting from 2-(1-bromoethyl) quinazolin-4 (3H)-one. The key step of the reaction sequence is the diastereoselective cyclization of 2-{[1-(N-2-haloacyl-N-substituted amino] ethyl} quinazolin-4 (3H)-ones. Usually 1, 4-dimethyl derivatives are obtained as pure racemic cis-compounds (2-alkyl ...