作者:M. V. Vovk、O. V. Kushnir、N. V. Melˈnichenko、I. F. Tsymbal
DOI:10.1007/s10593-011-0865-2
日期:2011.11
Cyclocondensation of 3-alkoxycarbonylmethylidenepiperazin-2-ones with alpha-chlorobenzyl isocyanates gave alkyl 8-aryl-1,6-dioxo-1,3,4,6,7,8-hexahydro-2H-pyrazino[1,2-c]pyrimidine-9-carboxylates. The use of 1-aryl-2,2,2-trifluoroethyl isocyanates in an analogous cyclization gave 6-aryl-1,8-dioxo-6-trifluoromethyl-1,3,4,6,7,8-hexahydro-2H-pyrazino[1,2-c]pyrimidine-9-carboxylates.