A novel fused heterocyclic system - Synthesis of substituted 9,10- dihydro- 1,3,4,6,7,10-hexaazacyclohepta[de]naphthalen-8(7H)-ones

Article abstract of DOI:10.1016/S0040-4020(98)00588-2

4-Amino-5-chloro-2,7-bis(dimethylamino)pyrimido[4,5-d]pyrimidine (5) was prepared starting from 1,1-diamino-2,2-dicyanoethylene (1) and dichloromethylenedimethylimmonium chloride (2). After reacting with α- aminoacidic esters, 5 was converted into a series of new pyrimido[4,5- d]pyrimidines (7), which underwent cyclization to yield substituted 9,10- dihydro-1,3,4,6,7,10-hexaazacyclohepta[de]naphthalen-8(7H)-ones (8).