7'-Amino-1'H-spiro[cycloheptane-1,2'pyrimido[4,5-d] pyrimidin]-4'(3'H)-one

The title compound, C12H17N5O, was obtained by cyclocondensation of 2,4-diaminopyrimidine-5-carbonitrile with cycloheptanone. The tetrahydropyrimidine ring has a distorted boat conformation and the cycloheptane ring adopts a chair conformation. In the crystal, molecules are linked via N- H center dot center dot center dot O and N-H center dot center dot center dot N hydrogen bonds generating a threedimensional network.