6′-Bromo-1′H-spiro­[cyclo­hexane-1,2′-pyrido[2,3-d]pyrimidin]-4′(3′H)-one

The title compound, C₁₂H₁₄BrN₃O, is built up from two fused six-membered rings and one six-membered ring linked through a spiro C atom. The hydro­pyrimidine ring has an envelope conformation and the cyclo­hexane ring is in a chair conformation. In the crystal, mol­ecules are linked by N—H...O and N—H...N hydrogen bonds, forming a mol­ecular tape along the b axis.