6,8-diamino-1H-pyrimido[5,4-g]pteridine-2,4-dione

2,4-diaminopyrido[2,3-d]pyrimidine-6-carbaldehyde

4-chloro-2-[(2,6-diaminopyrimidin-4-yl)amino]benzoic acid

6-methylpyrido[2,3-d]pyrimidine-2,4-diamine

6-[2-(2,4-dichlorophenoxy)ethoxy]-7,8-dihydro-5H-pyrimido[4,5-d]pyrimidine-2,4-diamine