2-butylsulfanyl-7H-purin-6-amine

3-methylimidazo[4,5-c]pyridine

4,6,7-trimethyl-1,4-dihydroquinazoline-8-carbonitrile

4,5-diethyl-1H-imidazole

4-amino-9-(β-D-ribofuranosyl)pyrrolo<2,3-d:5,4-d'>dipyrimidine