7-(2-acetamido-4,6-di-O-acetyl-2,3-dideoxy-D-threo-hex-2-enopyranosyl)theophylline

5-bromo-1,3-dimethyl-6-methylamino-1H-pyrimidine-2,4-dione

N-(1,3-Dimethyl-6-nitro-2,4-dioxo-1,2,3,4-tetrahydro-pyrimidin-5-yl)-formamide

1,3-dimethylxanthine-9-carbonitrile

6-amino-1,3-dimethyl-5-phenylazouracilate