2,6,9-tris(trimethylsilyl)guanine

acyclovir P-(O-isopropyl) hydrogenphosphonate

3-(2-hydroxyethoxymethyl)-6-methyl-5H-imidazo[1,2-a]purin-9-one

3-[(2-acetoxyethoxy)methyl]-6-methyl-3,9-dihydro-5H-imidazo[1,2-a]purin-9-one

7-formamido-5-(methylthio)furazano[3,4-d]pyrimidine