6-(2-Methoxy-phenylamino)-3-methyl-1,6-dihydro-pyrazolo[4,3-d]pyrimidin-7-one
6-(2-Chloro-phenylamino)-3-methyl-1,6-dihydro-pyrazolo[4,3-d]pyrimidin-7-one
6-(3-Chloro-phenylamino)-3-methyl-1,6-dihydro-pyrazolo[4,3-d]pyrimidin-7-one
3-Methyl-6-p-tolylamino-1,6-dihydro-pyrazolo[4,3-d]pyrimidin-7-one
3-Methyl-6-m-tolylamino-1,6-dihydro-pyrazolo[4,3-d]pyrimidin-7-one