5-(2-Ethoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3d]pyrimidin-7-one

5-(2-ethoxyphenyl)-1-methyl-3-propyl-1,6-dihydro-7h-pyrazolo[4,3-d]-7-pyrimidinone ; 5-(2-ethoxyphenyl)-1-methyl-3-propyl-1h-pyrazolo[4,3-d]pyrimidin-7(6h)-one ; 7h-pyrazolo[4,3-d]pyrimidin-7-one,5-(2-ethoxyphenyl)-1,4-dihydro-1-methyl-3-propyl- ; uk 088800 ; 5-(2-ethoxyphenyl)-1-methyl-3-n-propyl-1 ; 5-(2-ethoxyphenyl)-1-methyl-3-propyl-6h-pyrazolo[4,3-d]pyrimidin-7-one ; 5-(2-ethoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7h-pyrazolo[4,3-d]pyrimidin-7-one ; sildenafil lactam impurity ; 5-(2-ethoxyphenyl)-1-methyl-3-propyl-1,4-dihydro-7h-pyrazolo[4,3-d]pyrimidin-7-one ; 5-(2-ethoxyphenyl)-1-me-3-n-propyl-1,6-dihydro-7h-pyrazolo(4,3d)-7-pyrimidin