1-methyl-5-((5-methyl-2-phenyl-2H-1,2,3-triazol-4-yl)methylamino)-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-7(6H)-one

1'-methyl-5-(methyl((4-methyl-2-phenylthiazol-5-yl)methyl)amino)-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-7(6H)-one

5-((3,4-dichlorobenzyl)(isopentyl)amino)-1-methyl-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-7(6H)-one

5-(6,7-dimethoxy-1-methyl-3,4-dihydroisoquinolin-2(1H)-yl)-1-methyl-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-7(6H)-one

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