English name: SildenafilChem.Name:5-[2-Ethoxy-5-(4-methylpiperazin-1-yl-sulphonyl)phenyl]-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazol[4,3d]pyrimidin-7-oneCAS#:139755-83-2Molecular Formula: C22H30N6O4SMolecular Weight: 474.58Appearance: white crystal powderAssay:99.5%min Melting point: 186-187℃Dry loss weight: ≤2.5%Cauterant residue: <0.05%Heavy metal: ≤20ppm Package: 25kg/cardboard drum