Imidazo[5,1-f][1,2,4]triazin-4(1H)-one, 2-[2-ethoxy-5-[(4-ethyl-4-oxido-1-piperazinyl)sulfonyl]phenyl]-5-methyl-7-propyl- Vardenafil IMpurity 1 Imidazo[5,1-f][1,2,4]triazin-4(1H)-one, 2-[5-[(4-ethyl-1-piperazinyl)sulfonyl]-2-hydroxyphenyl]-5-methyl-7-propyl- 7-Despropyl 7-Methyl Vardenafil 2-(2-ETHOXYPHENYL)-5-METHYL-7-PROPYL-3H-IMIDAZOL[5,1-F][1,2,4]-TRIAZIN-4-ONE 2,2'-((piperazine-1,4-disulfonyl)bis(2-ethoxy-5,1-phenylene))bis(5-methyl-7-propylimidazo[5,1-f][1,2,4]triazin-4(3H)-one) Vardenafil Impurity 5 3-(1,4-Dihydro-5-Methyl-4-oxo-7-propyliMidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxybenzenesulfonic Acid Vardenafil Impurity 15 Imidazo[5,1-f][1,2,4]triazin-4(1H)-one, 2-[5-[(4-ethyl-1-piperazinyl)sulfonyl]-2-propoxyphenyl]-5-methyl-7-propyl- Vardenafil Impurity 15 Hydroxythiovardenafil 3-(1,4-Dihydro-5-Methyl-4-oxo-7-propyliMidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxybenzoic Acid Hydroxyvardenafil Vardenafil Impurity 7 N-Desethyl Vardenafil Vardenafil Oxopiperazine (IMpurity)