2-[2-Ethoxy-5-[2-(4-ethyl-1-piperazinyl)acetyl]phenyl]-5-methyl-7-propyl-imidazo[5,1-f][1,2,4]triazin-4(1H)-one ; CAS # 1261351-28-3 ;

3-(1,4-Dihydro-5-methyl-4-oxo-7-propylimidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxybenzoic acid ; CAS # 358390-39-3 ;

4-Ethoxy-3-(5-methyl-4-oxo-7-propyl-3,4-dihydro-imidazo[5,1-f][1,2,4]-triazin-2-yl)benzenesulfonyl chloride ; CAS # 224789-26-8 ;

2-(2-Ethoxyphenyl)-5-methyl-7-propyl-3H-imidazo[5,1-f][1,2,4]triazin-4-one ; CAS # 224789-21-3 ;

1-[[3-(1,4-Dihydro-5-methyl-4-oxo-7-propylimidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxyphenyl]sulfonyl]-4-ethyl-piperazine dihydrochloride ; CAS # 224789-15-5 ;

2,2�-[Sulfonylbis(6-ethoxybenzene-3,1-diyl)]bis(5-methyl-7-propylimidazo [5,1-f][1,2,4]triazin-4(3H)-one) ;

7-Methyl Vardenafil (USP) ; 1-[[3-(1,4-Dihydro-4-oxo-5,7-dimethylimidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxyphenyl]sulfonyl]-4-ethyl-piperazine ;

Vardenafil Acid (USP) ; Vardenafil Desethylpiperazinyl Sulfonic Acid ; 3-(1,4-Dihydro-5-methyl-4-oxo-7-propylimidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxybenzenesulfonic acid ; CAS # 437717-43-6 ;

Vardenafil EP Impurity C ; Vardenafil Dimer (USP) ; Vardenafil bis-Sulfonamide Dimer ; CAS # 1255919-03-9 ;

1-[[3-(1,4-Dihydro-5-methyl-4-oxo-7-propylimidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxyphenyl]sulfonyl]-4-hydroxyethyl-piperazine ; CAS # 224785-98-2 ;

Hydroxythiovardenafil ; 2-[2-Ethoxy-5-[[4-(2-hydroxyethyl)-1-piperazinyl]sulfonyl]phenyl]-5-methyl-7-propylimidazo[5,1-f][1,2,4]triazine-4(1H)-thione ; CAS # 912576-30-8 ;

1-[[3-(1,4-Dihydro-5-methyl-4-oxo-7-propylimidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxyphenyl]sulfonyl]-piperazine ; CAS # 448184-46-1 ;

2-[2-Ethoxy-5-[(3-oxo-1-piperazinyl)sulfonyl]phenyl]-5-methyl-7-propyl-imidazo[5,1-f][1,2,4]triazin-4(1H)-one ; CAS # 448184-58-5 ;

1-[[3-(1,4-Dihydro-5-methyl-4-oxo-7-propylimidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxyphenyl]sulfonyl]-4-ethyl-4-oxido-piperazine ; CAS # 448184-48-3 ;