Tadalafil EP Impurity I

Tadalafil EP Impurity I

(8a′R)-6′-(1,3-Benzodioxol-5-yl)-2′-methyl-2′,3′,8′,8a′-tetrahydro-6′H-spiro[indole-3,7′-pyrrolo[1,2-a]pyrazine]-1′,2,4′(1H)-trione

Impurity reference standard used for related substances testing of Tadalafil drug substance and drug product per pharmacopoeial limits.