Tadalafil Impurity 39

(1R,3R)-1-(1,3-benzodioxol-5-yl)-2-(2-chloroacetyl)-2,3,4,9-tetrahydro-1H-Pyrido[3,4-b]indole-3-carboxylic acid is an impurity of Tadalafil (T004500), which is used for the treatment of erectile dysfunction. A phosphodiesterase 5 inhibitor.