10-(1H-Benzimidazol-2-ylsulfanyl)-1-methyl-2-(2,2,2-trifluoroethoxy)-4a,5,9btriazaindeno[2,1-a]indene,10-(1H-Benzimidazol-2-ylsulfanyl)-1-methyl-2-(2,2,2-trifluoroethoxy)-4a,5,9btriazaindeno[2,1-a]indene,Impurity in commercial preparation of Lansoprazole.,Lansoprazole Therapeutic