Xylazine impurity C - 2,6-dimethylphenyl isothiocyanate

Ketotifen impurity G - 4-(1-methylpiperidin-4-ylidene)-4H-benzo(4,5)cyclohepta(1,2-b)thiophen-9,10-dione

Tramadol impurity A - (1RS,2SR)-2-[(dimethylamino)methyl]-1-(3-methoxyphenyl)cyclohexanol

Tramadol impurity E - (2RS)-2-[(dimethylamino)methyl]cyclohexanone

Tolfenamic acid

Tramadol hydrochloride

Tianeptine for system suitability

Tianeptine impurity A - ethyl 7-bromoheptanoate

Rifabutin

Tianeptine sodium - Reference Spectrum