Nicergoline impurity D - 5-bromopyridine-3-carboxylic acid

Prednisolone for system suitability

Betaxolol impurity C - 2-[[4-[2-(cyclopropylmethoxy)ethyl]phenoxy]methyl]oxirane ***

Nicergoline for system suitability

Phenobarbital impurity B - (5RS)-5-ethyl-6-imino-5-phenyldihydropyrimidine-2,4(1H,3H)-dione

Phenobarbital impurity A - (5RS)-5-ethyl-2,6-diimino-5-phenyltetrahydropyrimidin-4(1H)-one

Gabapentin impurity D - [1-[(3-oxo-2-azaspiro[4.5]dec-2-yl)methyl]cyclohexyl]acetic acid

Gabapentin impurity B - (1-cyanocyclohexyl)acetic acid

Ginsenoside Rb1

Ondansetron impurity G - (3RS)-3-[(1H-imidazol-1-yl)methyl]-9-methyl-1,2,3,9-tetrahydro-4H-carbazol-4-one (C-demethylondansetron)