Description_x000D_ Application_x000D_ 4-Hydroxytolbutamide has been used as a standard to assay the fungal biotransformation of tolbutamide to 4′-hydroxytolbutamide._x000D_ Packaging_x000D_ 5, 10 mg in glass bottle_x000D_ Bottomless glass bottle. Contents are inside inserted fused cone._x000D_ Other Notes_x000D_ Metabolite of tolbutamide; formed by the cytochrome CYP2CIIC8 and IIC9 subfamily of P450 enzymes._x000D_ Preparation Note_x000D_ 4-Hydroxytolbutamide is soluble in ethanol at 12 mg/mL and is also soluble in 0.1 M NaOH at 4 mg/ml. It is insoluble in water.