Sulfadiazine (Standard) is the standard substance of Sulfadiazine, and it is applicable for quantitative analysis, quality control, and related research in biochemical experiments. Sulfadiazine (Sulphadiazine) is a synthetic pyrimidinyl sulfonamide derivative, short-acting bacteriostatic Sulfadiazine inhibits bacterial folic acid synthesis by competing with para-aminobenzoic acid. It is used in combination with pyrimethamine to treat toxoplasmosis in patients with acquired immunodeficiency syndrome and in newborns with congenital infections.