Sulfacetamide sodium MF C8H13N2NaO4S MW 256.25 CAS 6209-17-2 Product description N-(4-Aminobenzenesulfonyl)acetamide sodium salt, an organic chemical substance, molecular formula: C8H9N2NaO3S. Sulfacetamide is a sulfonamide antibiotic that blocks the synthesis of dihydrofolate by inhibiting dihydropteroatesynthase (DHPS). ChemicalbookSulfacetamide is a competitive inhibitor of bacterial para-aminobenzoic acid (PABA), which is necessary for bacterial synthesis of folic acid.