Spectrum Chemical manufactures and distributes fine chemicals with quality you can count on including those with CAS number 57-68-1, Whether you call it Sulfamethazine, N1-(4 -6-Dimethylpyrimidin-2-yl)sulfanilamide , Sulfadimerazine or Sulfadimidine you can be assured the Sulfamethazine products offered by Spectrum, meet or exceed the grade requirements or specifications for each individual product.