Impurity standards are well-characterized reference materials used in pharmaceuticals and chemicals to identify, quantify, and control impurities in drug substances and finished products. They help ensure product quality, safety, regulatory compliance, and consistency during manufacturing and testing.

CAS Number
1315629-79-8 (Na Salt)
Alternate CAS Number
873950-18-6 (Free Base ) ; 3085658-74-5(calcium salt)
CAS Number
433289-84-0
Alternate CAS Number
433289-83-9(Ca Salt);1516864-05-3(sodium salt)
CAS Number
693794-20-6
Alternate CAS Number
693793-53-2(Ca Salt);1807481-00-0(sodium salt)