Synthesis, Isolation and Characterization of Nine Pharmacopeial Impurities Related to the Active Pharmaceutical Ingredient Olsalazine Sodium

Abstract Olsalazine sodium is an anti-inflammatory agent used to treat ulcerative colitis. Both British and European Pharmacopoeia list nine process-related impurities in their monographs. Quantification of the impurities in the final synthesized active pharmaceutical ingredient (API) is required to meet the quality standards set by the International Council for Harmonisation (ICH). Both literature reports and commercial vendors for these impurities are few and far between. The present report describes the synthesis, isolation, purification and characterization of these nine pharmacopeial impurities.