Five potential USP grade levothyroxine impurities i.e. N-methyl amide (2), T4-amine O-methyl (7), T4-acetamide (9), N-acyl-T4 (10) and N-formyl-T4 (11) have been synthesized. Each Levothyroxine impurity was characterized based on their spectral data (IR, 1H NMR and Mass). The synthesis and characterisation of the Levothyroxine impurities are discussed
Levothyroxine, Impurity, Synthesis, Characterization, Decarboxylation