AFP-CTF urea impurity (Regorafenib impurity)

AFP-CTF urea impurity is a structurally related byproduct of Regorafenib synthesis, characterized by a substituted quinazoline core linked via a urea moiety. The molecule incorporates a 4-chloro-6-(trifluoromethyl)quinazoline scaffold, with a urea bridge connecting the 7-position to a phenyl ring bearing a fluorinated substituent. This impurity arises from incomplete coupling during API synthesis, retaining key aromatic heterocycles and electron-withdrawing fluorine atoms. It serves as a critical HPLC reference standard for quantifying process-derived impurities in Regorafenib formulations.