Blonanserin chloro impurity

Blonanserin chloro impurity is a structurally related degradation byproduct arising from oxidative chlorination of the parent antipsychotic Blonanserin. It features a 3-chloro-substituted benzisoxazole core linked to a piperazine ring with a 2-methoxyphenyl moiety, differing from Blonanserin by an additional chloro group at the 3-position of the benzisoxazole ring. This impurity retains the piperazine-benzisoxazole-phenyl scaffold but exhibits altered electronic properties due to chloro substitution, impacting chromatographic resolution. It serves as a critical HPLC reference standard for quantifying process-related impurities in Blonanserin formulations.