Vilazidone cyano ester impurity

Vilazidone cyano ester impurity is a structurally related synthetic byproduct arising from the esterification pathway during vilazidone production. It features a cyano-substituted aromatic heterocycle linked via an ester bond to a piperazine moiety, with the cyano group occupying the 4-position of the pyridine ring. This impurity results from partial oxidation of the parent drug’s methylene bridge, introducing a nitrile functionality. It serves as an HPLC reference standard for quantifying process-related impurities in vilazidone active pharmaceutical ingredients.