(S)‐Naproxen as a platform to develop chiral derivatizing reagent for reversed‐phase high‐performance liquid chromatographic enantioseparation of analytes having a carbonyl functional group

Abstract

(S)-Naproxen was used to synthesize a chiral reagent, (S)-2-(6-methoxynaphthalen-2-yl)propanehydrazide, by itsreaction with hydrazine hydrate in the presence of dicyclohexylcarbodiimide as coupling agent. The reagent was characterized and its chiral purity was established. It was used as a chiral derivatizing reagent for the synthesis of hydrazone diastereomers, under microwave irradiation, of certain chiral aldehydes and ketones. The respective diastereomers were separated by reversed-phase high-performance liquid chromatography using a binary solvent combination containing trifluoroacetic acid. The diastereomers were detected at 231 nm. The method was validated for accuracy, precision, and limit of detection (LOD). For a series of hydrazones the LOD was found to be in the range 1.62-1.65 pmol/mL.