Separation of new antidiabetic agent,N-(trans-4-isopropylcyclohexylcarbonyl)-d-phenylalanine and three related compounds by RP-HPLC

A high-performance liquid chromatographic method is proposed for the simultaneous separation of two pairs of isomers:N-(trans-4-isopropylcyclohexylcarbonyl)-d-phenylalanine, (Nateglinide) andN-(cis-4-isopropylcyclohexylcarbonyl)-d-phenylalanine,trans-4-isopropylcyclohexane-carboxylic acid andcis-4-isopropyl-cyclohexanecarboxylic acid using a C18 column. The mobile phase is a ternary mixture of acetonitrile-methanol-0.1 M ammonium dihydrogen phosphate buffer, pH 3.0 (5:2:4 v/v/v) and UV detection at 210 nm. Precision, linearity, limit of detection and recovery were also evaluated for each compound. Satisfactory results were obtained.