Drug synthesis, separation, and identification of a di-stereoisomeric mixture of spiro-oxalidinonic derivatives of sorbinil by high-performance liquid chromatography

Abstract

A straightforward and sensitive method for high-performance liquid chromatography (HPLC) was created in order to separate and identify the di-stereoisomeric mixture of a spiro-oxalidinonic derivative of sorbinil. HPLC was carried out using a C18 reversed-phase column. The mobile phase used in the isocratic elution process was a 70:30 v/v combi¬nation of methanol and acetonitrile flowed at a rate of 2 mL/min. The procedure delivered the best result among the various attempts made. Two peaks were identified on the chromatogram, attributable to the two di-stereoisomers of the mixture analysed. Analogues of sorbinil, a powerful inhibitor of aldose reductase, have been synthesized and further tested on aldose reductase as mixtures of di-stereoisomers, exhibiting an IC50 in the order of the micromolar. The structure of the compounds was checked with nuclear magnetic resonance spectroscopy. The chemical shifts were expressed in ppm scale δ.