Enantioseperation of 2-(1H-imidazol-1-yl)-1-(naphthalen-2-yl)ethan-1-ol which is active metabolite of anticonvulsant nafimidone

Nafimidone and nafimidone alcohol, which were synthesized in 1981 and whose anticonvulsant activities were determined, are important anticonvulsant compounds in the structure of (arylalkyl)azole, which reached the stage of clinical human studies but could not pass this stage. In this study, the commercially available chiral stationary phase amylose tris(3,5-dimethyphenylcarbamate) (Chiralpak AD) was used to establish direct enantiomeric separations of nafimidone alcohol which is the methabolite of nafimidone in the normal phase HPLC mode. Investigations were also done into the compositional influences of the mobile phase. When the mobile phase was switched from methanol to n-hexane, the retention times were shortened. The mobile phase of methanol/n-hexane (70:30 v/v) at a flow rate of 0.2 mL/min produced the best results, with an enantiomer resolution of 0.83. Consequently, further chemical and pharmacological research on nafimidone alcohol and its enantiomers can be facilitated by the proposed HPLC approach.