Determination of the (R)- and (S)-enantiomers of salsolinol and N-methylsalsolinol by use of a chiral high-performance liquid chromatographic column

A new method for the quantitative determination of the enantiomers of salsolinol and N-methylsalsolinol, biologically important alkaloids, is reported. The enantiomers were completely separated without derivatization, using a cyclodextrin-modified silica gel column with an HPLC-electrochemical detection system. The HPLC conditions were examined for the best resolution. The method was sensitive enough to detect salsolinol and N-methylsalsolinol at a concentration of less than 0.1 pmol per injection. In the product of the Pictet-Spengler reaction of acetaldehyde with dopamine or epinine, almost equimolar (R)- and (S)-enantiomers of salsolinol and N-methylsalsolinol were detected. Preliminary results indicate that the (R)-enantiomer of both isoquinoline derivatives predominate in the human brain.