Reaction between glutaric anhydride and N-benzylidenebenzylamine, and further transformations to new substituted piperidin-2-ones

The reaction between glutaric anhydride (1) and N-benzylidenebenzylamine (3) was studied in detail by 1H NMR spectroscopy under different reaction conditions. The major product was (±)-trans-1-benzyl-6-oxo-2-phenylpiperidine-3-carboxylic acid (2), which was converted into new substituted piperidin-2-ones via transformations of the carboxylic group. The final products are expected to possess pharmaceutical activities, and the relevant screenings are in course.