The Schiff base of pyridoxal-5′-phospate with ethylenediamine and ethylamine: Species in solution

Elucidation of intermediates in the transamination reactions has been widely studied on the basis of model reactions between pyridoxal (PL) and pyridoxal 5′-phosphate (PLP) with amines and diamines. H-NMR and UV-visible data [l–4] suggested the presence of carbinolamine and/or geminaldiamine together with Schiff base. The present work deals with a contribution to the study of the reaction mixtures of PLP and ethylenediamine (Etd) and PLP and ethylamine (Et) by electrochemical techniques and UV-visible and fluorescence spectroscopies.