NMR Study of New Ligands as Products of Condensation of 2-Pyridinecarboxaldehyde-N-Oxide with Polyamines

New ligands formed as products of the condensation of 2-pyridinecarboxaldehyde-N-oxide with polyamines were prepared and characterised by elemental analysis, 13C NMR spectroscopy and infrared spectroscopy. Schiff base↔saturated heterocyclic ring isomerization was found to be quite common in this system; the five- and/or six-membered saturated heterocyclic rings containing two nitrogen atoms are more stable.