3-(Hydrazonoethyl) and 3-(hydrazonobutyl) tetramic acids 6 - 11 are prepared by condensation reaction of N,3-diacetyl and N-acetyl-3-butanoyl tetramic acids, 4 and 5, with a variety of 1,2-(bis)-nucleophiles. The structure elucidation and the tautomeric equilibrium of the novel compounds 6-11 have been studied using 1H and 13C NMR spectroscopy