Three acyl hydrazones N'-[(2-hydroxynaphthalen-1-yl)methylene]-2-phenylacetohydrazide (I), N'-[(2-hydroxynaphthalen-1-yl)methylene]-2-(4-hydroxyphenyl)acetohydrazide hydrate (II) and N'-[(2-hydroxynaphthalen-1-yl)methylene]-2-(2-methoxyphenyl)acetohydrazide hydrate (III) were synthesized and then characterized by elemental anal. and single-crystal X-ray diffraction.The crystallog. data indicated that both compounds II and III crystallized in the monoclinic crystal lattice, space group C2/c, while compound I crystallized in the orthorhombic space group Pbca.The thermal decomposition processes of the three hydrazones were studied by thermogravimetry.The thermal decomposition temperatures of compounds I, II and III were 318.23, 319.04 and 323.01°C, resp.Meanwhile, the apparent activation energies for thermal decomposition for compounds I, II and III were 115.90, 145.18 and 129.38 kJ·mol-1, resp., calculated according to the Kissinger and Ozawa equations.The interactions of compounds I-III with calf thymus (CT)-DNA were evaluated by microcalorimetry.The results indicated these interactions were homogeneous endothermic processes with non-identical interaction time (1.00-50.0 min) and interaction enthalpies (0.47-15.50 kJ·mol-1).The interaction enthalpies of compounds I and II were higher than those of their precursors, while the interaction enthalpy of compound III was lower than that of its precursor.
