Synthesis, crystal structure and thermal properties of N'-[(E)-3,5-di-tert-butyl-2-hy-droxy-benzyl-idene]-2-hy-droxy-benzohydrazide ethanol quatersolvate.

In the structure of the title compound, 4C22H28N2O3·C2H6O, mol-ecules composed of an acyl-hydrazone segment bridging a 3,5-di-tert-butyl-phenol unit and a 2-hy-droxy-phenol unit form columnar quartet channels along the a-axis, within which disordered ethanol solvent mol-ecules reside in two inversion-centre-related positions. Inter-molecular hydrogen bonds assemble the channels between the columnar mol-ecules through the hosted ethanol mol-ecule, complemented by weaker van der Waals-type inter-actions. These weak van der Waals inter-actions also hold the columns together. Additionally, the title compound demonstrated notable thermal stability at temperatures of up to 251°C. The sharp melting point peak observed in the DSC confirmed its crystalline structure.