Reaction of (Z)-N-Substituted α,β-Dehydroamino Acids Hydrazides with Oxazolones. Antiradical Activity of Bishydrazides and Bisimidazole-4-ones

The reaction of (Z)-N-substituted α,β-dehydroamino acid hydrazides with 5(4H)-oxazolones was studied. Optimal reaction conditions were found. It was shown that in addition to the main product, bishydrazide, monoimidazolоne hydrazide was also formed. Substituted bishydrazides, N,N-[(2Z,2′Z)-hydrazine-1,2-diyl-bis(1-oxo-3-phenylprop-2-ene-1,2-diyl)]dibenzamides, were converted into the corresponding bisimidazolones—4,4′-di[(Z)-benzylidene]-2,2′-diphenyl-[1,1′-biimidazole]-5,5′(4H,4′H)-diones. Antiradical properties of the synthesized compounds were studied. It was shown that bishydrazides exhibit higher antiradical activity than the corresponding bisimidazolones and monoimidazolone­hydrazide. UV spectra of the synthesized compounds were studied, their molar extinction coefficients at λ_max were determined. Structure of 4,4′-di[(Z)-benzylidene]-2,2′-diphenyl-[1,1′-bisimidazole]-5,5′(4H,4′H)-dione was determined by single crystal X-ray diffraction analysis.