Synthesis and biological activity of heterylamides of aroylpyruvic acids and 5-arylpyrazole-3-carboxylic acids

Substituted amides and hydrazides of acylpyruvic acids. Part 11. Synthesis and biological activity of 4-aryl-2-hydroxy-4-oxo-2-butenoic acid n-(1,3-thiazol-2-yl)amides

“…From this we infer that amides Ia -Iz in the solid state occur in the X-enol form, which does not contradict the existing notions about the structure of compounds in this series [9,17].…”

“…The proposed structures were confirmed by the results of spectroscopic measurements with reference to the known thiazolylamides of acylpyruvic acids [3,9,17]. The biological activity of the newly synthesized compounds Ia -Iz was compared to that of their structural analogs: benzoylpyruvic acid thiazolylamide (Ia¢) [17] and pivaloylpyruvic acid thiazolylamide (III) [3,9,23].…”

“…The biological activity of the newly synthesized compounds Ia -Iz was compared to that of their structural analogs: benzoylpyruvic acid thiazolylamide (Ia¢) [17] and pivaloylpyruvic acid thiazolylamide (III) [3,9,23].…”

Synthesis of 4-Aryl-2-hydroxy-4-oxo-N-{4-[(1,3-thiazol-2-yl)- sulfamoyl]phenyl}but-2-eneamides

“…In the IR spectra of compounds 1-7 there were absorption bands of stretching vibrations of amino (3450-3200 cm - According to 1 H NMR data compounds 1-7 exist in two tautomeric forms A and B. Thus, in the 1 H NMR spectra of compounds 1-5 a weak signal appeared at 4.53-4.59 ppm characteristic of the β-methylene group of the diketone form.…”

“…The reaction the most frequently used for the preparation of amides is the treatment of 5-aryl-2,3-dihydrofurane-2,3-dione with amines in anhydrous benzene, dioxane, toluene or other solvents [1,7,8], which has a number of drawbacks [9,10]. We have developed a simple and more suitable method of the synthesis of N-arylamides of aroylpyruvic acids where it is not necessary to use anhydrous solvents and toxic reagents [10][11][12].…”