Behavior of 3-hydrazino-6-aryl-1,2,4-triazin-5-one as a strong nucleophile towards active electrophilic compounds and their antibacterial evaluation

Abstract

The behavior of 3-hydrazino-6-aryl-1,2,4-triazin-5-one towards the active electrophilic compounds in polar and/ or non-polar solvents and various times and temperatures, has been studied. N-[2-(3-(3/5-(4-Nitrophenyl)-5/3-thioxo-1H-1,2,4-triazol-1-yl)-5-oxo-1,2,4-triazin-6-yl)phenyl]pivalamides were obtained from the reaction of N-(2-(3-hydrazineyl-5-oxo-1,2,4-triazin-6-yl)phenyl)-pivalamide with 4-nitrobenzoyl isothiocyanate in THF and/ or EtOH-piperidine respectively. Also, N-(2-(3-hydrazineyl-5-oxo-1,2,4-triazin-6-yl)phenyl)-pivalamide was shown a strong nucleophilic behavior by reaction with N-phenyl-thiourea to produce N-[2-(5-oxo-3-(2-(phenylcarbamothioyl)-hydrazineyl)-1,2,4-triazin-6-yl)phenyl]pivalamide, which upon cyclization with diethyl carbonate produced N-(2-(5-oxo-3-(5-oxo-4-phenyl-3-thioxo-1,2,4-triazolidin-1-yl)- 1,2,4-triazin-6-yl)phenyl)pivalamide. Moreover, N-(2-(3-hydrazineyl-5-oxo-1,2,4-triazin-6-yl)phenyl)pivalamide studied its behavior by reaction with cyanoacetic acid, chloroacetonitrile, and/ or benzoyl carbonitrile to produce N-(2-(3-amino-4,8-dioxo-4H-[1,2,4]triazino[4,3-b][1,2,4]triazin-7-yl)phenyl)pivalamide,N-(2-(4-amino-8-oxo-2H-[1,2,4]triazino[4,3-b][1,2,4]triazin-7-yl)phenyl)pivalamide and N-(2-(4-imino-8-oxo-3-phenyl-4H-[1,2,4] triazino [4,3-b][1,2,4]triazin-7-yl)phenyl)pivalamide. Structure of the products was established upon their elemental analysis and FT-IR, ¹H/ ¹³C NMR, and MS. The new compounds were evaluated as antibacterial agents some Gram-positive and negative bacteria. Some compounds were showed the highest inhibition activity towards Pseudomonas aeruginosa, Bacillus subtilis, Bacillus cereus, and Sarcina lutea bacteria and lowest inhibitory activity against Escherichia coli bacteria.