Green Synthesis, Printing Performance, and Antibacterial Activity of Disperse Dyes Incorporating Arylazopyrazolopyrimidines

Abstract

Novel heterocyclic arylazo-disperse dyes containing pyrazolo[1,5-a]pyrimidine structures were prepared via conventional refluxing and microwave heating. Starting from cyanoacetic acid, 4-arylazo-2H-pyrazol-3-ylamine was obtained from a sequence of reactions. This pyrazole intermediate afforded the target arylazo-pyrazolo[1,5-a]pyrimidines and pyrazolo[1,5-a] pyrimidin-7-ones upon cyclization with 3-piperidinylacrylonitrile, ethyl acetoacetate, ethyl(arylhydrazono)acetoacetates, or (arylhydrazono)propanals. The structures of these compounds were confirmed by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, mass spectroscopy, infrared (IR) analysis, and elemental analysis. The disperse colorants produced were applied to printing on polyester fabrics to give satisfactory results. All the synthesized products were tested as antimicrobial agents. Most compounds exhibited relatively strong antibacterial activity against a panel of Gram-positive and Gram-negative bacteria.

A review on synthesis of nitrogen-containing heterocyclic dyes for textile fibers - Part 2: Fused heterocycles

“…Oil crisis in 1970s led to a sharp increment in costs of raw materials for production of dyestuffs. This created a force toward lower cost dyestuffs by enhancing the production procedures and by replacing dyes of low color strength, such as anthraquinone derivatives, with higher color strength dyes, such as heterocyclic dyes [22][23][24][25][26][27][28].…”

Antimicrobial sulphonamide azo dyes

“…They have been considered as xenobiotic substances that are highly recalcitrant against biodegradation processes. They have been applied as acid/base indicators, textile and foodstuff colorants, and biological stains . The first sulphonamide‐based drug was a red azo dye known as Prontosil that was available in 1932.…”

“…In pharmaceutics, the azo bond was employed to protect drugs against undesirable reactions, such as Prontosil treatment and protection against streptococcal infections in mice. Prontosil is inactive in vitro but demonstrates high activity in vivo …”

“…They have been applied as acid/base indicators, textile and foodstuff colorants, and biological stains. [7][8][9] The first sulphonamide-based drug was a red azo dye known as Prontosil that was available in 1932. In pharmaceutics, the azo bond was employed to protect drugs against undesirable reactions, such as Prontosil treatment and protection against streptococcal infections in mice.…”

“…Prontosil is inactive in vitro but demonstrates high activity in vivo. [7][8][9][10] The azo-sulphonamide antimicrobial agents were the first efficient chemotherapeutic drugs that could be applied systemically to treat bacterial infections in humans. There is a category of azo dyestuffs bearing a sulphonamide functional group.…”