Synthesis of 4-arylazo-2-(N-pyrazolylcarboxamido)thiophene disperse dyes for dyeing of polyester and their antibacterial evaluation

Abstract

The current article aims to synthesize some new arylazo-thiophenes for dyeing polyester fabrics and screen their antimicrobial activities. The new 4-arylazo-2-( N-pyrazolylcarboxamido)-thiophene dyes 4a–e were prepared by the reaction of 2-acetyl-2-arylazo-thioacetanilide derivative 1 with 2-chloro- N-(3-methyl-1 H-pyrazol-5-yl)acetamide derivative 2. The structures of these prepared analogues were established via Fourier-transform infrared and 1H/13C nuclear magnetic resonance spectra. The synthesized dyestuffs were applied to polyester fabrics after establishing the optimal dyeing conditions at 130 ºC, high pressure, 3% shade, and liquor ratio 20:1 at pH 5. Furthermore, the dyed fabrics obtained under these optimal conditions resulted in proper colorfastness toward washing, rubbing, sublimation and perspiration, and were adequate for light fastness. They showed respectable antibacterial effectiveness against two bacterial strains, Staphylococcus aureus (Gram-positive) and Salmonella typhimurium (Gram-negative) bacteria. The dyed fabric with dye 4d displayed the best antibacterial activities with percentage reduction of 88% and 76% against S. aureus and S. typhimurium bacteria, respectively.

Aspects regarding colour fastness and adsorption studies of a new azo-stilbene dye for acrylic resins

“…The colour of the dye I -WB film under the wet-scrub test slightly changed (See Supplementary Information, Fig. S1 ) according to the colour parameters and to the colour differences (Table 1 ) 35 .…”

Novel germanium-polyamide6 fibers with negative air ions release and far-infrared radiation as well as antibacterial property

“…With the increase in germanium particles added in the fibers and the production of NAIs, part of the E. coli cell membrane’s bioelectric potential or the cell protein structure may be destroyed by the accumulated negative NAIs due to its high oxidation reduction, resulting in the death of E. coli . 20–22 Consequently, most of the E. coli could survive from the NAIs environment and result in a relatively low antibacterial rate.…”

Thiophene‐containing compounds with antimicrobial activity

“…Another set of azo dyes 123 (Figure 13) was obtained from the reaction of 2‐chloro‐ N ‐(3‐methyl‐1 H ‐pyrazol‐5‐yl)acetamide with 3‐oxo‐ N ‐phenyl‐2‐(aryldiazenyl)butanethioamides, which, in turn, were prepared through the coupling of aryldiazonium chlorides with the N , S ‐acetal resulted from acetylacetone and phenyl isothiocyanate. [ 110 ] No evaluation of the antibacterial activity was performed for 3‐arylazo‐2‐phenylaminothiophenes 123 , but the compounds were shown to reduce the bacterial growth on the dyed fabric by 66%–76% in the case of S. typhimurium and by 79%–88% in the case of S. aureus after one wash.…”