Synthesis, dyeing performance on polyester fiber and antimicrobial studies of some novel pyrazolotriazine and pyrazolyl pyrazolone azo dyes

Abstract 5-Amino-4-heterylazo-3-phenyl-1 H -pyrazoles ( 2a – d ) were diazotized and coupled with malononitrile to give pyrazoloazo malononitrile which by heating in glacial acetic acid gave novel pyrazolo[5,1- c ][1,2,4]triazine dyes ( 3a – d ). Also, some diazopyrazolyl pyrazolone dyes ( 4a – h ) were synthesized by diazotization of 2a – d and coupled with some pyrazolone derivatives. The structure of the synthesized dyes was determined by elemental analysis and spectral data. All the synthesized compounds were applied as disperse dyes and their dyeing performance on polyester fabric was studied. The fastness and colorimetric properties were measured. The results revealed that the monoazo dyes have good fastness and good to moderate affinity to polyester fabric than diazo dyes. In addition, the synthesized dyes were screened for their antimicrobial activities against Staphylococcus aureus , Pseudomonas aeruginosa (Gram positive), Bacillus subtitles , Escherichia coli (Gram negative) and Candida albicans , Aspergillus niger (Fungi). The results revealed that most of the prepared dyes have high antibacterial activity.