Synthesis and applications of some new nitrogen-containing heterocyclic azo-disperse dyes bearing quinoline chromophore

A set of five novel nitrogen-containing heterocyclic azo-disperse dyes 8 (a–d) and 10 were synthesized by diazotization of 4-bisaminoquinolines 3, followed by coupling either with rhodanine analogues 6 modified at C-5 position or α-naphthol 9. The chemical structures of 8(a–d) and 10 were proven by the FT-IR, NMR, and mass spectroscopic techniques. Moreover, utilization of these azo dyes in preparing pastes for printing polyester fabric by silk screen traditional printing was achieved. The color strength and fastness properties of the synthesized dyes were also examined and showed moderate-to-excellent resistance to washing, rubbing, and perspiration, as well as fastness to sublimation and light. In addition, the targeted printed samples were screened for their in vitro antibacterial activity against both Gram-positive and Gram-negative bacterial species. The azo compound 8a showed the best antibacterial activity against S. aureus with inhibition zone of 23 mm which is higher than the reference drug Ampicillin (21 mm).