Synthesis and Evaluation of New Anti-microbial Additives Based on Pyrazole and Triazole Derivatives Incorporated Physically into Polyurethane Varnish for Surface Coating and into Printing Ink Paste

PYRAZOLE, triazole, pyramidine, phenylsulfone and their derivatives are some of the oldest and best known class of nitrogen and sulphur containing compounds. In the recent years there has been considerable interest in phenylsulfonyl, pyrazolo and phenylsulfonyl triazolo derivatives due to the presence of the important pharmacophore groups. In this particular research, certain compounds as 5-(methylthio)-6-(phenylsulfonyl)-3-(p-tolyldiazenyl)- pyrazolo [1,5-a] pyrimidine-2,7-diamine (compound II), 3-((4-metho-xyphenyl) diazenyl) -5-(methylthio) -6-(phenylsulfonyl) pyrazolo [1,5-a]pyrimidine-2,7-diamine (compound III) and 5-(methylthio)-6-(phenylsulfonyl) [1,2,4]triazolo[1,5-a] pyrimidin-7-amine (compound IV) were prepared and their structure was confirmed by spectral data and also screened for their antimicrobial activity against six different micro-organisms when physically incorporated into polyurethane varnish formula and printing ink paste. Experimental coatings were manufactured on a laboratory scale and applied by brush on glass and steel panels. Results of the biological activity indicated that polyurethane varnishes and printing ink paste containing compounds II, III and IV exhibit a very good antimicrobial effect. The physical and mechanical resistances of the polyurethane varnish formulations were also studied to evaluate any drawbacks associated with this addition. The studies revealed that the physical incorporation of compounds II, III and IV marginally enhances both physical and mechanical properties.