Synthesis and characterization of coumarin thiazole derivative 2-(2-amino-1,3-thiazol-4-yl)-3H-benzo[f]chromen-3-one with anti-microbial activity and its potential application in antimicrobial polyurethane coating

• Biocide additives in paint are used to prevent bacterial and fungal growth.
• The 2-(2-amino-1,3-thiazol-4-yl)-3H-benzo[f]chromen-3-one was synthesized.
• And then characterized following incorporation into a polyurethane coating.
• The results obtained suggest that it imparts a very good anti-microbial effect.
• The molecular modeling study revealed that it fulfills Lipinski's rule of five.

Coumarin, thiazole and their respective derivative products are some of the oldest and most commonly known class of nitrogen and sulphur containing compounds. In recent years there has been considerable interest in this coumarin–thiazole derivatives, which have been reported to exhibit significant biological activity and are widely used as pharmaceuticals. They are capable of imparting anti-microbial activity properties when incorporated into polymers and polymer composites. In this research, coumarin–thiazole derivative 2-(2-amino-1,3-thiazol-4-yl)-3H benzo[f]chromen-3-one (compound III), was prepared and its structure was confirmed by means of its spectra data. It was also screened for its anti-microbial activity against eight different micro-organisms when physically incorporated into a polyurethane varnish formula. Experimental coatings were manufactured on a laboratory scale and applied by means of a brush on both glass and steel panels. The results of the biological activity indicated that the polyurethane varnishes containing the 2-(2-amino-1,3-thiazol-4-yl)-3H-benzo[f]chromen-3-one (compound III) derivative, exhibit a very good antimicrobial effect. The molecular modeling study revealed that it is biologically safe, it is active and it fulfills Lipinski's rule of five. The physical and mechanical resistances of the polyurethane varnish formulations were also studied to evaluate any drawbacks associated with the addition of the derivative. The studies indicate that the physical incorporation of compound III actually enhances slightly both the physical and mechanical properties.

The coumarin thiazole derivative 2-(2-amino-1,3-thiazol-4-yl)-3H-benzo[f]chromen-3-one was obtained. Its structure was confirmed by its spectra data and in addition was screened for its anti-microbial activity when physically incorporated into a polyurethane varnish formula. The anti-microbial activity against the eight different micro-organisms that it was exposed to, suggest that it enhances the biocide performance. The molecular modeling study undertaken revealed that the derivative fulfills Lipinski's rule of five. (A) Coumarin thiazole derivative structure. (B) Antimicrobial activity of blank and blended polyurethane with biocide against eight different microorganismsFigure optionsDownload as PowerPoint slide