Cu(OAc)2 as a green promoter for one-pot synthesis of 2-amino-4,6-diarylpyridine- 3-carbonitrile as antibacterial agents

The extensive use of antimicrobial drugs and their resistance against bacterial infections have led to discover new antimicrobial compounds. In this study, we wish to report, one-pot synthesis of 2-amino-3-cyanopyridine derivatives (1a-14a). These compounds were synthesized in the presence of Cu(OAc)2 as a highly effective heterogeneous acid catalyst. Here we evaluated the antimicrobial activities of these compounds against different species of microorganisms including gram positive and gram negative bacteria as well as fungi. Standard antimicrobial methods include disc diffusion and Broth microdilution method according to the protocol of the Clinical and Laboratory Standards Institute (CLSI). Synthesis of 2-amino-3-cyanopyridine derivatives were done via reaction of aromatic aldehydes, acetophenone derivatives, malononitrile and ammonium acetate in the presence of Cu(OAc)2 under reflux condition. The results show compound 2-amino-6-(4-chlorophenyl)-4-phenylnicotinonitrile (10a) had the best antimicrobial efficacy toward C. albicans, E. faecalis, P. aeroginosa and E. coli. In conclusion, comparing the structure and activity of the compounds (10a), this compound with the presence of Cl residue at para-position of phenyl ring improves the antibacterial and antifungal activity. Bull. Chem. Soc. Ethiop. 2020, 34(1), 149-156. DOI: https://dx.doi.org/10.4314/bcse.v34i1.14