One-pot multicomponent reaction: Synthesis, characterization and antibacterial evaluation of novel tri and tetra-substituted imidazoles

Abstract

Using one-pot multicomponent reactions, two new series of imidazoles (4a–o and 6a–d), were synthesized due to their great biological activity. The first series was accomplished by the reaction of O-alkyl vanillins 1a–c, ammonium acetate 2, and benzil derivatives 3a–e in ethanol, while the second series was obtained by reacting O-alkyl vanillins 1a, ammonium acetate 2, benzil 3a, and amino compounds (aniline 5a or amino acids 5b–d) in acetic acid. The in vitro antibacterial activity of the novel synthetic imidazoles was assessed against strains of gram positive bacteria, such as Bacillus cereus and Staphylococcus aureus, and gram negative bacteria, such as Pseudomonas aeruginosa and Escherichia coli. The findings indicated that some of the evaluated items have promising antibacterial agents, especially imidazoles 4d and 4e for (+G) bacteria and imidazoles 4c and 4f for (−G) bacteria.