Synthesis, characterization, molecular docking and antimicrobial evaluation of azo coupled – 3, 4- dihydropyrimidine-2(1h)-one derivatives

C Selvinthanuja*, N Kiruthiga, T Prabha, T Sivakumar, N Subramanian

Department of Pharmaceutical Chemistry, Nandha College of Pharmacy, Tamilnadu, India

ABSTRACT

A series of 5-acetyl-4-[(4-substituted phenyl) diazinyl) phenyl]- 6-methyl-3, 4-dihydropyrimidine-2(1H)-one derivatives were synthesised via the coupling reaction between 4- substituted-3, 4- dihydropyrimidine-2(1H)-one and diazonium salt of p-nitro aniline. All the synthesised compounds were structurally elucidated by elemental analysis and IR, 1H NMR and Mass spectral techniques. Investigation of antibacterial and antifungal activity was done on titled compounds using disc diffusion method. Moderate inhibitory activity were displayed by compounds IIa, IId against bacterial strains such as Escherichia coli, Staphylococcus aureus and fungal strains Candida albicans, Aspergillus niger at a concentration range from 400-800μg/ml. Antimicrobial activity of the compounds may be due to the presence of electron donating substituent on phenyl ring attached at fourth position of dihydropyrimidinones. Molecular docking investigation of synthesised compounds performed with bacterial DNA gyrase B which showed that the compound IIa had the binding affinity of -8.3kcal/mol and the compound IId had the binding energy of -9.1 kcal/mol against fungal sterol-14α-demethylase which further supported the biological activity.

Keywords:

Dihydropyrimidinones, Antimicrobial, Disc diffusion, Docking.