Synthesis, Characterization and Antimicrobial Evaluation with DFT Study of New Two-Amino-4-(4-Chlorophenyl) Thiazole Derivatives

Abstract

2-amino-4-(4-chloro phenyl)-1,3-thiazole (1) was synthesized by refluxing thiourea with para-chloro phenacyl bromide in absolute methanol. The condensation of amine compound (1)  with phenylisothiocyanate in the presence of pyridine will  produce 1-(4-(4-chlorophenyl)thiazol-2-yl)-3-phenylthiourea(2), which is  upon treatment with 2,4 dinitrophenyl hydrazine by conventional method, afforded 1- ( 4 - ( 4 – chlorophenyl ) thiazol – 2 – yl ) – 3 - phenylhydrazonamide,N' - ( 2 , 4 -dinitrophenyl) ,(3).The characterization of the titled compounds were performed utilizing FTIR spectroscopy, ¹HNMR and CHNS elemental analysis, and by measurements of  their  physical properties.  The synthesized compounds had been screened for their, in vitro  preliminary antimicrobial activity against three Gram-positive bacteria: (Staph. aureus, Micrococcus luteus and  Bacillus subtilis) and three Gram-negative bacteria : (Pseud.aeruginosa, E.coli and  Proteus mirabilis) ,and two fungal strains(Candida albicans and Candida glabrata ), using a minimum  inhibitory concentration (MIC) of 100 µg\ml of  test compound, by  well diffusion method.

 The derivatives showed moderate antibacterial activity against Gram-positive Staphylococcus aureus and Bacillus subtilis & high antifungal activity against Candida glabrata and Candida albicans. Computational study was performed to calculate some of thermodynamic parameters by using density functional theory (DFT)