Synthesis of Benzimidazole derivatives containing Schiff base exhibiting antiurease activities

In this study some novel Schiff bases derivatives of benzimidazole containing thiophene ring were designed and synthesized by using various aldehydes. Seven different aromatic aldehydes with various side groups were used for synthesized. 1H-NMR, 13C-NMR spectra and LC-MS were used to identify all of the compounds. All synthesized compounds anti urease activities were calculated according to phenol-hypochlorite method by Weatherburn. The results indicated that all compounds have anti urease activity between 12.70±0.11 µg/mL and 14.00±0.08 µg/mL IC50 values. Especially the compound N'-[(1E)-2-furylmethylene]-2-[5,6-dimethyl-2-(2-thienylmethyl)-1H-benzimidazol-1-yl]acetohydrazide (5g) has very close IC50 value (12.70±0.11 µg/mL) to thiourea (12.60±0.10 µg/mL) that is the standard inhibitor. 5g bearing furan ring at the N-3 position on the benzimidazole nucleus has the smallest volume of side group than others.