Synthesis of Novel Dibenzo-18-crown-6- ether-Functionalized Benzimidazoles and its Applications in Colorimetric Recognition to Hg super(2+) and as Antifungal Agents

New crown ether-functionalized benzimidazoles was designed and synthesized via formylation of dibenzo-18-crown-6 followed by condensation with different o-phenylene diamines. The complexation properties of crown ether-functionalized benzimidazoles with various metals (K super(+), Ca super(2+), Ba super(2+), Co super(2+), Hg super(2+)) were examined using UV-vis spectroscopy. Hg super(2+) showed a well-defined peculiar absorption maximum at 366nm exclusively. All these newly synthesized compounds were screened for antifungal activity against Aspergillus niger and Aspergillus oryzae, respectively. New crown ether-functionalized benzimidazoles was synthesized via formylation of dibenzo-18 crown-6 (1) followed by condensation with various o-phenylene diamines (ad) to form corresponding benzimidazole derivatives (3a, 3b, 3c, 3d).