Abstract
Background: The benzimidazole core structure is an interesting platform for drug discovery since it possess a wide spectrum of pharmacological activities such as antiviral, anti-inflammatory and anticancer. Previously the antiproliferative effect of novel substituted benzimidazole derivative was demonstrated based on the ethyl 1-(2-hydroxyethyl)-2-phenyl-1H-benzo[d]imidazole-5-carboxylate scaffold through the inhibition of sirtuin activity. This work aimed to further explore the previous work for identifying novel fluorescent benzimidazoles which possess anti proliferative activities based on the reported scaffold.
Methods: Compounds were synthesized based on a multistep but facile protocol. Structure of the compounds was elucidated using NMR, FT-IR, LC-MS, elemental analysis and unambiguously confirmed through crystal X-ray diffraction. Molar extinction coefficient of the autofluorescence compounds were determined using UV spectroscopy while cancer cell growth inhibitory activity was carried out using MTS assay. Results: Four novel benzimidazole derivatives were successfully synthesized in this study. All four compounds were found to emit blue fluorescence when light-irradiated with molar extinction coefficient ranging from 21000 to 29000 (mol L-1)-1cm-1. Two of the synthesized compounds showed good anti proliferative activity against four cancer cell lines tested in this study. Conclusion: Four novel benzimidazole derivatives presented in this study were synthesized using multistep protocol starting from 4-fluoro-3-nitrobenzoic acid. Their structures have been elucidated using multiple techniques such as NMR, FT-IR, LC-MS, elemental analysis and X-ray crystallography where possible. They were found to have high autofluorescence and two of them were able to inhibit the growth of cancer cells tested in this study.Keywords: Fluorescence, benzimidazole, anti-cancer, X-ray diffraction, imaging, synthesis.
Graphical Abstract