l-Valine derived benzimidazole based bis-urea in enantioselective fluorescence sensing of L-tartrate

l-Valine derived benzimidazole based bis-urea 1 has been designed and synthesized. The bis-urea 1 is found to act as enantioselective chemosensor for tartrate. The sensor shows greater fluorescence response for L-tartrate in DMSO. The enantiomeric fluorescence difference ratio (ef) has been determined to be 2.46. In comparison, less steric receptor 2 exhibits a marginal preference for d-tartrate over the l-tartrate in DMSO and validates the steric role of the substituents around the benzimidazole motif in 1 toward enantioselective recognition of tartrate.