Synthesis, characterization and biological studies of some novel 3-fluorosalicylaldehyde based amine derivatives

Abstract

A series of biologically important substituted 3-fluorosalicylaldehyde derivatives (1a-h) with various primary amines were synthesized by using ionic liquid (1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) as an efficient catalyst. A new series of Schiff base derivatives (1a-h) were synthesized and characterized by IR, NMR ((1)H, (13)C, (1)H-(1)H COSY and HSQC), mass spectra and elemental analysis. Further crystal structure of compound 1a was evaluated by single crystal X-ray diffraction techniques. All the synthesized compounds were screened for in vitro antimicrobial activity against a panel of selected bacterial and fungal strains using Streptomycin and Amphotericin B as standards. Most of the synthesized compounds demonstrated moderate effects on both antibacterial and antifungal activities at minimum inhibitory concentrations (MIC's).

Keywords: 1D-NMR; 2D-NMR spectroscopy; Antimicrobial activity; Ionic liquid; Single crystal-XRD.