Physicochemical investigation and fluorescence quenching of biologically active pyrrole-containing push-pull chromophore by Ag nanoparticles

Abstract

An efficient, one pot, multicomponent synthesis of 4-[(1-methyl-1H-pyrrol-2-yl)methylidene]-2-phenyl-1,3-oxazol-5(4H)-one (MPMO) from 1-methylpyrrole-2-carbaldehyde, hippuric acid (N-Benzoylglycine), and NaOAc in acetic anhydride has been developed. The solvatochromic properties viz. Stokes shift, excitation coefficient, and fluorescence quantum yield for MPMO has been explored by recording its absorption and emission spectra in solvents of varied polarities. When the solvent polarity varies from less-polar (n-hexane) to highly polar (dimethyl sulfoxide, DMSO), the emission and absorption maximum show red shift. Interaction of MPMO with the CTAB and SDS could be used for the determination their critical micellar concentration (CMC). Further, fluorescence quenching of MPMO with colloidal silver nanoparticles (AgNPs) was observed and the Stern–Volmer quenching rate constant (Ksv) in ethanol and ethane-1,2-diol (glycol), was determined to be 1.43 × 108M − 1 and 1.32 × 108M − 1 respectively. The antibacterial activity of MPMO was evaluated against Gram-positive and Gram-negative bacterial strains and results showed the compound MPMO good antibacterial agent against Gram-negative bacteria.