Development of new 2-piperidinium-4-styrylcoumarin derivatives with large Stokes shifts as potential fluorescent labels for biomolecules.

A series of novel 2-piperidinium-4-styrylcoumarin derivatives, with large Stokes shifts and high fluorescence quantum yields, were synthesized using an efficient and low-cost synthetic strategy as potential fluorescent labels for biomolecules. Density functional theory and time-dependent density functional theory calculations were performed in order to rationalize the observed photophysical properties.