The Role of C2-Substituents in the Imidazolone Ring in the Degradation of GFP Chromophore Derivatives

Abstract

The role of C2-substituents in the imidazolone ring of borated GFP chromophore derivatives (4-(2-(difluoroboryl)benzylidene)-1H-imidazol-5(4H)-ones) in the degradation process was studied. It was found that the nature of this substituent hardly affected their photostability, whereas their sensitivity toward nucleophilic reagents decreased with an increase in size and donating properties of the substituent. The results supported an assumption that the introduction of C2 substituents was not a rate-limiting step of the degradation process of these derivatives and complex C2 substituents were not effective tools for the improvement of their stability.