Selective Recognition of Nucleoside Triphosphates in Water by Tetraphenylethene-Based Tetraimidazolium Cyclophanes†

The design and development of selective recognition and sensing systems for biologically important nucleoside triphosphates (NTPs) have attracted significant attention in recent years, owing to their critical roles in cellular processes. In this study, we report the synthesis of two tetraphenylethene-based tetraimidazolium cyclophanes (1 and 2) through a one-step S_N2 reaction. These cyclophanes are capable of recognizing NTPs by forming stable 1 : 1 host-guest complexes in aqueous solution. Of particular interest, cyclophane 1 demonstrates exceptional selectivity for guanosine triphosphate (GTP), distinguishing it from other nucleoside triphosphates such as ATP, CTP, and UTP. This selective recognition is accompanied by distinct and measurable fluorescence responses, which are significantly enhanced upon binding to GTP, enabling the potential for sensitive detection. This study highlights the potential of tetraphenylethene-based tetraimidazolium cyclophanes as a highly selective and sensitive sensor for GTP, offering new insights into the design of molecular systems for the recognition of biologically relevant nucleotides.