Cyano Derivatives of 7‐Aminoquinoline That Are Highly Emissive in Water: Potential for Sensing Applications.

6‐Cyano‐7‐aminoquinoline (6CN−7AQ) and 3‐cyano‐7‐aminoquinoline (3CN−7AQ) were synthesized and found to exhibit intense emission with quantum yield as high as 63 % and 85 %, respectively, in water. Conversely, their derivatives 6‐cyano‐7‐azidoquinoline (6CN−7N3Q) and 3‐cyano‐7‐azidoquinoline (3CN−7N3Q) show virtually no emission, which makes them suitable to be used as recognition agents in azide reactions based on fluorescence recovery. Moreover, conjugation of 6CN−7AQ with a hydrophobic biomembrane‐penetration peptide PFVYLI renders a nearly non‐emissive 6CN−7AQ‐PFVYLI composite, which can be digested by proteinase K, recovering the highly emissive 6CN−7AQ with ∼200‐fold enhancement. The result provides an effective early confirmation for RT‐qPCR in viral detection. [ABSTRACT FROM AUTHOR]