A C4N4 Diaminopyrimidine Fluorophore

• Published in: Chemistry : a European journal Vol. 25; no. 17; pp. 4299 - 4304
• Main Authors: Noda, Hidetoshi, Asada, Yasuko, Maruyama, Tatsuro, Takizawa, Naoki, Noda, Nobuo N., Shibasaki, Masakatsu, Kumagai, Naoya
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 21.03.2019; Wiley Subscription Services, Inc
• Subjects: Absorption; Absorptivity; Amino groups; Aromatic compounds; Autophagy; bioconjugation; Chemical composition; Chemical compounds; Chemistry; Chemistry, Multidisciplinary; Fluorescence; live-cell imaging; Medical imaging; Organic materials; Phagocytosis; Physical Sciences; Proteins; pyrimidine; Science & Technology; Stokes shift; bioconjugation; Stokes shift; FLUORESCENT; fluorescence; AGGREGATION-INDUCED EMISSION; LIVE-CELL; live-cell imaging; CHEMISTRY; pyrimidine; GENERAL-METHOD
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201900467

A new scaffold for producing efficient organic fluorescent materials was identified: 2,5‐diamino‐4,6‐diarylpyrimidine featuring a C4N4 elemental composition. Single‐step installation of two aryl groups at the 4,6‐positions of the pyrimidine core delivered fluorescent organic materials in a modular fashion. A range of fluorescent compounds with distinct absorption/emission properties was readily accessed by changing the aromatic attachments. A generally high absorption coefficient and quantum yield were observed, including C4N4 derivatives that could fluoresce even in the solid state. The two amino groups at the 2,5‐positions of the pyrimidine were essential for intense fluorescence with a large Stokes shift, which was corroborated by structural relaxation to a p‐iminoquinone‐like structure in the excited state. Besides live‐cell imaging capabilities, fluorescent labeling of a protein involved in autophagy elucidated a new protein–protein interaction, supporting potential utility in bioimaging applications. A new scaffold for producing efficient organic fluorescent materials was identified: 2,5‐diamino‐4,6‐pyrimidine featuring a C4N4 elemental composition (see figure). Single‐step installation of two aryl groups at the 4,6‐positions of the pyrimidine core delivered fluorescent organic materials in a modular fashion.