title: Hydrogen-Bonding-Induced Fluorescence: Water-Soluble and Polarity-Independent Solvatochromic Fluorophores.
abstract: Fluorophores with emission wavelengths that shift depending on their hydrogen-bonding microenvironment in water would be fascinating tools for the study of biological events. Herein we describe the design and synthesis of a series of water-soluble solvatochromic fluorophores, 2,5-bis(oligoethylene glycol)oxybenzaldehydes (8-11) and 2,5-bis(oligoethylene glycol)oxy-1,4-dibenzaldehydes (14-17), based on a push-pull strategy. Unlike typical examples in this class of fluorophores, the fluorescence properties of these compounds are independent of solvent polarity and become fluorescent upon intermolecular hydrogen-bonding, exhibiting high quantum yields (up to ϕ = 0.55) and large Stokes shifts (up to 134 nm). Furthermore, their emission wavelengths change depending on their hydrogen-bonding environment. The described fluorophores provide a starting point for unprecedented applications in the fields of chemical biology and medicinal chemistry.
authors.affiliation: Department of Chemical Engineering, Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Okada
authors.affiliation: Department of Applied Biological Science, Tokyo University of Agriculture and Technology , 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan.
authors.forename: Masae
authors.initials: M
authors.lastname: Sugai
authors.affiliation: Department of Applied Biological Science, Tokyo University of Agriculture and Technology , 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Chiba