Synthesis of quinoline dicarboxylic esters as biocompatible fluorescent tags

J Org Chem. 2012 Sep 21;77(18):8294-302. doi: 10.1021/jo301652j. Epub 2012 Sep 12.

Abstract

A series of dicarboxylic quinoline derivatives bearing electron-releasing or -withdrawing substituents have been synthesized using mono- or/and biphasic methodologies. By controlling the regioselectivity of addition into our electrophilic intermediate, we also characterized by which mechanism the Doebner-Miller cyclization step occurred. As anticipated, electron-releasing substituents induce a red shift of the low-energy absorption allowing excitation in the visible region. In addition, by playing on the strength and position of the electron-releasing substituents, chromophore having interesting fluorescent properties such as large Stoke shifts, good fluorescent quantum yields, emission in the visible green-yellow region and reasonable two-photon absorption in the NIR region have been obtained. These small-size fluorophores, which can be made water-soluble and have been shown to be non-toxic, can be hetero- and/or polyfunctionalized and thus represent promising key units for fluorescence-based physiological experiments with low background interactions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Absorption
  • Dicarboxylic Acids / chemical synthesis*
  • Dicarboxylic Acids / chemistry
  • Electrons
  • Esters
  • Fluorescent Dyes / chemical synthesis*
  • Fluorescent Dyes / chemistry
  • Molecular Structure
  • Quinolines / chemical synthesis*
  • Quinolines / chemistry
  • Spectrometry, Fluorescence

Substances

  • Dicarboxylic Acids
  • Esters
  • Fluorescent Dyes
  • Quinolines