Photoswitchable Spiropyran Dyads for Biological Imaging

Org Lett. 2016 Aug 5;18(15):3666-9. doi: 10.1021/acs.orglett.6b01717. Epub 2016 Jul 26.


The synthesis of a small-molecule dyad consisting of a far-red-emitting silicon rhodamine dye that is covalently linked to a photochromic spironaphthothiopyran unit, which serves as a photoswitchable quencher, is reported. This system can be switched reversibly between the fluorescent and nonfluorescent states using visible light at wavelengths of 405 and 630 nm, respectively, and it works effectively in aqueous solution. Live-cell imaging demonstrates that this dyad has several desirable features, including excellent membrane permeability, fast and reversible modulation of fluorescence by visible light, and good contrast between the bright and dark states.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzopyrans / chemical synthesis
  • Benzopyrans / chemistry*
  • Cell Survival*
  • Fluorescent Dyes / chemical synthesis
  • Fluorescent Dyes / chemistry*
  • Indoles / chemical synthesis
  • Indoles / chemistry*
  • Molecular Structure
  • Nitro Compounds / chemical synthesis
  • Nitro Compounds / chemistry*
  • Optical Imaging / methods*
  • Photochemical Processes
  • Rhodamines / chemical synthesis
  • Rhodamines / chemistry*


  • Benzopyrans
  • Fluorescent Dyes
  • Indoles
  • Nitro Compounds
  • Rhodamines
  • spiropyran