Synthesis and photophysical properties of a bichromophoric system hosting a disaccharide spacer

Org Biomol Chem. 2017 Oct 4;15(38):8211-8217. doi: 10.1039/c7ob01764b.

Abstract

The synthesis of an efficient energy donor-acceptor system is reported, together with its photophysical properties. The bichromophoric species has been conceived to show potentialities for biological applications since a biocompatible disaccharide spacer, constituted of d-galactose and d-glucose derivatives, was used in compound 12 to connect two BODIPY units with different absorption/emission properties. The luminescence spectrum in acetonitrile of 12 shows an intense fluorescence band with a maximum at about 770 nm that is almost identical to that of the lowest-energy BODIPY, regardless of the excitation wavelength used. The quantum yield is 0.2 with an excited state lifetime of 2.5 ns. Excitation and ultrafast transient absorption spectroscopy demonstrates that a very efficient energy transfer takes place in 12 from the highest-energy lying BODIPY subunit to the lowest-energy emissive BODIPY moiety, with a time constant of about 31 ps. Noteworthily, the emission of 12 falls in the near infrared window, suitable for potential biological applications.

MeSH terms

  • Boron Compounds / chemistry*
  • Disaccharides / chemistry*
  • Fluorescent Dyes / chemical synthesis*
  • Molecular Structure
  • Photochemistry

Substances

  • 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene
  • Boron Compounds
  • Disaccharides
  • Fluorescent Dyes