Synthesis of 5- and 6-carboxy-X-rhodamines

Org Lett. 2008 Nov 6;10(21):4799-801. doi: 10.1021/ol801904k. Epub 2008 Oct 7.


An efficient route is reported to 5- and 6-carboxy-X-rhodamines (compounds 1 and 2) that contain multiple n-propylene or gamma,gamma-dimethylpropylene groups bridging terminal nitrogen atoms and the central xanthene core. Gram quantities of these dyes are synthesized from inexpensive starting materials. The isolated products are activated by selective transformation of the carboxylic acid group into N-hydroxysuccinimidyl esters in situ and then conjugated with an amino group of a molecule of interest.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Fluorescent Dyes / chemical synthesis
  • Fluorescent Dyes / chemistry
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Rhodamines / chemical synthesis*
  • Rhodamines / chemistry


  • 5-carboxy-X-rhodamine
  • 6-carboxy-X-rhodamine
  • Fluorescent Dyes
  • Rhodamines