An acid catalyzed reversible ring-opening/ring-closure reaction involving a cyano-rhodamine spirolactam
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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Honglin Li1, Hong Guan, Xinrui Duan
1Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, SC 29208, USA.
Abstract:
Cyanamide was introduced into the rhodamine spirolactam framework to produce a colorless and non-fluorescent compound RBCN. It shows a reversible ring-opening/ring-closure process in response to the solution pH, which exhibits an "ON/OFF" switching in its fluorescence. Different from other rhodamine-type dyes, the ring-open form of RBCN is stable in protic solvents under neutral, near neutral and basic conditions, showing a pink color and very strong fluorescence. We also demonstrated the potential of RBCN in live cell imaging.
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