- A Molecular Chameleon with Fluorescein and Rhodamine Spectroscopic Behaviors
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A new class of fluorescein/rhodamine hybrids with two spirolactone rings was reported to exhibit dual-output fluorescent behaviors independently. Isolation and characterization for two diastereomers, trans-RhOH and cis-RhOH, have been made and their X-ray crystal structures determined. In a basic environment, the spirolactone ring on the hydroxyl side will be opened to give a fluorescein-like optical output with the lowest absorptions at 485 and 530 nm emission. On the other hand, a rhodamine-like optical output, i.e., 528 nm absorption and 575 nm emission, will be switched on by a H+ or a Hg2+ ion, attributed to the spirolactone ring opening on the amino side. In a methanol-buffer system with different pH values, the corresponding pKa values for the hydroxyl and amino groups were determined as 5.7 and 2.3, respectively. Selective Hg2+-sensing properties have also been discussed, and log Ks values of about 3.60 and 3.73 were determined. Confocal microscopic images of Caenorhabditis elegans incubated with RhOH were found to show enhanced fluorescent intensity with a Hg2+ ion, demonstrating the potential application of RhOH for in vivo biological imaging.
- Li, Ling,Wang, Chunyan,Wu, Jianjian,Tse, Yu Chung,Cai, Yue-Peng,Wong, Keith Man-Chung
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p. 205 - 213
(2016/01/15)
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- A laterally π-expanded fluorone dye as an efficient near infrared fluorophore
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The synthesis and photophysical properties of new dibenzo[b,i]fluorone dye frameworks (BX and FBX) are described. Both BX and FBX display near-infrared sharp absorption and emission upon the addition of base due to the achievement of efficient π-conjugation based on the small bond alternation strategy.
- Sezukuri, Kyohei,Suzuki, Mitsuharu,Hayashi, Hironobu,Kuzuhara, Daiki,Aratani, Naoki,Yamada, Hiroko
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supporting information
p. 4872 - 4875
(2016/04/10)
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- Fluorescent probe
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A fluorescent probe which is represented by the following formula (I): (wherein, R1 and R2 represent hydrogen atom, or a substituent for trapping proton, a metal ion, or an active oxygen species, or the like; R3 represents
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Page/Page column 13
(2009/05/29)
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- FLUORESCENT XANTHENES AND WHITE LIGHT FLUOROPHORES
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Xanthene compounds are disclosed having fluorescence at multiple wavelengths. Also disclosed are methods for their synthesis and use. Some of the compounds fluoresce at three wavelengths, emitting white light. Uses include the imaging of biological tissues, illumination, and display technologies. Many of the compounds have large Stokes shifts, and are resistant to photobleaching. The fluorescence may be readily distinguished from that of endogenous fluorophores, and from that of most existing, commercially-available fluorescent probes. The compounds are well suited for use in "multiplexing" techniques. They exhibit clear isosbestic and isoemissive points, and have broad absorption and emission ranges.
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Page/Page column 13; Fig. 14
(2010/11/29)
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- A convenient preparation of xanthene dyes
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A facile synthetic route utilizing readily available reagents affords a series of regioisomerically pure xanthene dye derivatives. Advantages include relatively mild conditions and good to excellent yields. Nonpolar, highly crystalline intermediates are i
- Yang, Youjun,Escobedo, Jorge O.,Wong, Alexander,Schowalter, Corin M.,Touchy, Michael C.,Jiao, Lijuan,Crowe, William E.,Fronczek, Frank R.,Strongin, Robert M.
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p. 6907 - 6912
(2007/10/03)
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