Dual-mode fluorescence switching of photochromic bisthiazolylcoumarin
Kazushi Suzuki1, Takashi Ubukata, Yasushi Yokoyama
1Department of Advanced Materials Chemistry, Graduate School of Engineering, Yokohama National University, Hodogaya, Yokohama, 240-8501, Japan.
Chemical Communications (Cambridge, England)
|December 3, 2011
Abstract:
Three new photochromic coumarins were synthesized. Fluorescence of the open form of 7-hydroxy-3,4-bisthiazolyl-coumarin increased to 1400% by changing the pH only slightly from 6.05 to 7.58. This was subsequently quenched to 1.5% of the maximum intensity at the UV photostationary state in water-methanol media.
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