2-(3,5,6-Trifluoro-2-hydroxy-4-methoxyphenyl)benzoxazole (3) and benzothiazole analogue (4) are prepared by the two-step procedures from the corresponding 2-(pentafluorophenyl)benzazoles. Benzoxazole 3 is applicable to a fluorescent probe sensing magnesium cation, and 4 is suitable for sensing zinc cation. Both fluorophores 3 and 4 are sensitive to the pH change at pH 7-8, resulting in large fluorescence enhancement under basic conditions. Their high sensitivity to pH and selectivity in metal cations are ascribed to the high acidity of the fluorophenol moiety.

中文翻译：

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将2-（3,5,6-三氟-2-羟基-4-甲氧基苯基）苯并恶唑和-苯并噻唑应用于检测pH和金属阳离子的荧光探针。

2-（3,5,6-三氟-2-羟基-4-甲氧基苯基）苯并恶唑（3）和苯并噻唑类似物（4）是通过两步方法由相应的2-（五氟苯基）苯并唑制备的。苯并恶唑3适用于感测镁阳离子的荧光探针，而4适用于感测锌阳离子的荧光探针。荧光团3和4对pH 7-8的pH变化都敏感，因此在碱性条件下荧光增强很大。它们对pH值的高敏感性和在金属阳离子中的选择性归因于氟酚部分的高酸度。