Novel acid/base-controllable fluorescent host-guest system among 1, 2 and 3 was successfully constructed, in which cryptand host 1 could reversibly interchange between two different recognition sites 2 and 3 by regulating on guest molecule 3, as evidenced by ¹H NMR and fluorescence spectroscopy. This research provides a viable and alternative procedure to construct cryptand-based stimuli-responsive fluorescent molecular switches by external stimuli acting on guest molecules.

中文翻译：

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荧光宿主系统的可逆切换：通过调节客体分子在两个不同的识别位点之间进行密码互换

新颖酸/间碱可控荧光主-客体系统1，2和3构建成功，其中穴状主机1可以在两个不同的识别位点之间可逆地交换2和3通过调节上客体分子3，通过证明¹ 1 H NMR和荧光光谱。这项研究提供了可行的和可替代的程序，通过作用于客体分子上的外部刺激来构建基于穴体的刺激响应性荧光分子开关。