The effect of chelate cooperativity on the binding of several ditopic anions to two tetrathiourea macrocycles has been analysed in competitive solvent mixtures (H₂O : DMSO 1 : 9 v/v). The semi-flexible receptors bind dicarboxylates with high affinity dependent on the length and flexibility of the guest. Chemical double mutant cycle (DMC) analysis allowed the chelate cooperativity effects to be measured in detail and revealed both positive and negative cooperativity effects which were dependent on guest size, flexibility and spacer interactions between guest and macrocycle. ¹H NMR and crystallographic studies confirmed the macrocycle hosts are adaptable, changing conformation to match their pore size to a selected guest.

中文翻译：

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双位阴离子的构象适应性大环受体：含水介质中螯合物协同性的分析

_{已在竞争性溶剂混合物（H 2} O : DMSO 1 : 9 v/v）中分析了螯合协同性对几种二位阴离子与两个四硫脲大环结合的影响。半柔性受体以高亲和力结合二羧酸盐，具体取决于客体的长度和柔性。化学双突变体循环（DMC）分析可以详细测量螯合协同效应，并揭示正协同效应和负协同效应，这些效应取决于客体大小、灵活性以及客体和大环之间的间隔基相互作用。¹ H NMR 和晶体学研究证实大环主体具有适应性，可以改变构象以使其孔径与选定的客体相匹配。