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通过２-氨基吡啶与β环糊精醛３在甲醇水溶液中反应合成了一种新型含吡啶基β－环糊精衍生物４，并采用荧光光谱滴定法测定了它与几种脂肪氨基酸在磷酸盐缓冲溶液（ｐＨ＝ ７．２， ０． １ｍｏｌ· Ｌ－１）中于 ２５℃时形成超分子配合物的稳定常数．化学计量法结果显示，化合物４与氨基酸形成了１：１的超分子配合物．圆二色谱研究表明，在溶液中化合物４的取代基浅包结进入自身环糊精空腔．修饰环糊精中的吡啶基作为一种光谱探针，不仅可以识别氨基酸分子的尺寸或形状，而且还可以识别Ｌ／Ｄ－型手性对映体之间的差异．与单－［６－（１－吡啶基）－６－脱氧］－β－环糊精５相比，化合物４对氨基酸的对映体选择性发生翻转，其中对Ｄ／Ｌ－丝氨酸给出最高的对映体选择性达５．４．从主－客体间几何互补、诱导楔合以及几种弱相互作用力的协同效应，讨论了环糊精衍生物选择性结合氨基酸形成超分子配合物的稳定性．
A novel pyridyl β-cyclodextrin derivative 4 was synthesized by the reaction of 2-aminopyridine and β-cyclodextrin 3 in aqueous methanol. The fluorescence intensity of this compound with several aliphatic amino acids in phosphoric acid Salt buffer solution (pH = 7.2, 0.1 mol · L-1) at 25 ℃ formed supramolecular complex stability constants. The results of stoichiometry showed that compound 4 formed a 1: 1 supramolecular complex with amino acids. Circular dichroism studies showed that the substituents of compound 4 in solution were lightly entrapped into the cyclodextrin cavity itself. The pyridyl group in cyclodextrins is modified as a spectroscopic probe to not only identify the size or shape of the amino acid molecule but also to identify the differences between the L / D-type chiral enantiomers. Compound 4 reversed the enantioselectivity of amino acids compared to mono- [6- (1-pyridyl) -6-deoxy] -β-cyclodextrin 5, with the highest for D / L-serine Enantiomer selectivity of 5.4. From the synergetic effect between host-guest geometric complementation, induced wedging and several weak interaction forces, the stability of cyclodextrin derivatives to selectively bind amino acids to form supramolecular complexes was discussed.