X-ray crystal structures of α-cyclodextrin?5-hydroxypentanoic acid, β-cyclodextrin?5-hydroxypentanoic acid, β-cyclodextrin?ε-caprolactone, and β-cyclodextrin?ε-caprolactam inclusion complexes
X-ray crystal structures of α-cyclodextrin?5-hydroxypentanoic acid, β-cyclodextrin?5-hydroxypentanoic acid, β-cyclodextrin?ε-caprolactone, and β-cyclodextrin?ε-caprolactam inclusion complexes
复制标题
α-环糊精·5-羟基戊酸、β-环糊精·5-羟基戊酸、β-环糊精·ε-己内酯和β-环糊精·ε-己内酰胺包合物的X射线晶体结构
DOI：
10.1007/s10847-019-00953-3
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发表时间：
2019
影响因子：
2.3
通讯作者：
Harada Akira
中科院分区：
文献类型：
--
作者：
Osaki Motofumi;Takashima Yoshinori;Kamitori Shigehiro;Yamaguchi Hiroyasu;Harada Akira
以环糊精（CDs）和δ-戊内酯（δVL）水溶液为原料，分别制备了α-环糊精-5 -羟戊酸（αCD-5HPA）和β-环糊精-5 -羟戊酸（βCD-5HPA）包合物。这些溶液在室温下放置一周，得到更适合x射线晶体学的单晶。δVL在α - cd或β - cd存在下发生水解，生成cd和水解产物的包合物。相反，βCD - ε-己内酯（βCD -εCL）和βCD - ε-己内酰胺（βCD -εCLm）的包合物在βCD和εCL/εCLm不水解的水溶液中分别得到。配合物的填充结构表明，αCD- 5hpa形成αCD主体分子的层状结构，βCD- 5hpa、βCD -εCL和βCD -εCLm形成βCD分子的笼状结构。在这些晶体结构中，客体分子通过氢键或疏水相互作用被包含在CD腔中。
Inclusion complexes of α-cyclodextrin–5-hydroxypentanoic acid (αCD-5HPA) and β-cyclodextrin–5-hydroxypentanoic acid (βCD-5HPA) were respectively prepared from aqueous solutions of cyclodextrins (CDs) and δ-valerolactone (δVL). The solutions were allowed to stand at room temperature for 1 week to give single crystals preferable for X-ray crystallography. δVL was found to be hydrolyzed in the presence of αCD or βCD to give the inclusion complexes of CDs and the hydrolysate. On the contrary, inclusion complexes of βCD–ε-caprolactone (βCD–εCL) and βCD–ε-caprolactam (βCD–εCLm) were respectively obtained from the aqueous solution of βCD and εCL/εCLm without hydrolysis. Packing structure of the complexes showed that αCD-5HPA forms a layer-type structure of the αCD host molecules, and that βCD-5HPA, βCD–εCL and βCD–εCLm form cage-type structures of the βCDs molecules. In these crystal structures, the guest molecules are included in the CD cavity through the hydrogen bonds or hydrophobic interactions.