DPH-环糊精纳米管状聚集体的计算机模拟

Molecular Modeling of DPH-Cyclodextrins Nanotube-type Aggregate

1,6-二苯基-1,3,5-己三烯(1,6-diphenyl-1,3,5-hexatriene)(简称DPH)不能与α-环糊精,但可以分别与β-、γ-环糊精通过超分子自组装作用形成纳米管状结构的聚集体.该文采用分子力学和分子动力学模拟对这些聚集体在中性和碱性下条件的理论模型进行了预测,并分析了其主客体间的非键相互作用以及氢键的形成情况.计算结果表明,在碱性条件下,环糊精分子间氢键的消失导致了纳米管状结构的解离;而空腔过小是α-环糊精和DPH之间不能形成纳米管状结构的原因.

By supramolecular self assembling, 1,6 diphenyl 1,3,5 hexatriene( DPH) can form nanotubes with β ,γ cyclodextrins, respectively, but not with α cyclodextrin. Molecular mechanic(MM) calculations and molecular dynamic(MD) simulations were performed to predict the theoretical models of these nanotubes both under neutral and alkaline conditions. The analyses of host guest interactions and hydrogen bonding indicate that the absence of intermolecular hydrogen bond is the main factor which leads to the nanotube′ s breaking down under alkaline condition. Moreover, the calculated results show that the cavity ofα cyclodextrin is too narrow to form nanotubes with DPH.