Neva Tania, Carmona Thais, Benito Juan M, Przybylski Cédric, Ortiz Mellet Carmen, Mendicuti Francisco, García Fernández José M
Instituto de Investigaciones Químicas (IIQ), CSIC - University of Sevilla, Sevilla, Spain.
Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Faculty of Chemistry, University of Alcalá, Alcalá de Henares, Madrid, Spain.
Front Chem. 2019 Feb 25;7:72. doi: 10.3389/fchem.2019.00072. eCollection 2019.
The presence of a doubly-linked naphthylene clip at the -2 and -3 positions in the secondary ring of β-cyclodextrin (βCD) derivatives promoted their self-assembly into head-to-head supramolecular dimers in which the aromatic modules act either as cavity extension walls (if the naphthalene moiety is 1,8-disubstituted) or as folding screens that separate the individual βCD units (if 2,3-disubstituted). Dimer architecture is governed by the conformational properties of the monomer constituents, as determined by NMR, fluorescence, circular dichroism, and computational techniques. In a second supramolecular organization level, the topology of the assembly directs host-guest interactions and, reciprocally, guest inclusion impacts the stability of the supramolecular edifice. Thus, inclusion of adamantane carboxylate, a well-known βCD cavity-fitting guest, was found to either preserve the dimeric arrangement, leading to multicomponent species, or elicit dimer disruption. The ensemble of results highlights the potential of the approach to program self-organization and external stimuli responsiveness of CD devices in a controlled manner while keeping full diastereomeric purity.
在β-环糊精(βCD)衍生物二级环的-2和-3位存在双连接萘夹子,促使它们自组装成头对头的超分子二聚体,其中芳香模块要么作为腔延伸壁(如果萘部分是1,8-二取代的),要么作为分隔单个βCD单元的折叠屏(如果是2,3-二取代的)。如通过核磁共振、荧光、圆二色性和计算技术所确定的,二聚体结构由单体成分的构象性质决定。在第二个超分子组织水平上,组装的拓扑结构指导主客体相互作用,反之,客体包合影响超分子结构的稳定性。因此,发现包含金刚烷羧酸盐(一种众所周知的适合βCD腔的客体)要么保持二聚体排列,导致多组分物种,要么引发二聚体破坏。这些结果的整体突出了该方法以可控方式对CD装置进行自组织编程和外部刺激响应的潜力,同时保持完全的非对映体纯度。