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Extremely strong tubular stacking of aromatic oligoamide macrocycles.

ABSTRACT: As the third-generation rigid macrocycles evolved from progenitor 1, cyclic aromatic oligoamides 3, with a backbone of reduced constraint, exhibit extremely strong stacking with an astoundingly high affinity (estimated lower limit of K_dimer > 10¹³ M^-1 in CHCl₃), which leads to dispersed tubular stacks that undergo further assembly in solution. Computational study reveals a very large binding energy (-49.77 kcal mol^-1) and indicates highly cooperative local dipole interactions that account for the observed strength and directionality for the stacking of 3. In the solid-state, X-ray diffraction (XRD) confirms that the aggregation of 3 results in well-aligned tubular stacks. The persistent tubular assemblies of 3, with their non-deformable sub-nm pore, are expected to possess many interesting functions. One such function, transmembrane ion transport, is observed for 3.

SUBMITTER: Kline MA

PROVIDER: S-EPMC5424541 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Extremely strong tubular stacking of aromatic oligoamide macrocycles.

Kline Mark A MA Wei Xiaoxi X Horner Ian J IJ Liu Rui R Chen Shuang S Chen Si S Yung Ka Yi KY Yamato Kazuhiro K Cai Zhonghou Z Bright Frank V FV Zeng Xiao Cheng XC Gong Bing B

Chemical science 20140916 1

As the third-generation rigid macrocycles evolved from progenitor 1, cyclic aromatic oligoamides 3, with a backbone of reduced constraint, exhibit extremely strong stacking with an astoundingly high affinity (estimated lower limit of Kdimer > 1013 M-1 in CHCl3), which leads to dispersed tubular stacks that undergo further assembly in solution. Computational study reveals a very large binding energy (-49.77 kcal mol-1) an ...[more]

PMID: 28553464

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