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Molecular Encapsulation of Histamine H?-Receptor Antagonists by Cucurbit[7]Uril: An Experimental and Computational Study.

ABSTRACT: The histamine H?-receptor antagonists cimetidine, famotidine and nizatidine are individually encapsulated by macrocyclic cucurbit[7]uril (CB[7]), with binding affinities of 6.57 (±0.19) × 10³ M(-1), 1.30 (±0.27) × 10? M(-1) and 1.05 (±0.33) × 10? M(-1), respectively. These 1:1 host-guest inclusion complexes have been experimentally examined by ¹H-NMR, UV-visible spectroscopic titrations (including Job plots), electrospray ionization mass spectrometry (ESI-MS), and isothermal titration calorimetry (ITC), as well as theoretically by molecular dynamics (MD) computation. This study may provide important insights on the supramolecular formulation of H?-receptor antagonist drugs for potentially enhanced stability and controlled release based on different binding strengths of these host-guest complexes.

SUBMITTER: Yin H

PROVIDER: S-EPMC6274153 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Molecular Encapsulation of Histamine H₂-Receptor Antagonists by Cucurbit[7]Uril: An Experimental and Computational Study.

Yin Hang H Wang Runmiao R Wan Jianbo J Zheng Ying Y Ouyang Defang D Wang Ruibing R

Molecules (Basel, Switzerland) 20160906 9

The histamine H₂-receptor antagonists cimetidine, famotidine and nizatidine are individually encapsulated by macrocyclic cucurbit[7]uril (CB[7]), with binding affinities of 6.57 (±0.19) × 10³ M(-1), 1.30 (±0.27) × 10⁴ M(-1) and 1.05 (±0.33) × 10⁵ M(-1), respectively. These 1:1 host-guest inclusion complexes have been experimentally examined by ¹H-NMR, UV-visible spectroscopic titrations (including Job plots), electrospray ionization mass spectrometry (ESI-MS), and isothermal titration calorimetr ...[more]

PMID: 27608003

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