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Binding of carboxylate and trimethylammonium salts to octa-acid and TEMOA deep-cavity cavitands.

ABSTRACT: In participation of the fifth statistical assessment of modeling of proteins and ligands (SAMPL5), the strength of association of six guests (3-8) to two hosts (1 and 2) were measured by 1H NMR and ITC. Each host possessed a unique and well-defined binding pocket, whilst the wide array of amphiphilic guests possessed binding moieties that included: a terminal alkyne, nitro-arene, alkyl halide and cyano-arene groups. Solubilizing head groups for the guests included both positively charged trimethylammonium and negatively charged carboxylate functionality. Measured association constants (K a ) covered five orders of magnitude, ranging from 56 M-1 for guest 6 binding with host 2 up to 7.43 × 106 M-1 for guest 6 binding to host 1.

SUBMITTER: Sullivan MR

PROVIDER: S-EPMC5571645 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Binding of carboxylate and trimethylammonium salts to octa-acid and TEMOA deep-cavity cavitands.

Sullivan Matthew R MR Sokkalingam Punidha P Nguyen Thong T Donahue James P JP Gibb Bruce C BC

Journal of computer-aided molecular design 20160718 1

In participation of the fifth statistical assessment of modeling of proteins and ligands (SAMPL5), the strength of association of six guests (3-8) to two hosts (1 and 2) were measured by <sup>1</sup>H NMR and ITC. Each host possessed a unique and well-defined binding pocket, whilst the wide array of amphiphilic guests possessed binding moieties that included: a terminal alkyne, nitro-arene, alkyl halide and cyano-arene groups. Solubilizing head groups for the guests included both positively char ...[more]

PMID: 27432339

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