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Linear free energy relationships reveal structural changes in hydrogen-bonded host-guest interactions.

ABSTRACT: Hydrogen bond strength in host-guest systems is modulated by many factors including preorganization, steric effects, and electronic effects. To investigate how electronic effects impact barbiturate binding in bifurcated Hamilton receptors, a library of receptors with differing electronic substituents was synthesized and (1)H NMR titrations were performed with diethyl barbital. The Hammett plot revealed a clear break between the different electronic substituents suggesting a change in binding conformation. The titration data were complimented with computational studies confirming the change in structure.

SUBMITTER: McGrath JM

PROVIDER: S-EPMC4260963 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Linear free energy relationships reveal structural changes in hydrogen-bonded host-guest interactions.

McGrath Jacqueline M JM Pluth Michael D MD

The Journal of organic chemistry 20141120 23

Hydrogen bond strength in host-guest systems is modulated by many factors including preorganization, steric effects, and electronic effects. To investigate how electronic effects impact barbiturate binding in bifurcated Hamilton receptors, a library of receptors with differing electronic substituents was synthesized and (1)H NMR titrations were performed with diethyl barbital. The Hammett plot revealed a clear break between the different electronic substituents suggesting a change in binding con ...[more]

PMID: 25412431

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