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PubMed · 3943

Structure-basicity and structure-affinity relationships of beta-adrenergic blocking agents.

B Fernández·A J Kaumann
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Abstract

pKa's of fourteen beta-receptor blockers, isoproterenol and norepinephrine, were determined potentiometrically. A Hammett analysis indicated that the influence of ring substituents on the basicity of the amines is attenuated by the ethanolic chain and abolished by the propranoloxy chain of beta-receptor blockers. The effect of ring substituents in phenoxypropranolamines upon affinity for the beta-adrengeric receptors is therefore unrelated to the strength of the bases. Two alterantive hypotheses are fowarded to explain why phenoxypropranolamines have greater affinities for the beta-receptors than phenethanolamines.

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Adrenergic beta-AntagonistsAffinity LabelsChemical PhenomenaChemistryIsoproterenolMolecular ConformationNorepinephrineStructure-Activity RelationshipJournal Article

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B Fernández, A J Kaumann. 1975. Structure-basicity and structure-affinity relationships of beta-adrenergic blocking agents.. https://pubmed.ncbi.nlm.nih.gov/3943/

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