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Rapid Measurement of Heteronuclear Coupling Constants in Complex NMR Spectra.

ABSTRACT: The NMR analysis of fluorine-containing molecules, increasingly widespread due to their importance in pharmaceuticals and biochemistry, poses significant challenges. Severe peak overlap in the proton spectrum often hinders the extraction of critical structural information in the form of heteronuclear scalar coupling constants, which are crucial for determining pharmaceutical properties and biological activity. Here, a new method, IPAP-FESTA, is reported that drastically simplifies measurements of the signs and magnitudes of proton-fluorine couplings. Its usefulness is demonstrated for the structural study of the steroidal drug fluticasone propionate extracted from a commercial formulation and for assessing solvent effects on the conformational equilibrium in a physically inseparable fluorohydrin mixture.

SUBMITTER: Mycroft C

PROVIDER: S-EPMC10510310 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature

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Rapid Measurement of Heteronuclear Coupling Constants in Complex NMR Spectra.

Mycroft Coral C Dal Poggetto Guilherme G Barbosa Thaís M TM Tormena Cláudio F CF Nilsson Mathias M Morris Gareth A GA Castañar Laura L

Journal of the American Chemical Society 20230831 36

The NMR analysis of fluorine-containing molecules, increasingly widespread due to their importance in pharmaceuticals and biochemistry, poses significant challenges. Severe peak overlap in the proton spectrum often hinders the extraction of critical structural information in the form of heteronuclear scalar coupling constants, which are crucial for determining pharmaceutical properties and biological activity. Here, a new method, IPAP-FESTA, is reported that drastically simplifies measurements o ...[more]

PMID: 37650656

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