title: Precise measurement of long-range heteronuclear coupling constants by a novel broadband proton-proton-decoupled CPMG-HSQMBC method.
abstract: A broadband proton-proton-decoupled CPMG-HSQMBC method for the precise and direct measurement of long-range heteronuclear coupling constants is presented. The Zangger-Sterk-based homodecoupling scheme reported herein efficiently removes unwanted proton-proton splittings from the heteronuclear multiplets, so that the desired heteronuclear couplings can be determined simply by measuring frequency differences between singlet maxima in the resulting spectra. The proposed pseudo-1D/2D pulse sequences were tested on nucleotides, a metal complex incorporating P heterocycles, and diglycosyl (di)selenides, as well as on other carbohydrate derivatives, for the extraction of (n) J((1) H,(31) P), (n) J((1) H,(77) Se), and (n) J((1) H,(13) C) values, respectively.
authors.affiliation: Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem tér 1, 4032 Debrecen (Hungary).
authors.forename: István
authors.initials: I
authors.lastname: Timári
authors.forename: Tünde Z
authors.initials: TZ
authors.lastname: Illyés
authors.forename: Ralph W
authors.initials: RW
authors.lastname: Adams
authors.forename: Mathias
authors.initials: M
authors.lastname: Nilsson
authors.forename: László
authors.initials: L
authors.lastname: Szilágyi
authors.forename: Gareth A
authors.initials: GA
authors.lastname: Morris
authors.forename: Katalin E
authors.initials: KE
authors.lastname: Kövér
keywords: HSQMBC; NMR spectroscopy; heteronuclear coupling constants; proton-proton decoupling; structure elucidation