Suppressing one-bond homonuclear 13C,13C scalar couplings in the J-HMBC NMR experiment: application to 13C site-specifically labeled oligosaccharides
2014 (English)In: Magnetic Resonance in Chemistry, ISSN 0749-1581, E-ISSN 1097-458X, Vol. 52, no 3, 82-86 p.Article in journal (Refereed) Published
Site-specific C-13 isotope labeling is a useful approach that allows for the measurement of homonuclear C-13,C-13 coupling constants. For three site-specifically labeled oligosaccharides, it is demonstrated that using the J-HMBC experiment for measuring heteronuclear long-range coupling constants is problematical for the carbons adjacent to the spin label. By incorporating either a selective inversion pulse or a constant-time element in the pulse sequence, the interference from one-bond C-13,C-13 scalar couplings is suppressed, allowing the coupling constants of interest to be measured without complications. Experimental spectra are compared with spectra of a nonlabeled compound as well as with simulated spectra. The work extends the use of the J-HMBC experiments to site-specifically labeled molecules, thereby increasing the number of coupling constants that can be obtained from a single preparation of a molecule.
Place, publisher, year, edition, pages
2014. Vol. 52, no 3, 82-86 p.
NMR, 1H, 13C, J-HMBC, oligosaccharide, heteronuclear long-range coupling constants, site-specific labeling
Chemical Sciences Physical Chemistry Organic Chemistry
IdentifiersURN: urn:nbn:se:su:diva-101733DOI: 10.1002/mrc.4038ISI: 000330951600003OAI: oai:DiVA.org:su-101733DiVA: diva2:705666
FunderSwedish Research CouncilKnut and Alice Wallenberg Foundation