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Updated: Jun 3, 2026

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Two-dimensional concurrent HMQC-COSY as an approach for small molecule chemical shift assignment and compound
Kaifeng Hu1, William M Westler, John L Markley
1National Magnetic Resonance Facility at Madison, University of Wisconsin-Madison, Madison, WI 53706, USA.
Abstract:
Chemical shift assignment is the first step toward the structure elucidation of natural products and other chemical compounds. We propose here the use of 2D concurrent HMQC-COSY as an experiment for rapid chemical shift assignment of small molecules. This experiment provides well-dispersed (1)H-(13)C peak patterns that are distinctive for different functional groups plus (1)H-(1)H COSY connectivities that serve to identify adjacent groups. The COSY diagonal peaks, which are phased to be absorptive, resemble (1)H-(13)C HMQC cross peaks. We demonstrate the applicability of this experiment for rapidly and unambiguously establishing correlations between different functional groups through the analysis of the spectrum of a metabolite (jasmonic acid) dissolved in CDCl(3). In addition, we show that the experiment can be used to assign spectra of compounds in a mixture of metabolites in D(2)O.
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