Deconvolution of Complex NMR Spectra in Small Molecules by Multi Frequency Homonuclear Decoupling (MDEC)

Department of Biochemistry, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390-9038, USA.
Journal of the American Chemical Society (Impact Factor: 12.11). 11/2009; 131(44):15994-5. DOI: 10.1021/ja907110e
Source: PubMed

ABSTRACT A new technique to deconvolute complex (1)H NMR spectra of small molecules has been developed that utilizes shape selective pulses to simultaneously decouple multiple protons. A limitation in the assignment of the relative configuration of small molecules is the ability to accurately obtain coupling constants. Other methods such as the E.COSY and the 2D J-resolved are available to obtain complicated coupling constants; the multiple homonuclear decoupling method (MDEC) described is a rapid and simple technique. Three examples of increasing spectral complexity, menthol, cholesteryl acetate and a C(16) fatty acid, demonstrate the utility of the technique. Increasing the experimental utility, the single pulse MDEC experiment can be incorporated in other 1D experiments, such as a 1D-TOCSY to solve specific problems.

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Available from: Ana Paula Espindola, Mar 17, 2015
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