Abstract: It has been a continuous interest in measurement of homonuclear scalar coupling constants using two-dimensional NMR spectroscopy because large chemical shift dispersions can efficiently increase spectral resolution. Numerous methods have been developed using homo-and hetero-nuclear correlation and successfully used for a variety of samples. Here we demonstrate an alternative approach based on maximum-quantum correlation NMR spectroscopy (MAXY NMR). The new method combines the advantages of two-dimensional chemical shift dispersion and the spectral editing feature of the MAXY approach and results in separated correlations of CH, CH₂, and CH₃ groups in a single experiment with enhanced chemical shift resolution. The method had been tested on a middle-sized molecule, dexamethasone, and a tridecapeptide, neurotensin.

Key words: ¹H NMR, MAXY, Coupling constants, Neurotensin, Peptide, Dexamethasone