Natural-abundance 15N-13C correlation spectra of vitamin B-12

Two-dimensional nitrogen-carbon NMR correlation spectra have been derived by a new reconstruction technique based on standard two-dimensional HMQC and HMBC spectra, and operating with natural N-15 and C-13 isotopic abundances. Compared with conventional three-dimensional spectroscopy in which N-15 and C-13 spins must be present in the same molecule, the reconstruction method offers two orders of magnitude improvement in sensitivity. Vitamin B-12 serves as an illustrative example. Copyright (c) 2007 John Wiley & Sons, Ltd.