Hadamard 1D 1H TOCSY and its application to oligosaccharides

Abstract

Replacement of a series of N consecutive one-site selective excitation NMR experiments by N simultaneous N-site excitations with phases of component pulses varied according to the N × N Hadamard matrix offers a sensitivity improvement of the order of √N (for N = 2, 4, 8, . . . ) [R. Freeman, Spin Choreography, pp. 177-183. Spektrum, Oxford (1996)]. Here this principle was extended to one-dimensional (1D) 1H TOCSY experiments, in the absence and presence of heteronuclear decoupling. The ID 1H Hadamard TOCSY technique was applied to selected oligosaccharides, representing a class of biomolecules for which multiple 1D TOCSY experiments are the mainstay in 1H NMR spectral assignment and structural characterization. © 1997 John Wiley & Sons, Ltd.