Absorption mode two-dimensional NOE spectroscopy of exchangeable protons in oligonucleotides.

A new NMR method is described for the generation of absorption mode two-dimensional NOE spectra of oligonucleotides in H2O solution. The method yields spectra that are free of baseline distortions with excellent suppression of the intense H2O resonance. The method is demonstrated for a sample of the dodecamer d(CGCGAATTCGCG)2. All exchangeable base protons are identified and a number of new types of NOE connectivities are observed.