Applying 2D NMR methods to the structural elucidation of complex natural products

grantor: University of TorontoBy means of a combination of 2D NMR experiments, namely HMQC, HMBC, COSY, TOCSY, NOESY and ROESY, structural determinations and spectral assignments have been completed for a number of natural products and compounds derived from natural products. Examples bearing certain unusual or interesting features are discussed in detail. Three alternative but less widely used techniques are evaluated in terms of their contributions to spectral presentation. HSQC has resolution and sensitivity advantages over HMQC, and coupled HSQC spectra are particularly suitable for the determination of $\sp1$H multiplet patterns, aiding stereochemical assignments. HETCOR and FLOCK provide superior $\sp{13}$C resolution and their sensitivity disadvantages can be minimized by means of a microprobe/microtube combination. Furthermore, linear prediction is a reliable time-saving data processing technique that can enhance the sensitivity of 2D NMR spectra.Ph.D