Iodine and its' interhalogen compounds: Useful reagents in carbohydrate chemistry - X. Adaptation of an NMR signal suppression pulse sequence for theselective removal of benzylic methylene signals of benzyl ether protected carbohydrates

Application of the DPFGSE-TOCSY pulse sequence permits the selective remova l of benzylic signals from the H-1 NMR spectra of benzyl ether-protected gl ycosides. Anomeric proton signals, which have a similar chemical shift, Can be readily re-introduced with the aid of a TOCSY sequence. This approach i s useful in cases where intense spectral overlap does not permit the straig htforward identification of anomeric signals, and hence definition of anome ric configuration or determination of anomeric ratios: The representative a pplication of this pulse sequence to analysis of iodine-promoted thioglycos ide activation is reported. (C) 1999 Elsevier Science Ltd. All rights reser ved.