Phenyl and trityl 2-O-stilfonyl-1-thio-alpha-D-manno- and beta-D-glucopyranosides were reacted with sodium azide to yield 2-S-phenyl or 2-S-trityl-D-gluco- and D-mannopyranosyl azides, respectively. Usually, both anomers were formed in approximately equal amounts and formation of glycals was also observed in some cases. The product distribution of these reactions depends on the nature of the aglycone, the applied reagent and also on the solvent. These results can be rationalised by the intermediacy of episulfonium as well as oxocarbenium ions. Oxidation of the 2-S-trityl-alpha-D-glycopyranosyl or alpha-D-mannopyranosyl azides by Oxone (R). gave sodium 2-sulfonato-alpha-D-gluco- and alpha-D-mannopyranosyl azides, respectively. (c) 2005 Elsevier Ltd. All rights reserved.
Phenyl and trityl 2-O-stilfonyl-1-thio-alpha-D-manno- and beta-D-glucopyranosides were reacted with sodium azide to yield 2-S-phenyl or 2-S-trityl-D-gluco- and D-mannopyranosyl azides, respectively. Usually, both anomers were formed in approximately equal amounts and formation of glycals was also observed in some cases. The product distribution of these reactions depends on the nature of the aglycone, the applied reagent and also on the solvent. These results can be rationalised by the intermediacy of episulfonium as well as oxocarbenium ions. Oxidation of the 2-S-trityl-alpha-D-glycopyranosyl or alpha-D-mannopyranosyl azides by Oxone (R). gave sodium 2-sulfonato-alpha-D-gluco- and alpha-D-mannopyranosyl azides, respectively. (c) 2005 Elsevier Ltd. All rights reserved.