Carbohydrate-derived iminium salt organocatalysts for the asymmetric epoxidation of alkenes
作者:Philip C. Bulman Page、Yohan Chan、John Liddle、Mark R.J. Elsegood
DOI:10.1016/j.tet.2014.07.052
日期:2014.10
A new family of carbohydrate-based dihydroisoquinolinium salts has been prepared and tested for potential as asymmetric catalysts for the epoxidation of unfunctionalized alkene substrates, providing up to 57% ee in the product epoxides.
Trimethylsilylnitrate−Trimethylsilyl Azide: A Novel Reagent System for the Synthesis of 2-Deoxyglycosyl Azides from Glycals. Application in the Synthesis of 2-Deoxy-β-<i>N</i>-glycopeptides
作者:B. Gopal Reddy、K. P. Madhusudanan、Yashwant D. Vankar
DOI:10.1021/jo0354948
日期:2004.4.1
1-azido 2-deoxy sugars in one step in fair to good yields. Galactals offer higher stereoselectivities than do the glucals. Reduction of the azide group with Ph3P−H2O to amino functionality followed by coupling with amino acids leads to the synthesis of novel 2-deoxy-β-N-glycopeptides irrespective of the geometry of initial azido sugars. Using this protocol, a new γ-sugar amino acid derivative is also procured