An efficient and catalytic protocol for highly stereoselective construction ofβ-mannopyranosylation has been developed.Glycosylation of 2,6-lactone-bridged mannopyranosyl ortho-hexynylbenzoate with various acceptors ...An efficient and catalytic protocol for highly stereoselective construction ofβ-mannopyranosylation has been developed.Glycosylation of 2,6-lactone-bridged mannopyranosyl ortho-hexynylbenzoate with various acceptors proceeded smoothly in the presence of 5%Hg(Ⅱ)at room temperature,resulting in the correspondingβ-mannosides in high yield and exclusiveβ-stereoselectivity.展开更多
Understanding how the diversity of glycolipids,including how their chemical structures and composition affect their biological functions,is a remarkable fundamental challenge.In this work,we employed a rare monosaccha...Understanding how the diversity of glycolipids,including how their chemical structures and composition affect their biological functions,is a remarkable fundamental challenge.In this work,we employed a rare monosaccharide,3-deoxy-Dmanno-2-octulosonic acid(Kdo)to build a simple and biomimetic model to understand the diversity of glycolipids from the viewpoint of supramolecular chemistry.Kdo was chosen not only because its unusual 8-carbon acidic carbohydrate backbone is very different from common hexoses,but also because of its key structural role in lipopolysaccharides and prevalence in bacteria,plant life,and algae.It was found that although both of the two Kdo-lipids S-Kdo and Kdo-S derived from the same carbohydrate backbone and gave bicelles as their self-assembled morphology,experimental results revealed that the self-assembly showed pathway complexity.Bicelle is the thermodynamic product of S-Kdo,while for Kdo-S,the bicelle is only a kinetically trapped state,which finally transforms to a ribbon.Molecular simulation clearly revealed the different packing of Kdo-lipids in the bicelles with different contribution from hydrogen bonds and electrostatic interactions.展开更多
基金supported by National Natural Science Foundation of China(Nos.21472119,22107061)the Science and Technology Program of Shaanxi Province,China(No.2018ZDXM-GY-152)。
文摘An efficient and catalytic protocol for highly stereoselective construction ofβ-mannopyranosylation has been developed.Glycosylation of 2,6-lactone-bridged mannopyranosyl ortho-hexynylbenzoate with various acceptors proceeded smoothly in the presence of 5%Hg(Ⅱ)at room temperature,resulting in the correspondingβ-mannosides in high yield and exclusiveβ-stereoselectivity.
基金the financial support from the National Natural Science Foundation of China(grant nos.51721002,21861132012,91956127,and 21975047)NSFC/China(grant nos.21674114 and 91956127)for financial supportsupported by the Shanghai Municipal Science and Technology Major Project(grant no.2018SHZDZX01)and ZJ Lab.
文摘Understanding how the diversity of glycolipids,including how their chemical structures and composition affect their biological functions,is a remarkable fundamental challenge.In this work,we employed a rare monosaccharide,3-deoxy-Dmanno-2-octulosonic acid(Kdo)to build a simple and biomimetic model to understand the diversity of glycolipids from the viewpoint of supramolecular chemistry.Kdo was chosen not only because its unusual 8-carbon acidic carbohydrate backbone is very different from common hexoses,but also because of its key structural role in lipopolysaccharides and prevalence in bacteria,plant life,and algae.It was found that although both of the two Kdo-lipids S-Kdo and Kdo-S derived from the same carbohydrate backbone and gave bicelles as their self-assembled morphology,experimental results revealed that the self-assembly showed pathway complexity.Bicelle is the thermodynamic product of S-Kdo,while for Kdo-S,the bicelle is only a kinetically trapped state,which finally transforms to a ribbon.Molecular simulation clearly revealed the different packing of Kdo-lipids in the bicelles with different contribution from hydrogen bonds and electrostatic interactions.
