Cationic Au(I) complexes (2, 5 and 8) supported by N-heterocyclic carbene, silylene and germylene ligands were prepared and their potential as catalysts in glycosidation chemistry has been evaluated. Insights into the mechanism are provided using DFT studies. Practical application of them as catalysts was achieved by the synthesis of the branched pentamannan core of the HIV-gp120 envelope under mild
AuBr3 mediated glycosidations: synthesis of tetrasaccharide motif of the Leishmania donovani lipophosphoglycan
作者:Gopalsamy Sureshkumar、Srinivas Hotha
DOI:10.1007/s10719-012-9400-7
日期:2012.5
Tetrasaccharide cap present in lipophosphoglycan of the Leishmania donovani responsible for visceral Leishmaniaisis is synthesized as a fully protected propargyl glycoside. AuBr3 mediated selective glycosylation of propargyl 1,2-orthoester in the presence of propargyl glycoside is employed as a key step to obtain propargyl containing oligomers. Further, propargyl tetrasaccharide is connected with a long chain hydrocarbon containing azidothiol functionality situated at two terminal ends via ‘click’ reaction.