Selective 1,2-syn alkynylation of an open chain sugar: the prominent role of zinc chloride addition
摘要:
Depending on the metal, solvent and protective groups, functionalized aldehydes may react through either Felkin or chelated transition states leading to the Felkin Anh product or the 1,2-anti Felkin-Anh product. respectively. Zinc chloride addition proved to be a key aspect in order to favor 1,2-syn nucleophilic attack. (c) 2005 Elsevier Ltd. All rights reserved.
Synthesis of an imidazolo-L-lyxo-piperidinose derivative
摘要:
Imidazolo-L-lyxo-piperidinose 4 was synthesised from the D-galactose derivative 8 by two reaction sequences via removal of a terminal carbon atom stepwise incorporation of an imidazole moiety, and eventually intramolecular S(N)2 reaction to the corresponding piperidine ring. Piperidinose 4 proved to be a poor glycosidase inhibitor. (C) 1998 Elsevier Science Ltd. All rights reserved.
Imidazolo-L-lyxo-piperidinose 4 was synthesised from the D-galactose derivative 8 by two reaction sequences via removal of a terminal carbon atom stepwise incorporation of an imidazole moiety, and eventually intramolecular S(N)2 reaction to the corresponding piperidine ring. Piperidinose 4 proved to be a poor glycosidase inhibitor. (C) 1998 Elsevier Science Ltd. All rights reserved.
Selective 1,2-syn alkynylation of an open chain sugar: the prominent role of zinc chloride addition
作者:Stéphane Guillarme、Arnaud Haudrechy
DOI:10.1016/j.tetlet.2005.03.061
日期:2005.5
Depending on the metal, solvent and protective groups, functionalized aldehydes may react through either Felkin or chelated transition states leading to the Felkin Anh product or the 1,2-anti Felkin-Anh product. respectively. Zinc chloride addition proved to be a key aspect in order to favor 1,2-syn nucleophilic attack. (c) 2005 Elsevier Ltd. All rights reserved.