Intramolecular 1,8-Hydrogen Atom Transfer Reactions in Disaccharide Systems Containing Furanose Units
作者:Sabrina Guyenne、Elisa I. León、Angeles Martín、Inés Pérez-Martín、Ernesto Suárez
DOI:10.1021/jo301153u
日期:2012.9.7
A previously developed 1,8-hydrogenatomtransfer (HAT) reaction promoted by 6-O-yl alkoxyl radicals between the two pyranose units in Hexp-(1→4)-Hexp disaccharides has been extended to other systems containing at least a furanose ring in their structures. In Penf-(1→3)-Penf (A) and Hexp-(1→3)-Penf (B) disaccharides, the 1,8-HAT reaction and concomitant cyclization to a 1,3,5-trioxocane ring are in
A convergent synthesis of 2′-O-methyl uridine (1) is described. The key steps in our synthesis are: (1) a facile obtention of the 2′-O-methyl sugar synthonusing totally selective and efficient methylation conditions; (2) a stereoselective high-yield condensation with an uracil derivative, yielding the desired β-form.