Glycosidation of 3,4,6-Tri-<i>O</i>-Benzyl-2-Ethenyl-D-Glucal – A Route to 2-<i>C</i>-(β-Methyl)Methylene Glycosides
作者:Ben-Ami Feit、Idil Kasuto Kelson、Anke Gerull、Sarah Abramson、Richard R. Schmidt
DOI:10.1080/07328300008544109
日期:2000.1
Monosaccharidic and disaccharidic 2-C-(beta-methyl)methylene glycosides were synthesized by an electrophilic conjugate addition reaction of ROH-type compounds in the presence of Ph3+PH Br- to 2-ethenyl-3,4,6-tri-O-benzyl-D-glucal 1, functioning as a model glycosyl donor. This 2-vinyl glucal derivative represents a series of 2-vinyl, and 2-butadienyl glycals, prepared by Wittig-type methylenation of pyranosidic conjugated enals, derived from glucal, galactal and lactal. The exo-(beta-methyl)methylene group paves the way for further chemical transformations.