New alpha-selective thermal glycosylation of acetyl-protected 2-acetamido-2-deoxy-beta-D-glucopyranosyl diphenylphosphinate.
This paper describes new alpha-selective thermal glycosylation using acetyl-protected 2-acetamido-2-deoxy-beta-D-glucopyranosyl diphenylphosphinate (4) as a glycosyl donor. When the glycosylation of 4 with 1-hexanol was carried out under various conditions, the conditions using trimethylsilyl trifluoromethanesulfonate as a promoter in nitromethane at reflux temperature were most suitable for the formation of the alpha anomer. The glycosylation of 4 with the other common alcohols gave corresponding alpha-glycosides in relatively high yields under the conditions. When cholesterol, a very steric hindered alcohol, was used as a glycosyl acceptor, alpha-glycoside was also produced predominantly.
Kadokawa
J
J
Department of Materials Science and Engineering, Faculty of Engineering, Yamagata University, Yonezawa, Japan. kadokawa@chem.yz.yamagata-u.ac.jp
Nagaoka
T
T
Ebana
J
J
Tagaya
H
H
Chiba
K
K
D000107:Acetylation; D000117:Acetylglucosamine / Q000031:analogs & derivatives* / Q000737:chemistry; D002236:Carbohydrate Conformation; D006031:Glycosylation; D006358:Hot Temperature; D007202:Indicators and Reagents; D008958:Models, Molecular; D063065:Organophosphonates / Q000737:chemistry*; D010721:Phosphinic Acids; D013816:Thermodynamics
C416841:2-acetamido-3,4,6-tri-O-acetyl-2-deoxyglucopyranosyl diphenylphosphinate; D007202:Indicators and Reagents; D063065:Organophosphonates; D010721:Phosphinic Acids; D000117:Acetylglucosamine