title: Regioselective monodeprotection of peracetylated carbohydrates.
abstract: This protocol describes the regioselective deprotection of single hydroxyls in peracetylated monosaccharides and disaccharides by enzymatic or chemoenzymatic strategies. The introduction of a one-pot enzymatic step by using immobilized biocatalysts obviates the requirement to carry out tedious workups and time-consuming purifications. By using this straightforward protocol, different per-O-acetylated glycopyranosides (mono- or disaccharides, 1-substituted or glycals) can be transformed into a whole set of differentially monodeprotected 1-alcohols, 3-alcohols, 4-alcohols and 6-alcohols in high yields. These tailor-made glycosyl acceptors can then be used for stereoselective glycosylation for oligosaccharide and glycoderivative synthesis. They have been successfully used as building blocks to synthesize tailor-made di- and trisaccharides involved in the structure of lacto-N-neo-tetraose and precursors of the tumor-associated carbohydrate antigen T and the antitumoral drug peracetylated β-naphtyl-lactosamine. We are able to prepare a purified monoprotected carbohydrate in between 1 and 4 d. With this protocol, the small library of monodeprotected products can be synthesized in 1-2 weeks.
authors.affiliation: Departamento de Biocatálisis, Instituto de Catálisis (CSIC), Madrid, Spain.
authors.forename: Marco
authors.initials: M
authors.lastname: Filice
authors.forename: Jose M
authors.initials: JM
authors.lastname: Guisan
authors.forename: Marco
authors.initials: M
authors.lastname: Terreni
authors.forename: Jose M
authors.initials: JM
authors.lastname: Palomo
mesh_terms: D002241:Carbohydrates / Q000138:chemical synthesis* / Q000737:chemistry; D002621:Chemistry / Q000379:methods; D006031:Glycosylation; D009844:Oligosaccharides / Q000138:chemical synthesis / Q000737:chemistry
chemical_list: D002241:Carbohydrates; D009844:Oligosaccharides