title: Direct 2,3-O-isopropylidenation of α-D-mannopyranosides and the preparation of 3,6-branched mannose trisaccharides.
abstract: A highly efficient, regioselective method for the direct 2,3-O-isopropylidenation of α-D-mannopyranosides is reported. Treatment of various α-D-mannopyranosides with 0.12 equiv of the TsOH·H2O and 2-methoxypropene at 70 °C gave 2,3-O-isopropylidene-α-D-mannopyranosides directly in 80%~90% yields. Based on this method, a 3,6-branched α-D-mannosyl trisaccharide was prepared in 50.4% total yield using p-nitrophenyl 2,3-O-isopropylidene-α-D-mannopyranoside as the starting material.
authors.affiliation: Department of Applied Chemistry, China Agricultural University, Beijing 100193, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Jiang
authors.affiliation: Department of Applied Chemistry, China Agricultural University, Beijing 100193, China.
authors.forename: Guanghui
authors.initials: G
authors.lastname: Zong
authors.affiliation: Department of Applied Chemistry, China Agricultural University, Beijing 100193, China.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Liang
authors.affiliation: Department of Applied Chemistry, China Agricultural University, Beijing 100193, China.
authors.forename: Shuhui
authors.initials: S
authors.lastname: Jin
authors.affiliation: Department of Applied Chemistry, China Agricultural University, Beijing 100193, China. zhangjianjun@cau.edu.cn.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Applied Chemistry, China Agricultural University, Beijing 100193, China.
authors.forename: Daoquan
authors.initials: D
authors.lastname: Wang
mesh_terms: D002240:Carbohydrate Sequence; D060326:Chemistry Techniques, Synthetic; D008358:Mannose / Q000737:chemistry*; D008738:Methyl Ethers / Q000737:chemistry; D015394:Molecular Structure; D014312:Trisaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D014753:Vinyl Compounds / Q000737:chemistry
chemical_list: D008738:Methyl Ethers; D014312:Trisaccharides; D014753:Vinyl Compounds; C534882:2-methoxypropene; D008358:Mannose