New methods for the synthesis of 2-(2,2,2-trichloroethoxy)-(3,4,6-tri-O-acetyl-1,2-dideoxy-α-D-glucopyrano)-[2,1-d]-2-oxazoline and its use for stereo-, chemo- and regioselective glycosylation

• Published in: Carbohydrate research Vol. 520; p. 108633
• Main Authors: Pertel, Sergey S., Seryi, Sergey A., Kakayan, Elena S., Zinin, Alexander I., Kononov, Leonid O.
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 01.10.2022; Elsevier
• Subjects: 2-Alkoxy glyco-[2,1-d]-2-oxazolines; Biochemistry & Molecular Biology; Chemistry; Chemistry, Applied; Chemistry, Organic; Halide ion catalysis; Intermolecular aglycone transfer of thioglycosides; Life Sciences & Biomedicine; Oligosaccharide synthesis; Physical Sciences; Regio-, and chemoselective glycosylation; Science & Technology; SN2-Like mechanism; Stereo; Regio-, and chemoselective glycosylation; SN2-Like mechanism; 2-Alkoxy glyco-[2,1-d]-2-oxazolines; Halide ion catalysis; Oligosaccharide synthesis; Stereo; Intermolecular aglycone transfer of thioglycosides; thioglycosides; 1-d]-2-oxazolines; Regio; 2-Alkoxy glyco-; and chemoselective glycosylation; GLUCOSAMINE; TRISACCHARIDE; AGLYCON TRANSFER; Intermolecular aglycone transfer of
• ISSN: 0008-6215; 1873-426X
• DOI: 10.1016/j.carres.2022.108633

New methods for the synthesis of the title oxazoline 2 from the corresponding 2-deoxy-2-(2,2,2- trichloroethoxycarbonylamino)glucosyl bromide were developed. The target 2-(2,2,2-trichloroethoxy) gluco-[2,1-d]-2-oxazoline 2 can be synthesized under conditions of halide ion catalysis, using triethylamine as a base. The synthesized 2-(2,2,2-trichloroethoxy)-2-oxazoline glycosyl donor was used for stereo-, regio-, and chemoselective glycosylation reactions under extremely mild conditions. The undesirable side reaction of intermolecular aglycone transfer between an ethyl thioglycoside glycosyl acceptor and the 2-(2,2,2-trichloroethoxy)-2-oxazoline glycosyl donor occurred to a relatively small extent. Regio-, and chemoselectivity of the disaccharide synthesis with the oxazoline glycosyl donor depended on the reaction conditions. [Display omitted] •Two methods for the synthesis of alkoxy oxazoline glycosyl donor 2 were developed.•The obtained donor is used for stereo- regio- and chemoselective synthesis of N-Troc protected oligosaccharides.•The intermolecular aglycon transfer occurs to a small extent at glycosylation by donor 2.•Regio- and chemoselectivity depends on conditions of the oligosaccharide synthesis.