title: Intramolecular nitrone cycloaddition reaction on carbohydrate-based precursors: application in the synthesis of spironucleosides and spirobisnucleosides.
abstract: A simple synthesis of chiral spironucleosides and spirobisnucleosides is described. Intramolecular 1,3-dipolar nitrone cycloaddition reaction of d-glucose-derived precursors having olefin at C-3 and nitrone at C-5, C-1, or C-2 (in nor-series) furnished bisisoxazolidinospirocycles 4-7, 11, and 12 in good yields. Reductive ring opening of the isoxazolidine moieties in 4-6 followed by construction of a nucleoside base upon the generated amino groups smoothly yielded spirobisnucleosides 17 and 18 and spironucleosides 20 and 21.
authors.affiliation: Division of Medicinal Chemistry, Indian Institute of Chemical Biology, Jadavpur, Kolkata 700 032, India.
authors.forename: Kaushik
authors.initials: K
authors.lastname: Singha
authors.forename: Atanu
authors.initials: A
authors.lastname: Roy
authors.forename: Pradeep K
authors.initials: PK
authors.lastname: Dutta
authors.forename: Subhankar
authors.initials: S
authors.lastname: Tripathi
authors.forename: Sk
authors.initials: S
authors.lastname: Sahabuddin
authors.forename: Basudeb
authors.initials: B
authors.lastname: Achari
authors.forename: Sukhendu B
authors.initials: SB
authors.lastname: Mandal
mesh_terms: D002241:Carbohydrates / Q000737:chemistry*; D009589:Nitrogen Oxides / Q000737:chemistry*; D009705:Nucleosides / Q000737:chemistry*
chemical_list: D002241:Carbohydrates; D009589:Nitrogen Oxides; D009705:Nucleosides; C015388:nitrones