Intramolecular nitrone cycloaddition reaction on carbohydrate-based precursors: application in the synthesis of spironucleosides and spirobisnucleosides.
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.
Singha
Kaushik
K
Division of Medicinal Chemistry, Indian Institute of Chemical Biology, Jadavpur, Kolkata 700 032, India.
Roy
Atanu
A
Dutta
Pradeep K
PK
Tripathi
Subhankar
S
Sahabuddin
Sk
S
Achari
Basudeb
B
Mandal
Sukhendu B
SB
D002241:Carbohydrates / Q000737:chemistry*; D009589:Nitrogen Oxides / Q000737:chemistry*; D009705:Nucleosides / Q000737:chemistry*
D002241:Carbohydrates; D009589:Nitrogen Oxides; D009705:Nucleosides; C015388:nitrones