191721-03-6Relevant articles and documents
Regio- and stereoselective synthesis of 3- and 5-(C-glycosyl)-4- nitroisoxazolidines by nitrone-nitroalkene [3+2] cycloaddition reactions
Borrachero, Pastora,Cabrera, Francisca,Dianez, Ma. Jesus,Estrada, Ma. Dolores,Gomez-Guillen, Manuel,Lopez-Castro, Amparo,Moreno, Jose Ma.,De Paz, Jose L.,Perez-Garrido, Simeon
, p. 77 - 98 (1999)
Cycloaddition reactions of nitrones, including sugar nitrones, with nitroalkenes, including sugar nitroolefins, led with complete regioselectivity and stereospecificity to 4,5-trans-4-nitroisoxazolidines in 51-78% global yields. The endo/exo stereoselectivity depends on the type of sugar derivative used. As expected, the best π-diastereofacial selectivity was observed when both partners were sugar derivatives. Isomerisation of the first formed diastereomers by the action of silica gel was observed in some cases. Absolute configurations for two crystalline products were assigned by X-ray diffraction methods.