Synthesis, characterization and X-ray structure of glycosyl-1,2-isoxazoles and glycosyl-1,2-isoxazolines prepared via 1,3-dipolar cycloaddition
作者:Issam Gaamoussi、Ismail Fichtali、Abdeslem Ben Tama、El Mestafa El Hadrami、Donatella Armentano、Giovani De Munno、Miguel Julve、Salah-Eddine Stiriba
DOI:10.1016/j.molstruc.2013.05.043
日期:2013.9
A convenient preparative method of a series of glycosyl-1,2-isoxazoles (6-11) and glycosyl-1,2-isoxazolines (15-20) by a simple and efficient 1,3-dipolar cycloaddition of a series of aryl nitrile oxide, generated in situ from aryl oximes (4-5), with a variety of O-propargyl glycosyles (1-3) or O-allyl glycosyles (12-14) respectively, is reported. The carbohydrate-containing 1,2-isoxazoles and 1,2-isoxazolines compounds were isolated in excellent yields (81-91%) and they were fully characterized by H-1, C-13 NMR and mass spectrometry. The relative stereochemistry of the glycosyl-1,2-isoxazole 10 was confirmed by single crystal X-ray analysis. The molecular structure of 10 confirms the retention of both, the anomeric stereochemistry of the D-fructose as well as the placement of the acetal groups. (c) 2013 Elsevier B.V. All rights reserved.