O- and N-sulfations of carbohydrates using sulfuryl imidazolium salts.
A series of sulfuryl imidazolium salts (SISs) were prepared and examined as reagents for incorporating trichloroethyl-protected sulfate esters into carbohydrates. The SIS that contained a 1,2-dimethylimidazolium moiety (SIS 9) proved to be a superior sulfating compared to SISs bearing no alkyl groups or bulkier alkyl groups on the imidazolium ring. Difficult O-sulfations that required prolonged reaction times and a large excess of the SIS bearing a 1-methylimidazolium group (SIS 5) were achieved in high yield using less than half the amount of SIS 9 in less time. Certain N-sulfated compounds that were practically inaccessible using SIS 5 were obtained in excellent yield using SIS 9.
Ingram
Laura J
LJ
Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1.
Desoky
Ahmed
A
Ali
Ahmed M
AM
Taylor
Scott D
SD
D002241:Carbohydrates / Q000737:chemistry*; D002625:Chemistry, Organic / Q000379:methods; D004952:Esters; D007093:Imidazoles / Q000737:chemistry*; D008956:Models, Chemical; D015394:Molecular Structure; D009584:Nitrogen / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D012492:Salts / Q000737:chemistry*; D013329:Structure-Activity Relationship; D013431:Sulfates / Q000737:chemistry; D013457:Sulfur Compounds / Q000737:chemistry*
D002241:Carbohydrates; D004952:Esters; D007093:Imidazoles; D012492:Salts; D013431:Sulfates; D013457:Sulfur Compounds; D009584:Nitrogen; D010100:Oxygen