Regio- and Stereoselective Synthesis of Thioglycosides from 4,5-Diphenyl- and 3,4,5-Triphenylimidazole-2-thione |
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| Authors: | N. Rezki N. Rashed L. F. Awad E. Ramadan S. M. Abdel-Maggeed E. S. H. El Ashry |
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| Affiliation: | 1. Department of Chemistry, Faculty of Science , University of Science and Technology-Mohamed Boudiaf-USTO-MB , Elm'nouar Oran, Algeria;2. Chemistry Department, Faculty of Science , Alexandria University , Alexandria, Egypt;3. Chemistry Department, Faculty of Science , Alexandria University , Alexandria, Egypt;4. International Center for Chemical Sciences , HEJ Research Institute, University of Karachi , Karachi, Pakistan |
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| Abstract: | Six new thioglycosides incorporating the 4,5-diphenyl- and 3,4,5-triphenylimidazole moiety have been successfully synthesized under both conventional and microwave conditions by reaction of the corresponding thiones with aceto-bromosugars in presence of triethylamine as base. Attempted preparation of the bis(glycosyl) derivatives from 4,5-diphenylimidazole-2-thione in the presence of different bases was unsuccessful. Evaluation of the glycosylthioimidazoles as disarmed donors has been investigated using different promoters; NBS/TMSOTf has been found to be an effective promoter for the activation of the anomeric center towards glycosylation reaction. |
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| Keywords: | 4,5-Diphenylimidazole glycosylation microwave irradiation oligosaccharide thioglycosides 3,4,5-triphenylimidazole |
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