Stereoselective Microwave-assisted Synthesis of 2-Deoxy-2-fluoro-α-glycosides

Identifier:  TFG:1663

Handle: https://hdl.handle.net/20.500.11797/TFG1663

Authors:  Barros de Souza, Allisson

Abstract:
2-Deoxy-2-fluoro-α-glycosides are compounds of increasing interest in the biochemical and medical research. Therefore, finding new methods to obtain mainly one of the two diastereoisomers is important. The present project has as main objective to synthetize selectively α-anomer (axial) by glycosylation reaction. In this reaction, the nucleophile (glycosyl donor) reacts with an electrophile (glycosyl acceptor) thought a nucleophilic substitution. In order to obtain mainly α-anomer, it is known that in a pyranose sugar, the formation of the axial diastereoisomer is more favoured due to the anomeric effect. Therefore, the glycosylation reaction was performed under thermodynamic control (heating by microwaves) to favour the formation of the most stable diastereoisomer (α-anomer). The characterization was carried out by NMR techniques (1H, 19F, 13C, NOE, COSY, HSQC and HMBC). Once optimized the glycosylation, scope study was performed using different carbohydrates.