Sulfenic Acids in the Carbohydrate Field. An Example of Straightforward Access to Novel Multivalent Thiosaccharides

• Published in: Journal of organic chemistry 2005-09, Vol.70 (18), p.7389-7396
• Main Authors: Aversa, Maria C, Barattucci, Anna, Bilardo, Maria Cristina, Bonaccorsi, Paola, Giannetto, Placido, Rollin, Patrick, Tatibouët, Arnaud
• Format: Article
• Language: English
• Subjects: Carbohydrates - chemical synthesis; Carbohydrates with 4, 5, 6, ... C atoms, dissacharides and oligosaccharides; Carbohydrates. Nucleosides and nucleotides; Chemistry; Exact sciences and technology; Organic chemistry; Preparations and properties; Stereoisomerism; Sulfenic Acids - chemical synthesis; Sulfoxides - chemical synthesis
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo0510991

Both anomers of O-protected 1-thio-d-gluco- and -d-mannopyranoses were selected to provide the substrates for developing a smooth and general methodology that gives access to anomeric glycosulfoxides. The behavior of the corresponding β-d-galactopyran derivatives was also investigated. 2-{1-[(2,3,4,6-Tetra-O-acetyl-β-d-glucopyranosyl)sulfinyl](1-methyl)ethyl}malonic acid diethyl esters 4 were thermolyzed in refluxing dichloromethane for generating 2,3,4,6-tetra-O-acetyl-β-d-glucopyranose-1-sulfenic acid (8), in the presence of 2-propynyl β-d-glucopyranoside tetraacetate (32). The syn-addition of transient 8 onto the triple bond of 32 furnished 2-[(2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyl)sulfonyl]-2-propenyl β-d-glucopyranoside tetraacetate (34), after m-CPBA oxidation of the corresponding sulfinyl epimeric mixture 33. This synthetic pathway appears particularly attractive since it represents an example of a mild and versatile approach to thiodisaccharides of foreseeably significant biological behavior. Various carbohydrate-derived sulfenic acids, different in glycosyl moiety and sulfenic function positioning, and various alkynylated carbohydrates can be adopted as combining units in the synthesis of alkene-linked multivalent thiosaccharides.