title: Synthesis of anomeric sulfonamides and their behaviour under radical-mediated bromination conditions.
abstract: O-Peracetylated methyl 3-(d-glycopyranosylthio)propanoates of beta-d-gluco, and alpha- and beta-d-galacto configurations were oxidized to the corresponding S,S-dioxides (sulfones) by Oxone or MCPBA. Oxidation of the beta-D-gluco derivative with H(2)O(2)/Na(2)WO(4) gave the corresponding S-oxide (sulfoxide). DBU-induced elimination of methyl acrylate from the beta-D-gluco and beta-D-galacto configured S,S-dioxides (sulfones) gave O-peracetylated beta-D-glycopyranosyl-1-C-sulfinates which, on treatment with H(2)NOSO(3)H, furnished the corresponding beta-D-glycopyranosyl-1-C-sulfonamides. Radical-mediated bromination of the protected methyl 3-(beta-D-glycopyranosylthio)propanoate S,S-dioxides gave mixtures of 1-C- and 5-C-bromoglycosyl compounds. Similar brominations of the O-peracetylated beta-D-glycopyranosyl-1-C-sulfonamides resulted in the formation of alpha-D-glycopyranosyl bromides and 1-C- and 5-C-bromoglycosyl sulfonamides. A rationale for these observations was proposed. Methyl 3-(beta-D-glucopyranosylthio)propanoate, its S,S-dioxide, and beta-D-glucopyranosyl-1-C-sulfonamide proved inefficient when tested as inhibitors of rabbit muscle glycogen phosphorylase b.
authors.affiliation: Department of Organic Chemistry, University of Debrecen, PO Box 20, H-4010 Debrecen, Hungary.
authors.forename: Katalin
authors.initials: K
authors.lastname: Czifrák
authors.forename: László
authors.initials: L
authors.lastname: Somsák
mesh_terms: D000818:Animals; D005609:Free Radicals; D024982:Glycogen Phosphorylase, Muscle Form / Q000037:antagonists & inhibitors; D006027:Glycosides / Q000138:chemical synthesis* / Q000737:chemistry; D054879:Halogenation; D015394:Molecular Structure; D011714:Pyrans / Q000737:chemistry*; D011817:Rabbits; D013449:Sulfonamides / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D005609:Free Radicals; D006027:Glycosides; D011714:Pyrans; D013449:Sulfonamides; D024982:Glycogen Phosphorylase, Muscle Form