Synthesis of anomeric sulfonamides and their behaviour under radical-mediated bromination conditions
摘要:
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 (R) or MCPBA. Oxidation of the beta-D-gluco derivative with H2O2/Na2WO4 gave the corresponding S-oxide (sulfoxide). DBU-induced elimination of methyl acrylate from the P-D-gluco and P-D-galacto configured SS-dioxides (sulfones) gave O-peracetylated beta-D-glycopyranosyl-1-C-sulfinates which, on treatment with H2NOSO3H, 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 U-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. (C) 2008 Elsevier Ltd. All rights reserved.
Synthesis of anomeric sulfonamides and their behaviour under radical-mediated bromination conditions
作者:Katalin Czifrák、László Somsák
DOI:10.1016/j.carres.2008.11.002
日期:2009.2
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 (R) or MCPBA. Oxidation of the beta-D-gluco derivative with H2O2/Na2WO4 gave the corresponding S-oxide (sulfoxide). DBU-induced elimination of methyl acrylate from the P-D-gluco and P-D-galacto configured SS-dioxides (sulfones) gave O-peracetylated beta-D-glycopyranosyl-1-C-sulfinates which, on treatment with H2NOSO3H, 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 U-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. (C) 2008 Elsevier Ltd. All rights reserved.