Thiousugars.X.Studies on Glycosyl N, N-Dialkyldithiocarbamates

Abstract

Several crystalline β-D-glycopyranosyl N, N-dialkyldithiocarbamates (sugar=gluco, galacto, xylo or lacto ; alkyl=methyl or ethyl) were synthesized by reaction of sodium N, N-dialkyl-dithiocarbamates with acetylated α-D-glycopyranosyl bromides and sequential deacetylation with methanolic ammonia or sodium methoxide in methanol. Although the glycosyl dithiocarbamates were stable against chilled alkalis and which is a marked difference from glycosyl xanthates or isothiuronium, easily decomposed with mercury salts to form glycosides under the presence of alcohols or phenols. D-Glucopyranosyl N, N-diethyldithiocarbamates having N, N-diethyldithiocarbamoyl radical [chemical formula] at C6 in acetylated D-glucoses or methyl D-glucopyranosides, along with the didithiocarbamate having two carbamoyls at C1 and C6 in acetylated D-glucopyranose, were also synthesized. Reflux of methyl β-D-glucopyranoside-6-deoxy-6-N, N-diethyldithiocarbamate with sodium methoxide in methanol afforded methyl 6-deoxy-6-thio-β-D-glucopyranoside, isolated as its tetraacetate. The method presented a novel synthetic way of thiosugars.