SYNTHESIS OF 5-THIO-D-ALLOSE AND THE METHYL 5-THIO-α- AND -β-D-ALLOPYRANOSIDES

Article abstract of DOI:10.1016/0008-6215(86)80033-7

5,6-Anhydro-1,2-O-isopropylidene-3-O-methanesulphonyl-α-D-idofuranose was converted, via the related gluco-5,6-episulphide, into 6-O-acetyl-5-S-acetyl-1,2-O-isopropylidene-3-O-methanesulphonyl-5-thio-α-D-glucofuranose (9).Replacement of the acetyl groups of 9, or the related 3-toluene-p-sulphonate, by an isopropylidene group and saponification of the sulphonate group gave 1,2-O:5,6-S,O-di-isoprpylidene-5-thio-α-D-glucofuranose (2).Epimerisation at C-3 of 2 by an oxidation-reduction sequence gave 1,2-O:5,6-S,O-di-isopropylidene-5-thio-α-D-allofuranose (20) which was hydrolysed to 5-thio-D-allose (1).Methyl 5-thio-α- and -β-D-allopyranoside were obtained from 1 or by methanolysis of 20.Similar hydrolysis or methanolysis of 2 gave 5-thio-D-glucose or methyl 5-thio-α- and -β-D-glucopyranoside, respectively, thus providing a convenient varation on earlier synthetic routes to these compounds. ¹³C N.m.r. data are given for several of these 5-thio-allo and -gluco derivatives.