Synthesis of methyl 6-deoxy-4-O-(sodium sulfonato)-α-L-talopyranoside, its C-4 epimer and both isosteric [4-C-(potassium sulfonatomethyl)] derivatives

The 4-O-sulfuric esters of methyl 6-deoxy--L-talo-and --L-mannopyranoside were prepared. The first ester is a component of the glycopeptidolipid-type cell surface antigens of M. avium. The isosteric isomers (sugar-4-CH 2 -SO 3 Na) of both sulfate esters (sugar-4-O-SO 3 Na) were synthesized using free radical addition reactions between sugar-exomethylene derivatives and either thioacetic acid or NaHSO 3 . The addition products of thioacetic acid were converted into sugar-CH 2 -sulfonic acids by oxidation with oxone. Characteristic 1 H-and 13 C-NMR data are given and discussed.