EFFICIENT SYNTHESIS OF A NEW AMINOAZASUGAR AND DIHYDROXYPROLINES FROMAN ENDOCYCLIC ENECARBAMATE

A novel procedure for the synthesis of s-2,3-(2-aminomethyl)-cis-3,4-d ihydroxypyrrolidine (a new aminoazasugar) and cis-2,3- and trans-2,3-c is-3,4-dihydroxyprolines is presented. Starting from the known endocyc lic enecarbamate 1-carbobenzyloxy-2-pyrroline, the above compounds wer e efficiently synthesized in 6 or 7 steps in good overall yields. In t he key step, enzyloxy)-cis-3,4-diacetyloxy-2-methoxypyrrolidine underw ent Lewis acid promoted cyanation, presumably via the corresponding N- acyliminium ion.