Deoxy-sugars. Part XXVI. The cleavage of sulphonic esters with lithium aluminium hydride

Abstract

Cleavage with lithium aluminium hydride of the 2-toluene-~-sulphonates and 2-methanesulphonates of methyl p-r,-arabinoside and its 3 : 4-0-isopropylidene derivative has been studied. Both esters of the latter sugar undergo direct cleavage and methyl 3 : 4-O-isopropylidene-P-~-arabinoside is regenerated. Methyl 2-O-methanesulphonyl(or 2-O-toluene-p-sulphony1)p-L-arabinoside gave methyl p-L-arabinoside, 2 : 3-anhydro-P-~-riboside, 2-deoxy-P-~-riboside, and 3-deoxy-P-~-xyloside (-riboside). These results are compared with those obtained by the hydrogenolysis of sulphonic esters of sugarswith sodiuni amalgam (Vargha, Puskh, and Kagy,