The synthesis of some methyl 6-deoxy-2-O-p-tolylsulphonyl-D-xylo-hexofuranosid-5-ulose derivatives and their reactions with bases

Methyl 6-deoxy-2,3-di-O-p-tolylsulphonyl-β-D-xylo-hexofuranosid-5-ulose (8) was prepared from 6 deoxy-1,2:3,5-di-O-methylene-α-D-xylo-hex-5-enofuranose (5). On treatment with bases, compound 8 readily loses p-toluenesulphonic acid to give a furan derivative (9); with 1,5-diazabicyclo[5.4.0]undec-5-ene, it also affrorded a compound which gave a mass spectrum consistent with its being 3-methoxy-6-oxo-2-oxabicyclo[2.2.1]heptan-7-ol (10). The analogue (13) of compound 8 having a methyl group in place of the ester function at C-3 did not react when treated with the heterocyclic base.