Ethers Anhydro-sugars

Oxlranes.- The synthesis of the racemic 2,3-anhydro-4-deoxy-DL-erythro-pentopyranosides (16), 3,4-anhydro-DL-arabinopyranoslde (17) and 2,3-anhydro-DL-erythrofuranosides (i8) by epoxidation (peroxy- 

The polymerization behaviour of 5 6-anhydro-l,2-0-lsopropylidene-a-D-allo- and gluco-furanoses, with and without 3- -t enzyl ether groups, has been examined.Both enantiomers of 3 -epoxytetra-hydropyran [1.e., (21) and (22)] are hydrolysed by rabbit liver microsomal epoxide hydrolase to (-)-(R,R)-trans-3,U-dlhydroxy-tetra- 

The conformational analysis of certain 1,2-anhydrohexopyranose derivatives, and the synthesis of branched-chain sugars from epoxide precursors are covered in Chapters 20 and 13 respectively. 

OxlransEpoxides can be synthesized directly from certain diols by addition of an equivalent of tosyl chloride to the diol under phase-transfer conditions (e.g., BnNEt. Cl—CH2CI2 - sat.aq. NaOH). In this way high yields of 5,6-anhydro-3- -benzyl-l,2-0-lsopropyll-dene-a-D-glucofuranose and related 5,6-anhydrides were obtained. 

On exposure of methyl 4,6-0-benzylldene-2- -tosyl-a-D-gluco-pyranoside to similar phase-transfer conditions, the corresponding 

Epoxidation with MCPBA led to concomitant Baeyer-Vllliger oxidation 

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