| 摘要 |
L-sucrose or beta -L-fructofuranosyl alpha -L-glucopyranoside-(I), the enantiomer of naturally occuring D-sucrose, which does not appear in nature has been synthesized and has been found to be sweet. It is unlikely that L-sucrose is metabolized in the manner of D-sucrose. In a preferred process for producing L-sucrose the key step is the condensation of 2,3,4,6-tetra-O-benzyl- alpha -L-glucopyranosyl chloride-(II) with 1,3,4,6-tetra-O-benzyl-L-fructofuranose-(III). Compound II is obtained from L-glucose by way of 2,3,4,6-tetra-O-benzyl- alpha -L-glucopyranose; and L-glucose is prepared from L-arabinose by nitromethane synthesis. Compound III is obtained by oxidation, with Jones reagent, of 1,3,4,6-tetra-O-benzyl-L-mannitol which, in turn, is prepared from L-mannose. The condensation product of II and III is catalytically debenzylated to produce L-sucrose. |
