Isomaltol preparation

The finding that the furanone is produced from an Amadori compound was interesting in that it permitted us to test, for the first time, the effect of pH on the products of the reaction. This is not possible using a hexose- derived Amadori compound, because the end products are not stable. The product of 1,2-enolization (3-deoxyosone intermediate) is HMF, which is stable, but the product derived from 2,3 enolization (1-deoxyosone intermediate), maltol and isomaltol are not stable in aqueous solution and thus cannot be detected and measured accurately. In our experiment (Scheme 6), we prepared 1-deoxy-dibenzylamino (13), and -benzylamino (12) D-fructuronic acids, as well as... 

The first method uses 3-iodofuran as starting material, which is not readily accessible. The other uses isomaltol, which can be prepared from lactose in two steps. The longer method, on the other hand, goes via stages which are reproducible, and according to our experience the yields are satisfactory. 3,4-Dimethoxyfuran shows a very high diene activity which has been mentioned in Section IV, B. 

Hogde, J.E. Nelson, E. C. Preparation and properties of galactosylisomaltol and isomaltol. Cereal Chem. 1961, 38,2Ql-22. ... 

---