Polarography of 3-Keto-Sugars

✍ Scribed by J. van Beeumen; J. De Ley

• Publisher: Wiley (John Wiley & Sons)
• Year: 2010
• Weight: 713 KB
• Volume: 80
• Category: Article
• ISSN: 0037-9646
• DOI: 10.1002/bscb.19710800539

✦ Synopsis

The polarographic features o f several 3-keto-sugars were studied. The effects of pH, incubation time, boric acid and concentration were determined. Spectrophotometric measurements were carried out simultaneously. The structure of 3-keto-lactose in aqueous solutions, its chemical conversions at higher p H and the electroreduction mechanism were deduced. There is evidence that the carbonyl function of various 3-uloses in neutral, slightly acid and basic solutions is hydrated, the degree of hydration varying with the type of the 3-ulose. As the electroreduction occurs only at the free carbonyl function, the limiting current is determined by the dehydration rate. Their polarographic properties indicate that the ketones are readily reducible in a two-electron process, presumably to the corresponding isomeric sugars. There is strong evidence that reductones are formed in alkaline conditions.