title: Paramolybdate anion-exchange resin, an improved catalyst for the C-1-C-2 rearrangement and 2-epimerization of aldoses.
abstract: Aqueous solutions of molybdate at 90 degrees bring about the inversion of the C-1-C-2 fragment of aldoses having four or more carbon atoms, generating thermodynamically equilibrated mixtures of the starting aldose and its 2-epimer. In some cases, notably with the aldopentoses, substantial proportions of the 3-epimers are produced, as well as 2-epimers that have not undergone inversion of the C-1-C-2 fragment. These side-reactions can be controlled by using the paramolybdate form of an anion-exchange resin (AG MP-1) together with the formate form of the same resin. The latter acts to scavenge unbound molybdate and paramolybdate anions that appear to be responsible for the side reactions.
mesh_terms: D000837:Anion Exchange Resins; D002236:Carbohydrate Conformation; D055598:Chemical Phenomena; D002621:Chemistry; D007202:Indicators and Reagents; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D008982:Molybdenum; D009005:Monosaccharides; D012117:Resins, Synthetic
chemical_list: D000837:Anion Exchange Resins; D007202:Indicators and Reagents; D009005:Monosaccharides; D012117:Resins, Synthetic; C032926:Bio-Rad AG-MP 1; D008982:Molybdenum