). Dowex 50 x 8 (200-400 mesh) cation-exchange resin in the H + form (250 mg; dried at >100 o C under high vacuum for 2 h), the C-labeled D-aldohexose (250 mg, 1.39 mmol) was added to MeOH (10 mL), and the mixture was refluxed overnight with stirring. After cooling to RT, the resin was removed by filtration and the filtrate was concentrated at 30 o in vacuo. The crude residue was dissolved in a minimal volume of distilled water, and the solution was applied to a chromatography column (2.5 cm x 100 cm) containing Dowex 1 x 8 (200-400 mesh) anion-exchange resin in the OHform. The column was eluted with decarbonated, distilled water and fractions (10 mL) were assayed by TLC analysis using a cerium molybdate stain and charring with a heat gun. For 1-4 (Glc and Gal), the a-anomer eluted first, followed by the b-anomer. For 5 (Man), the b-anomer eluted first, followed by the a-anomer. Yields: 1 1,2 , 45.6% as a white solid; 2 1,2 , 22.4% as a white