Synthesis of 1-C 14 -L-Ascorbic Acid

Abstract

The synthesis involves addition of labelled cyanide to L-xylosone to form imino-L-ascorbic acid which is hydrolyzed to L-ascorbic acid in 2.6 [image] HCl at 50cC for 22 hrs. Impurities are removed by adsorption on an Amberlite ion-exchange column, followed by selective elution. The eluate containing ascorbic acid is concentrated by evaporation under N2, taken up in alcohol, subjected to ether-alcohol fractionation, and the ascorbic acid is crystallized from a methanol-ether-ligroin solvent mixture at -15[degree]C. Final yield is approx. 25%, based on the quantity of NaC14N used in the synthesis.