Chemical synthesis of UDP-β- -arabinofuranose and its turnover to UDP-β- -arabinopyranose by UDP-galactopyranose mutase

Uridine-5′-diphospho-β- -arabinofuranose, a possible donor of -arabinofuranose residues in plants, was synthesized. This compound, in the presence of UDP-galactopyranose mutase, underwent interconversion with UDP-β- -arabinopyranose that is a likely precursor of -arabinofuranose in vivo. This result provided a working model for the biogenesis of arabinofuranose in plants.