title: Hydroxide-catalyzed isomerization of D-[1-13C]mannose: evidence for the involvement of 3,4-enediols.
abstract: The KOH-catalyzed isomerization of D-[1-13C]mannose under anaerobic conditions was studied by 13C-n.m.r. spectroscopy. D-[1-13C]Glucose and D-[1-13C]fructose are generated during the reaction, as expected. In addition, however, [6-13C]glucose, [6-13C]mannose, and [6-13C]fructose are produced in small proportions, possibly via symmetrical 3,4-enediol intermediates. The involvement of the latter structures in 13C-label shifting is inferred from the observation of [1-13C]sorbose and [6-13C]sorbose in the reaction mixture.
mesh_terms: D002247:Carbon Isotopes; D055598:Chemical Phenomena; D002621:Chemistry; D005632:Fructose; D005947:Glucose; D007536:Isomerism; D008358:Mannose
chemical_list: D002247:Carbon Isotopes; D005632:Fructose; D005947:Glucose; D008358:Mannose