Biocatalytic Regioselective Oxidation of N-Hydroxyethyl Glucamine for Synthesis of Miglitol

Abstract

N-2-hydroxyethyl-glucamine (NHEG) was converted into 6-deoxy-6-hydroxylethyl-amino-L-sorbose (DHES) by the regioselective oxidation of Gluconobacter oxydans, and then the generated intermediate of this process was produced to N-hydroxyethyl-deoxynojirimycin (Miglitol) by reductive ring closure reaction. Regioselective oxidation reaction was catalyzed by the high activity sorbitol dehydrogenase of Gluconobacter oxydans biomass which was obtained in preliminary studies. Reductive ring closure reaction was carried out under the conditions of 10%Pd/C as catalyst, at 45~55°C and 0.6MPa of hydrogen. Reaction mixture by the separation and purification of strong acidic exchange resin column has been the Miglitol. In addition, the structure and properties of synthetic product was characterized by thin layer chromatography (TLC), melting point, mass spectrometry (MALDI-MS), Fourier transform infrared spectroscopy (FTIR) analysis. The results showed that the miglitol yield is 77.3%.The regional specificity of the high activity sorbitol dehydrogenase of Gluconobacter oxydans has been verified. Moreover, combinating the technology of the Pd/C- catalyzed reductive ring closure reaction, an effective synthesis process of miglitol is achieved.