Preparation of ursodeoxycholic acid by direct electro-reduction of 7-ketolithocholic acid

A novel method of producing ursodeoxycholic acid was developed through direct electro-reduction of 7-ketolithocholic acid in a divided electrolytic cell. Titanium ruthenium mesh electrode was used as the anode, while high purity lead plate was used as the cathode. The process was optimized with regards to the electrolyte, temperature, concentration of methanol, current density and concentration of anolyte. When potassium bromide was used as the electrolyte, the saturated solution of 7-ketolithocholic acid in 85–93% (v/v) methanol, current density 9.52–28.6 A/m 2 and concentration of anolyte at 4–6% (w/w), the maximum percentage yield of ursodeoxycholic acid could be 47%. The method will provide a potential approach for large-scale production of ursodeoxycholic acid.