A two-step strategy for the preparation of 6-deoxy-l-sorbose.

A two-step enzymatic strategy for the efficient and convenient synthesis of 6-deoxy-l-sorbose was reported herein. In the first reaction step, the isomerization of l-fucose (6-deoxy-l-galactose) to l-fuculose (6-deoxy-l-tagatose) catalyzed by l-fucose isomerase (FucI), and the epimerization of l-fuculose to 6-deoxy-l-sorbose catalyzed by d-tagatose 3-epimerase (DTE) were coupled with the targeted phosphorylation of 6-deoxy-l-sorbose by fructose kinase from human (HK) in a one-pot reaction. The resultant 6-deoxy-l-sorbose 1-phosphate was purified by silver nitrate precipitation method. In the second reaction step, the phosphate group of the 6-deoxy-l-sorbose 1-phosphate was hydrolyzed with acid phosphatase (AphA) to produce 6-deoxy-l-sorbose in 81% yield with regard to l-fucose.