title: Two-step enzymatic synthesis of 6-deoxy-L-psicose.
abstract: Rare sugars offer a plethora of applications in the pharmaceutical, medicinal, and industries, as well as in synthetic chemistry. However, studies of rare sugars have been hampered by their relative scarcity. In this work, we describe a two-step strategy to efficiently and conveniently prepare 6-deoxy-L-psicose from L-rhamnose. In the first reaction step, the isomerization of L-rhamnose (6-deoxy-L-mannose) to L-rhamnulose (6-deoxy-L-fructose) catalyzed by L-rhamnose isomerase (RhaI), and the epimerization of L-rhamnulose to 6-deoxy-L-psicose catalyzed by D-tagatose 3-epimerase (DTE) were coupled with selective phosphorylation reaction by fructose kinase from human (HK), which selectively phosphorylate 6-deoxy-L-psicose at C-1 position. 6-deoxy-L-psicose 1-phosphate was purified by a silver nitrate precipitation method. In the second step, the phosphate group of the 6-deoxy-L-sorbose 1-phosphate was hydrolyzed with acid phosphatase (AphA) to produce 6-deoxy-L-psicose in 81% yield with respect to L-rhamnose. This method allows that the 6-deoxy-L-psicose to be obtained from readily available starting materials with high purity and without having to undergo isomer separation.
authors.affiliation: Department of Chemistry, Georgia State University, Atlanta, GA 30303. USA.
authors.forename: Liuqing
authors.initials: L
authors.lastname: Wen
authors.affiliation: Department of Chemistry, Georgia State University, Atlanta, GA 30303. USA.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Huang
authors.affiliation: Department of Chemistry, Georgia State University, Atlanta, GA 30303. USA.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: National Glycoengineering Research Center, Shandong University, Jinan, Shandong 250100. People's Republic of China.
authors.forename: Junqiang
authors.initials: J
authors.lastname: Fang
authors.affiliation: Department of Chemistry, Georgia State University, Atlanta, GA 30303. USA.
authors.forename: Shukkoor Muhammed
authors.initials: SM
authors.lastname: Kondengaden
authors.affiliation: Department of Chemistry, Georgia State University, Atlanta, GA 30303. USA.
authors.forename: Peng George
authors.initials: PG
authors.lastname: Wang
keywords: 6-deoxy-L-psicose; Dephosphorylation; Enzymatic synthesis; One-pot multienzyme; Phosphorylation