120524-87-0Relevant articles and documents
Borate as a phosphate ester mimic in aldolase-catalyzed reactions: Practical synthesis of L-fructose and L-iminocyclitols
Sugiyama, Masakazu,Hong, Zhangyong,Whalen, Lisa J.,Greenberg, William A.,Wong, Chi-Huey
, p. 2555 - 2559 (2007/10/03)
Dihydroxyacetone phosphate (DHAP)-dependent aldolases have been widely used for the organic synthesis of unnatural sugars or derivatives. The practicality of using DHAP-dependent aldolases is limited by their strict substrate specificity and the high cost and instability of DHAP. Here we report that the DHAP-dependent aldolase L-rhamnulose 1-phosphate aldolase (RhaD) accepts dihydroxyacetone (DHA) as a donor substrate in the presence of borate buffer, presumably by reversible in situ formation of DHA borate ester. The reaction appears to be irreversible, with the products thermodynamically trapped as borate complexes. We have applied this discovery to develop a practical one-step synthesis of the non-caloric sweetener L-fructose. L-Fructose was synthesized from racemic glyceraldehyde and DHA in the presence of RhaD and borate in 92% yield on a gram scale. We also synthesized a series of L-iminocyclitols, which are potential glycosidase inhibitors, in only two steps.
Process for forming omega-deuxy-azasugars
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, (2008/06/13)
A process for the preparation of a 1,5-dideoxyazafuranose or 1,6-dideoxy-azapyranose is disclosed. In such a process, an azido-substituted α-ketose phosphate having a five- or a six-carbon chain is hydrogenated in the presence of a palladium catalyst. The carbon atom bearing the azido substituent and the carbon atom of the keto group of the α-ketose phosphate starting material are separated by two or three carbon atoms.
Use of Dihydroxyacetone Phosphate Dependent Aldolases in the Synthesis of Deoxyazasugars
Liu, Kevin K.-C.,Kajimoto, Tetsuya,Chen, Lihren,Zhong, Ziyang,Ichikawa, Yoshitaka,Wong, Chi-Huey
, p. 6280 - 6289 (2007/10/02)
The use of fructose-1,6-diphosphate (FDP), fuculose-1-phosphate (Fuc-1-P) and rhamnulose-1-phosphate (Rham-1-P) aldolases in organic synthesis is described.Fuc-1-P, Rham-1-P, and their phosphate-free species have been prepared and characterized.Both Fuc-1-P and Rham-1-P aldolases accept 3-azido-2-hydroxypropanal as a substrate to form L-ω-azidoketose phosphates, which upon dephosphorylation and hydrogenolysis on Pd/C, gave 1-deoxyazasugars structurally related to D-galactose and L-mannose.Hydrogenolysis of the enzyme products azidoketose 1-phosphates, however, gave 1,6-dideoxyazasugars structurally related to 6-deoxygalactose and L-rhamnose.Explanations for the stereoselectivity in the hydrogenolysis reactions were provided.Similarly, FDP aldolase catalyzed the aldol condensation reaction with 2-azido-3-hydroxypropanal to afford a new synthesis of 2(R),5(S)-bis(hydroxymethyl)-3(R),4(R)-dihydroxypyrrolidine, a potent inhibitor of a number of glycosidases.A new empirical formula is developed to relate the inhibition constants and inhibitor binding for α- and β-glucosidases.
