Aldose

About: Aldose is a research topic. Over the lifetime, 1270 publications have been published within this topic receiving 27197 citations. The topic is also known as: aldoses.

Synthesis of a Ketose from a Partially Benzylated Aldose: d-threo-Pentulose from 2,3,5-Tri-O-benzyl-d-arabinofuranose

Abstract: Publisher Summary This chapter discusses the synthesis of a ketose from a partially benzylated aldose. Aldopyranoses and aldofuranoses that are fully benzylated except at C-1 and at the other carbon atom involved in the hemiacetal ring (C-4 or C-5) are readily accessible through the benzylation and subsequent hydrolysis of aldosides; the preparation of 2,3,4,6-tetra-O-benzyl-α- d -glucopyranose. Such benzylated aldoses are readily reduced to the corresponding partially benzylated alditols through the action of sodium borohydride or lithium aluminum hydride. Selective blocking of the primary hydroxyl group in such substituted alditols leaves only the secondary hydroxyl group available for oxidative attack; removal of the masking groups subsequent to oxidation gives a ketose in which the reducing carbon atom represents C-4 or C-5 in the original aldose.

Human Kidney Aldose and Aldehyde Reductases Sat0

Abstract: Mounting experimental evidence links increased aldose reductase activity with diabetes-related kidney functional changes. To investigate the interrelationship of NADPH-dependent reductases in the human kidney, both aldose reductase and aldehyde reductase were purified from human kidney by a series of chromatographic procedures, including gel filtration on Sephadex G-100, affinity chromatography on Matrex Gel Orange A, and chromatofocusing on Mono P. Each purified enzyme appeared as a single band on polyacrylamide gel after electrophoresis or isoelectric focusing. Aldose reductase has a p1 of 5.7 and apparent molecular weight of 37 kDa, calculated from SDS-polyacrylamide gel electrophoresis, while aldehyde reductase has a p1 of 5.2 and molecular weight of 39 kDa. Similar molecular weights were also obtained by gel filtration, indicating that both aldose and aldehyde reductases are present as monomers in the human kidney. Aldehyde reductase is primarily localized in the cortex, while the medulla contains aldose

Method for producing aldose

Abstract: PROBLEM TO BE SOLVED: To provide an industrial method for inexpensively and safely producing aldose in high yield by subjecting aldonic acid to decarboxylation reaction to produce a corresponding aldose as being accompanied by decrease of one carbon atom. SOLUTION: In the process for producing aldose from aldonic acid by using hypochlorous acid or a hypochlorite salt as one of carbon atoms is decreased, a compound having higher reactivity to the hypochlorous acid or its salt than that of the reaction product (namely aldose of which one carbon number is decreased) is added to the reaction mixture. COPYRIGHT: (C)2005,JPO&NCIPI

Differentiation of the Coordination Chemistry of Metal Chlorides in Catalytic Conversion of Glucose in Ionic Liquids

Abstract: Catalytic aldose isomerization to ketose is an important reaction for the utilization of cellulosic biomass. However, a fundamental understanding and knowledge base involved in this reaction remains lacking in the literature. In this chapter, we provide a focused review of the most studied solvent-based catalytic system involving metal halides for glucose isomerization to fructose and further to 5-hydroxymethhylfurfral (5-HMF). Results from studies by different physical techniques are critically reviewed. A differentiation of the coordination chemistry of different metal chlorides obtained by various physical techniques is established to rationalize the drastically different catalytic pathways by the metal chloride catalysts. The performance of metal chloride catalysts for the isomerization of aldose to ketose is found to correlate with their coordination chemistry. Solvents play an important role in determining the coordination structures for the metal ions, which critically affect the catalysis of the metal chloride precursors. Undesired side products are related to the reaction pathways corresponding to the nature of the coordination of metal ions with different oxygen sources in the substrates and the products.