Showing papers on "Aldose published in 1980"

Human brain aldehyde reductases: relationship to succinic semialdehyde reductase and aldose reductase.

Abstract: Human brain contains multiple forms of aldehyde-reducing enzymes. One major form (AR3), as previously shown, has properties that indicate its identity with NADPH-dependent aldehyde reductase isolated from brain and other organs of various species; i.e., low molecular weight, use of NADPH as the preferred cofactor, and sensitivity to inhibition by barbiturates. A second form of aldehyde reductase ("SSA reductase") specifically reduces succinic semialdehyde (SSA) to produce gamma-hydroxybutyrate. This enzyme form has a higher molecular weight than AR3, and uses NADH as well as NADPH as cofactor. SSA reductase was not inhibited by pyrazole, oxalate, or barbiturates, and the only effective inhibitor found was the flavonoid quercetine. Although AR3 can also reduce SSA, the relative specificity of SSA reductase may enhance its in vivo role. A third form of human brain aldehyde reductase, AR2, appears to be comparable to aldose reductases characterized in several species, on the basis of its activity pattern with various sugar aldehydes and its response to characteristic inhibitors and activators, as well as kinetic parameters. This enzyme is also the most active in reducing the aldehyde derivatives of biogenic amines. These studies suggest that the various forms of human brain aldehyde reductases may have specific physiological functions.

Ketose sugars from aldose sugars

Abstract: Ketose sugars are prepared in high yield by reacting an aldose sugar and boric acid in aqueous medium in the presence of a tertiary or quaternary amine.

Inhibitor for aldose reducing enzyme

Abstract: PURPOSE: An inhibitor for aldose reducing enzyme useful for preventing and remedying diabetic cataract, neurosis, retinopathy, etc., comprising a thazolidine derivative. CONSTITUTION: An inhibitor for aldose reducing enzyme comprising a thiazolidine derivative shown by the formula (R is H, lower alkyl, OH, alkoxy, nitro, amino, lower acylamino, halogen, or CF 3 ). The compound suppresses the reduction from glucose to sorbitol, prevents or reduces the accumulation of sorbitol in the lens, peripheral nervous system, and liver of diabetic patient, and controls complicating diseases. A compound shown by the formula wherein R is H or halogen other than F is a novel compound. A dose per adult is 0.2W1,000mg per day, and the compound is used as 0.001W1wt% solution for instillation. COPYRIGHT: (C)1982,JPO&Japio

Process for the preparation of chlorodeoxysugars

Abstract: A process for the preparation of a chlorodeoxy derivative of a reducing aldose having a primary hydroxy group in an exocyclic -CH 2 OH group, in which the said primary hydroxy group is replaced by a chlorine atom to give a chlorodeoxy reducing sugar with a free anomeric center, characterized in that the free reducing sugar is reacted with a reagent comprising an N,N-dialkyl (methaniminium) chloride obtained by reacting an N,N-dialkyl formamide with a chlorinating agent.

Revision of the structures of partially acylated derivatives of aldose diethyl dithioacetals

Abstract: 1H nuclear magnetic resonance spectroscopy is used to correct the structures of most of the known partially acylated derivatives of aldose diethyl dithioacetals which contain more than one acyl group. Previous work had suggested that the hydroxyl group on carbon-2 was the least readily acylated secondary hydroxyl group; current work indicates that it is among the most readily acylated. Evidence is presented which shows that the preferential methylation of aldose diethyl dithioacetals at O-2 is caused by the presence of the sulfur atoms.