Showing papers on "Aldose published in 1981"

Derivatives of chitins, chitosans and other polysaccharides

Abstract: Derivatives have been formed from chitins and chitosans in which the amine residues on the polyglucosamine have been modified to form the groups: (a) --N═CHR or --NHCH 2 R (b) --NHR' (c) --NHR" and (d) --NH--CH 2 CO 2 H or --NH--glyceryl where R is an aromatic moiety having at least one hydroxyl or carboxyl group, or a macrocyclic ligand R' is an aldose or ketose residue, and, R" is an organometallic aldehyde residue These derivatives are useful in chelating metals, in pharmaceutical formulations, in cosmetics, in chromatographic separations, in enzyme immobilization, as catalysts, etc Galactomannans having selected amine-containing side chains have also been prepared by reductive amination

Aq. dispersion of dyestuff insoluble in water - esp. vat or disperse dyestuff contains aldose or ketose to complex boric acid and inhibit gelation

Abstract: Aq. dyestuff dispersion contains a dyestuff (I), which is insoluble to hardly soluble in water, and aldose (IIA) or ketose (IIB) and opt. also an anionic dispersant (III), non-ionic dispersant (IV) and/or hydrotropic agent (V). Pref. (I) is a disperse or vat dyestuff, esp. a disperse anthraquinone dyestuff of formula (I), (in which R is H, 1-12C alkyl, lower hydroxyalkyl, cycloalkyl or aryl; W is H, halogen, CN, lower alkyl or lower alkoxy; n is 1 or 2; Z1-3 are H, NO2 or an OH or amino gp., opt. substd. by lower (hydroxy)alkyl, cycloalkyl or aryl. In partic., R is H, 1-4C alkyl, (halo)phenyl, 2-4C hydroxyalkyl, hydroxyphenyl, methylphenyl or methoxyphenyl. Ring A opt. has 1 or 2 Cl or Br substits.; Z2 and Z3 are H, OH or (methyl)amino; Z1 is OH or an amino gp., opt. substd. by R. (II) is pref. a pentahydroxy-aldehyde or -ketone, esp. fructose. Pref. the particle size of the constituents of the dispersion is under 10, esp. under 2 micron. The dye liquor or printing ink can also contain a thickener based on polysaccharides. The dispersions are specified for use in the prepn. of dye baths or printing inks, esp. transfer printing inks for (polyester) fibres. Since (II) are strong complexing agents for boric acid, they inhibit gelation and eliminate the need to remove boric acid from the crude (I).

A process for making ketose sugars

Abstract: Ketose sugars (for example, lactose, glucose or galactose) are produced in high yield from aldose sugars by reaction with boric acid in aqueous medium in the presence of a tertiary or quaternary amine.