摘要:
A process for the oxidation of 5-hydroxymethylfurfural which comprises oxidizing 5-hydroxymethylfurfural in an aqueous medium with oxygen in the presence of a catalyst which contains at least one metal of the platinum group.
摘要:
Sucrosetricarboxylic acid can be prepared by oxidizing sucrose with oxygen, if desired in a mixture with inert gases, by means of a more effective catalyst than platinum/alumina.The product can be used in washing agents or as a food additive.
摘要:
A process for the preparation of a mixture of sucrose oxidation products which contains a salt of sucrosetricarboxylic acid and which is obtained by reaction of sucrose with oxygen in an aqueous medium in the presence of a platinum metal/active carbon catalyst at elevated temperatures and neutralization of the reaction product to convert into the salt form, which comprises the reaction being carried out discontinuously, the starting materials being heated stepwise over the course of several hours from room temperature up to 60.degree. to 95.degree. C. and then the reaction product being isolated where appropriate.The oxidation products obtained in this way have, in particular, improved washing properties.
摘要:
Streptazoline is reacted with naphthoquinones in a Diels-Alder reaction, and the adduct is then oxidized. The resulting compounds have cytotoxic activity, in particular against leukemia cells, and have an antimicrobial action and act against protozoa.
摘要:
Dipeptide alkyl esters whose alkyl group contains 3 to 7 carbon atoms can be converted to the corresponding methyl ester compound by a rapid, gentle transesterification in anhydrous methanol in the presence of an alkali metal alcoholate, without racemization occuring on the two chiral carbon atoms.
摘要:
Microbial polysaccharides can be liberated from their amine adducts by treating them with ammonia or a highly volatile amine in the presence of monohydric alkanols having 1 to 3 carbon atoms. It is advantageous to use the amine adduct in the form of a moist press cake in which it is isolated from fermenter broths. The free polysaccharides are obtained in a virtually quantitative yield.
摘要:
Phospholipids which are obtained within the framework of protein synthesis from fermentatively produced constituents of micro-organisms may be used, following a conversion into a water-dilutable form, for example by emulsification or by a chemical modification, such as saponification or sulfonation, as greasing agents for the greasing of leather and fur skins. In this capacity they are superior to vegetable and animal phospholipids.
摘要:
Resolution of the racemates of phosphorus-containing functional acetic acid derivatives can be carried out in high yield and in enantiomeric purity using hydrolases such as esterases and lipases.
摘要:
.alpha.-Glucosyl fluoride can be converted in the presence of cyclodextrin .alpha.(1.fwdarw.4)glucosyltransferase into a mixture of .alpha.- and .beta.-cyclodextrins in high yield.