摘要:
Carbohydrate-containing polymers which can have an HLB* of from about 10 to about 20 are disclosed. The compounds comprise a hydrophilic polymer portion, a carbohydrate portion comprising from 1 to about 20 naturally occurring, identical or different, monosaccharide units, at least one bifunctional spacer coupling the carbohydrate portion to the hydrophilic polymer portion, and a potentiator moiety. The potentiator moiety can be is a crosslinking moiety located within the hydrophilic polymer or a hydrophobic, hydrophilic or ionic moiety. Processes for the preparation and use of such polymers are also disclosed.
摘要:
The invention relates to elaiophylin derivatives of the formula I, II and III ##STR1## in which the substituents R(1), R(2), R(3) and R(3)' have the specified meanings. The compounds have antibacterial and antiviral activity.
摘要:
The invention relates to elaiophylin derivatives of the formula I, II and III ##STR1## in which the substituents R(1), R(2), R(3) and R(3)' have the specified meanings. The compounds have antibacterial and antiviral activity.
摘要:
A process for the production of 2-alkyl-3-aroyl-5-nitrobenzofurans by acylation of 2-(2-hydroxy-5-nitrophenyl)-1-aryl-ethanones and subsequent treatment of the esters with combinations of bases and proton acids or Lewis acids. This process can be used for the production of Dronedarone. Furthermore, novel intermediates for the manufacture of Dronedarone are provided.
摘要:
A process for the production of Dronedarone intermediates of the formula (I), by acylation of 2-(2-hydroxy-5-nitrophenyl)-1-(4-methoxyphenyl)-ethanone, subsequent treatment of the ester with bases and a zeolite (alumosilicate) catalyst and optional subsequent demethylation. This process can be used for the production of Dronedarone.
摘要:
A process for preparing polyvalent, physiologically degradable carbohydrate-containing polymers by enzymatic glycosylation reactions is described. The carbohydrate-containing polymers thus prepared may be used for preparing carbohydrate building blocks. The polyvalent carbohydrate-containing polymers of the invention cause no intolerance reactions in vivo, either in their intact form or in the form of degradation products. The carbohydrate side chain of the carbohydrate-containing polymer is assembled by enzymatic glycosylation reactions in homogeneous aqueous buffer systems directly on a biodegradable polymer. The yields of the glycosylation reaction are significantly improved over known processes, and are often quantitative. This also provides a significant increase in the loading densities. A process for preparing free oligosaccharides by means of the carbohydrate-containing polymers of the invention is also described.
摘要:
Methods for the enzyme catalyzed acylation of primary and secondary alcohols using an enol ester as the acyl donor are described. The acylation occurs in organic media, and is enantioselective for racemic or prochiral alcohols. The reaction is irreversible, and produces unreactive by-products.
摘要:
The invention relates to conjugates which consist of mono- or polycarboxylated piperidine or pyrrolidine derivatives and pyranoses, furanoses or polyalcohols linked via a chain or a cyclic system. The carboxyl groups of the piperidine derivatives can either be located directly on the ring or linked to the ring via a short chain. The invention additionally relates to the preparation of these compounds and to their use for the production of pharmaceuticals and diagnostics.
摘要:
Process for the biotechnological preparation of L-thienylalanines in enantiomerically pure form from 2-hydroxy-3-thienylacrylic acids L-Thienylalanines are prepared via the hydantoin or the azlactone route. The starting substances used for the biotransformation are 2-hydroxy-3-thienylacrylic acids. The innovative step consists in the transamination of the enol form of the 2-hydroxy-3-thienylacrylic acids to give L-thienylalanines with the aid of biotransformation. The transaminiation is carried out in the presence of L-aspartic acid or L-glutamic acid as amino donor.
摘要:
The O-acylation of alcohols is carried out by reacting a vinyl ester or a carboxylic ester with Pseudomonas lipase immobilized on a hydrophobic carrier such as a polystyrene-based carrier. The polystyrene carrier preferably has a surface area of 100-1000 m.sup.2 /g, a pore volume of 25 to 75% and a pore diameter of 25-1200 .ANG.. Crosslinking may be carried out after the lipase is immobilized on the carrier.