Synthesis of galactothiophosphoesters of uridine and preliminary tests to evaluate their activity against selected glycosyltransferases.

Glycoconjugates (8-13) were obtained in condensation reaction of selectively protected thiophosphoesters of uridine with 2,3,4.6-tetra-O-acetyl-1-thio-beta-D-galactose. In sequence of reactions: selective protection of esculine, glycosylation reaction and deprotecion beta-D-galactopiranoside-(1-4)-esculine (20) was obtained as a model of the product reaction catalyzed by GTs.

Synthesis of glycinated glycoconjugates based on 1-thioglycosides and their preliminary studies as potential immunomodulatory factor.

The biological importance of lipopolysaccharides (LPS), components of bacterial cell wall has not been explained sufficiently. The glycine present in these structures could play an important role in the immunological response after bacterial infections and during sepsis. In our studies we obtained synthetic and stable substituted glycinated 1-thioglycosides derivatives of monosaccharides, e.

Glycoconjugates, products of uridine derivatives phosphitylation and oxidation as glycosyltransferases potential inhibitors.

The title compounds, variously protected 5'-uridine derivatives connected with 1-thiosugar with thio-phosphoesters fragment (17-22) were synthesized in sequence of reactions: phosphitylation--reaction of 5'-hydroxyl group of selectively protected nucleoside with a phosphitylating agent (N,N-diisopropyl chlorophosphoamidite), connection an phosphoroamidites with 2-bromoethanol or 3-bromopropanol and secondary oxidation with sulfur presence and finally condensation reaction of obtained products with 1-thiosugar. Received glycoconjugates (17-22) had a structure which mimic to structure of natural glycosyltransferases substrates.

5-Nitro-2-pyridyl-1-thioglucosides: application in synthesis of analogues of glycosyltransferases natural substrates.

5-Nitro-2-pyridyl-1-thioglucosides were used in synthesis of complex uridine derivatives (13-16) in two different sequences of reactions. In one route, the first step was glycosylation of selectively protected 5-nitro-2-pyridyl-1-thioglucoside 1 with two different glycosyl donors (5 or 6), next, the nitro group in aglycone of obtained disaccharides 7 or 8 was reduced and then obtained products 9 or 10 were condensed with uridine derivatives 3 or 4 using DMT-MM as condensing agent under microwave irradiation. In the second route, condensation and glycosylation reactions were applied in reverse order.