In the phase transfer system solid calcium carbonate-acetonitrile, per acetate alpha-D-glucosaminilchloride glycosilate easily deprotoned isatine-3-oximes hydroxyl groups. It was found that the presence in the reaction mixture a catalytic amounts of 15-crown-5 accelerated the process twice. Obtained O-beta-D-glucosaminides were identified with 1H-NMR spectroscopy. Features of synthesized compound's NMR spectra are discussed in comparison with those of another N-acetylglucosamine 1-O-derivatives. The biological activity of the some oximes with different substituents in isatin residuum has been studied in a test of inhibition of bioluminescence of marine luminescent bacteria Photobacterium leiognathi Sh12. The nature of N-substituent of isatin fragment and 5-substituent of isatin main structure is compared with glycosides ability to suppress bacterial luminescence.

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The crown ether-catalyzed glycosylation of phenol, 4-methoxyphenol, and 4-nitrophenol was studied under phase transfer conditions in solid-liquid system. The asymmetric dibenzocrown esters are superior to [3.3]dibenzo-1 8-crown-6 and 15-crown-5 in the catalysis of these reactions. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 3; see also http://www.maik.ru.

From glucosaminyl chloride peracetate, in the presence of HgI 2, we have obtained fl-p-nitrobenzyl-, fl-o~-chloro-and fl-w-azido-spacered glycosides of N-acetylglucosamine (NAG) [7] protection; and also o~-azidoalkyl glycosides [8]. In recent years, great interest has been aroused by w-halogenoalkyl glycosides, which are easily modified to form oJ-carboxy and oJ-amino derivatives or glycolipids [9].As catalyst in the synthesis of glycosides of N-acetylglucosamine (NAG)glycosides, we propose HgI 2, which permits the use of a readily obtainable and stable glycosyl donor --the a-chloride (1) [10]. Our aim was to develop a convenient method of synthesizing oJ-chloro-and oJ-amino-spacered glycosides of NAG with spacers of different chemical natures, and their modification.The glycosylation of p-nitrobenzyl alcohol with the ,~-chloride (1) was carried out at room temperature in dichloroethane in the presence of mercury(II) iodide and molecular sieves 3. The ~-p-nitrobenzyl glycoside (2) was obtained by crystallization with a yield of 52 %. Its structure was confirmed by its PMR spectrum, in which we identified signals from the protons of the carbohydrate residue (see the Experimental part) and the aglyeon: two doublets of an AB-system of methylene protons with CSs of 4.70 and 5.02 ppm and twJo doublets of aromatic protons with CSs of 7.48 and 8.20 ppm. The 8-configuration of the glycosidic bond followed from the presence in the spectrum of the doublet of the anomeric proton with a CS of 4.76 ppm and the SSCC 8.5 Hz. The nitro group in compound (2) was subjected to hydrogenation over a platinum catalyst, and the amine (3) obtained was converted by the action of 2-dodeeyltetradecanoic acid into the lipophilie derivative (4). AS compared with that of compound (2), its PMR spectrum contained an additional triplet with a CS of 0.88 ppm from two terminal methyl groups and an intense multiplet of methylene protons with a CS of 1.24 ppm, which confirmed the introduction of the lipophilic component.Analogously, the interaction of 4-chlorobutyl and 6-chlorohexyl alcohols with the a-chloride (1) gave the chloroglycosides (Sa, b), which we had obtained previously by an oxazoline synthesis [8]. The treatment of chlorine derivatives (Sa, b) with sodium azide in the presence of tetraethylammonium bromide led to the oJ-azidoalkyl glycosides (6a, b). The PMR spectrum of compound (6a) included a triplet with the CS 3.23 ppm of a oJ-methylene group, two multiplets with CSs of 3.49 and 3.81 ppm of nonequivalent protons of an a-methylene group, and two multiplets with CSs of 1.18 and 1.59 ppm for the other CH 2 groups (see the Experimental part). The Zemplen deacetylation of glycoside (6a), followed by reduction of the azido function, led to the amine (8a), from which, by the method of [11], we obtained a conjugate of B-N-acetylglucosamine with polyacrylamide. Such conjugates earl be used for typing lectins or antibodies [12].