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1

Trehaloza – właściwości, biosynteza, zastosowanie

Burek M., Waśkiewicz S., Wandzik I., Kamińska K.

Chemik

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2015

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Vol. 69, nr 8

469--476

PL

α,α-Trehaloza jest naturalnie występującym disacharydem, zbudowanym z dwóch cząsteczek glukozy połączonych wiązaniem α,α- 1,1’-O-glikozydowym. Znana jest głównie ze zdolności do stabilizacji białek w warunkach stresu środowiskowego oraz hamowania ich agregacji. Po opracowaniu wielkotonażowej, biotechnologicznej metody produkcji, trehaloza znalazła liczne zastosowania w różnych gałęziach przemysłu, głównie w przemyśle spożywczym, kosmetycznym, farmaceutycznym i medycynie. Dowiedziono, że właściwości bioprotekcyjne trehalozy zostają zintensyfikowane w przypadku jej glikopolimerów.

EN

α,α -Trehalose is naturally occurring disaccharide composed of two glucose molecules linked by α,α -1,1’-O-glycosydic bond. It is primarily known from its ability to protect proteins during environmental stresses and inhibition of their aggregation. The development of largescale bioprocess has allowed to use trehalose in various applications, mainly in the food, cosmetic and pharmaceutical industry as well as in medicine. It was reported that bioprotective properties are amplified when trehalose is incorporated in polymer chain as a pendant group.

2

Regio- and Stereoselectivity in Glycosylation of Partially Protected 1-Thioglycosides with Glycals

Pastuch G., Wandzik I., Szeja W.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 2

161-170

EN

We present herein studies of the influence of silyl protecting groups on regio- and stereoselectivity of glycosylation of partially protected (5-nitro-2-pyridyl) 1-thioglycosides with glycals.

3

Stereoselective Synthesis of (1--6)-alfa-Linked Di- and Trisaccharides, Derivatives of 2-Deoxysugars

Wandzik I., Pastuch-Gawołek G., Szeja W.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 10

1681-1687

EN

We present herein the totally stereoselective synthesis of (1--6)-alfa-linked di- and trisaccharides by addition of thioglucosides to D-glucals.

4

High-performance liquid chromatography separation of glycerol derivatives on a chiral stationary phase

Bugla J., Wandzik I., Szeja W.

Acta Chromatographica

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2005

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No. 15

173-182

EN

We report herein the separation of enantiomers of glycerol derivatives on a cellulose-modified chiral column (Chiracel OD) in normal-phase mode. This method is suitable for monitoring the progress of the reaction and for determination of the enantiomeric purity of products. The lipase Novozyme 435-catalysed enantioselective hydrolysis of 1-O-benzyl-2,3-di-O-octanoyl-rac-glycerol has been shown to be an efficient method for preparation of 1-O-benzyl-2-O-octanoyl-sn-glycerol with high enantiomeric excess (ee > 95%).

5

Stereoselective One-Pot Synthesis of Isomaltooligosaccharides

Pastuch G., Wandzik I., Szeja W.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 8

995-999

EN

A highly stereoselective synthesis of _-linked (1_6)-gluco- di- and trisaccharides has been described. In this procedure two thioglucosides, (5-nitro-2-pyridyl) 1-thio-_- D-glucopyranoside and 6-O-tritylated ethyl 1-thioglucoside were applied as an acceptor and a donor respectively.

6

Glikozylacja z zastosowaniem pochodnych 1-tiocukrów jako substratów

Szeja W., Bugla J., Niemiec A., Pastuch G., Kasprzycka A., Ślusarczyk A., Wandzik I., Bieg T., Przybysz B., Bogusiak J.

Wiadomości Chemiczne

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2002

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[Z] 56, 7-8

605-625

EN

It was found that carbohydrate part of complex glycosides may act as antigens or receptors for proteins, and these findings led to the discovery of the important role of carbohydrates in cell-cell recognition phenomena and cell differentiation. At the same time the methods of glycosylation underwent rapid development. The present paper gives an overview of development of 1-thiosugar derivatives in oligosaccharide synthesis. In the first part of this review, recent results of the use of thioglycosides, dithiocarbonates, dithiocarbamates and thiophosphates as glycosyl donors and acceptors are presented. A survey of important methods for the synthesis of thiosugars is presented, followed by discussion of methods converting anomeric substituent into a good leaving group (activation) in nucleophilic substitution reaction. The mechanism and procedures, which provide stereoselective formation of 1,2-cis and 1,2-trans glycoside bond, are discussed. The versatility of 1-thiosugar derivatives in synthetic carbohydrate chemistry is illustrated by selective activation strategies. The most important synthetic methodologies of the synthesis of oligosaccharides like linear glycosylation strategy in step-by-step and multistep "one-pot" sequence, "armed-disarmed" glycosyl donor, "latent-active" glycosylation, orthogonal strategy are illustrated on several examples. The last part is devoted to methods for solid support oligosaccharide synthesis.

7

Stereoselective Synthesis of 2-Deoxyglycosides by Use of 2-Deoxypyranosyl Dithiocarbamates as Donors

Wandzik I., Szeja W.

Polish Journal of Chemistry

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1999

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vol. 73 nr 7

1163-1170

EN

Glycosides, derivatives of 2-deoxysugars can be conveniently prepared by treatment of glycosyl dithiocarbamates (glycosyl donors) with hydroxy compounds (glycosyl acceptors) in the presence of thiophilic compounds as activators.

8

Synthesis of deoxyglycosyl dithiocarbonic acid derivatives

Wandzik I., Szeja W.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 4

703-709

EN

Dithiocarbonic acid esters of deoxy sugars (6-10) can be prepared by treatment of reducing deoxy monosaccharides (1-5) with diphenylphosphoryl chloride and sodium diethyldithiocarbamate or potassium O-ethyldithiocarbonate under phase-transfer conditions (procedure A) or with sodium hydride in anhydrous tetrahydrofuran (procedure B). Good yields and selectivity are reported for acetylated and benzylated derivatives of deoxy sugars, applying procedure B. The probable way of reaction is discussed.