Wiadomości Chemiczne

Wiadomości Chemiczne, 2014, Vol.68

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  1. Legendary Beasts - Literature Versus Science
    Anna N. Wilk, Paweł Kafarski

  2. Proline as a Common Amino Acid and an Exceptional Catalyst. Part III. Mannich Reaction
    Renata Studzińska, Aleksandra Karczmarska-Wódzka, Marcin Wróblewski, Renata Kołodziejska, Marcin Dramiński

  3. Proline as a Common Amino Acid and an Exceptional Catalyst. Part IV. Michael Reaction
    Aleksandra Karczmarska-Wódzka, Renata Studzińska, Renata Kołodziejska, Marcin Wróblewski, Marcin Dramiński

  4. Synthesis and Biological Activity of Pyridopyridazine Derivatives
    Wanda Paulina Nawrocka, Anna Nowicka

  5. Syntheses of the Thiazolo[4,5-d]Pyrimidine System
    Lilianna Becan

  6. Natural Terpenoid Hydroxy- and Chlorolactones - their Occurrence and Properties
    Małgorzata Grabarczyk, Katarzyna Wińska, Wanda Mączka

  7. Synthesis and Antibacterial and Antifungal Activity in Vitro of Selected Mannich Bases
    Anna Nowicka, Hanna Liszkiewicz, Wanda Paulina Nawrocka

  8. Schiff Bases - Selected Syntheses, Reactions and Biological Activity
    Anna Nowicka, Hanna Liszkiewicz, Wanda Paulina Nawrocka

  9. Application of Quinolinium and Pyridinium Salts for Determination of Selected Sulfur Compounds in Biological Samples
    Paulina Furmaniak, Monika Wyszczelska-Rokiel, Paweł Kubalczyk, Rafał Głowacki

  10. Bivalent Ligands of Opioid Receptors
    Oliwia Frączak, Aleksandra Olma

  11. Methods for Calculation Interfacial Tension from Computer Simulations
    Jakub Chrzanowski, Stanisław Lamperski

  12. Methods Used to Vizualize Latent Fingerprints
    Emilia Karolina Kołek-Kaczanowska, Joanna Kreczko, Zbigniew Maćkiewicz

  13. Characteristic of the Endogenous Enkephalin Degrading Enzymes Inhibitors
    Małgorzata Sobocińska, Zbigniew Maćkiewicz

  14. Okruchy XXXI. Antoni Grabowski - chemik-esperantysta
    Ignacy Z. Siemion, Kazimiera Lukjan

  15. Crystallography in Poland
    Zofia Kosturkiewicz

  16. Structural Transformations in Crystals Induced by Photochemical Reactions
    Ilona Turowska-Tyrk, Julia Bąkowicz

  17. Electron Density Distribution in Crystals or How to See the Details of the Electronic Structure of Molecules
    Maciej Kubicki

  18. The Importance and Examples of Application of Aspherical Pseudoatom Databanks in Small-Molecule Crystallography and their Potential Use in Makromolecular Crystallography
    Paulina Maria Dominiak

  19. The Use of Topological Analysis of Electron Density in Characterization of Noncovalent Interactions
    Barbara Bankiewicz, Agnieszka Rybarczyk-Pirek, Magdalena Małecka, Małgorzata Domagała, Marcin Palusiak

  20. High-Pressure Crystallography: How to See the Structure of Materials...Deeper
    Anna Olejniczak, Kamil Dziubek, Damian Paliwoda, Witold Zieliński, Marcin Podsiadło, Andrzej Katrusiak

  21. New Methods in Investigations of Polycrystalline Materials
    Wiesław Łasocha , Katarzyna Luberda-Durnaś

  22. From Molecular Recognition to Racemic Resolution by Fractional Crystallization of Diastereomeric Salts
    Agata Białońska

  23. Structure and Pathogenesis of Disorders Releated to CNG Repeats
    Agnieszka Kiliszek, Wojciech Rypniewski

  24. High Resolution Crystallography of Macromolecules
    Mirosław Gilski

  25. Applications of Click Chemistry in Modification of Nucleosides and Oligonucleotides
    Michał Gładysz, Jan Milecki

  26. Maldi - Method for Use in Structural Analysis of Polymers
    Beata Swinarew, Andrzej Szymon Swinarew

  27. Isofalvones - Structure, Biological Activity and Determination by High Performance Liquid Chromatography
    Ilona Bachanek, Marian Czauderna

  28. Pectins - Occurrence, Chemical Constitution and Physicochemical Properties
    Hanna Pińkowska, Adrianna Złocińska

  29. Glycidyl Fatty Acid Esters and Mono-3-Chloropropane-1,2-Diol Fatty Acid Esters - New Contamination in Edible Oils
    Magda Aniołowska, Agnieszka Kita

  30. Jerusalem Artichoke as a Source of Valuable Raw Material, Especially for Food, Pharmaceutical and Cosmetic Industries
    Marek Chyc, Jan Ogonowski

  31. O-Acyl Isopeptide Method in Peptide Synthesis
    Oliwia Frączak, Aleksandra Olma

  32. Enantioselective Enzymatic Desymmetrization Catalyzed by Oxidoreductases. Dehydrogenases in Reduction Reactions - Part I
    Renata Kołodziejska, Aleksandra Karczmarska-Wódzka, Agnieszka Tafelska-Kaczmarek, Renata Studzińska, Marcin Wróblewski, Beata Augustyńska

  33. Molecularly Imprinted Polymers as Biomimetics of Metalloenzymes
    Joanna Czulak, Andrzej Trochimczuk, Anna Jakubiak-Marcinkowska

  34. Phosphoramidate Pronucleotides and their Intracellular Activation Mechanism
    Katarzyna Kulik, Janina Baraniak

  35. Algae and Human Health
    Katarzyna Godlewska, Izabela Michalak, Katarzyna Chojnacka

  36. Lithium Batteries As Modern Energy Storage Systems
    Monika Bakierska, Agnieszka Chojnacka

  37. Synthetic Equivalents of Phosphoenolpyruvate - How to Imitate the Biosynthesis of Ulosonic Acids
    Marta Agnieszka Molenda

  38. Multilayered Polymer Films Obtained by Means of Layer-By-Layer (Lbl) Method: Evolution and Applications
    Artur Jarema Wójcik

  39. The Pursuit of Soot
    Anna Kopacz

  40. Synthesis and Application of New Olefin Metathesis Catalysts
    Agnieszka Hryniewicka

  41. Synthesis and Biological Activity of Selected Mannich Bases
    Wanda Paulina Nawrocka, Anna Nowicka

  42. Enantioselective Enzymatic Desymmetrization Catalyzed by Oxidoreductases. Reduction Reactions. Part II
    Renata Kołodziejska, Aleksandra Karczmarska-Wódzka, Agnieszka Tafelska-Kaczmarek, Renata Studzińska, Marcin Wróblewski, Beata Augustyńska

  43. Two Decades of Chemo-Enzymatic Baeyer-Villiger Reaction
    Agnieszka Drożdż, Rafał Bielas, Anna Chrobok

  44. Microbial Alcohol Dehydrogenases - Properties and their Application
    Ewa Szczepańska, Filip Boratyński

  45. Chemical Composition and Biological Activity of Medical Lavender
    Michalina Adaszyńska-Skwirzyńska, Maria Swarcewicz

  46. 60 Lat Chemii na Uniwersytecie Wrocławskim
    Kazimiera Lukjan

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LEGENDARY BEASTS - LITERATURE VERSUS SCIENCE

Anna N. Wilka, Paweł Kafarskib*

aInstytut Filologii Słowiańskiej, Uniwersytet Wrocławski, ul. Pocztowa 9, 53-313 Wrocław
bWydział Chemiczny, Politechnika Wrocławska, Wybrzeże Wyspiańskiego 27, 59-370 Wrocław
*e-mail: pawel.kafarski@pwr.wroc.pl


Vampire, werewolf or zombie are individuals more and more often met in horrors. Since their existence seems to break down all rules of science literature experts consider them exclusively as metaphor of human anxiety towards unknown and incomprehensible and unexplored issues. Such a definition of these monsters is well acknowledged in literature and cinematography. However, this seems not to be fully true because there exist some rationales and some proofs that these mystic characters might be seen in reality.

Keywords: monsters, literature, film, toxins, metabolic diseases, natural products


Wiadomości Chemiczne, 2014, 68, 1.
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PROLINE AS A COMMON AMINO ACID AND AN EXCEPTIONAL CATALYST. PART III. MANNICH REACTION

Renata Studzińska*, Aleksandra Karczmarska-Wódzka, Marcin Wróblewski, Renata Kołodziejska, Marcin Dramiński

Katedra i Zakład Chemii Ogólnej Uniwersytetu Mikołaja Kopernika, Collegium Medicum w Bydgoszczy, ul. Dębowa 3, 85-626 Bydgoszcz
*e-mail: rstud@cm.umk.pl


Mannich reaction occuring among ketone, aldehyde, and amine is one of the ways of a synthesis of biologically active compounds. Reactions of this type were carried out in the presence of different catalysts [3-10], however in recent years a lot of attention has been paid to enantioselective Mannich reaction catalyzed with proline. Such reactions were carried out with the use of different compounds containing carbonyl group and the most frequently used amine was p-anisidine. The advantage of the use of p-anisidine is a possibility of conducting the direct Mannich reaction (Scheme 3). In this way β-amino ketones (Tab. 1, 2, 4) [15, 18-20, 23, 24], α-hydroxy-β-amino ketones (Tab. 3) [15, 22], and β-amino alcohols (Tab. 5, 6) [25, 26] were obtained.

A possibility of syntheses of β-amino sugars and α-amino acids with their derivatives (Tab. 7) [28, 29] is worth noticing. In a great number of described reactions, the products were obtained with satisfactory yield and enantiomeric excess. Taking into consideration the difficulty of a removal of p-hydroxyphenyl group which protects amine group in the resulting products, the attempts of using different amine compounds in Mannich reactions catalyzed with proline were undertaken. The use of amines blocked by tert-butoxycarbonyl group (Boc) enabled to obtain the products with high yield and ee values (Tab. 12-15) [35-38]. However in the case of the use of Boc the reaction must be carried out in an indirect way (it is necessary to prepare imine blocked by Boc earlier).

Keywords: proline, Mannich reaction, asymmetric synthesis


Wiadomości Chemiczne, 2014, 68, 21.
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PROLINE AS A COMMON AMINO ACID AND AN EXCEPTIONAL CATALYST. PART IV. MICHAEL REACTION

Aleksandra Karczmarska-Wódzka*, Renata Studzińska, Renata Kołodziejska, Marcin Wróblewski, Marcin Dramiński

Katedra i Zakład Chemii Ogólnej Uniwersytetu Mikołaja Kopernika, Collegium Medicum w Bydgoszczy ul. Dębowa 3, 85-626 Bydgoszcze
*mail: akar@cm.umk.pl


In recent years there has been a dynamic development of asymmetric synthesis. Groups of researchers, particularly the one led by Benjamin List and Carlos Barbas, carried out a number of reactions and showed the effectiveness of the use of small organic molecules such as proline as catalysts. Michael addition catalyzed with proline is a particularly interesting reaction because it can be carried out in two aminocatalytic pathways. The analysis of Michael reaction reveals potential for both forms of aminocatalysis: enamine and iminium catalysis (Scheme 1) [1-14]. Presumably Michael reaction proceeds mainly according to enamine mechanism. The use of proline in Michael reaction with imine activated acceptor is slightly effective. So far the researches have shown that the modification of proline molecule or addition of other catalyst is necessary for condensation to appear. Enamine catalysis concerns the activation of carbonyl compound in situ being a donor. There is no need for enolase anion to be created earlier [2, 15-17]. When, as a result of the reaction of α,β-unsaturated carbonyl compound with proline, Michael acceptor activation appears it means that it is enamine mechanism reaction (Scheme 1) [2, 24]. One of the first examples of direct Michael reaction proceeding through enamine transition state is the reaction of cyclopentanone with nitrostyrene (Scheme 6) [20-23]. Other examples of Michael addition of ketone with nitro olefin catalysed by proline are shown in table 2 and 3 [10, 23, 30]. Nitroketones obtained in that way are useful as precursors for different organic compounds [33], also pyrrolidines [34]. Pyrrolidines are pharmacologically active and they selectively block presynaptic dopamine receptors [34] (Scheme 7).

Except for Michael intermolecular reaction, intramolecular condensation adducts were also obtained. Michael intramolecular proline-catalyzed condensation in which inactive ketones transform into α,β-unsaturated carbonyl compounds was described (Scheme 9) [35, 36]. These reactions require a stoichiometric amount of a catalyst and a long time of reaction and they give as a result a little enantiomeric excess [11, 24, 35].

In 1991, Yamaguchi and co-workers carried out malonates Michael addition to α,β-unsaturated aldehydes catalyzed by L-proline [24, 39]. The reaction proceeded according to enamine mechanism, for example dimethyl malonate was reacted with hex-2-enal in the presence of proline to give Michael adduct in 44% yield. To improve the yield an attempt of a slight modification of a proline molecule was made transforming it into proper salt. Proline lithium salt enabled to obtain the condensation product in 93% yield (Tab. 4). Regardless of a used catalyst the products in the form of racemates were obtained.

In order to improve enantioselective properties of a catalyst, Michael addition of diisopropyl malonate to cycloheptenone was carried out in chloroform in the presence of different proline salts. Optimal enantioselectivity and yield was obtained by using rubidium salt (Tab. 5-7) [40, 41].

Rubidium prolinate-catalyzed Michael additions are used in industry e.g. for enantioselective synthesis of the selective serotonine reuptake inhibitior (SSRI) (-)-paroxetine (antidepressant) (Scheme 12) [24].

Keywords: proline, Michael reaction, asymmetric synthesis


SYNTHESIS AND BIOLOGICAL ACTIVITY OF PYRIDOPYRIDAZINE DERIVATIVES

Wanda Paulina Nawrocka, Anna Nowicka

Katedra i Zakład Technologii Leków, Uniwersytet Medyczny im Piastów Śląskich we Wrocławiu, ul. Borowska 211a, 50-556 Wrocław
e-mail: anna.nowicka@umed.wroc.pl


For many years all six isomers of pyridopyridazines have been an interesting class of heterocyclic compounds because of their biological and chemical properties. Endralazine is a hypotensive drug, which contain pyrido[4,3-c]pyridazine structure.

Presented in this paper selected compounds exhibit antiviral [20] and antibacterial [21, 22] activity. Based on review of the chemical literature, derivatives of pyridopyridazine showed a multipharmacological effects such as analgesic [23-29] and diuretic [33-38] activity.

Some chemical compounds, containing pyridopyridazine moiety showed anticancer activity in vitro with different mechanism of action [12, 15, 18, 19]. Novel pyrazolopyridopyridazine derivatives have been identified as more potent and selective phosphodiesterase 5 (PDE5) inhibitors than sildenafil [41]. Pyrido[2,3-d]pyridazine derivatives were synthesized as selective PDE4 inhibitors [44-46], with good selectivity profile and less undesiderable side effects. 2,3,8-Trisubstituted pyrido[2,3-d]pyridazines were novel classes of GABA-A receptor benzodiazepine binding site ligands [30, 31]. While pyrido[2,3-c]pyridazine derivatives were selective agonists for the benzodiazepine site of GABA-A receptor [32].

Some of new substituted pyrido[3,2-c]pyridazine derivatives possess molluscicidal activity [54] and can be used as biodegradable agrochemicals.

Keywords: pyridopyridazine derivatives, structures, syntheses, biological activity


Wiadomości Chemiczne, 2014, 68, 67.
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SYNTHESES OF THE THIAZOLO[4,5-d]PYRIMIDINE SYSTEM

Lilianna Becan

Katedra i Zakład Technologii Leków, Uniwersytet Medyczny im. Piastów Śląskich we Wrocławiu, ul. Borowska 211a, 50-556 Wrocław
e-mai: lilianna.becan@umed.wroc.pl


This review is focused on the literature data about the preparation of the thiazolo[4,5-d]pyrimidine scaffold. The synthesis of this ring system has been accomplished by various methods. The synthesis can proceed via a pyrimidine onto which a thiazole ring can be annulated. The second approach involve annulation of a pyrimidine ring onto the preformed thiazole ring. Thiazolo[4,5-d]pyrimidines have been obtained by condensation of pyrimidine derivatives with thioamides [2], thionyl chloride [3], thiourea [4], bromomalononitrile [5], isothiocyanates [6] or under the influence of temperature [7]. However, most of the literature refers the methods of synthesis which begin with formation of the appropriately substituted thiazole ring. This synthetic route for preparation of fused derivatives utilizes orhtoesters [8, 9], acetic anhydride [9,10], formic acid derivatives [11, 12], carbon disulfide [13,14], appropriate isothiocyanates [15-18], urea and hydrazine derivatives [19-23], aromatic aldehydes and acid chlorides [24, 25] as key building blocks. Cyclization also occurs in high temperature or acidic reaction medium [26, 27]. The solid-phase synthesis was also described [28].

Keywords: thiazolo[4,5-d]pyrimidine derivatives, synthesis


Wiadomości Chemiczne, 2014, 68, 95.
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NATURAL TERPENOID HYDROXY- AND CHLOROLACTONES - THEIR OCCURRENCE AND PROPERTIES

Małgorzata Grabarczyk*, Katarzyna Wińska, Wanda Mączka

Katedra Chemii, Uniwersytet Przyrodniczy we Wrocławiu, ul. Norwida 25, 50-375 Wrocław
*e-mail: magrab@onet.pl


The world around us is composed of a variety of organic compounds that form the animal and plant species. One of the larger groups amongst them are terpenoid compounds, either the structurally simplest monoterpenoids, or sesquiterpenoids containing several atoms or even di- and triterpenoids composed of several carbon atoms. Many of these compounds contain lactone moiety in their structure [1-27]. Equally often, a component of their structure is a hydroxyl group [1-23]. Sometimes, the structural element can also be a halogen atom [24-27]. Many of the hydroxylactones exhibit interesting biological properties, such as antimicrobial (Fig. 1, 2, 12, 13), [2, 3, 19, 21], cytotoxic (Fig. 4, 6, 8), [8, 12, 14], anti-inflammatory (Fig. 1, 4, 11, 14), [3, 9, 18, 22], anti-fungal (112 Fig. 13), [19, 21] or liver protection (Fig. 4, 9) [8, 15]. Some of these compounds also exist as flavoring or taste agents in food (Fig. 3, 10), [7, 16], inhibitors of overproduction nitrogen sulfide (5, 6, 11), [10, 12, 18] or pesticides (Fig. 2, 13), [6, 20]. Hydroxylactones are usually isolated from plants, in many cases, those that are used in traditional folk medicine (Fig. 1, 4, 6, 7, 9, 11, 14, 15, 17), [1, 3, 8, 9, 12, 13, 15, 18, 22, 23, 25, 26], and sometimes from the other organisms, such as microorganisms or fungi (Fig. 2, 5), [6, 10]. Lactones that contain a chlorine atom in their structure, in addition to or instead of the hydroxy group usually have cytotoxic properties (16, 17), [15, 25, 27]. They are found in both land-based plants, mainly belonging to the family Asteraceae (Fig. 17) [25-27] as well as in marine organisms (Fig. 16), [24], in which the presence of chlorine atoms can be a result of the presence of salt (chloride) in seawater. The following article presents an overview of the various sources from which hydroxylactones and chlorolactones were isolated and also biological properties of these compounds.

Keywords: hydroxylactones, chlorolactones, biological activity


Wiadomości Chemiczne, 2014, 68, 117.
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SYNTHESIS AND ANTIBACTERIAL AND ANTIFUNGAL ACTIVITY IN VITRO OF SELECTED MANNICH BASES

Anna Nowicka*, Hanna Liszkiewicz, Wanda Paulina Nawrocka

Katedra i Zakład Technologii Leków Uniwersytet Medyczny im Piastów Śląskich we Wrocławiu, ul. Borowska 211a, 50-556 Wrocław
*e-mail: anna.nowicka@umed.wroc.pl


The Mannich reaction is a three-component condensation reaction involving an active hydrogen containing compound, formaldehyde and a primary or a secondary amine. The Mannich reaction is one of the most important basic reaction types in organic chemistry. This kind of aminoalkylation is important for the synthesis and modification of biologically active compounds.

Many studies have shown that Mannich bases possesses potent biological activities: antibacterial, antifungal, anti-inflammatory and antimalarial properties. Mannich bases - substituted products containing different heterocyclic moiety in their structures seem to be suitable candidates for further chemical modifications and might be of interest as pharmacologically active compounds.

The main goal of this article is to present synthesis and antimicrobial activity of selected Mannich bases. The Mannich reaction is known to be very useful for the synthesis of antibacterial compounds. The Mannich bases, containing various heterocyclic systems were identified as potent antimicrobial agents. Obtained in Mannich reaction derivatives of antibacterial drugs: ciprofloxacine, norfloxacine demonstrate higher antibacterial activity than used drugs, while derivatives of drugs: ibuporofen or phenytoine changed the profile of action of new synthesized compounds.

Keywords: Mannich bases, antibacterial activity, antifungal acivity


Wiadomości Chemiczne, 2014, 68, 161.
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SCHIFF BASES - SELECTED SYNTHESES, REACTIONS AND BIOLOGICAL ACTIVITY

Anna Nowicka*, Hanna Liszkiewicz, Wanda Paulina Nawrocka

Katedra i Zakład Technologii Leków, Uniwersytet Medyczny im Piastów Śląskich we Wrocławiu, ul. Borowska 211a, 50-556 Wrocław
*e-mail: anna.nowicka@umed.wroc.pl


Schiff bases are compounds with a functional group that contains a carbon-nitrogen double bond with the nitrogen atom connected to an aryl or alkyl group.

Schiff bases are condensation products of primary amines with carbonyl compound. Several studies showed that the presence of a lone pair of electrons on the nitrogen atom of the azomethine determine biological and chemical properties of imines. Schiff bases are generally excellent chelating agents, because of the special properties of C=N bond. Their metal complexes have been widely studied because they possess anticancer in vitro and herbicidal applications.

Imines also have biological importance. Schiff bases are common enzymatic intermediates where an amine reacts with an aldehyde or ketone of a cofactor or a substrate.

Imines have been reported for their biological properties such as antibacterial (E. coli, S. aureus), antifungal (C. albicans) activities. A large number of different Schiff bases are active against a wide range of protozoan (T. gypseum, P. viticola).

Keywords: Schiff bases, imines, biological activity, synthesis, structures


Wiadomości Chemiczne, 2014, 68, 187.
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APPLICATION OF QUINOLINIUM AND PYRIDINIUM SALTS FOR DETERMINATION OF SELECTED SULFUR COMPOUNDS IN BIOLOGICAL SAMPLES

Paulina Furmaniak, Monika Wyszczelska-Rokiel, Paweł Kubalczyk, Rafał Głowacki*

Katedra Chemii Środowiska, Wydział Chemii, Uniwersytet Łódzki
*e-mail: glowar@uni.lodz.pl


Quinolinium and pyridinium salts belong to the group of onium compounds and are widely used in organic, structural and analytical chemistry. Their synthesis is mainly based on quaternization of the nitrogen atom in a heterocyclic ring [4, 13, 23]. In analytical chemistry quinolinium and pyridinium salts such as 2-chloro-1-methylquinolinium tetrafluoroborate (CMQT) or 1-benzyl-2-chloropyridinium bromide (BCPB) perform very well as thiol specific derivatization reagents in terms of derivatization reaction velocity, stability, chromatographic properties of the derivatives, and thus, amenability to automatization [18-22, 32-42]. Analytical procedures for thiol determination usually involve reduction of disulfide bonds with tris(2-carboxyethyl)phosphine, tri-n-butylphosphine or mercaptoethanol, chemical derivatization of the sulfur compound with the use of 2-halopyridinium or 2-haloquinolinium salts and then deproteinization, followed by ion-pair reversed-phase HPLC or CE separation and spectrophotometric detection. Derivatization reaction takes advantage of great susceptibility of quinolinium or pyridinium molecules at 2-position to nucleophilic displacement, and a high nucleophilicity of the thiol group. Derivatization reaction mixture is usually ready to be analyzed just after mixing of the substrates. CMQT and BCPB exhibit very high reactivity toward thiols [44, 45], sulfides [63] as well as thiosulfates [40, 54]. 2-S-quinolinium and 2-S-pyridinium derivatives possess advantageous spectrophotometric and chromatographic properties. They are stable and more hydrophobic than thiols themselves, possessing a well-defined absorption maximum in the UV region. The reaction is accompanied by an analytically advantageous bathochromic shift from reagent maximum to the maximum of the derivative. Thanks to this phenomenon it is possible to use a large excess of derivatization reagent in order to drive the reaction to completion and avoid a huge signal of unreacted compound on the chromatogram [26]. Elaborated with the use of onium salts methods have proven to be useful in quantitative HPLC and CE analysis of endogenous and exogenous low-molecular-weight biological thiols in human body fluids, plant extracts and some groceries [44, 45].

Keywords: pyridinium salts, quinolinium salts, thiol aminoacids, chemical derivatization, high performance liquid chromatography, capillary electrophoresis


Wiadomości Chemiczne, 2014, 68, 211.
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BIVALENT LIGANDS OF OPIOID RECEPTORS

Oliwia Frączak, Aleksandra Olma*

Instytut Chemii Organicznej, Wydział Chemiczny, Politechnika Łódzka, ul. Żeromskiego 116, 90-924 Łódź
*e-mail: aleksandra.olma@p.lodz.pl


Opioids are the oldest drugs know to humanity, which have been and continue to be used for the treatment of chronic pain. Unfortunately they have a large numbers of side effects [1-6]. Three main types of opioid receptors μ (MOR), δ (DOR) and κ (KOR) are known [8]. The ORL1 receptor was classified as the fourth member of opioid receptor family [9]. Opioid receptors can form homodimers and the following heterodimers: DOR-KOR, DOR-MOR and KOR-MOR [13c,d,f, 14].

Specially designed ligands which are able to penetrate the BBB are used to study physiological consequences of opioid receptor homo- and heterodimerization, and as new analgesics.

Bivalent ligands are defined as compounds that contain two pharmacophoric units, an appropriately designed spacer to separate and define the two pharmacophores, and a linker unit to connect the pharmacophores, to the spacer (Fig. 1) [16].

The affinity of a ligand to its target depends on its fundamental kinetic association and dissociation rate constants (Scheme 1) [24]. Bivalent ligands interacting with the opioid receptors have been divided into three groups: nonpeptide, peptide-nonpeptide and peptide homo- or heterodimers. Nonpeptide bivalent ligands (4-21, 27-41 and 44-45) containing different pharmacophores (selective opioid agonists or/and antagonists) connected with designed linkers have potent analgesic properties [25-34]. Compound 35 may be useful in the treatment of opioid dependence.

Studies of peptide-nonpeptide ligands, which are a combination of "address" segments of endogenous opioid peptides and selective alkaloid ligand (47-50) indicate that peptide part of the analogues can modulate the receptor selectivity of the attached alkaloid pharmacophores [35]. Series of peptide-nonpeptide ligands containing different classes of opioid peptides and fentanyl (52-86) were synthesized and tested for binding affinity to μ and δ opioid receptors [38-40]. Good opioid affinity and antinociceptive activity of some of the obtained bivalent ligands (57, 61, 63) suggesting that a novel class of analgesics can be further developed utilizing this approach. Among homobivalent ligands the most important is biphalin 87 and its analogues (88-124) [41-53]. Analgesic potency of the most active ligand 112 is greater than parent peptide (biphalin) and morphine.

Keywords: opioid peptides, nonpeptide bivalent ligands, peptide bivalent ligands, opioid activity, homo- and heterobivalent ligands


Wiadomości Chemiczne, 2014, 68, 233.
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METHODS FOR CALCULATION INTERFACIAL TENSION FROM COMPUTER SIMULATIONS

Jakub Chrzanowski, Stanisław Lamperski

Uniwersytet im. Adama Mickiewicza w Poznaniu, Wydział Chemii, ul. Umultowska 89b, 61-614 Poznań
e-mail: qbachrzan@op.pl, slamper@amu.edu.pl


Interfaces have been recently a subject of profound interest for physicists, chemists and biologists because of the processes taking place in the interfacial region like adsorption, catalysis of chemical reactions etc. Computer simulations treat an interface in a full atomic level and by that they are a valuable complementary technique for experiment and theory. In this paper, different methods for the calculation of an interfacial tension by computer simulations are described and compared. The most commonly used method for the interfacial tension calculation was developed by Kirkwood-Buff. It is based on the mechanical route definition. This approach uses normal and tangential pressure components of the pressure tensor. The interfacial tension can be also evaluated through its thermodynamic definition. The method of Bennett defines the interfacial tension as the free energy difference of two (or more) systems relative to the difference in interfacial areas. The "test-area" method is based upon the perturbation formalism. The test state is obtained from an infinitesimal change of the surface area of the reference system. The third method based on the thermodynamic route used to evaluate the interfacial tension is thought as an expanded ensemble simulation where two systems with different free energy and the interfacial area are connected by a discrete chain of intermediate subsystems. The next approach is based on the capillary wave theory formalism which provides a relationship between the surface tension and the wave width due the capillarity broadening. Interfacial tension may be also computed from the square gradient theory which is based on the expansion of the Hemholtz free energy in the Taylor series around the homogeneous state with the assumption that the molecular gradients in the interface are small compared to intermolecular distance. The theoretical basis, application and results of computer simulations of each method are presented. Aa accuracy of the methods in different simulation methodologies and systems is compared.

Keywords: interfacial tension, computer simulations, Kirkwood-Buff method, Bennetts method, test-area method, expanded ensemble simulation, capillary wave theory, square gradient theory


Wiadomości Chemiczne, 2014, 68, 257.
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METHODS USED TO VIZUALIZE LATENT FINGERPRINTS

Emilia Karolina Kołek-Kaczanowska, Joanna Kreczko, Zbigniew Maćkiewicz

Wydział Chemii, Pracownia Chemii Polipeptydów, Uniwersytet Gdański, ul. Wita Stwosza 63, 80-952 Gdańsk


Dactyloscopy as one of the branches of forensic science deals with fingerprints identification of the individual human being. Fingerprints are in general invisible, therefore in order to set about the identification, we have to make them evident. To reveal hidden fingerprints, criminological technology uses physical methods, chemical reactions and even some biological processes. In this review, we present a set of methods that is being used in criminology to reveal fingerprints and other hidden traces.

In search for potential fingerprints, objects are exposed to natural and artificial light sources since visual methods are most commonly used by criminology technicians. Further methods for revealing fingerprints are selected on the basis of type of surface, the trace was left on, and the substance forming the fingerprint. In his article we present the set of methods, commonly used to reveal fingerprints, featuring physical, chemical and physicochemical approaches [6].

Chemical methods: DFO, 1,2-IND and Ninhydin used for revealing fingerprints on absorptive surfaces, Amido Black, Hungarian Red, DAB and LCV used for detecting bloody fingerprints, DMAC used for revealing fingerprints on temperature-felt papers, RTX dioxide of ruthenium used to absorptive and nonabsorptive surfaces [9, 11, 14, 19, 22, 24, 26, 28, 30].

Next, we present physical methods among others optical methods which are helpful in revealing fingerprints for the naked eye and (if needed) enlarging optical devices. To achieve acceptable visibility, criminologists use various kinds of lamps and filters. Subsequently we present methods based on adhesion, that are based on adjoining the powder or suspension to sudoral-fatty substance. We present here methods based on the use of dactyloscopic powders, crystal violet which is appearing in the form of dark-green powder , SPR (Small Particle Reagent) - suspension of black MoS2 powder, Sticky-side Powder which composition is accessing iron oxide and aluminum, Wet Powder Black, composed of iron oxide and Wet Powder White (titanium dioxide). Tape-Glo (ready-made red-orange solution), Sudan Black B (in the solid state it is a powder of the black colour), Liquid-drox (yellow solution), fluorescent dyes: Ardrox P133D, Safranin O, chelate of europium and Basic Yellow 40 [31, 34-38].

The other methods are physicochemical methods: cyanoacrylate, iodine, physical developer and multi metal deposition [42, 45, 46].

As a result of technological development newer methods of visualizing latent fingerprints appear, replacing those previously used. Improvement of the methods of revealing latent fingerprints leads to better readability and in effect, makes police work easier.

Keywords: fingerprints, dactyloscopy, revealing, visualization


Wiadomości Chemiczne, 2014, 68, 279.
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CHARACTERISTIC OF THE ENDOGENOUS ENKEPHALIN DEGRADING ENZYMES INHIBITORS

Małgorzata Sobocińska*, Zbigniew Maćkiewicz

Pracownia Chemii Polipeptydów, Wydział Chemii, Uniwersytet Gdański, ul. Wita Stwosza 63 80-308 Gdańsk
*e-mail: mk.sobocinska@gmail.com


Management of acute and chronic pain has always been a key area of clinical research. Pain and stress stimulation may cause an increase in the level of endogenous opioids in the body. Endogenous enkephalins activate opioid receptors in the brain, leading to the analgesic effect. Enkephalinases inactivate endogenous opioids, abolishing their activity. Enkephalin degrading enzyme inhibitors (EIs) in turn inhibit these enzymes, preventing them from degrading endogenous enkephalins what leads to analgesia. The enkephalin degrading enzyme inhibitors seem to be promising analgesic agents [2]. Analgesic effect of EIs has been discovered recently and their therapeutic potential has not been effectively investigated yet. The main advantage of enkephalinase inhibitors is that they do not show adverse effects characteristic for opioids. EIs play an important role in modulating nociception, so they are potential agents for the treatment of acute and chronic pain. They often possess also additional antidiarrheal, antidepressant and anticancer properties [3]. The potential EIs targets appear to be aminopeptidase N (APN), dipeptidyl peptidase III (DPP III), angiotensin-converting enzyme (ACE) and neutral endopeptidase (NEP) [4].

EIs may be broadly classified as endogenous and those that are obtained synthetically [4]. The purpose of this work is to present a review of endogenous enkephalinase inhibitors: sialorphin, opiorphin, and spinorphin.

Sialorphin (Gln-His-Asn-Pro-Arg) is synthesized predominantly in the submandibular gland and prostate of adult rats in response to androgen steroids and is released locally and systemically in response to stress. Sialorphin protects endogenous enkephalins released after nociceptive stimuli by inhibiting NEP in vivo. Sialorphin prevents spinal and renal NEP from breaking down substance P and Met-enkephalin in vitro. Sialorphin suppressed pain sensation for both chemical-induced inflammation and acute physical pain [8, 9, 12].

Opiorphin (Gln-Arg-Phe-Ser-Arg) is an endogenous chemical compound first isolated from human saliva. Opiorphin is a natural analgesic. Opiorphin protects enkephalins from degradation by human neutral endopeptidase and aminopeptidase N. Opiorphin is closely related to the rat sialorphin peptide [12, 13, 19].

Spinorphin (Leu-Val-Val-Tyr-Pro-Trp-Thr) has been isolated from the bovine spinal cord as an endogenous inhibitor of enkephalin - degrading enzymes. Spinorphin is an antagonist of the P2X3 receptor and a weak partial agonist/antagonist of the FP1 receptor [24, 25, 26].

Keywords: endogenous enkephalin degrading enzymes inhibitors, opioid, peptides, pain, analgesicagents


Wiadomości Chemiczne, 2014, 68, 317.
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OKRUCHY XXXI. ANTONI GRABOWSKI - CHEMIK-ESPERANTYSTA

Ignacy Z. Siemion , Kazimiera Lukjan

Wydział Chemii Uniwersytetu Wrocławskiego, ul. F.Joliot-Curie 14, 50-383 Wrocław



Wiadomości Chemiczne, 2014, 68, 329.
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CRYSTALLOGRAPHY IN POLAND

Zofia Kosturkiewicz

Wydział Chemii UAM, ul. Umultowska 89b, 61-614 Poznań
e-mail: zkostur@amu.edu.pl


The history and present state of crystallography in Poland have been presented. The beginnings of crystallography are connected with mineralogy. In 1953 crystallography was introduced as an obligatory subject in university chemistry curricula, producing new crystallography laboratories, and separating crystallography from mineralogy. In 1956 Wł. Trzebiatowski initiated at the Technical University of Wrocław the annual X-Ray Crystallographic Meetings, which became the "Crystallographic Meetings" of the Polish Academy of Sciences. In 2013 the 55th such Meeting took place. Committee of Crystallography PAS consists of five Sections: 1/ Structural Analysis (crystal chemistry), 2/ Applied Crystallography (polycrystalline materials), 3/ Crystal Physics 4/ Crystal Growth and 5/ Protein Crystallography. The present state of Polish crystallography is described in these five segments. A paragraph is dedicated to the role of Polish crystallographers in the North American science.

Keywords: mineralogy, history of crystallography, Polish crystallographic laboratories


Wiadomości Chemiczne, 2014, 68, 357.
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STRUCTURAL TRANSFORMATIONS IN CRYSTALS INDUCED BY PHOTOCHEMICAL REACTIONS

Ilona Turowska-Tyrk*, Julia Bąkowicz

Wydział Chemiczny, Politechnika Wrocławska, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław
*e-mail: ilona.turowska-tyrk@pwr.edu.pl


Structural changes induced in crystals by photochemical reactions were presented. The changes concern: a) the distances between neighbouring reactant molecules and their mutual orientation in the case of intermolecular reactions, b) the distances and angles between fragments of a molecule for intramolecular reactions, c) the position of molecules in crystals, d) geometry of hydrogen bonds, e) cell constants, and f) the content of product molecules in crystals. For most intramolecular reactions, the distances between reactive atoms are constant for a long time in phototransformation and decrease rapidly at its end (Figs. 3 and 5). In the case of intermolecular reactions, the distances between reactive atoms of reactant molecules decrease linearly along with the phototransformation of crystals (Fig. 7). Additionally, unreacted molecules become, to a certain degree, similar to product molecules in terms of their shape (Figs, 4 and 8). Reactant and product molecules do not assume a fixed place in crystals. Product molecules change their orientation towards that of which is observed in a pure product crystal and reactant molecules gradually move away from the position they took in pure reactant crystals. All this has an influence on the geometry of hydrogen bonds existing in crystals (Fig. 9). The above-mentioned structural transformations find their expression in values of cell constants (Fig. 10). The factors influencing the photoreactivity of molecules in crystals were also described. Knowledge of crystal and molecular structures of partly reacted crystals, determined thanks to X-ray structure analysis which is a branch of crystallography, reveals the behaviour of molecules in crystals in which photochemical reactions proceed and helps to understand a pathway of these reactions.

Keywords: photochemical reactions in crystals, crystal and molecular structures, structural changes, X-ray structure analysis, crystallography


Wiadomości Chemiczne, 2014, 68, 381.
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ELECTRON DENSITY DISTRIBUTION IN CRYSTALS OR HOW TO SEE THE DETAILS OF THE ELECTRONIC STRUCTURE OF MOLECULES

Maciej Kubicki

Wydział Chemii, Uniwersytet im. Adama Mickiewicza w Poznaniu, ul. Umultowska 89b, 61-614 Poznań
e-mail: mkubicki@amu.edu.pl


X-ray structural analysis might be regarded as a method of visualizing molecules as they appear in the crystals. The model, which is conventionally and universally used in this method, the Independent Atom Model (IAM) assumes that the electron density distribution, which scatters the X-rays is built of the spherically-symmetrical, neutral atoms. This model is responsible for the unprecedented success of X-ray structural analysis, which reflects in about one million crystal structures (i.e. the sets coordinates of the atoms constituting the molecules) deposited in the various databanks (cf. Fig. 1), and in the speed and accuracy which the method has reached. In principle, in few hours one can get the complete information about the crystal structure.

But this success is accompanied by negligence of the scientific virtue hidden beyond the IAM. In fact, it was known from the very beginning of the X-ray diffraction studies by von Laue and Braggs, that some fine details of the electron density distribution should be available. The technological advance (four-circle diffractometers, powerful X-ray sources, fast computers etc.) caused that in 1960's the time was ripe for the development of the experimental studies of details of electron density distribution in the crystals, beyond the IAM. The early experiments by Coppens and co-workers proved that this information - about the electron density transferred to the covalent bonds, lone pairs, even intermolecular interactions - can actually be obtained and analyzed (Fig. 2). The need for the model which could be used in the least-squares procedure led to the formulation of so-called pseudoatom models, including the most popular till now, Hansen-Coppens model (eq. 2) in which the aspherical part is described in terms of real spherical harmonics.

In this paper, the basics of the electron density studies is described in some detail, including the step-by-step description of a typical procedure from the experiment to the final steps of refinement. An example of the analysis of the high-resolution structure of 1,2-dimethyl-4-nitro-5-morpholine-imidazole hydrate is used to show an application of this method in studying the intermolecular interactions, including weak C-H···O and C-H···N hydrogen bonds. It is shown that the multipolar model is able to deliver more informations than the promolecular model with spherically symmetrical electron distributions.

Keywords: electron density distribution; multipolar model; intermolecular interactions; 4-nitroimidazole derivatives


Wiadomości Chemiczne, 2014, 68, 403.
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THE IMPORTANCE AND EXAMPLES OF APPLICATION OF ASPHERICAL PSEUDOATOM DATABANKS IN SMALL-MOLECULE CRYSTALLOGRAPHY AND THEIR POTENTIAL USE IN MAKROMOLECULAR CRYSTALLOGRAPHY

Paulina Maria Dominiak

Wydział Chemii, Uniwersytet Warszawski, ul. Pasteura 1, 02-093 Warszawa
e-mail: pdomin@chem.uw.edu.pl


X-rays are diffracted by the electron density of crystals. Thus, the correct analysis of a single crystal X-ray diffraction pattern can provide information about the distribution of the electron density. How precise and accurate the information could be is largely determined by the resolution of the data collected. The majority of X-ray diffraction data is collected at and below the standard resolution, dmin = 0.84 Å. Before the development of pseudoatom databases, such resolution permitted to carry out X-ray refinement only with the use of simple model of electron density called the Independent Atom Model (IAM). In the IAM, individual atoms are represented by the spherically averaged electron density distributions obtained by theoretical methods for isolated atoms in the ground state. The IAM does not take into account changes in the density distribution of individual atoms caused by such phenomena as chemical bond formation, charge transfer, lone electron pairs, etc. Only the geometrical information of the crystal structure is obtained from the IAM refinement.

A more physical model has been introduced in which an atom is represented as a finite spherical harmonic expansion of the electron density around each atomic center and is called a pseudoatom. Such definition allows the pseudoatom electron density to be individually adjusted (by changing values of pseudoatom parameters) to account for density departure from spherical and neutral model. However, to refine pseudoatom parameters with experimental data subatomic resolution is required.

It has been shown that the values of pseudoatom parameters are almost identical for atoms in similar chemical environments, i.e. atoms having similar local topology of connecting chemical bonds. Therefore it was possible to build a databank of different types of pseudoatoms and to use the bank to generate the Transferable Aspherical Atom Model (TAAM) for any organic molecule, including proteins and nucleic acids. There are three different pseudoatom databanks being developed: ELMAM2, GID and UBDB. They differ by the source of pseudoatom parameters and by the way how atom types are defined. Replacement of the IAM model by the TAAM in the refinement procedure of standard diffraction data leads to more accurate geometrical information and provide access to quantitative estimation of the electron density distribution and properties derived from it (dipole moment, electrostatic potential, etc.) for molecules in a crystalline environment.

The review summarizes the research on the verification and application of pseudoatom databases.

Keywords: aspherical atomic scattering factors, electron density, X-ray diffraction data, crystal structure


Wiadomości Chemiczne, 2014, 68, 429.
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THE USE OF TOPOLOGICAL ANALYSIS OF ELECTRON DENSITY IN CHARACTERIZATION OF NONCOVALENT INTERACTIONS

Barbara Bankiewicz1,2, Agnieszka Rybarczyk-Pirek1, Magdalena Małecka1, Małgorzata Domagała1, Marcin Palusiak1,*

1 Katedra Chemii Teoretycznej i Strukturalnej, Wydział Chemii, Uniwersytet Łódzki, ul. Pomorska 163/165, 90-236 Łódź
2 Zakład Chemii Teoretycznej, Instytut Chemii, Uniwersytet w Białymstoku, ul. Hurtowa 1, 15-339 Białystok
*e-mail: marcinp@uni.lodz.pl


All atomic and molecular properties are governed by an electron density distribution. Thus, the methods that deal with an analysis of the electron density distribution should have a particular appeal for chemists and help to understand the electron structure of molecules. The Quantum Theory of Atoms in Molecules gives the unique opportunity to have an insight into a region (e.g., an atom) of a given system (e.g. a molecule), delivering partitioning scheme which is defined explicitly within the rigorous quantum theory, from one side, and is applicable for experimentally available set of observables, from the other side. In that way QTAIM delivers a chemist a theoretical tool to study a small part of a molecule only, instead of dealing with the total energy of a whole system. In consequence, QTAIM has become one of the most powerful utilities of modern chemistry, forming a bridge between advanced theoretical and experimental techniques. In particular the properties of the electron density function in the so-called bond critical point (BCP, the (3, -1) saddle point on electron density curvature) seem to be valuable information for chemists, since it was proven in many papers that the chemical bonding can be characterized and classified on the basis of electron density characteristics measured in BCPs .

In this review we firstly give a brief introduction to the theory, explaining most basic terms and dependences. In the main part of the review we discuss application of QTAIM in the qualitative and quantitative analysis of several various noncovalent interactions, focusing readers attention on such aspects as classification of interactions and interaction energy assessment. Both theoretical and experimental approaches are taken into account. We also discuss extensions of QTAIM to the analysis of the so called source function - the method which additionally enlarge interpretative possibilities of its parent theory.

Finally, we give some examples which perhaps escape a rigorous QTAIM definition of chemical bonding. We acquaint the potential reader with arguments being pro- and against the QTAIM-based deterministic model of a chemical bond.

Keywords: Quantum Theory of Atoms in Molecules, electron density, topological analysis, chemical bonding, noncovalent bonding


Wiadomości Chemiczne, 2014, 68, 457.
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HIGH-PRESSURE CRYSTALLOGRAPHY: HOW TO SEE THE STRUCTURE OF MATERIALS... DEEPER

Anna Olejniczak, Kamil Dziubek, Damian Paliwoda, Witold Zieliński, Marcin Podsiadło, Andrzej Katrusiak*

Wydział Chemii, Uniwersytet im. Adama Mickiewicza, ul. Umultowska 89b, 61-614 Poznań
*e-mail: katran@amu.edu.pl


During recent decades the number of high-pressure crystallographic studies has rapidly increased. This has been possible owing to the diamond-anvil cell, a small, relatively cheap and save apparatus breaking all records of static pressure. The diamond-anvil cell is suitable for diffraction structural studies, optical and IR spectroscopy and many other types of physical measurements; it can be also applied as a microscopic chemical reaction chamber. High pressure is now often used for synthesizing super-hard materials, new polymorphs and solvates with unique properties required in high-tech applications as well as in food processing and pharmaceutical industry.

Keywords: high pressure, diffraction studies, diamond-anvil cell, polymorphism


Wiadomości Chemiczne, 2014, 68, 487.
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NEW METHODS IN INVESTIGATIONS OF POLYCRYSTALLINE MATERIALS

Wiesław Łasocha1,2, Katarzyna Luberda-Durnaś2 1 Zakład Krystalochemii i Krystalofizyki, Wydział Chemii Uniwersytet Jagielloński, ul. Ingardena 3, 30-060 Kraków
2 Instytut Katalizy i Fizykochemii Powierzchni im. J. Habera, Polska Akademia Nauk ul. Niezapominajek 8, 30-239 Kraków
e-mail: lasocha@chemia.uj.edu.pl


In this chapter, information on good laboratory practice in the field of structural powder diffractometry has been collected. The authors attempt to describe how to plan a measurement, how to find the cell parameters, how to build a model of the structure, and how to refine and verify it. There are many methods and procedures which lead to solving a crystal structure. However, the experience of recent years shows that, in the case of many materials, an investigator has to attempt the problem of structure solution using many different methods. The software is easily available (from 'trial and error' or classic to sophisticated modern approaches), as is a lot of good equipment. On the other hand, the complexity of the structures studied using powder diffraction methods is continually increasing.

No description of any methods of research other than diffraction techniques is presented. We have also focused on polycrystalline materials. Amorphous substances and methods using the formalism of 'pair distribution functions' are beyond the scope of this paper.

New methods of structural studies (including algorithms from research described in the literature, even if their applicability has been relatively slight) were treated with particular attention.

In addition to the description of methods, we also collected some useful (in our opinion) information about available software and crystallographic databases.

Keywords: powder diffractometry, indexing of diffraction patterns, powder diffraction pattern decomposition, structure refinement using the Rietveld method, new methods of structural studies


Wiadomości Chemiczne, 2014, 68, 507.
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FROM MOLECULAR RECOGNITION TO RACEMIC RESOLUTION BY FRACTIONAL CRYSTALLIZATION OF DIASTEREOMERIC SALTS

Agata Białońska

Wydział Chemii Uniwersytetu Wrocławskiego, ul. F. Joliot-Curie 14, 50-383 Wrocław
e-mail: agata.bialonska@chem.uni.wroc.pl


Synthesis and isolation of enantiopure compounds remains an important challenge in medicinal, pharmaceutical, alimentary as well as material chemistry. Amongst many methods leading to enantiopure compounds, formation and fractional crystallization of diastereomeric salts of an enantiopure resolving agent is the most popular one. Since its discovery many years went by, and yet it has been performed by the trial and error method.

Selection of the suitable resolving agent is crucial for racemic resolution efficiency. Hence, this review is concerned with common features of crystal structures of salts, in which resolving agents, frequently used for separation of racemic acids, are involved. Among them, there are crystal structures of salts of primary, secondary and tertiary chiral amines (1-arylethylamines, ephedrine, pseudoephedrine, deoxyephedrine, chinine, chinidine, cinchonine, cinchonidine, strychnine and brucine). In most of them, cations and anions are involved in characteristic systems of hydrogen bonds leading to formation of cationic-anionic self-assemblies. In this respect, brucine and strychnine appear as unique, because presence of anions usually does not affect formation of common cationic self-assemblies stabilized by weak hydrophobic interactions.

Comparison of the common structural motifs indicates different factors being crucial in molecular recognition and in diastereomeric diversification. Formation of common hydrogen bonded cationic-anionic self-assemblies plays a dominant role in molecular recognition of a given acid by most of the studied amines. In turn, formation of common cationic self-assemblies stabilized by hydrophobic interaction plays a crucial role in molecular recognition of a given acid by brucine or strychnine.

Diastereomeric diversification can be realized in various ways. In extreme cases, when molecular recognition in crystals of particular diastereomeric salts is similar, diastereomeric diversification is governed by different factors, depending on factors governing molecular recognition. Hydrophobic interactions play an important role in diastereomeric diversification when molecular recognition is governed by hydrogen bonds. In turn, when molecular recognition is governed by hydrophobic interactions, different hydrogen bond systems in crystals of particular salts are responsible for their diastereomeric deversification.

Keywords: racemic resolution, diastereomeric salts, resolving agent, diastereomeric diversification, molecular recognition


Wiadomości Chemiczne, 2014, 68, 545.
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STRUCTURE AND PATHOGENESIS OF DISORDERS RELEATED TO CNG REPEATS

Agnieszka Kiliszek, Wojciech Rypniewski*

Instytut Chemii Bioorganicznej Polskiej Akademii Nauk, ul. Noskowskiego 12/14, 61-704 Poznań
*e-mail: wojtekr@ibch.poznan.pl


CNG repeats (N stands for one of the four natural nucleotides) are a special class of microsatellite sequences of the human genome. They are most often found in exons, in their coding parts as well as in the 5' or 3' untranslated regions. Characteristic frequencies of their occurrence within the different parts of the genes suggest that they play a functional role. The number of CNG repeats in a block is usually below 30 but it can undergo abnormal expansion leading to the development of one of approximately 20 neurological diseases known as TREDs (Triplet Repeat Expansion Disorders). One model of pathogenesis proposes that the toxic factor is mRNA containing an expanded run of CNG repeats. The anomaly results in aberrant alternative splicing and/or accumulation of the RNA in the cell nucleus, followed by a sequestration of important regulatory proteins and formation of RNA/protein aggregates known as nuclear foci. This is accompanied by a deregulation of vital cellular processes.

In this paper we have focused on crystallographic studies of RNA oligomers with embedded CNG repeats. We describe briefly diseases associated with each type of repeat and present the crystal structures. All the CNG repeats form stable "hairpins" consisting of a small apical loop and a long double-stranded stem, in which the non-canonical N-N pairs are flanked by the standard C-G and G-C pairs. All CNG repeats form duplexes of type A, characteristic of RNA, but with local deviations from the typical geometry (Fig. 1). The duplexes are stabilised by the strong C-G and G-C Watson-Crick interactions, while the N-N pairs are accommodated within the helical context, each in a characteristic way (Fig. 2). The U-U pairs tend to form just one hydrogen bond, instead of two observed in other contexts. The interactions within the C-C pairs are even weaker, via one very weak hydrogen bond or none. On the other hand, accommodation of the bulky A-A pairs involves pushing the purine rings towards the major groove while in the G-G pairs one of the guanosine residues flips to a syn conformation. The unrealised hydrogen-bonding potential of the N-N pairs is externalised into the major and the minor grooves and can be assessed through interactions with ordered water molecules and other small ligands. The N-N pairs are associated with local distortions of the A-helix (Fig. 1). All the CNG repeats show a characteristic striped pattern of surface electrostatic potential in the minor groove (Fig. 3). Assessment of the different CNG structures allows us to identify the characteristic and the common features (Tab. 1).

Keywords: RNA crystal structure, TREDs, CNG repeats


Wiadomości Chemiczne, 2014, 68, 563.
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HIGH RESOLUTION CRYSTALLOGRAPHY OF MACROMOLECULES

Mirosław Gilski

Zakład Krystalografii, Wydział Chemii UAM, ul. Grunwaldzka 6, 60-780 Poznań Centrum Badań Biokrystalograficznych, Instytut Chemii Bioorganicznej PAN, ul. Noskowskiego 12/14, 61-704 Poznań
e-mail: mirek@amu.edu.pl


The recent developments and availability of modern third-generation synchrotron radiation facilities have a huge impact on macromolecular X-ray crystallography. In connection with a number of methodological improvements and new crystallographic software ranging from data processing to refinement, a unique opportunity has arisen to determine the macromolecular structures with unprecedented high resolution and quality, at a level traditionally reserved for small molecules.

At this resolution, individual atoms are clearly resolved and fine details of the structures become visible directly in the electron density maps.

The great importance of such structures is the possibility of having broader insights into macromolecule function. At very high resolution, hydrogen atoms can be seen in electron density maps and the detailed information about the protonation states of catalytically important residues can be studied, what often is critical for full understanding of enzymatic reactions.

Atomic resolution gives the opportunity for clear definition of multiple conformations, although the proportion of disordered residues is higher at higher resolution, and the disorder is seen as distinct alternative conformations.

Water in macromolecular crystal plays an important role in macromolecule's function and stabilization. Ultrahigh resolution data allows to refine water molecules with anisotropic displacement parameters and refine them with fractional occupancies. In this situation analyzing the subtle hydrogen bond network, involving precisely located water molecules, is possible.

Atomic resolution structures can be refined without or with only very weak stereochemical restraints. Macromolecular models refined at ultrahigh resolutions, for well ordered structures, can be used for validation and improvement of stereochemical restraint libraries, commonly used during refinement of macromolecular structures.

Keywords: macromolecular crystallography, atomic resolution structures, stereochemical restraints, charge density


Wiadomości Chemiczne, 2014, 68, 587.
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APPLICATIONS OF CLICK CHEMISTRY IN MODIFICATION OF NUCLEOSIDES AND OLIGONUCLEOTIDES

Michał Gładysz*, Jan Milecki

Uniwersytet im. Adama Mickiewicza w Poznaniu, Wydział Chemii, Pracownia Spektrochemii Organicznej, ul. Umultowska 89b, 61-614 Poznań
*e-mail: migladysz@amu.edu.pl


Since the year 2001 new ideology of clean and simple synthesis in organic chemistry has been established. The outstanding scientists Meldal and Sharpless presented their concepts of Click Chemistry. Among the reactions chosen for this concept the reaction of Copper(I) Catalyzed Alkyne-Azide Cycloaddition (CuAAC) became the most popular one. It is the basis of syntheses employed for building blocks synthesis in medicinal chemistry and material science. Libraries of potentially pharmacologically active anticancer and antivirus compounds possessing neutral triazol linkage could be easily obtained.

Remarkable efficiency of CuAAC reaction influenced on DNA- and RNA- based synthesis of novel oligonucleotides derivatives. Many of nucleic acid molecular modifications found applications in enzymatic transformation, nucleic acid hybridization, molecular tagging and gene silencing. The CuAAC reaction allows for introducing modifications into practically every region of nucleoside/nucleotide/oligonucleotide. This includes versatile modifications of the base moiety both aiming at the base pairing ability or specific labeling of the nucleoside unit. Different conjugates (bio-, fluorescent-, affinity- or spin labels) are being attached to the base part of the nucleic acid taking advantage of the presence of azide or alkyne substituents, which can be installed without great difficulty.

Labeling at the sugar part of the nucleoside can be realized at the position 2', 3' or 5', the latter two giving rise to the end-labeled oligonucleotides and the 2' position serving as the attachment point for labeling inside the oligonucleotide chain. These kind of nucleic acid modifications are very promising. Versatility of CuAAC reactions is demonstrated by numerous examples of introducing modifications into practically every reactive site of the nucleotide/oligonucleotide molecule. The review systematically presents application of the "click" technique for modification of nitrogenous base, sugar or pseudosugar moiety or phosphorus center. Possibility of creating new kind of chain linkage, devoid of negative charge and nuclease resistant is also shown. This allows to design a new class of nucleic acid analogues, similar in its DNA-mimicking properties to PNA's.

Keywords: Click Chemistry, CuAAC, nucleosides modifications, oligonucleotides, DNA, RNA


Wiadomości Chemiczne, 2014, 68, 617.
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MALDI - METHOD FOR USE IN STRUCTURAL ANALYSIS OF POLYMERS

Beata Swinarew1*, Andrzej Szymon Swinarew2

1 Instytut Inżynierii Materiałów Polimerowych i Barwników, Oddział Farb i Tworzyw, 44-100 Gliwice
*e-mail: b.swinarew@impib.pl
2 Instytut Nauki o Materiałach, Uniwersytet Śląski, 40-007 Katowice


Polymers as one of the fastest growing groups of widespread use of synthetic materials are characterized by a great diversity of structures. Structural characterization of polymers generally includes: an assessment of the average molecular weight (Mn) and the molar mass distribution (PD) to determine the structure of repeating units (mers) sequence analysis of the copolymer, identification of the end groups, the detection and identification of contaminants and substances present in the composition of the polymer asa dopant. Modern mass spectrometry (MS) offers the opportunity to study the smallest structural details of macromolecular materials [1-10].

Because of the variety of potential structures of polymer analysis process is to answer a few questions by a certain pattern. The first step is to determine the chemical structure of the polymer backbone. The second step is to identify whether the chains have branching points and define the degree of branching. The third important step is to correct end groups identification, also for the detection of cyclic oligomers that can be present.

The structural studies can be made by mass spectrometer using reflectron mode. In the essence, the method involves three steps. The first analysis is performed with standard mass spectrum of the sample. Then the precursor ion (parent ion) is selected, which is subjected to further analysis by MS changed voltages and reflectron mode.

This paper aims to present the issues related to the detailed analysis and characterization of polymeric materials produced on a large scale. Before, for materials such as poly(propylene), poly(ethylene), poly(styrene), polycarbonate, etc., increasing demands on the mechanical and technological parameters were placed. Maintaining a high level of products is associated with a very rigorous process control of the manufacturing, processing and transportation at every stage. The optimal tool for the structural characteristics of these polymeric materials is the defense technique MALDI-TOF MS (Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometer) due to its versatility, speed and extremely high precision. Below, we present some aspects of MALDI MS analysis of polymeric materials and composites.

Note, that the following literature review focuses on the recent developments in the field of preparation of the samples, to achieve high mass resolution, the identification of polymers and copolymers, the accuracy of the molar mass determination and the identification of functional end groups, sequence analysis of the copolymer.

Keywords: polymers, matrix-assisted laser desorption ionization mass spectrometry, copolymers, polymer degradation


Wiadomości Chemiczne, 2014, 68, 645.
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ISOFALVONES - STRUCTURE, BIOLOGICAL ACTIVITY AND DETERMINATION BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Ilona Bachanek, Marian Czauderna

Instytut Fizjologii i Żywienia Zwierząt im. Jana Kielanowskiego, Polska Akademia Nauk, ul. Instytucka 3, 05-110 Jabłonna
e-mail: i.bachanek@ifzz.pan.pl


Isoflavones are a subclass of flavonoids and are also described as phytoestrogen compounds, since they exhibit estrogenic activity (similar effects to estradiol hormones). The basic characteristics of isoflavone structure is a flavone nucleus, composed of two benzene rings (A and B) linked to a heterocyclic ring C (Fig. 1). The benzene ring B position is the basis for the categorization of a flavanoid class (position 2) and a isoflavonoid class (position 3) [8]. Isoflavones are classified according to substitutions. The glucoside forms can be esterified at the 6''-O-position of the glucose ring with malonyl or acetyl groups forming another compounds.

In food and plants, flavonoids exist primarily as 3-O-glycosides and polymers [14]. Isoflavonoids are a group of chemical compounds which is widely distributed in the vegetable world. Their biological activity has found remarkable pharmaceutical, therapeutic, dietary and nutritional applications. The structure of phytoestrogens enables them to bind to the estrogen receptors (ERs), they are similar to 17β-estradiol, contain an aromatic ring with hydroxyl group and have the binding affinity to both estrogen. In addition, isoflavones interact with the metabolism of steroid hormones. Recently, they have come into focus of interest due to several reports about their positive effect on human health, in particular prevention of hormone-dependent cancers, cardiovascular diseases, osteoporosis, adverse menopausal manifestations and age-related cognitive decline.

To identify the potential health benefits associated with the consumption of isoflavones, it is of critical importance to have high-quality and comprehensive data. To this end, adequate analytical methodologies are essential for a reliable and exact identification as well as for quantification. Moreover, methodologies and techniques used need to keep up with technology to improve the performance in terms of resolution, efficiency, precision, reproducibility and speed, allowing a proportionate increase in the amount and quality of information gathered [7].

Common methods for the extraction of isoflavones from soybeans and soy products include organic solvent extraction with aqueous methanol, ethanol or acetonitrile, using simple mixing, ultra-sonification or refluxing techniques [24].

The application of micro-scale and nano-scale extraction and separation techniques is the most likely future development, resulting in quick, sensitive analytical methods for sample preparation and analysis of flavonoids and their metabolites. Miniaturization, high-throughput systems utilizing new sorbents and automation of chromatographic systems are of great interest in clinical, pharmaceutical, environmental and food fields. The most used analysis technique for the quantification of isoflavones in solid samples is, with no doubt, reversed-phase HPLC using C18 based columns with water and methanol or acetonitrile containing small amounts of acid as a mobile phase [7].

Keywords: isoflavone, sample preparation, determination, high performance liquid chromatography (HPLC)


Wiadomości Chemiczne, 2014, 68, 663.
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PECTINS - OCCURRENCE, CHEMICAL CONSTITUTION AND PHYSICOCHEMICAL PROPERTIES

Hanna Pińkowska, Adrianna Złocińska*

Katedra Technologii Chemicznej, Wydział Inżynieryjno-Ekonomiczny, Uniwersytet Ekonomiczny we Wrocławiu, ul. Komandorska 118/120, 53-345 Wrocław
*e-mail: adrianna.zlocinska@ue.wroc.pl


Pectins are important polysaccharide structure constituents of plant middle lamellae and primary cell walls ensuring their water retention performance and the pH stability [1, 11]. Due to the high gelling, stabilising and thickening properties they are widely used in the food and pharmaceutical industry [3, 9]. Commercial pectin substances are extracted from the waste material, especially citrus peels (from orange, grapefruit, lemon and lime fruit), apple pomace and sugar beet pulp. The high concentration of pectins is found also in other fruits and vegetables, mainly soy hull, mango peels and sunflower heads [3, 11, 12, 14].

The properties of pectins result mainly from their chemical structure. The pectin backbone is primarily composed of homogalacturonan (Fig. 1), which is a linear polymer consisting of α-1→4-linked D-galacturonic acid units, partially methyl-esterified or O-acetylated [3, 9]. Other structural elements of pectins are rhamnogalacturonan type I (Fig. 2) and type II (Fig. 3), xylogalacturonan (Fig. 5), arabinan (Fig. 6), arabinogalactan type I (Fig. 7) and type II (Fig. 8) [3, 5, 8].

The gelling property of pectins depends on the degree of methyl esterification of their carboxyl groups (DE). According to this parameter there are high ester pectins (DE > 50) and low ester pectins (DE < 50). The high ester pectins form gels in the presence of high sugar concentrations exceeding 55% and pH lower than 3.5, while in the case of low ester pectins the gelation process occurs even at low concentrations of sugar but the presence of divalent ions is required (e.g. calcium) [18, 21].

The aim of this study was a review of the available literature regarding the sources of pectins, their types, chemical structure and physicochemical properties.

Key words: high ester pectins, low ester pectins, homogalacturonan, rhamnogalacturonan, xylogalacturonan, gelation


Wiadomości Chemiczne, 2014, 68, 685.
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GLYCIDYL FATTY ACID ESTERS AND MONO-3-CHLOROPROPANE-1,2-DIOL FATTY ACID ESTERS - NEW CONTAMINATION IN EDIBLE OILS

Magda Aniołowska*, Agnieszka Kita

Uniwersytet Przyrodniczy we Wrocławiu, Katedra Technologii Rolnej i Przechowalnictwa, ul. Chełmońskiego 37/41, 51-630, Wrocław
*e-mail: magda.aniolowska@wnoz.up.wroc.pl


The aim of the review was to characterize and describe the physicochemical properties and methods for the determination of two types of compounds: 3-monochloropropane-1,2-diol fatty acids esters (3-MCPD esters) and glycidyl fatty acids esters (GE) - new contaminants of food products, including vegetable fats.

This paper describes their structure, several possible mechanisms of reactions occurring during the refining of edible oils, leading to an increase of their content in the final product. It is suggested that these compounds are formed from acylglycerols, under the influence of high temperature [9]. The emphasis was put on the toxicity of the products of their deesterification-free 3-monochloropropane-1,2-diol (3-MCPD) and glycidol. Glycidol is genotoxic and has an effect on gene mutations and unscheduled DNA synthesis [17]. 3-MCPD is defined by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) as a genotoxic carcinogen [6, 19]. There are three transformation tracks leading to increased levels of 3-MCPD in foods: from 3-MCPD esters, GE and glycidol [14, 15]. The content of 3-MCPD esters and GE in food products was characterized and different processes involving their synthesis were described. Ways of reduction in food products regarding the aspects of raw materials as well as technology were discussed. Among refined vegetable oils, the largest quantities of 3-MCPD esters and GE were found in palm, corn and coconut oils [6, 25]. Finally, the direct and indirect methods of their determination in oils were described. There are new publications reporting on successive improvements of the existing methods for determination of 3-MCPD and its mono- and di-esters, as well as GE in edible oils [42, 43].

Unfortunately, there is still no universal determination method, which would be simple, affordable and accessible for a wider group, such as food producers, that would improve consumer safety.

Keywords: 3-MCPD fatty acid esters, glycidyl fatty acids esters, edible oils


Wiadomości Chemiczne, 2014, 68, 703.
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JERUSALEM ARTICHOKE AS A SOURCE OF VALUABLE RAW MATERIAL, ESPECIALLY FOR FOOD, PHARMACEUTICAL AND COSMETIC INDUSTRIES

Marek Chyc1, Jan Ogonowski2

1Laboratorium Analiz Specjalnych, Centrum Badań i Analiz, Grupa Azoty, ul. Kwiatkowskiego 8, 33-101 Tarnów
e-mail: marek.chyc@grupaazoty.com
2Katedra Technologii Organicznej i Procesów Rafineryjnych, Wydział Inżynierii i Technologii Chemicznej, Instytut Chemii i Technologii Organicznej,
Politechnika Krakowska, ul. Warszawska 24, 31-155 Kraków
e-mail: jogonow@pk.edu.pl


Jerusalem artichoke (Helianthus tuberosus) is a native plant to North America. Its tubers were adopted as a source of food and inulin [3]. The substances obtained from tuber, shoots and flowers can be used in medicine, cosmetics or food industry as a valuable food additive. Inulin is extracted from jerusalem artichokes. It is a white, odorless, soluble powder with a slightly sweet taste and no aftertaste. It contains a mixture of oligosaccharides and polysaccharides which are composed of fructose units connected by β (2-1) links (Fig. 1). Almost every molecule is terminated by a glucose unit. The typical total number of fructose and glucose units in inulin is 30-35. The potential of jerusalem artichoke as a source for inulin, a natural polymer that may provide dietary health benefits for obesity, diabetes, increased calcium and magnesium absorption [41-43], while promoting the growth of beneficial intestinal bacteria and several other health issues and the possible use of the crop for biofuels [17], pharmacy and cosmetics and plastics manufacturers is drawing recent interest. The health benefits of inulin provide numerous opportunities to develop functional foods in various sectors such as dairy, bakery, beverage, cereals and cereal bars, supplements, confectionary, ice cream, infant formulas, fat spreads. Inulin cannot be digested by the digestive enzymes nor broken down by the gastric acids in the human digestive system. Therefore, these non-digestible carbohydrates function as insoluble fibers. However, dietary fibers influence the consistency of stomach and bowel content, the rate of discharge from the stomach and intestines and thus the rate at which nutrients and other desirable undesirable substances are absorbed. Furthermore they have an intensive effect on human bowel movements. This makes dietary fibers an essential part of our daily menu. Several methods for inulin extraction from Jerusalem artichoke tubers have been described in this paper [7, 11, 14]. For instance, ultrafiltration can reduce the purification procedure due to convenience and rapidity (fewer steps), thus showing a promising prospect for industrial purposes [24, 29, 31].

Keywords: jerusalem artichoke, inulin, pharmaceutical industry, cosmetics industry, food industry


Wiadomości Chemiczne, 2014, 68, 721.
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O-ACYL ISOPEPTIDE METHOD IN PEPTIDE SYNTHESIS

Oliwia Frączak, Aleksandra Olma*

Instytut Chemii Organicznej, Wydział Chemiczny, Politechnika Łódzka, ul. Żeromskiego 116, 90-924 Łódź
*e-mail: aleksandra.olma@p.lodz.pl


Proteins are macromolecules that carry out most of the biochemical functions of the cell, which strongly depend on the secondary and tertiary structure, defined by the amino acid sequence of a polypeptide chain. The importance of peptides and proteins in biology and medicine inspired chemists to develop strategies for their synthesis.

The main limitation to the preparation of long peptides is their tendency to aggregation, what makes the coupling and deprotection reaction ineffective, and purification of the compounds difficult. Inter- and intramolecular interactions, hydrophobic character, the presence of multiple hydrogen bonds significantly affect the secondary structure of peptides, making further extension of the peptide chain very difficult.

Undesirable aggregation process may be disrupted by reduction of hydrophobic interactions. For this purpose, various methods are used, based on the implementation of specific modifications to the peptide chain, affecting its secondary structure. These methods include, for example, incorporation of pseudoproline building blocks [5] and proximity induced peptide ligation [6, 7].

In some cases, it is convenient to extend the amino acid side chain to form isopeptides (Fig. 1) [14-16]. Depsipeptides can be created with the natural amino acids such as cysteine, serine, threonine, tyrosine, or tryptophan. The basic requirement is the presence of β-hydroxyamino component.

The presence of a depsipeptide moiety in place of an amide bond significantly change the secondary structure of native peptide and prevents from aggregation, leading to higher yields of desired compounds [18]. In the solution phase peptide synthesis, this method is free from racemization [19]. Isodipeptide units can be successfully applied in SPPS for the synthesis of "difficult sequence"-containing peptides [19]. In this paper, many examples of effective use of O-acylisopeptides method in peptide synthesis are discussed.

Keywords: O-acyloisopeptides, ON-migration, difficult sequence-containing peptides


Wiadomości Chemiczne, 2014, 68, 735.
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ENANTIOSELECTIVE ENZYMATIC DESYMMETRIZATION CATALYZED BY OXIDOREDUCTASES. DEHYDROGENASES IN REDUCTION REACTIONS - PART I

Renata Kołodziejska*1, Aleksandra Karczmarska-Wódzka*1, Agnieszka Tafelska-Kaczmarek2, Renata Studzińska3, Marcin Wróblewski1, Beata Augustyńska1

1 Katedra i Zakład Biochemii, Collegium Medicum Uniwersytet Mikołaja Kopernika, ul. Karłowicza 24, 85-092 Bydgoszcz
2 Katedra Chemii Organicznej, Uniwersytet Mikołaja Kopernika, ul. Gagarina 7, 87-100 Toruń
3 Katedra i Zakład Chemii Organicznej, Collegium Medicum Uniwersytet Mikołaja Kopernika, ul. dr. A. Jurasza 2, 85-089 Bydgoszcz
*e-mail: Renatakol@poczta.fm *e-mail: akar@cm.umk.pl


Enzymes act as biocatalysts whether are also mediating in all anabolic and catabolic pathways, playing an extremely important role in the cells of all life forms. Catalytic potential of oxidoreductases is most commonly used in reduction reactions. Dehydrogenases and reductases catalyze the reversible desymmetrization reactions of meso and prochiral carbonyl compounds and alkenes. The oxidoreductase-catalyzed reactions require cofactors to initiate catalysis. In most cases, it is nicotinamide adenine dinucleotide (NADH) or its phosphorylated derivative (NADPH), which acts as a hydride donor. The necessity of employing expensive cofactors was, for the long time, one of the main limitations to the use of dehydrogenases. This problem was solved by developing a regeneration system of a cofactor in the reaction environment. Various systems are used for the cofactor recycling. In the case of a carbonyl compound reduction, an irreversible oxidation of formic acid to carbon dioxide is most frequently used. In this paper, selected examples of whole-cell and isolated enzymes applications in the carbonyl compound reduction are discussed. The application of baker's yeast, microorganisms and dehydrogenases in enantioselective enzymatic desymmetrization (EED) of prochiral ketones leads to a broad spectrum of chiral alcohols used as intermediates in the syntheses of many pharmaceuticals and compounds presenting a potential biological activity.

Keywords: asymmetric reduction, alcohol dehydrogenase, cofactor


Wiadomości Chemiczne, 2014, 68, 763.
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Molecularly imprinted polymers as biomimetics of metalloenzymes

Joanna Czulak*, Andrzej Trochimczuk, Anna Jakubiak-Marcinkowska

Zakład Materiałów Polimerowych i Węglowych, Wydział Chemiczny, Politechnika Wrocławska, ul. C.K. Norwida 4/6, 50-373 Wrocław
*e-mail: joanna.czulak@pwr.edu.pl


This paper presents methods of the synthesis and applications of biomimetic catalytic systems produced from molecularly imprinted polymers (MIP). MIPs contain cavities, which are complementary to the imprinted template, thus possess high selectivity and affinity for the molecules resembling template. MIPs have various applications such as: sorption, chromatography, solid phase extraction, drugs transport and catalysis. However, this article is a review of catalytic systems containing in their active sides one of the selected metal ions: copper(II), cobalt(II), zinc(II), iron(III) or nickel(II). Presented catalytic systems are used in hydrolysis, oxidations, hydrogenations and aldol condensation reactions. This review deals with papers published till 2013.

Keywords: molecularly imprinted polymers, biomimetic catalytic systems, hydrolysis, oxidations, hydrogenations, aldol condensations


Wiadomości Chemiczne, 2014, 68, 783.
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phosphoramidate pronucleotides and THeir Intracellular activation mechanism

Katarzyna Kulik1*, Janina Baraniak1,2

1 Centrum Badań Molekularnych i Makromolekularnych Polskiej Akademii Nauk, Zakład Chemii Bioorganicznej, ul. Sienkiewicza 112, 90-262 Łódź
2 Wydział Matematyczno-Przyrodniczy, Instytut Chemii i Ochrony Środowiska, Akademia im. Jana Długosza, Al. Armii Krajowej 13/15, 42-200 Częstochowa
*e-mail: kpieta@cbmm.lodz.pl


Nucleoside analogues have great therapeutic potential for the treatment of cancer and viral diseases. Once inside the cell, they are activated by a series of intracellular phosphorylation steps to produce 5'-triphosphate derivatives, which can be incorporated to DNA or RNA and act as terminators of growing polynucleotide chains [1c]. In many cases, nucleoside analogues are poor substrates for the cellular kinases needed for their activation [5]. It is clear that intracellular introduction of nucleoside analogues as phosphorylated metabolites (so called pronucleotides) could circumvent difficulties associated with the use of non-phosphorylated nucleoside analogues and could even activate inactive compounds or could increase the activity of the nucleoside analogues. However, polarity and a ready degradation by phosphatases make the use of free nucleotide analogues impractical. Therefore, much of the recent efforts have been focused on finding suitable prodrugs of nucleoside analogue monophosphates.

Among the current diverse prodrug approaches, nucleoside phosphoramidate derivatives appear to be an interesting class of antiviral and anticancer agents [1c]. These prodrugs, as are devoid of negative charge, should be able to cross the cell membrane either by diffusion or utilizing transport protein [1c].

Conducted cell extract studies have provided evidence of a bioactivation mechanism that relies on enzyme-catalyzed P-N bond hydrolysis in phosphoramidate pronucleotides [1a,b]. It was assumed that phosphoramidate derivatives should generate nucleoside monophosphates inside the cell at rates that are influenced by both the nature of the amino group and the pH of the medium. Then nucleoside monophosphates should be phosphorylated in two different steps to the corresponding 5'-O-triphosphates (NTP) which can inhibit polymerase or be incorporated into the DNA strand being synthesized in the cell.

Over the last decade extensive studies has been carried out to establish the mechanism of action of phosphoramidates and identification of enzymes responsible for bioactivation this pronucleotides to phosphorylated nucleosides [7, 21, 24]. Investigation of metabolism pathways provided evidence that phosphoramidase activity of Hint (histidine triad nucleotide-binding proteins) play a key role in the activation of phosphoramidate pronucleotides [23-27].

Keywords: pronucleotides, phosphoramidates, phosphoramidase activity, Hint (histidine triad nucleotide binding protein), prodrug


Wiadomości Chemiczne, 2014, 68, 811.
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ALGAE AND HUMAN HEALTH

Katarzyna Godlewska, Izabela Michalak*, Katarzyna Chojnacka

Politechnika Wrocławska, Wydział Chemiczny, Instytut Technologii Nieorganicznej i Nawozów Mineralnych, ul. Smoluchowskiego 25, 50-372 Wrocław
*e-mail: izabela.michalak@pwr.wroc.pl


Marine algae are rich in a variety of biologically and pharmacologically active substances. They are considered as a resource that has been used by humans to some extent [6]. Nowadays, algal biomass is a renewable source of many valuable bioactive substances, having a wide array of applications in many industries, such as food, chemical, agricultural, pharmaceutical, cosmetic, medical. The present work focuses on the impact of algae on the human body. The potential use of algae and algal extracts in medicine and cosmetic industry is discussed. Due to the antibacterial, antiviral, antifungal, anti-inflammatory properties, algae can be used in the curing of many types of diseases [7, 8]. These properties result from the biologically active compounds present in the biomass of algae. The components of the algae that may help in the treatment tumor diseases are: polyphenols [37], polysaccharides [38], carrageenan [33-35], fucoidan [24, 30-32], fucoxanthin [25], diterpenes [27-29] or monoterpenes [36]. Substances extracted from algae with anti-inflammatory, antipyretic and analgesic include: fucosterol [48], porphyrins [52], lactones, phenols, carbohydrates [40], polysaccharides [51, 53, 54], fucoidan [46], galactan [49], fucan [45]. Fucoxanthin [64-68], fucoidan [58], triacyloglycerols [69], polyphenols [71] or phlorotannin [63] can be used as anti-obesity agents. Overreaction of the immune system to harmless environmental substances can be minimized by the use of antiallergic substances, which include mainly phlorotannins [73, 77, 78] and fatty acids [79, 80]. The components of algae, such as polysaccharides [99-101], diterpenes [91], bromophenol [90], carbohydrates [102], fucans [96, 97], galactans [98], carrageenan [94], fucoidan [92] or galactofucan [93] could be successfully utilized against various types of viruses. It has been proved that algae show dermatological and cosmetic properties: anti-inflammatory and bactericidal action (due to the presence of zinc) [8, 9, 19, 113], increase of the flexibility of the skin (peptides and vitamins) [13, 104, 105], improve blood circulation of the skin and thanks to the alginic acid they treat erythema [13, 103]. They influence on of inhibition of sebum secretion and on other problems of oily skin. Algae are used in many cosmetics to tone up the skin, lighten stretch marks [104, 111, 112]. Compresses made of algae slenderize and eliminate cellulite. A field of skin cosmetics called Thalassotherapy is a form of therapy that uses marine climate, sea water, mud, algae, sand and other substances derived from the sea as a therapeutic agents [13, 103].

Keywords: macroalgae, biologically active compounds, medicine, cosmetics


Wiadomości Chemiczne, 2014, 68, 833.
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LITHIUM BATTERIES AS MODERN ENERGY STORAGE SYSTEMS

Monika Bakierska*, Agnieszka Chojnacka

Uniwersytet Jagielloński, Wydział Chemii, Zakład Technologii Chemicznej, ul. Ingardena 3, 30-060 Kraków
*e-mail: bakierska@chemia.uj.edu.pl


Due to the need for comprehensive management of energy resources, the storage of energy becomes an increasingly important issue. From the analysis of the advantages and drawbacks of all methods of energy storage, reversible electrochemical cells seem to be the most effective. Among them, rechargeable lithium batteries are characterized by high energy density (Fig. 1), high voltage and good cyclic stability [7]. Thus, they have been a dominant technology of energy storage systems for over a decade. It is expected that market demand for Li-Ion cells in the coming years will grow at a rapid rate, as a result of their widespread use inter alia in portable electronic devices such as mobile phones, smartphones, tablet PCs and laptops (Fig. 2) [9].

This article presents the characteristics of lithium batteries. The most commonly used cathode material in Li-Ion battery is layered cobalt oxide (130 mAh/g). However, it is expensive and toxic material, thus manganese-based compounds (LiMnO2, LiMn2O4), polyanionic olivine structured materials (LiFePO4) and silicates Li2MSiO4 (M = Mn, Co, Fe) gain an increasing interest. Due to the presence of two lithium ions in the structure of silicates, these materials have a high theoretical capacity, reaching about 300 mAh/g (Tab. 2) [1, 7-9, 11, 12].

Commercially used anode material is graphite (372 mAh/g). Nevertheless, scientists are still looking for new anode materials with a higher gravimetric capacity. Researches are primarily focused on modifications of the graphite or the use of lithium alloys with other elements (Sn, Al, Si) (Tab. 3) [1, 9, 12, 14, 15].

In the Lithium-Ion cells only non-aqueous solutions are used in the character of electrolytes. As a best material, the inorganic electrolyte lithium salts (such as LiBr, LiAsF6, LiPF6, LiBF4, etc.) soluble in organic solvents are used [1, 2, 7, 8]. However, the study on alternative solutions (polymer electrolytes) is very important.

Continuous technological progress makes the research on improving the reversible electrochemical cells necessary to fulfill the expectations of users in order to improve the quality of their lives.

Keywords: Li-Ion batteries, anode materials, cathode materials, electrolytes


Wiadomości Chemiczne, 2014, 68, 858.
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SYNTHETIC EQUIVALENTS OF PHOSPHOENOLPYRUVATE - HOW TO IMITATE THE BIOSYNTHESIS OF ULOSONIC ACIDS

Marta Agnieszka Molenda

Wydział Chemii, Uniwersytet Jagielloński, ul. Ingardena 3, 30-060 Kraków, Polska
e-mail: marta.molenda@gmail.com


Ulosonic acids are key intermediated in many important biochemical pathways. One of them is DAH, which takes part in the shikimic acid pathway, as precursor in aromatic amino acids biosynthesis [1]. Another interesting compound is KDN isolated from rainbow trout egg [2], where it is responsible for the protection of the embryo in the early stages of embryonic development [3].

In the nature ulosonic acids are synthesized from phosphorylated sugar aldehydes and phosphoenolpyruvate in enzymatic aldol reaction. Mimic of enzymatic catalysis by asymmetric direct aldol reaction is one of the challenges of modern organic synthesis. Unfortunately, installation of the pyruvate unit in laboratory conditions is quite problematic.

The aim of this short review was to present synthetic equivalents of phosphoenolpyruvate, which over the years become more and more similar to the biosynthesis of ulosonic acids in living cells.

The first applied pyruvic acid unit was 2-acethylthiazole used as stoichiometric lithium enolate in aldol addition [9]. Next, the same research group used the phosphine derivative of 2-acethylthiazole in Wittig olefination of sugar aldehydes with subsequent stereoselective syn Michael addition of the benzyl oxide anion.

Another puryvate equivalent is dimethyl acetal of pyruvic aldehyde successfully used in organocatalytic [12] and metalorganocatalytic [14] direct aldol reactions.

Nowadays sterically hindered aromatic ester of pyruvic acid is probably the best puryvate unit. This ester was successfully used as aldol reaction donor in synthesis of two 3-deoxy-2-ulosonic acids - KDG and KDO [18]. Aryl pyruvate reacts with aldehydes to give aldol product with high efficiency and good diastereoselectivity in reaction catalyzed by chiral tertiary amines represented by Cinchona alkaloids. Chiral sugar aldehydes and pyruvate ester, are the building blocks that famously mimic the biological precursors of ulosonic acids.

Keywords: aldol reaction, pyruvate unit, ulosonic acids


Wiadomości Chemiczne, 2014, 68, 873.
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MULTILAYERED POLYMER FILMS OBTAINED BY MEANS OF LAYER-BY-LAYER (LBL) METHOD: EVOLUTION AND APPLICATIONS

Artur Jarema Wójcik

Wydział Chemii Uniwersytetu Jagiellońskiego, ul. R. Ingardena 3, 30-060 Kraków
e-mail: artur2.wojcik@uj.edu.pl


he production of varied materials with nanoscale precision requires both suitable components and a right method. In the past two decades, layer-by-layer (LbL) assembly has been proven to be a convenient and versatile technique for fabrication of functional films. The LbL method enables obtaining systems composed of a few or even hundreds layers of beforehand chosen substances, which are characterized by a thickness ranging from nano- to micrometers. The building blocks of LbL assembly include, but are not limited to, synthetic polymers, polymeric microgels, biomacromolecules, (nano)particles, dendritic molecules, and complexes of these species [1].

This method involves simple alternative adsorption of oppositely charged polyelectrolytes on supporting materials [2]. The LbL assembly can be driven by multiple weak interactions, including electrostatic interactions, hydrogen-bonds, halogen-bonds, coordination bonds, charge-transfer interactions, biospecific interactions (e.g., sugar-lectin interactions), cation-dipole interactions, and the combined interaction of the above forces, etc.

The multilayered composite films fabricated by means of the LbL technique have generated much interest among researchers worldwide due to the simplicity of the whole process by which they are produced and their numerous applications such as antire?ection coatings, superhydrophobic surfaces, electrochromic devices, biosensors, cell adhesion or resistance coatings, drug delivery systems, proton exchange membranes, solar-energy conversion devices, and separation membranes [3].

In this review the evolution of the LbL method and the applications of the multilayered polymer films were discussed.

Keywords: LbL, polymer films, polyelectrolytes


Wiadomości Chemiczne, 2014, 68, 897.
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THE PURSUIT OF SOOT

Anna Kopacz

Uniwersytet Jagielloński, Wydział Chemii, Zakład Chemii Nieorganicznej, Grupa Chemii Powierzchni i materiałów, ul. Ingardena 3, 30-060 Kraków
e-mail: anna.kopacz@uj.edu.pl


Soot is produced simultaneously by the incomplete combustion of fossil fuels. Investigations of soot elemination methods are currently focused on light fuel oil boilers. The overview of various transition metal properties points at iron as the most promising cation. The technology of existing oil burners excludes modifications necessary to install additional catalytic conversters. The most feasible way to eliminate soot is to introduce the catalyst in the form of fuel additive. Iron iron oxides and/or hydroxides are suggested as base for production of fuel-borne-catalyst.

Keywords: catalysis, iron oxide, catalyst, soot, combustion


Wiadomości Chemiczne, 2014, 68, 919.
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SYNTHESIS AND APPLICATION OF NEW OLEFIN METATHESIS CATALYSTS

Agnieszka Hryniewicka

Uniwersytet w Białymstoku, Instytut Chemii, Zakład Chemii Produktów Naturalnych, ul. Hurtowa 1, 15-399 Białystok
e-mail: aga_h@uwb.edu.pl


Olefin metathesis has emerged as a powerful tool for the formation of carbon-carbon double bonds. The success of this methodology has spurred the intense investigation of new catalysts showing a better application profile. The syntheses and the application profiles of the seven new ruthenium metathesis catalysts have been described. Five of them were modified in benzylidene part with 6-hydroxychromane- and 2H-3,4-chromenemethylidene moiety. In chromanol -αtocopherol model compound, some specific stereoelectronic effects have been observed. Introduction of this ligand to the catalyst may provide new advantageous properties. The other new catalysts contained modified N-heterocyclic carbene ligand (NHC), in which N,N'-mesityl substituents of NHC system were linked with diethylene glycol chain as a "clamping ring". This ring would contribute to a steric shield of the NHC and ruthenium coordination center. Probably it may inforce a proper orientation of substituents in metallacyclobutane (all-cis), leading to Z-olefin formation. The obtained catalysts were investigated in model reactions: ring closing metathesis, cross metathesis and enyne metathesis. The experiments proved they efficiency. In many reactions the catalysts showed activity comparable or superior to that of commercially available Grubbs and Hoveyda 2nd generation complexes. Stereochemistry Z/E of the cross-metathesis products obtained using new and known complexes were similar as well. The catalysts were applied in the synthesis of a new type of α-tocopherol glycoconjugates. An efficient method of the synthesis Hoveyda 2nd type complexes starting from ruthenium trichloride was developed. It is possible to circumvent using special laboratory equipment and expensive reagents. Hoveyda type complexes can be achieved with very good yield in gram scale.

Keywords: olefin metathesis, ruthenium catalysts, chromane derivatives, imidazolinium salts, glycoconjugates


Wiadomości Chemiczne, 2014, 68, 961.
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SYNTHESIS AND BIOLOGICAL ACTIVITY OF SELECTED MANNICH BASES

Wanda Paulina Nawrocka, Anna Nowicka

Katedra i Zakład Technologii Leków, Uniwersytet Medyczny im Piastów Śląskich we Wrocławiu, ul. Borowska 211a, 50-556 Wrocław
e-mail: anna.nowicka@umed.wroc.pl


The Mannich reaction is important for the synthesis and modification of biologically active compounds. Mannich bases - substituted products containing different heterocyclic system in their structures seem to be suitable candidates for further chemical modifications and might be of interest as pharmacologically active compounds.

The main goal of this article is to present synthesis and biological activity of selected Mannich bases. Based on a review of the chemical literature, Mannich bases showed a multipharmacological effects. The Mannich bases, containing various heterocyclic systems were identified as potent anticancer agents. Presented compounds exhibit cytotoxic, antiproliferate in vitro, anticonvulsant, antioxidative, antiinflaminatory and analgesic activity. Some of them can be used in a treatment of diabetes and hypertension.

Keywords: Mannich bases, biological activity, synthesis


Wiadomości Chemiczne, 2014, 68, 981.
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ENANTIOSELECTIVE ENZYMATIC DESYMMETRIZATION CATALYZED BY OXIDOREDUCTASES. REDUCTION REACTIONS. PART II

Renata Kołodziejska*1, Aleksandra Karczmarska-Wódzka*1, Agnieszka Tafelska-Kaczmarek2, Renata Studzińska3, Marcin Wróblewski1, Beata Augustyńska1

1 Katedra i Zakład Biochemii, Collegium Medicum Uniwersytet Mikołaja Kopernika, ul. Karłowicza 24, 85-092 Bydgoszcz
2 Katedra Chemii Organicznej, Uniwersytet Mikołaja Kopernika, ul. Gagarina 7, 87-100 Toruń
3 Katedra i Zakład Chemii Organicznej, Collegium Medicum Uniwersytet Mikołaja Kopernika, ul. dr. A. Jurasza 2, 85-089 Bydgoszcz
*e-mail: Renatakol@poczta.fm, *e-mail: akar@cm.umk.pl


Biotransformation reactions of many organic compounds under the influence of enzymes take place with the high selectivity, rarely achieved by other methods. Ketoesters represent an extensive group of selectively bioreduced compounds. Chiral hydroxyesters and, subsequently, hydroxyacids are valuable intermediates in the syntheses of various biologically active compounds. Acyclic α- and β-ketoesters are transformed to the corresponding (R)- and (S)-hydroxyesters by using a specific dehydrogenases. The whole-cells enzymes, e.g. baker's yeast, may exhibit a different catalytic activity depending on the substrate structure. Baker's yeast enzymes selectively reduce the cyclic β-ketoesters providing mainly anti diastereomers due to the lack of rotation around the single α,β carbon-carbon bond. The enzymatic reduction of the esters, cyclopentanone, and cyclohexanone derivatives gave the optically active anti-alcohol enantiomers. The reductive EED of prochiral α-ketoesters, as well as β-ketoesters is an interesting transformation in organic chemistry due to the importance of the resulting chiral α-hydroxy acids and their derivatives used as building blocks. Baker's yeast-catalyzed reduction of alkyl esters derived from pyruvate and benzoylformate allows the preparation of the (R)-alcohols.

Polyketones can also be subjected to the reductive EED to give different compounds bearing the quaternary stereogenic centers which are broadly applied in asymmetric synthesis. In asymmetric synthesis, similarly to carbon-oxygen double bonds, carbon-carbon double bonds of prochiral alkanes can be reduced to obtain the optically active saturated compounds. The reduction of alkenes is catalyzed by both, the whole cells (microorganisms, plant cells) as well as isolated enzymes belonging to the oxydoreductases, so-called ene-reductases. The whole-cell catalysts are suitable, most frequently, for the preparative scale syntheses, but they are less chemoselective in comparison to the isolated reductases. In the case of polyfunctionalized alkenes, microorganisms can cause the additional side reaction reducing the desired product yield.

Keywords: asymmetric reduction, biocatalysis, enzymes


Wiadomości Chemiczne, 2014, 68, 1009.
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TWO DECADES OF CHEMO-ENZYMATIC BAEYER-VILLIGER REACTION

Agnieszka Drożdż, Rafał Bielas, Anna Chrobok*

Politechnika Śląska, Wydział Chemiczny, Katedra Technologii Chemicznej Organicznej i Petrochemii, ul. Krzywoustego 4, 44-100 Gliwice
*e-mail: Anna.Chrobok@polsl.pl


The Baeyer-Villiger oxidation of ketones to lactones or esters is a reaction of significant interest in organic chemistry owing to very wide range of possible applications, e.g. in the synthesis of antibiotics, steroids, pheromones and monomers for polymerisation. The organic percarboxylic acids typically used as oxidants in these reactions are fairly expensive, often poorly stable and hazardous, and this consequently limits their commercial application. Therefore, the chemo-enzymatic approach appears to be a very attractive alternative. The paper presents literature reports concerning the application the use of lipase B from Candida antarctica in the chemo-enzymatic Baeyer-Villiger oxidation. It involves oxidation of long- or medium-chain carboxylic acids with H2O2 or urea hydrogen peroxide to generate in situ peracid which is later used to oxidise ketones to lactones.

Keywords: chemo-enzymatic Baeyer-Villiger reaction, lactones, cyclic ketones oxidation, lipase B Candida antarctica


Wiadomości Chemiczne, 2014, 68, 1031.
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MICROBIAL ALCOHOL DEHYDROGENASES - PROPERTIES AND THEIR APPLICATION

Ewa Szczepańska, Filip Boratyński* Uniwersytet Przyrodniczy we Wrocławiu, Katedra Chemii, ul. C. K. Norwida 25/27, 50-375 Wrocław
*e-mail: filip.boratynski@up.wroc.pl


Biotransformations involve mainly microorganisms or individual enzymes applied to catalyze chemical reactions [1]. This field of science is particularly important, because it allows to obtain optically active compounds, which are valuable raw materials for pharmaceutical (Fig. 3, Fig. 6, Fig. 20, Fig. 21), wood and paper (Fig. 18), food (Fig. 4), textile (Fig. 12), cosmetic (Fig. 14) industries and environmental protection (Fig. 19).

Oxidoreductases, in particular alcohol dehydrogenases (E.C.1.1.1.1, ADH) are valuable biocatalysts enabling to obtain enantiomerically pure products. These enzymes, commonly found in nature, catalyze both oxidation and reduction reactions [3].

Described dehydrogenases descend from mesophilic, psychrophilic and thermophilic microorganisms. The increasing application of thermophiles is due to their exceptional resistance against heat and organic solvents. The article describes and explains how microbial ADH's interact with NAD+/NADH or NADP+/NADPH and present those enzymes which catalyze reactions with both forms of cofactors. The alcohol dehydrogenases from yeast are particularly commonly used [9-14]. Bacterial enzymes, among them ADH isolated from Thermoanaerobacter brockii [47-51], are widely distributed too. In addition, the literature describes a number of (R)-specific ADH's from Lactobacillus kefir [40-42], L. brevis [45, 46], Leisofonia sp. [20] Pseudomonas fluorescens [23] and (S)-specific ADH's from Rhodococcus erythropolis [15, 16], Thermus sp. [30], Sulfolobus solfataricus [23, 28] and many others.

Keywords: alcohol dehydrogenase, biotransformations, bacteria


Wiadomości Chemiczne, 2014, 68, 1049.
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CHEMICAL COMPOSITION AND BIOLOGICAL ACTIVITY OF MEDICAL LAVENDER

Michalina Adaszyńska-Skwirzyńska*, Maria Swarcewicz

Zakład Syntezy Organicznej i Technologii Leków. Wydział Technologii i Inżynierii Chemicznej. Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Al. Piastów 42, 71-065 Szczecin
*e-mail: madaszynska@zut.edu.pl


Lavender Lavandula angustifolia Miller (formerly used synonym of L. officinalis Chaix or L. vera), commonly known as medical lavender is a species of greatest industrial importance. Lavender cultivated to be the most frequently due of the essential oil and the unique biological activity [1-4]. It is clear from the literature on the subject that lavender is characterized by its antimicrobial, antifungal, antioxidant, immunostimulating, and spasmolytic activity [5-18]. It is also claimed that it can be effective in preventing many illnesses. It is proved that lavender essential oil can be an effective drug in the treatment of many neurological disorders [13-18]. The research conducted on animals and humans exhibit activity this plant such as anxiolytic, sedative, sleep-inducing, analgesic, antitumor, anticonvulsant, and mood improving [13-26].

This paper presents an overview of the literature from recent years on the lavender [1-93]. The general characteristics of the plant and the main classes of biologically active substances are discussed. Drew attention to the need for standardization of plant and variety, identification of plant material for use in the following industries: pharmaceutical, chemical, cosmetic and food. It was found that there are few studies comparing the activity of different varieties of lavender. There is also little information about the chemical composition of different parts of the plant. There are current studies conducted towards natural synergies. This plant collects various types of biologically active substances that have therapeutic potential, but the lack of relevant information concerning dosage formulations lavender.

Medical lavender (L. angustifolia Miller) has a great potential for future applications.

Keywords: lavender (Lavandula angustifolia), chemical composition of lavender, biologically active substances.


Wiadomości Chemiczne, 2014, 68, 1073.
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MAX RUDOLF LEMBERG (1896-1975) - AN AUSTRALIAN BIOCHEMIST OF WROCŁAW ORIGIN

Jacek Wojaczyński

Wydział Chemii Uniwersytetu Wrocławskiego, ul. F. Joliot-Curie 14, 50 383 Wrocław,
e-mail: jacek.wojaczynski@chem.uni.wroc.pl


The article is devoted to Max Rudolf Lemberg (1896-1975), known primarily as an author of pioneering works on bile pigments and porphyrin degradation (in particular, coupled oxidation), and to his connections with Wrocław. This Australian biochemist of German origin was born in that city to an assimilated Jewish family. He was educated by a private teacher, and in 1905 he entered the famous liberal Johannes Gymnasium in Breslau (its building now houses Economics and Administration Schools). After leaving school in 1914, shortly before the war broke out, Lemberg began studies on natural sciences at the University of Breslau. He volunteered for an army, but was not accepted until 1917. Wounded in the Somme offensive in 1918, he resumed his studies to finish with a doctorate on the chemistry of uric acid derivatives (1921). He then became a private assistant to his Ph.D. supervisor, Professor Heinrich Biltz. However, a few years later, Biltz advised him to look for a job in the industry, and Lemberg moved to Meinheim to work for a pharmaceutical company. He often visited his native city where his parents and brother were living; in Breslau he also married Hanna Clausen in 1924. A grant from Notgemeinschaft der Deutschen Wissenschaft and job offer from Karl Freudenberg of University of Heidelberg allowed Lemberg to come back to the scientific work, in which he decided to focus on biochemical studies. From these days dates his interest in bile pigments which led him to the habilitation in 1930. He then continued his work on linear tetrapyrroles during Rockefeller Foundation Fellowship in Cambridge. Shortly after his return to Heidelberg, Nazis came to power in Germany and proclaimed the Beamtengesetz act which stated that all people of Jewish origin as well as members and supporters of opposition parties should be fined from the civil service. This ended his academic career of Lemberg in Germany. Rudolf moved to Cambridge with Hanna, however, since not all refugees could stay in the Great Britain, in 1935 he accepted a proposal from the Royal North Shore Hospital in Sydney to work as a research biochemist. The Lembergs immigrated to Australia to begin the new chapter in their life; a few years later Walter, Rudolph's brother, joined them with his family. The first years were particularly hard since the progress in the scientific work was hampered by the lack of modern laboratory equipment and experienced coworkers. In 1946, first of Lemberg's books, Hematin Compounds and Bile Pigments, co-authored by John Legge, was issued. In the following years, Rudolf broadened his interests to cytochrome c oxidase and heme A, one of the enzyme prosthetic groups. His investigations in the field were summarized in the second monograph written with Jack Barrett ("The Cytochromes", 1973). His scientific interests were not limited to chemistry: he devoted several papers and lectures to the problem of life origins and to the connections between religion and science. Rudolf Lemberg was one of the founders of Australian Academy of Sciences and Australian Biochemical Society. He died in Sydney in 1975.

Keywords: Austalian chemists, German chemists, scientists born in Wrocław (Breslau), investigators of heme degradation process, experts on bile pigments chemistry.


Wiadomości Chemiczne, 2014, 68, 1095.
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60 LAT CHEMII NA UNIWERSYTECIE WROCŁAWSKIM

Kazimiera Lukjan

Wydział Chemii Uniwersytetu Wrocławskiego, ul. F. Joliot-Curie 14, 50 383 Wrocław,


Wiadomości Chemiczne, 2014, 68, 1113.
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