Wiadomości Chemiczne

Wiadomości Chemiczne, 2013, Vol.67

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  1. Carbon Dioxide in Organic Synthesis
    Bogdan Burczyk

  2. Dihydroxy-1,1'-Binaphthyl (Binol) and its Derivatives: Selected Synthesis Methods and Applications. Part II
    Dorota Krasowska

  3. The Methods of Synthesis and Physicochemical Properties Of 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-Hexaazaisowurtzitane (HNIW)
    Jacek Borkowski, Magdalena Czerwińska

  4. Chemical Modificaton of Nanodiamond Powders Produced by Detonation Method
    Kinga Adach, Janusz Skolimowski, Katarzyna Mitura

  5. Influence of Mobile Phase Modifier on Separation Selectivity in Reversed Phase High Performance Liquid Chromatography
    Beata Misiołek, Anna Klimek-Turek, Tadeusz H. Dzido

  6. Profesor Bogdan Baranowski - stopnie życia
    Lidia Dębowska

  7. Synthesis of Selected, New 2-Amino-1h-Benzimidazole Derivatives and their Mechanism of Biological Activity
    Anna Nowicka, Wanda Paulina Nawrocka

  8. Synthesis, Structures and Biological Activity of Imidazo[4,5-b]Pyridine Derivatives. Part 2
    Hanna Liszkiewicz, Anna Nowicka, Wanda Paulina Nawrocka

  9. Synthesis and Biological Activity of Pyrrolo[3,4-c]Pyridine Derivatives
    Anna Wójcicka

  10. Nanopores: Structure, Properties, Models, Applications
    Anna Stachiewicz, Andrzej Molski

  11. Secondary Plant Metabolities as Antimicrobial Agents
    Michalina Adaszyńska, Maria Swarcewicz

  12. Percutaneous Penetration of Active Cosmetics Ingredients
    Magdalena Malinowska, Elżbieta Sikora, Jan Ogonowski

  13. Active Ingredients of Paint Remover
    Grzegorz Kurowski, Otmar Vogt, Jan Ogonowski

  14. The Experiments of Michał Jan Borch (1753-1811) Concerning Chemiluminescence
    Ignacy Z. Siemion, Alicja Szastyńska-Siemion

  15. Trans-1,2-Diaminocyclohexane - Unprecedented Outsider's Career
    Małgorzata Petryk, Marcin Kwit

  16. Cinchona Alkaloids - Small Hardworkers
    Karol Kacprzak, Paweł Czarnecki

  17. Tartaric Acid and its Derivatives in Current Organic Chemistry
    Jakub Grajewski

  18. Zinc-catalyzed Asymmetric Hydrosilylation of Ketones and Imines
    Jadwiga Gajewy

  19. Beauty of Chemical Molecules: Self Organized Covalent Molecular Cages
    Paweł Skowronek

  20. Asymmetric Aziridine Ring Opening Reactions
    Natalia Prusinowska

  21. Okruchy XXVIII. Rozmyślania o czasie minionym
    Ignacy Z. Siemion

  22. Methods of Investigation Energetical Heterogeneity on the Surface of Catalysts and Adsorbents
    Piotr Woszczyński

  23. Magnetic Resonance Imaging Contrast Agents Exemplified by Iron Complexes
    Nikodem Kuźnik, Marzena Wyskocka

  24. Synthesis Of Selected Drugs 2-Amino-1H-Benzimidazole Derivatives
    Anna Nowicka, Wanda Paulina Nawrocka

  25. Selected Methods of the Synthesis of 2-Amino-1H-Benzimidazole
    Wanda Paulina Nawrocka, Anna Nowicka

  26. A Short History of Some Formulas
    Wojciech Kroszczyński

  27. Enantioselectve Enzymatic Desymmetrization Catalyzed in the Presence of Lipase. Part I. Prochiral Compounds
    Renata Kołodziejska, Aleksandra Karczmarska-Wódzka, Agnieszka Tafelska-Kaczmarek, Renata Studzińska, Marcin Dramiński

  28. Okruchy XXIX. O Moich Książkach
    Ignacy Z. Siemion

  29. Wspomnienia o Profesorze Hubercie Kołodzieju
    Kazimierz Orzechowski

  30. Proline as a Common Amino Acid and an Exceptional Catalyst. Part I. Proline Biosynthesis. Intramolecular Aldol Reaction
    Marcin Wróblewski, Renata Kołodziejska, Renata Studzińska, Aleksandra Karczmarska-Wódzka, Marcin Dramiński

  31. Enantioselectve Enzymatic Desymmetrization Catalyzed in the Presence of Lipase. Part II. Optymalization of Reaction Conditions. Meso Compounds
    Aleksandra Karczmarska-Wódzka, Renata Kołodziejska, Agnieszka Tafelska-Kaczmarek, Tomasz Przybyła, Marcin Dramiński

  32. Mitsunobu Reaction - Mechanism and Application
    na D. Kitkowska, Żaneta A. Tabaczyńska, Marcin Dramiński

  33. Bioactive N-Acylphosphoramidate Nucleoside Derivatives
    Katarzyna Kulik

  34. Two-Dimensional Separation with Chromatography and Electrophoresis Techniques with Special Focus on their Combination into Single Process
    Eryk Łopaciuk, Tadeusz H. Dzido

  35. Scherrer Formula - the Century of Erroneous Practices
    Paweł E. Tomaszewski

  36. Synthesis of γ-Lactones with Aromatic Substituents
    Andrzej Skrobiszewski, Witold Gładkowski

  37. Okruchy XXX. O Tajemnicy Zawartej w "Pamiętniku Znalezionym w Saragossie" Jana Potockiego
    Ignacy Z. Siemion

  38. Currently Available Surfactants and their Micellar Structures Formed in Aqueous Solutions
    Anna Jakubowska

  39. Modified Oligodeoxyribonucleotides Containing Nitrogen at a Bridging Position of an Internucleotide Bond
    Ewa Radzikowska

  40. Proline as a Common Amino Acid and an Exceptional Catalyst. Part II. Intermolecular Aldol Reaction
    Renata Kołodziejska, Marcin Wróblewski, Aleksandra Karczmarska-Wódzka, Renata Studzińska, Marcin Dramiński

  41. Biological Activity of Thiazolo[4,5-d]Pyrimidine Derivatives
    Lilianna Becan

  42. Synthesis of Pyrazolo[4,3-c]Heterocyclic Derivatives
    Anna Wójcicka

  43. The Mechanism of Resistance to Platinum Drugs and Strategies to Overcome this Phenomenon
    Wanda Weiss-Gradzińska, Wojciech Krzempek, Lilianna Trynda-Lemiesz

  44. Influence of Brewing Conditions on Antioxidant Content in Different Kinds of Tea Infusions
    Kamil Kurleto, Grzegorz Kurowski, Barbara Laskowska, Magdalena Malinowska, Elżbieta Sikora, Otmar Vogt

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CARBON DIOXIDE IN ORGANIC SYNTHESIS

Bogdan Burczyk

Wydział Chemiczny Politechniki Wrocławskiej, Wybrzeże S. Wyspiańskiego 27, 50-370 Wrocław
e-mai: bogdan.burczyk@pwr.wroc.pl


Carbon dioxide is an abundant, cheap, almost nontoxic, thermodynamically stable, inert electrophile. Exploitation of CO2 as a chemical feedstock, although will almost certainly not reduce its atmospheric concentration significantly, aims to generate high-value products and more-efficient processes. In recent years efficient transition-metal complexes have been used to perform homogeneously catalyzed transformations of CO2. This paper presents an overview of available catalytic routes for the synthesis of carboxylic acids, lactones, urea and carbamates, linear and cyclic carbonates as well as polycarbonates. Reduction processes of CO2 are shortly mentioned as well.

Carboxylic acids have been synthesized via: (i) carboxylation of organolithium, organomagnesium (Scheme 2 [35]), organoboron (Scheme 3 [40-42]), organozinc (Scheme 4 [43, 44]) and organotin (Scheme 5 [45, 46]) compounds; (ii) oxidative cycloaddition of CO2 to olefins and alkynes (Scheme 6-10 [47-50, 57]) catalyzed by Ni(0)-complexes; (iii) transition-metal catalyzed reductive hydrocarboxylation of unsaturated compounds (Scheme 11, 12 [64-67]); (iv) carboxylation of C-H bond (Scheme 13 [69-71]). Telomerization of dienes, for instance 1,3-butadiene, and CO2 in the presence of Ni(II) and Pd(II) complexes leads to lactones and esters of carboxylic acids (Scheme 14, 15 [73-79]). Nucleophilic ammonia, primary and secondary amines react with CO2 to give, respectively, urea and carbamic acid esters - carbamates and isocyanates (Scheme 16-18 [94, 95]), thus eliminating the use of phosgene in their synthesis. CO2 reacts with alcohols, diols and epoxides in the presence of transition-metal complexes (Fig. 2) and the reaction products are: linear carbonates (Scheme 20, 21 [110-118]), cyclic carbonates (Scheme 22-24 [153-170]) and polycarbonates (Scheme 25, 26, Fig. 3, Tab. 1 [179-186]). Finally, hydrogenation of CO2, leading to the formation of CO, HCOOH, CH3OH, CH4, C2H6 and C2H4 (Scheme 27), as well as electrochemical and photochemical reductions in the presence of homogeneous and heterogeneous catalysts have been shortly reviewed.

Keywords: carbon dioxide fixation, renewable resources, organic synthesis, catalysis, transition-metal complexes


Wiadomości Chemiczne, 2013, 667, 1.
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2,2'-DIHYDROXY-1,1'-BINAPHTHYL (BINOL) AND ITS DERIVATIVES: SELECTED SYNTHESIS METHODS AND APPLICATIONS. PART II

Dorota Krasowska

Centrum Badań Molekularnych i Makromolekularnych w Łodzi, Polska Akademia Nauk ul. Sienkiewicza 112, 90-363 Łódź, Poland
e-mail: dkras@cbmm.lodz.pl


An invention of new catalytic strategies for stereoselective synthesis is of current interest to many laboratories worldwide. Over the past few decades a remarkable progress in the field of stereocontrolled synthesis has been achieved with chiral 1,1'-binaphthyl compounds. Optically active 1,1'-binaphthyl-2,2'-diol (BINOL) and its derivatives due to their axial dissymmetry and molecular flexibility have been widely utilized as chiral ligands and auxiliaries in stoichiometric or catalytic asymmetric reactions, such as metal-catalysed transformations and enantioselective organocatalysis. BINOL and its functionalized analogues have demonstrated remarkable chiral discrimination properties. Extensive studies on molecular recognition provided the successful results in the application of BINOL as a host for an optical resolution of racemic guests and as a chiral NMR shift reagent for the determination of chiral compounds. It has been found that the axial chirality of binaphthyl units in host molecules is crucial contribution to their stereoselctive complexation with chiral guests.

Keywords: BINOL, atropoisomers, oxidative coupling, optical resolution, enantioselective synthesis, chiral ligands


Wiadomości Chemiczne, 2013, 67, 55.
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THE METHODS OF SYNTHESIS AND PHYSICOCHEMICAL PROPERTIES OF 2,4,6,8,10,12-HEXANITRO-2,4,6,8,10,12-HEXAAZAISOWURTZITANE (HNIW)

Jacek Borkowski, Magdalena Czerwińska

Wojskowy Instytut Techniczny Uzbrojenia, Zakład Badań Środków Bojowych, ul. Prym. St. Wyszyńskiego 7, 05-220 Zielonka
e-mail: czugalam@witu.mil.pl


Explosives have a very rich history of its creation. This history dates back to the ninth century, when the Chinese invented a black powder. In the end of the twentieth century, the first nitroamine polycyclic cage structure was obtained. The representative of this group is 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaizowurtzitane (HNIW, Cl-20). HNIW has recently been the subject of an interest as one of the strongest explosive material.

As nitroamine, HNIW is compared to the other energetic materials: RDX i HMX [1, 2]. Researchers [5, 6] showed, that it is possible to replace a variety of typical explosives by HNIW and thanks to that obtain compositions with higher densities, heat of explosion and higher velocity of detonation.

In the published papers [7-13, 16] there were presented six polymorphs of HNIW: αβγδε with specific stabilities and structural characteristics.

Unfortunately, there is no a direct method of obtaining HNIW. There are at least four steps needed to obtain HNIW. The first step is the synthesis of HBIW [20-22]. The next one is debenzylation reaction of HBIW [20-29] in order to remove the benzyl groups. The third step is removal of the two other benzyl groups and replace them by nitroso, formyl or acetyl groups [20, 24, 30, 32]. In the final step there is a nitration of HNIW precursors [31-37].

The HNIW seems to be a promising explosive and it can replace other currently used energetic materials. However, using HNIW is limited due to the complicated and expensive technology of its production. Therefore, research groups carried out new syntheses of HNIW to eliminated these problem.

In this article, review of the literature on the physicochemical properties and synthetic methods for HNIW were presented. The basic physical and explosive parameters of HNIW were summarized. The spatial structure was presented and polymorphs of HNIW were characterized. The methods for obtaining HNIW and intermediate products needed for its preparation were described. The methods of preparation of different HNIW polymorphs were also given.

Keywords: 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaizowurtzitane, Cl-20, HNIW, synthesis, chemical and explosive properties.


Wiadomości Chemiczne, 2013, 67, 93.
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CHEMICAL MODIFICATON OF NANODIAMOND POWDERS PRODUCED BY DETONATION METHOD

Kinga Adach1, Janusz Skolimowski2, Katarzyna Mitura3

1 Instytut Inżynierii Materiałowej, Zakład Inżynierii Biomedycznej, Wydział Mechaniczny, Politechnika Łódzka, ul. Stefanowskiego 1/15, 90-924 Łódź, e-mail: kingasub@wp.pl
2 Katedra Chemii Organicznej, Wydział Chemii Uniwersytetu Łódzkiego, ul. Tamka 12, 91-403 Łódź, e-mail: jskolim@uni.lodz.pl
3Instytut Technologii i Edukacji, Wydział Mechaniczny, Politechnika Koszalińska, ul. Śniadeckich 2, 75-453 Koszalin' e-mail: mitura.katarzyna@gmail.com


Nanodiamonds are diamond particles measured in nanometers. The ideal nanodiamond molecule should have surface ability to bind with many organic groups. They are also susceptible to chemical modifications. Nanodiamonds due to their biocompatibility and low toxicity, can be used for biological materials or in medicine. They can also be used as drug carriers and as covalent and electrostatic binding to the active biomolecules.

This review describes the chemical modification of nanodiamond powders. This research work aimed and gain new knowledge, understanding and interpretation of the phenomena occure during the chemical functionalization of nanodiamond powders. An observation and an analysis of the mechanisms of chemical bonds formation or physical interactions will broaden the knowledge in this field. An examination of the impact of organic groups on the nanodiamond surface and onto its physical and chemical properties contribute to the selection of the best method of modification. An implementation research allows to broaden the knowledge in the field of chemical surface modification of nanodiamonds powders.

Keywords: nanomaterials, diamond nanopowders, purification, chemical modification, surface functionalization


Wiadomości Chemiczne, 2013, 67, 111.
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INFLUENCE OF MOBILE PHASE MODIFIER ON SEPARATION SELECTIVITY IN REVERSED PHASE HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Beata Misiołek*, Anna Klimek-Turek, Tadeusz H. Dzido

Zakład Chemii Fizycznej, Katedra Chemii, Uniwersytet Medyczny w Lublinie, ul. Chodźki 4A, 20-093 Lublin
e-mail*: beata.misiolek@umlub.pl


High performance liquid chromatography (HPLC) is an instrumental analytical technique, which is widely used for a separation and determination of a mixture of components in many samples (e.g. of biomedical, pharmaceutical, food, and environmental origin). Despite several decades of the development of this technique, some aspects of the chromatographic process are still open to questions. This is particularly related to mechanisms of retention and selectivity of a separation. Improvement of the separation selectivity can be achieved by a change of the stationary phase type and qualitative and/or quantitative composition of the mobile phase. The replacement of the stationary phase does not ensure a smooth change of selectivity and retention, however, it generates additional costs of analysis. Therefore, the optimal conditions of chromatographic separation can be easily obtained by the change of a composition of the mobile phase, i.e. the type and/or concentration of its modifier (organic solvent).

This paper presents an overview of approaches to explanation and interpretation of an influence of mobile phase composition on the retention and separation selectivity in liquid chromatography systems with particular emphasis on modifier type of eluent in the reversed phase high performance liquid chromatography (RP HPLC).

Keywords: retention of solutes, separation selectivity, the effect of modifier on selectivity, reversed phase high performance liquid chromatography, HPLC, RP HPLC


Wiadomości Chemiczne, 2013, 67, 133.
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PROFESOR BOGDAN BARANOWSKI - STOPNIE ŻYCIA

Lidia Dębowska

Sekcja Historii Chemii Polskiego Towarzystwa Chemicznego, Oddział w Warszawie
e-mail: debowska.ld@gmail.com



Wiadomości Chemiczne, 2013, 67, 161.
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SYNTHESIS OF SELECTED, NEW 2-AMINO-1H-BENZIMIDAZOLE DERIVATIVES AND THEIR MECHANISM OF BIOLOGICAL ACTIVITY

Anna Nowicka*, Wanda Paulina Nawrocka

Katedra i Zakład Technologii Leków, Uniwersytet Medyczny im Piastów Śląskich we Wrocławiu, pl. Nankiera 1, 50-140 Wrocław
*e-mail: anna.nowicka@umed.wroc.pl


Many 2-amino-1H-benzimidazole drugs such as antihistaminic mizolastine and norastemizole or antiparasitic mebendazole, albendazole and thiabendazole have been used in clinic [1,2]. Benomyl and its metabolite Carbendazim are both antifungal and anticancer drugs [4].

Recently, a lot of literature has revealed that 2-amino-1H-benzimidazole derivatives could effectively inhibit the growth of various microorganisms, what suggests that 2-aminobenzimidazole compounds should have large potential as a new type of antibacterial [15] and antifungal [18] agents.

A number of 2-aminobenzimidazoles have exhibited antiproliferative in vitro properties [11]. Some new compounds, containing in theirs structures 2-aminobenzimidazole, show interesting and diverse cytotoxic mechanism of action, e.g. induce apoptosis of cancer cells [13]. Some of 2-aminobenzimidazole analogues are histamine and serotonin receptors antagonists [32]. 2-Aminobenzimidazoles derivatives have been frequently found to display a variety of biological activities like anti-inflammatory, antioxidant and anticoagulant [32] properties.

Keywords: 2-amino-1H-benzimidazole derivatives, synthesis, biological activity


Wiadomości Chemiczne, 2013, 67, 203.
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SYNTHESIS, STRUCTURES AND BIOLOGICAL ACTIVITY OF IMIDAZO[4,5-b]PYRIDINE DERIVATIVES. PART 2

Hanna Liszkiewicz, Anna Nowicka*, Wanda Paulina Nawrocka

Katedra i Zakład Technologii Leków, Uniwersytet Medyczny im Piastów Śląskich we Wrocławiu, pl. Nankiera 1, 50-140 Wrocław
*e-mail: anna.wojcicka@umed.wroc.pl


The main goal of this article is to present selected syntheses, structures and a various biological activity of imidazo[4,5-b]pyridine derivatives. During the past 20 years the biological activity of imidazo[4,5-b]pyridine have been intensively studied.

Based on the review of the chemical literature, it was shown that derivatives of imidazole[4,5-b]pyridine showed a multipharmacological effects such as antibacterial effect [20-22] and antituberculotic activity [25-33], nonsteroidal antiinflammatory activity [35-43] and analgesic [44, 45] effect. Among compounds of this class antagonists of angiotensin II receptors that exhibit hypotensive activity are also known [9-11].

Compounds containing imidazo[4,5-b]pyridine moiety can be synthesized from different substrates. The most useful starting compounds for the synthesis of imidazo[4,5-b]pyridine are derivatives of 2,3-diaminopyridine [1-3].

Keywords: imidazo[4,5-b]pyridine derivatives, biological activity, synthesis, structures


Wiadomości Chemiczne, 2013, 67, 227.
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SYNTHESIS AND BIOLOGICAL ACTIVITY OF PYRROLO[3,4-c]PYRIDINE DERIVATIVES

Anna Wójcicka

Katedra i Zakład Technologii Leków, Uniwersytet Medyczny im. Piastów Śląskich we Wrocławiu, pl. Nankiera 1, 50-140 Wrocław
email: anna.wojcicka@umed.wroc.pl


Pyrrolo[3,4-c]pyridine is one of the six structural isomers of the bicyclic ring system containing pyrrole moiety condensed with a pyridine nucleus. This review presents most of the literature data about synthetic pyrrolo[3,4-c]pyridine derivatives and their biological activity.

S. Gabriel and J. Colman [4] discovered this isomer for the first time and named it "merimine" [Fig. 3]. The main goal of this study is the presentation of various methods for the preparation of pyrrolo[3,4-c]pyridine derivatives. Compounds containing the pyrrolo[3,4-c]pyridine scaffold can be synthesized from different substrates, but the syntheses may be classified into two main categories: annulation of pyrrole ring onto pyridine derivatives or annulation of pyridine ring onto pyrrole derivatives.

Biological investigations have shown that pyrrolo[3,4-c]pyridine derivatives have a wide spectrum of actions. Most of them have been studied as analgesic and sedative agents [35-40]. Antitumor [19, 42, 45], antiviral [27], antituberculostatic [43] activities have been found. Pyrrolo[3,4-c]pyridine derivatives can also be used in the treatment of nervous [20, 41] and immune [19, 42] system diseases.

Keywords: pyrrolo[3,4-c]pyridine derivatives, synthesis, biological activity


Wiadomości Chemiczne, 2013, 67, 251.
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NANOPORES: STRUCTURE, PROPERTIES, MODELS, APPLICATIONS

Anna Stachiewicz, Andrzej Molski

Zakład Chemii Fizycznej, Wydział Chemii, Uniwersytet im. Adama Mickiewicza, ul. Grunwaldzka 6, 61-606 Poznań
e-mail: anna.st@amu.edu.pl, amolski@amu.edu.pl


Nanopores are small (1-100 nm diameter) holes/channels formed in biological membranes (Fig. 1) or fabricated in synthetic materials (Fig. 2). Permeation of ions and small molecules through nanopores is common in biological systems. The first experiments where nanopores were used as single-molecule sensors were performed in the 90s [1, 2]. The detection principle is based on a monitoring of an ionic current passing through a nanopore as an electric field is applied across the membrane. Electrically charged particles (e.g. DNA) move in the electric field and block the ionic current as they pass through the nanopore. A sudden drop of the ionic current signals a single-molecule translocation event (Fig. 3-5). Nanopore sensors can give an information about the analyte: its size, structure and bonds stability. Today, a major topic of interest is the possibility of nanopore DNA sequencing.

In this work we present an introduction to nanopore technology and to current research related to potential nanopore applications. First, we describe biological and synthetic nanopores: their structure and methods of fabrication. Next, different modes of nanopore experiments are presented. In the third section, we focus on theoretical models and simulations of nanopores. Finally, we present future perspectives for applications with particular reference to DNA sequencing.

Keywords: nanopores, ion current, (bio)-polymer translocation, Poisson-Boltzmann equation, Poisson-Nernst-Planck equation, molecular dynamics


Wiadomości Chemiczne, 2013, 67, 277.
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SECONDARY PLANT METABOLITIES AS ANTIMICROBIAL AGENTS

Michalina Adaszyńska*, Maria Swarcewicz

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


One of the oldest achievements of the human thought is the use of plants and plant extracts in therapeutics. Drugs of a plant origin are characterized by multi-effects. In recent years, much interest was directed at medicinal plants containing a mixture of biologically active substances with antimicrobial properties. In medicine, for many years have been used substances extracted from plants and their secondary metabolites and plant extracts, but now due to the development of organic chemistry, pharmacology and medicine, we can determine which biologically active substances produced by these plants are useful. Antimicrobial activity were described for selected groups of plant secondary metabolites, which potentially would allow their use as antimicrobial substances in medicines. These substances can be complementary to basic medical treatment, because their main advantage is a lower incidence of side effects. This paper presents an overview of research on antimicrobial properties of alkaloids, coumarins, flavonoids, terpenoids and essential oils, phytosterols, and tannins and phenolic compounds. Examples of alkaloids active against strains of S. aureus, E. faecalis and E. coli are quindoline (1) and cryptolepine (2) which are components of an extract of Sida acuta [7]. Saal et al. described the effect of 7-amino-4-methylcoumarin (8) and daphnetin (9) isolated from Gingo biloba. These compounds are characterized by activity against strains of the genus S. aureus, E. coli and Salmonella entertidis [5]. Apigenin (15) and amentoflavone (16) have a strong activity against pathogenic fungi Candida albicans, S. cerevisiae, and T. beigelii. Terpenoids are potent phorbol esters (21-26), dustanine (27), 15-acetoxydustaine (28), cycloartenole (29) [14]. Several phytosterols has antibacterial activity [2, 5, 48]. The examples might be: stigmasterol (36), θ-sitosterol (37), epidoxysterol (38) isolated from Morinda citrifolia (Rubiaceae), which were characterized by strong activity against Mycobacterium intracellulare [5]. Many authors reported that the tannins and phenolic compounds were characterized by antimicrobial activity [49-53]. Natural substances that inhibit the growth of microorganisms are becoming an alternative to synthetic compounds, as this literature review confirms it.

Keywords: antimicrobial properties, secondary metabolites of plants, herbal medicines


Wiadomości Chemiczne, 2013, 67, 303.
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PERCUTANEOUS PENETRATION OF ACTIVE COSMETICS INGREDIENTS

Magdalena Malinowska, Elżbieta Sikora*, Jan Ogonowski

Instytut Chemii i Technologii Organicznej, Wydział Inżynierii i Technologii Chemicznej, Politechnika Krakowska, ul. Warszawska 24, 31-155 Kraków
*e-mail: esikora@pk.edu.pl


This article presents the science output regarding percutaneous transport mechanisms, penetration promotors and the methods of active substances skin absorption enhancement. The interaction between cosmetic ingredient and skin cells determines efficiency of the product. The study presents the most important functions of the skin outlayer (stratum corneum), its structure (Fig. 1) and permeability [1-7]. Due to the compact structure, stratum corneum prevents skin water loss. Moreover, it protects human body from outer substances influence [8-12]. Relationship between compound properties and its ability to skin absorption was also described. Physicochemical properties like lipophilicity, compound structure and particle size have a significant influence on intensity of the compounds skin penetration [4, 16-25]. Lipophilicity of a molecule is defined using many theoretical and experimental methods which allow to predict cosmetic ingredients assimilation [26-42]. Moreover, cosmetic base composition [43-47] and the presence of the penetration enhancers (promotors) also affect active ingredients absorption through the skin [48-49].

The most popular equipment used for testing the absorption and the penetration of active substances through the human skin are described in the last part of the manuscript. Compounds permeability through the skin could be tested using various experimental methods [50-58] including the diffusion cells equipped with membranes or prepared skin fragments [37, 55, 64-67]. The most common used are Franz diffusion cells (Fig. 4) and flow diffusion cell (Fig. 5). The measurement of permeation through stratum corneum using ATR-FTIR method is quite reliable and simple (Fig. 8), although measuring skin penetration is made by Saarbrucken penetration model (Fig. 6) and by application of Tape Stripping technique (Fig. 7). The study of skin absorption mechanisms and factors influencing this process is a great opportunity to design efficient cosmetic recipes and a possibility to make more effective, active cosmetic ingredients.

Keywords: percutaneous permeation, percutaneous absorption, diffusion cells


Wiadomości Chemiczne, 2013, 67, 321.
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ACTIVE INGREDIENTS OF PAINT REMOVER

Grzegorz Kurowski, Otmar Vogt*, Jan Ogonowski

Politechnika Krakowska, Wydział Inżynierii i Technologii Chemicznej, Instytut Chemii i Technologii Organicznej,
Katedra Technologii Organicznej i Procesów Rafineryjnych, ul. Warszawska 24, 31-155 Kraków
*e-mail: ozvogt@chemia.pk.edu.pl


In most of paint removers organic solvent are used as active ingredients. The analysis of the literature on modern manufacture preparations allowed to identify the most commonly used solvent for this purpose i.e. methylene chloride. Characterization of the advantages and risks associated with its use and the legal aspect of the use of this compound was described. Also the advantages and potential risks associated with the use of N-methylpyrrolidone were described. Substances from the group of alcohols, carbonates, carboxylic acid esters and derivatives of amides were also discussed. Compositions based on substances of natural origin and the solution involving biotechnological methods were presented. Developments in the production of such preparations were outlined.

Keywords: paint stripper


Wiadomości Chemiczne, 2013, 67, 345.
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THE EXPERIMENTS OF MICHAŁ JAN BORCH (1753-1811) CONCERNING CHEMILUMINESCENCE

Ignacy Z. Siemion1, Alicja Szastyńska-Siemion2

1 Wydział Chemii Uniwersytetu Wrocławskiego, ul. Joliot-Curie 14 , 50-383 Wrocław
2 Instytut Studiów Klasycznych, Orientalnych i Śródziemnomorskich , Uniwersytetu Wrocławskiego, ul. Szewska 49, 50-139 Wrocław


In the paper, the scientific activities of Polish scientist Michał Jan Borch (1753-1811) are briefly discussed, The Polish translation of Borch's article (published in "Atti dell' Academia della Scienza di Siena" in 1781) on the luminescence of the sea and different ideas on what could cause the phenomenon is presented. The attempts of Borch to isolate the luminescence - generating substance from decaying swordfish are discussed in the light of some later data on the chemiluminescence of organic compounds, Connected to bioluminescence experiments of our other scientists of that time (G. Forster and K. Kortum) are also quoted.

Keywords: M. Borch's scientific activity, sea luminescence, luminescence of decaying swordfish


Wiadomości Chemiczne, 2013, 67, 361.
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TRANS-1,2-DIAMINOCYCLOHEXANE - UNPRECEDENTED OUTSIDER'S CAREER

Małgorzata Petryk, Marcin Kwit*

Zakład Stereochemii Organicznej, Wydział Chemii Uniwersytetu im. Adama Mickiewicza, ul. Grunwaldzka 6, 60-780 Poznań
*e-mail: Marcin.Kwit@amu.edu.pl


An enantiopure trans-1,2-diaminocyclohexane is one of the most widely used chiral diamines in modern organic chemistry. This chiral building block, readily available from waste industrial products, emerges as a major figure in the field of asymmetric synthesis. The unique structural and conformational properties of trans-1,2-diaminocyclohexane make it very useful for the development of new synthetic strategies, taking advantage of its geometrical pre-organization. In this short article, we will highlight the utility of enantiomerically pure trans-1,2-diaminocyclohexane derivatives as broad-range chiral reagents and ligands for catalytic cycles. A brief overview of the aspects of applications in the field of molecular recognition will also be given.

Keywords: structure, chirality, conformation, asymmetric synthesis, molecular recognition


Wiadomości Chemiczne, 2013, 67, 393.
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CINCHONA ALKALOIDS - SMALL HARDWORKERS

Karol Kacprzak*, Paweł Czarnecki

Wydział Chemii UAM, ul. Umultowska 89B, 61-614 Poznań
*e-mail: karol.kacprzak@gmail.com


Cinchona alkaloids comprising quinine, quinidine, cinchonidine and cinchonine as the major members constitute a unique class of quinoline alkaloids with tremendous impact on human civilization (Section 1). The odyssey of Cinchona alkaloids began with the discovery of their antimalarial properties followed by antiarrhytmic action of quinidine. Currently medicinal chemistry of Cinchona alkaloids derivatives develops rapidly and many other activities such as cytotoxic, multidrug resistance inhibitory have been demonstrated (Section 5) [5]. Beside medicine Cinchona alkaloids gave also the fundaments of stereochemistry and asymmetric synthesis. An extraordinary catalytic potency of parent and modified Cinchona alkaloids (deserving privileged catalyst classification) include more than 50 types of diverse stereoselective reactions, with few spectacular such as asymmetric dihydroxylation of alkenes or heterogeneous α-ketoesters hydrogenation (Section 3) [3]. Last but not least the portfolio of applications of Cinchona alkaloids includes resolution of racemates by diastereomeric crystallization or by the use of Cinchona-based chiral stationary phases for ion-exchange enantioselective chromatography and other recognition or sensing systems (Section 4)[166]. Easy transformation of Cinchona alkaloids (for example by click chemistry) into other chiral and modular building blocks together with current pressure on a more intense exploration of sustainable products make cinchona alkaloids of primary importance for modern synthetic, catalytic and medicinal chemistry. The aim of this review which covers over 200 references is to briefly summarize all aspects of Cinchona alkaloid chemistry and biology with the special emphasis on new applications.

Keywords: quinine, cinchona alkaloids, quinidine, asymmetric synthesis, enantiomer separation, chirality


Wiadomości Chemiczne, 2013, 67, 443.
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TARTARIC ACID AND ITS DERIVATIVES IN CURRENT ORGANIC CHEMISTRY

Jakub Grajewski

Uniwersytet im. Adama Mickiewicza w Poznaniu, Wydział Chemii, Zakład Stereochemii Organicznej, ul. Grunwaldzka 6, 60-760 Poznań
e-mail: jakub.grajewski@amu.edu.pl


The tartaric acid and its salts have been present in chemistry for almost 350 years, since Pierre Seignette isolated Rochelle salt in 1675. Since that time tartaric acid and its derivatives have been often used in chemistry due to their accessibility, enantiopurity, relatively low cost and presence of different functional groups which easily allow to modify the molecule. Many tartaric acid derivatives serve as catalysts in important stereoselective transformations such as Sharpless asymmetric epoxidation or asymmetric Rousch aryloboronation. In many others reactions tartaric acid have been employed as a chiral building block for natural products synthesis, highly functionalized molecules or ligand design such as well known TADDOL or its analogues. Its polar functional groups allow to form crystals with amines and aminoalcohols what is widely used for their enantiopurification and resolution. The relatively new subdiscipline is the use of tartaric acid in chiral recognition and chiral discrimination in nanochemistry and enantioselective chromatography. The other, recent applications of tartaric acid include functionalization of metal layers, antibacterial and antifungal activity among many others. The significance of tartaric acid is evident - since 2000, words "tartaric acid" or "tartrates" can be found in databases over four thousand times. Taking that into account this short review is concentrated on selected applications of tartaric acid and its derivatives in organic chemistry in recent several years.

Keywords: tartaric acid, tartrates, stereochemistry, organic synthesis, catalysis


Wiadomości Chemiczne, 2013, 67, 495.
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ZINC-CATALYZED ASYMMETRIC HYDROSILYLATION OF KETONES AND IMINES

Jadwiga Gajewy

Zakład Stereochemii Organicznej, Wydział Chemii, Uniwersytet im. A. Mickiewicza, ul. Grunwaldzka 6, 60-780 Poznań
e-mail: gajewy@amu.edu.pl


One of the fundamental research goals in modern chemistry is the development of efficient and selective procedures to access organic compounds. Among all of the methodologies developed so far, catalysis offers an efficient and economical approach to enantiomericaly pure substances. In particular, transition metal catalysts modified by ligands, usually phosphines, are one of most successful examples of practical catalysis. Unfortunately, most of the applied metals (e.g., Pd, Rh, Ru, Ir) are low abundant, toxic and expensive. For this reason, recent research is focusing on their replacement by cheaper and low toxic metals. For example, the use of zinc can be of great interest, due to its abundance (0.0076% in the earth crust), biological relevance and distinct abilities. In the last two decades many scientific group have been working on finding new, high efficient and inexpensive catalytic system based on zinc for enantioselective transformations. It has been found that many of important organic reactions (for example aldol, Diels-Alder, Friedel-Crafts, Henry reactions) in their asymmetric version can be catalyzed by zinc complexes. One of them is also asymmetric reduction of double carbon-heteroatom bonds through addition of hydride (from silane). Hydrosilylation reduction is a promising alternative for the catalytic transformation of organic molecules to other reduction methods such as: hydrogenation and transfer hydrogenation owing to its operational simplicity and mild conditions. This review will give a general overview of the possible applications of zinc-catalyzed hydrosilylation of carbonyl compounds and imines. Since the understanding of mechanism of reaction is crucial for rational planning of new and more efficient ligands, some part of this article was devoted for mechanical considerations.

Keywords: asymmetric catalysis, hydrosilylation, zinc complexes, enantioselectivity, asymmetric activation


Wiadomości Chemiczne, 2013, 67, 521.
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BEAUTY OF CHEMICAL MOLECULES: SELF ORGANIZED COVALENT MOLECULAR CAGES

Paweł Skowronek Wydział Chemii UAM, ul. Grunwaldzka 6, 60-780 Poznań
e-mail: Pawel.Skowronek@amu.edu.pl


A short review of recent advances in synthesis of covalent cage molecules with an emphasis on their symmetry is presented in this publication. The idea of Dynamic Covalent Chemistry (DCC) as a tool to synthesize cage molecules is presented and explained. Among synthetic methods proposed by DCC the most frequently used to the synthesia of cage molecules is spontaneous reversible imination reaction. The role of symmetry and its entropy to lower total energy of cage molecules is discussed.

Keywords: macrocycle, cage compounds, reversible reactions


Wiadomości Chemiczne, 2013, 67, 563.
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ASYMMETRIC AZIRIDINE RING OPENING REACTIONS

Natalia Prusinowska

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


Aziridines, the nitrogenous analogues of epoxides, are useful building blocks for the synthesis of various functional materials and biologically active compounds. The reactivity of aziridines toward ring opening and expansion is dependent upon their extremely strained ring structures. Among the procedures of ring opening of aziridines, a nucleophilic ring-opening reaction is one of the major routes to highly functionalized compounds (Scheme 2). This short review focused on essentiac asymmetric ring opening reactions of aziridines including enantioselective ring opening of meso-aziridines and kinetic resolution of racemic aziridines with various hetero and carbon nucleophiles towards the synthesis of highly enantiomerically enriched 1,2-difunctionalized fine chemicals.

Keywords: aziridines, desymmetrization, asymmetric catalysis, kinetic resolution, ring opening reactions


Wiadomości Chemiczne, 2013, 67, 585.
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OKRUCHY XXVIII. Rozmyślania o czasie minionym

Ignacy Z. Siemion

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



Wiadomości Chemiczne, 2013, 67, 619.
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METHODS OF INVESTIGATION ENERGETICAL HETEROGENEITY ON THE SURFACE OF CATALYSTS AND ADSORBENTS

Piotr Woszczyński

Instytut Ciężkiej Syntezy Organicznej "Blachownia", ul. Energetyków 9, 47-225 Kędzierzyn-Koźle
e-mail: woszczyński.p@icso.com.pl


The knowledge of the properties and a surface structure of catalysts and adsorbents is of great importance in the selection of these materials to the relevant objectives. Interesting structural information can be obtained in many ways, for example: with the use of spectroscopic or microscopic techniques or in direct examination of the adsorption isotherms. This article focuses on these last-mentioned methods, which can be a source of information on energy heterogeneity of the catalyst or adsorbent surface.

Heterogeneity is usually determined by measuring adsorption isotherms of a selected adsorbate on the examined adsorbent, which is dependent of adsorbate coverage on the adsorbent relative to the equilibrium pressure under isothermal conditions.

Among the many mathematical models describing this relationship particularly interesting is the adsorption isotherm model described by generalized integral Fredholm equation. The solution of this equation is density function with the assumed local isotherm model. There are different ways to solve the Fredholm equation, depending on measurement methods of obtained adsorption isotherms. For example, an application of static techniques (gravimetric or volumetric) needs to use advanced, sophisticated numerical methods for directly solving integral equations, other techniques (e.g. such as calorimetric or chromatographic) provide specific values that simplify these calculations. The resulting energy density function allows to observe active centers as peaks or inflections of the curve on the energy spectrum graph.

Keywords: heterogeneity, adsorbent, catalyst, Fredholm equation, adsorption, calorimetry, chromatography, inverse gas chromatography (IGC), reverse-flow IGC (RF-IGC), programmed thermal desorption (TPD).


Wiadomości Chemiczne, 2013, 67, 635.
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MAGNETIC RESONANCE IMAGING CONTRAST AGENTS EXEMPLIFIED BY IRON COMPLEXES

Nikodem Kuźnik*, Marzena Wyskocka

Politechnika Śląska, Wydział Chemiczny,
Katedra Chemii Organicznej, Bioorganicznej i Biotechnologii, ul. B. Krzywoustego 4, 44-100 Gliwice
*e-mail: Nikodem.Kuznik@polsl.pl


Nuclear magnetic resonance is already a broadly exploited phenomenon both in chemistry and medicine. Magnetic resonance imaging is a routine technique in medical diagnosis readily applied for soft tissues like brain, cardiovascular system or gastrointestinal tract. Contrast agents stepped into the field and enabled better recognition of a lesion in the early stage of a disease.

The authors present an introductory description of a fascinating history, classification of contrast agents followed by the mechanisms of their action. Classes of positive and negative contrast agents are described. Further discussion is focused on the T1 (positive) molecular species. The mechanism was divided into (1) inner sphere, where both direct coordination of water molecule and its presence in second sphere is considered (Fig. 1) [1] and (2) an outer sphere mechanism which is assumed for the water molecules diffusing into the surrounding of the paramagnet [21, 28]. Further, the most important requirements for medical applications are given. Those are: high relaxivity, charge-osmolality, stability, toxicity via potential transmetallation of redox activity [42]. Molecular examples are quoted based on previously investigated iron complexes. Majority of them are iron(III) species [68], however, some iron(II) compounds like activable, self-immolative or ParaCEST systems have recently appeared [86, 89]. Iron compounds as positive contrast agents may soon accompany classic gadolinium complexes.

Keywords: magnetic resonance imaging, contrast agents, iron, relaxation


Wiadomości Chemiczne, 2013, 67, 665.
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SYNTHESIS OF SELECTED DRUGS 2-AMINO-1H-BENZIMIDAZOLE DERIVATIVES

Anna Nowicka, Wanda Paulina Nawrocka

Katedra i Zakład Technologii Leków, Uniwersytet Medyczny im Piastów Śląskich we Wrocławiu,
pl. Nankiera 1, 50-140 Wrocław
e-mail: anna.nowicka@am.wroc.pl


2-Amino-1H-benzimidazole fragment occurs in broad spectrum of drugs with anticancer, antiviral, antifungal, anthelmintic and antihistamine properties. There are 30 drugs, 2-amino-1H-benzimidazole derivatives, registered in the world.

Mebendazole, Albendazole and another derivatives are antihelmintic drugs which are believed to work by selectively inhibiting the synthesis of microtubules in parasitic worms, and by destroying extant cytoplasmic microtubes in their intestinal [9, 12, 14].

Astemizole was a second-generation antihistamine drug that has a long duration of action. It has been withdrawn from the market in most countries because of rare but potentially fatal side effects [19]. Mizolastine is non-sedating antihistamine drug [21]. It blocks H1 receptors and doesn't prevent the actual release of histamine from mast cells, but just prevents it binding to receptors.

Enviroksim and its isomer Zinviroksim and Enviraden are antivirial drugs [26, 27]. They inhibit multiplication of 15 different serotypes of rhinovirus.

Benomyl is a systemic fungicide that is selectively toxic to microorganisms [29]. Benomyl binds to microtubules, interfering with cell functions, such as meiosis and intracellular transportation. Carbendazim is a widely used, broad-spectrum fungicide and a metabolite of Benomyl [29]. It's also shown an anticancer activity.

Oncodazole shows antifungal, antineoplastic and antihelmintic activities, which exerts its effect in cells by binding to tubulin and interfering with the polymerization of microtubules [33].


Wiadomości Chemiczne, 2013, 67, 695.
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SELECTED METHODS OF THE SYNTHESIS OF 2-AMINO-1H-BENZIMIDAZOLE

Wanda Paulina Nawrocka, Anna Nowicka*

Katedra i Zakład Technologii Leków, Uniwersytet Medyczny im Piastów Śląskich we Wrocławiu,
pl. Nankiera 1, 50-140 Wrocław
*e-mail: anna.nowicka@am.wroc.pl


2-Amino-1H-benzimidazoles have attracted much attention due to their varied biological activities toward numerous diseases. 2-Amino-1H-benzimidazole core structures can be found in commercial drugs such as astemizole, mizolastine or carbendazime [1, 2]. 2-(N-substituted)-aminobenzimidazoles are widely used chemical substances in medicinal chemistry. Several compounds from this class have been used as anticancer, antihistamine and antiviral agents [3-5].

An efficient practical method for the synthesis of a diverse collection of 2-aminobenzimidazoles would be of great value for drug discovery. Several synthetic methods have been reported in the literature for the synthesis of 2-aminobenzimidazoles [11].

The synthesis of 2-aminobenzimidazole may be carried out in several ways. The most popular and economical method involves the treatment of various 2-substituted anilines with different cyclising agents to yield 2-aminobenzimidazoles. The cyclocondensation of an appropriate o-phenylenediamine with cyanogen bromide affords high yields of 2-aminobenzimidazoles [12]. Hydrogenation of o-cyanaminonitrobenzene over Raney nickel catalyst gives 2-aminobenzimidazole [34, 35]. Substituted 2-aminobenimidazoles have also been prepared by oxidation of the corresponding substituted thioureas with isothiocyanates using desulfurizing agents such as mercury-(II) oxide or methyl iodide [18-21].

Keywords: 2-amino-1H-benzimidazole, alkyl and aryl derivatives, synthesis


Wiadomości Chemiczne, 2013, 67, 715.
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A SHORT HISTORY OF SOME FORMULAS

Wojciech Kroszczyński

Instytut Chemii, Uniwersytet Przyrodniczo-Humanistyczny, ul. 3 Maja 54, 08-110 Siedlce
e-mail: w.kroszczynski@gmail.com


This article is an attempt to present how the classical detective work has been performed in order to determine chemical structures. In the past, discussion on these examples was the way of learning of the organic chemistry. Thermal degradation was the main method of analysis currently replaced with the spectroscopy. Perhaps the history of chemistry may help to understand mentalities of creators of new branches of science. On the other hand, it gives arguments for a cultivation of "impractical" sciences.

The article describes the earliest attempts to present simple organic formulas undertaken by Couper and Kekulé. Examples of a transformation of aromatic compounds present how results of derivatization led to conclusions concerning structures. Experiments and logic line of thought was supported by a great intuition. More complicated molecules were investigated by degradation reactions. For example, A. Baeyer at the beginning of his investigations concerning indigo, subjected isatin (obtained from indigo by oxidation) to different reducing reagents. He obtained indoldiol, oxindole, indole etc. Then these relatively simple compounds were synthesized and served as by-products for indigo. Some methods of the industrial production of indigo were elaborated on the base of works of Baeyer [16-20]. Similarly, the structures of chrysin, brazilin and haematoxilin have been resolved mainly by their degradation. The final structures were confirmed by synthesis.

Keywords: brazilin, chrysin, haematoxilin, history of chemistry, indigo, salicylic acid


Wiadomości Chemiczne, 2013, 67, 733.
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ENANTIOSELECTVE ENZYMATIC DESYMMETRIZATION CATALYZED IN THE PRESENCE OF LIPASE. PART I. PROCHIRAL COMPOUNDS

Renata Kołodziejska*, Aleksandra Karczmarska-Wódzka*, Agnieszka Tafelska-Kaczmarek**, Renata Studzińska*, Marcin Dramiński*

* Katedra i Zakład Chemii Ogólnej, Collegium Medicum w Bydgoszczy UMK Toruń, ul. Dębowa 3, 85-626 Bydgoszcz
** Katedra Chemii Organicznej, UMK Toruń, ul. Gagarina 7, 87-100 Toruń
Katedra i Zakład Chemii Ogólnej, Collegium Medicum w Bydgoszczy, UMK Toruń, ul. Dębowa 3, 85-626 Bydgoszcz


In the enzymatic asymmetric synthesis, the enzyme allows the desymmetrization of achiral compounds resulting in chiral compounds of high optical purity. Therefore, this type of biotransformation is known as enantioselective enzymatic desymmetrization (EED) [1-11]. This method is related to the generation of an asymmetry (loss of symmetry elements) in prochiral molecules (most often an sp3 or sp2 hybridized carbon atom), in meso synthones, and centrosymmetric compounds. An achiral center of the tetrahedral system is defined as a prochiral one if it becomes chiral as a result of one of the two substituents replacement which, when separated from the particles, are indistinguishable (Scheme 1, 2) [1-4, 9, 12].

Asymmetric synthesis is enantioselective when one of the enantiotopic groups or faces of an optically inactive compound is biotransformed faster than the other (Scheme 3-5) [1, 10, 11, 13-15].

Lipases are enzymes of highest importance in stereoselective organic synthesis, mainly due to their exceptionally broad substrate tolerance, stability, activity in unphysiological systems, and relatively low price [9, 14]. The mechanism of enzymatic hydrolysis catalysed by hydrolases is similar to that observed in the chemical hydrolysis with the use of base. The selectivity of enzymatic catalysis depends on the substrate orientation in the enzyme active site (Scheme 6, 7) [25-29].

Lipases were successfully used for the desymmetrization of different prochiral diesters, alcohols and amines. Most lipases preferentially convert the same prochiral groups in the above mentioned types of reaction. This allows the preparation of the both enantiomers of the product in high chemical and optical yield (Scheme 9-13) [9, 13, 32-56].

Keywords: prochiral compounds, desymmetrization, transesterification, hydrolysis, lipase


Wiadomości Chemiczne, 2013, 67, 751.
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OKRUCHY XXIX. O MOICH KSIĄŻKACH

Ignacy Z. Siemion

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



Wiadomości Chemiczne, 2013, 67, ??.
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Wspomnienia o Profesorze Hubercie Kołodzieju

Kazimierz Orzechowski

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


Wiadomości Chemiczne, 2013, 67, 799.
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PROLINE AS A COMMON AMINO ACID AND AN EXCEPTIONAL CATALYST. PART I.
PROLINE BIOSYNTHESIS. INTRAMOLECULAR ALDOL REACTION

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

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


In asymmetric synthesis of organic compounds more effective solutions are being looked for which will result in higher yield(s) of product(s) and their high enantioselectivity [1]. One of such solutions is an use of a multilevel and cheap catalyst. Proline used as a catalyst is a substance of natural origin which was synthetically obtained by Willstätter who was carrying out research on hygric acid (Scheme 1) [10]. The cells of many organisms have a suitable enzymatic system essential for proline biosynthesis [15]. So far, three proline biosynthesis pathways have been described: from glutamate (Scheme 3 and 4), ornithine (Scheme 5 and 6), and arginine (Scheme 7) [16-28]. Proline which is obtained as a result of biosynthesis or supplementation is a substrate for many proteins. Characteristic and significant content (about 23%) of this amino acid was observed in collage. In cells proline can play an important role of osmoregulator [31-35] - a protective substance regulating the activity of such enzymes as catalase and peroxidase [36]. Proline as a secondary amine shows exceptional nucleophilicity facilitating imine and enamine formation. Used as a catalyst in aldol reaction makes with substrates like imine or enamine transition state imitating the activity of naturally occurring enzymes for this type of reaction, that is aldolases. In their research Hajos and Parrish, and Eder, Sauer and Wiechert used proline in intramolecular aldol reaction obtaining proper enones (Scheme 9) [60-62]. The process of intramolecular aldol reaction was used for a separation of racemic mixture of diketones (Scheme 10) [63, 64], cyclization of ortho-substituted aromatic aldehydes and ketones (Scheme 11) [65], synthesis of cyclic diketones (Scheme 13) [68] and domino reaction to obtain substituted cyclohexanones from beta-diketones and unsaturated ketones (Scheme 14) [69].

Keywords: proline biosynthesis, mechanism of aldol reaction, intramolecular aldol reaction


Wiadomości Chemiczne, 2013, 67, 801.
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ENANTIOSELECTVE ENZYMATIC DESYMMETRIZATION CATALYZED IN THE PRESENCE OF LIPASE. PART II. OPTYMALIZATION OF REACTION CONDITIONS. MESO COMPOUNDS

Aleksandra Karczmarska-Wódzka1, Renata Kołodziejska1,, Agnieszka Tafelska-Kaczmarek2, , Tomasz Przybyła, Marcin Dramiński1

1, Katedra i Zakład Chemii Ogólnej, Collegium Medicum w Bydgoszczy UMK Toruń, ul. Dębowa 3, 85-626 Bydgoszcz
2, Katedra Chemii Organicznej, UMK Toruń, ul. Gagarina 7, 87-100 Toruń


In the enzymatic asymmetric synthesis, the enzyme allows the desymmetrization of achiral compounds resulting in chiral compounds of high optical purity. Meso compounds (bearing a plane of symmetry) are very important group of compounds used in EEDs (Scheme 1) [1-4]. Similarly to prochiral compounds, selective acylation or hydrolysis of meso substrates leads to optically active products. Most lipases preferentially convert the same enantiomers in the above mentioned types of reaction. This allows the preparation of the both enantiomers of the product in high chemical and optical yield (Scheme 3-20) [35-58].

An effective enzymatic catalysis should be performed under conditions optimal for a biocatalyst performance. Hence, it is essential to select an appropriate reaction medium, the pH, and temperature [6-34].

Optimization of the reaction conditions in terms of an appropriate solvent selection is effective and most frequently the simplest way to modify the enzyme selectivity. One of the most important criteria for the solvent selection is its nature [25]. The enzyme selectivity is conditioned by its conformational rigidity, which increases in more hydrophobic medium (typical hydrophobic solvents, scCO2). A hydrophobic solvent decreases biocatalyst lability, which does not allow the connection between the structurally mismatched substrate and the active side of an enzyme [10, 26-31]. Ionic liquids are a separate group of solvents which, despite their high hydrophobicity (logP << 0) and polarity, can constitute an ideal medium for the biotransformation reactions [18-23].

Keywords: meso compounds, desymmetrization, transesterification, hydrolysis, lipase


Wiadomości Chemiczne, 2013, 67, 819.
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MITSUNOBU REACTION - MECHANISM AND APPLICATION

Joanna D. Kitkowska*, Żaneta A. Tabaczyńska, Marcin Dramiński

Katedra i Zakład Chemii Ogólnej, Wydział Lekarski, Collegium Medicum Uniwersytet Mikołaja Kopernika, ul. Dębowa 3, 85-626 Bydgoszcz
*e-mail: j.kitkowska@cm.umk.pl


The Mitsunobu reaction has been known since 1967, but the research on its modifications as well as on the introduction of new reagents, productivity, improvement and methods of post-reaction mixture separation is still being conducted. The original reaction was used to obtain esters by condensation of carboxylic acids and alcohols using triphenylphosphine and DEAD mixture. This reaction allows formation of s not only carbon-oxygen bond, but also carbon-carbon, carbon-nitrogen, and carbon-sulphur to be synthesized. The Mitsunobu reaction is widely applied in organic synthesis as a way of inversion of configuration of secondary alcohols or of aryl ethers synthesis. Numerous studies bring the accounts of using this reaction for the synthesis of steroids, carbohydrates, nucleosides, as well as alkaloids and other heterocyclic compounds containing nitrogen. The popularity of this reaction lies in its stereoselectivity and compatibility with a wide range of functional groups as well as in its moderate requirements considering reaction conditions. However, an isolation of a desirable product from the used up or surplus reagents still causes a lot of difficulties.

Keywords: Mitsunobu reaction, condensation, configuration inversion, stereoselectivity


Wiadomości Chemiczne, 2013, 67, 843.
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BIOACTIVE N-ACYLPHOSPHORAMIDATE NUCLEOSIDE DERIVATIVES

Katarzyna Kulik

Centrum Badań Molekularnych i Makromolekularnych w Łodzi, Polska Akademia Nauk, ul. Sienkiewicza 112, 90-262 Łódź, Poland
e-mail: kpieta@cbmm.lodz.pl


Natural nucleotide antibiotics such as Agrocin 84, Dinoguellin, Microcin C and Phosmidosine have a N-acylphosphoramidate linkage at the 5'-hydroxyl of the adenosine derivatives (Fig. 1, 2) [1-3]. They exhibit interesting antifungal, antiemetics and anticancer properties. To synthesize these products, the construction of the N-acylphosphoramidate linkages seems to be a key step. Many groups have described the preparation of such a type of analogues but none of those methods was general. Grandas has for the first time reported the synthesis, of N-acylphosphoramidate peptide-oligonucleotide hybrids via condensation of N-phosphitylated carboxyamides with alcohols in the presence of 1H-tetrazole [9]. Based on this strategy Sekine synthesized aminoacyl adenylate (aa-AMP) analogues which could be useful in the studies on the recognition mechanism of the aminoacylation of tRNA and other biochemical reactions [10]. Since aa-AMPs are extremely unstable under aqueous conditions more stable analogues were required. Aminoacyl-adenylate analogues having an N-acylphosphoramidate linkage (aa-AMPN) could behave as potent, selective asparagine synthetase (AS) inhibitors because of its structural similarity to β-aspartyl-AMP (βAspAMP) which is natural product of AS [17].

Among natural N-acylphosphormiadates, Phosmidosine which connects a nucleoside analogue, 8-oxoadenosine, with an L-proline residue is unique because of its significant antitumor activities and property of stopping cell growth at the G1 phase in the cell cycle (Fig. 2) [2, 13]. The main difficulty during the synthesis of this compound is an extreme instability under weak basic conditions which excludes the use of labile protecting group of basic properties [14]. Stability studies have shown that under basic conditions phosphoryl group of Phosmidosine underwent rapid N-N migration (Scheme 9) [16]. Many modifications have been introduced to improve Phosmidosine properties [16]. Analogues such as demethylated species (Phosmidosine B) have proven to be stable under both basic and acid conditions and are also potential candidates for antitumor drugs [14].

Keywords: N-acylphosphoramidate function, aminoacyl adenylate analogues, nucleoside analogue, Phosmidosine


Wiadomości Chemiczne, 2013, 67, 877.
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TWO-DIMENSIONAL SEPARATION WITH CHROMATOGRAPHY AND ELECTROPHORESIS TECHNIQUES WITH SPECIAL FOCUS ON THEIR COMBINATION INTO SINGLE PROCESS

Eryk Łopaciuk*, Tadeusz H. Dzido

Zakład Chemii Fizycznej, Katedra Chemii, Uniwersytet Medyczny w Lublinie, ul. Chodźki 4A, 20-093 Lublin
e-mail*: eryk.lopaciuk@umlub.pl


Liquid chromatography and electrophoresis techniques are very often applied in contemporary laboratory practice. These techniques usually show different separation selectivity. It is due to various separation mechanisms involved in these two modes. In the former, partition of solutes between stationary and mobile phases influences on separation selectivity and retention contrary to the latter in which electrophoretic effect is involved in separation mechanism. The features mentioned are very useful for combination of these two techniques into two-dimensional separation of complicated samples of biomedical and environmental origin. Development of such approach is a very promising for contemporary separation sciences.

The paper presents an overview of two-dimensional separation techniques, in which both liquid chromatography and electrophoresis have been involved especially in continuous mode.

Keywords: two dimensional separation, electrophoresis, electrochromatography, liquid chromatography, continuous two-dimensional separation


Wiadomości Chemiczne, 2013, 67, 899.
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SCHERRER FORMULA - THE CENTURY OF ERRONEOUS PRACTICES

Paweł E. Tomaszewski

Instytut Niskich Temperatur i Badań Strukturalnych, Polska Akademia Nauk, P. Nr 1410, 50-950 Wrocław 2
e-mail: p.tomaszewski@int.pan.wroc.pl A


We present the sources of uncertainty in the evaluation of grain size in nanomaterial. The calculations are made for the same diffraction pattern using Scherrer and Williamson-Hall methods. As an example we use the CoCr2O4 nanocrystal. The comparison of results from different calculations, methods and programs is made just to show how important is the (correct) choice of a method and its internal parameters. The data from well known Scherrer formula, show that the difference in obtained results exceeds 100% up to even about 350%. This indicates that in any case the Scherrer formula could not give the correct and reliable value for crystallite size. As a consequence, the wide use of this formula is a great error providing the incorrect results.

Keywords: Scherrer formula, nanomaterials, diffraction studies, grain size


Wiadomości Chemiczne, 2013, 67, 929.
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SYNTHESIS OF γ-LACTONES WITH AROMATIC SUBSTITUENTS

Andrzej Skrobiszewski*, Witold Gładkowski

Uniwersytet Przyrodniczy we Wrocławiu, Katedra Chemii, ul. C.K. Norwida 25/27, 50-375 Wrocław
*e-mail: andrzej.skrobiszewski@gmail.com


Biological activities of lactones are predominantly determined by different substituents on a lactone ring. γ-Lactones with aromatic substituents have interesting biological activities and serve as useful intermediates in the synthesis of many natural and synthetic products. Pulvinic and vulpinic acids exhibit antimicrobial, antioxidant and anticancer activity [1-3]. Paraconic acids have anticancer and antibacterial activity [4, 5]. The interesting biological activities i.a. antileukemic, anti-HIV and cytostatic, have been found for dibenzyl-γ-lactones [8].

This review covers some examples of synthetic and biotechnological methods leading to either racemic or optically active γ-lactones with aromatic substituents. The racemic α-benzylidene lactones can be produced from Baylis-Hillman acetates [9]. The multicomponent synthesis of the paraconic acid analogs is performed by a fourfold metallation-conjugate addition-aldol addition-intramolecular transesterification sequence [4]. Suzuki-Miyaura reaction is the key step in the synthesis of asymmetric pulvinic acids [1]. Some other examples of synthetic strategies involving the reactivity of ylides, vicinal dianions, ozonolysis or Claisen rearrangement are also presented [10-13].

Production of optically active γ-lactones with aromatic substituents involves application of biotechnological and chemical methods. The first one includes using commercially available enzymes [16, 17] or whole cells of microorganisms [18-20]. Chemical methods involve application of chiral starting materials like malic acid esters or the derivatives of succinic acid [14, 15] or chiral catalysts like BINAP-Rh or Ru complexes [7].

Keywords: γ-lactones, aromatic rings, Suzuki-Miyaura reaction, enzymatic hydrolysis and acetylation, microbial reduction of a carbonyl group, diastereoselective alkylation, enantioselective hydrogenation of olefinic substrates


Wiadomości Chemiczne, 2013, 67, 943.
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OKRUCHY XXX. O TAJEMNICY ZAWARTEJ W "PAMIĘTNIKU ZNALEZIONYM W SARAGOSSIE" JANA POTOCKIEGO

Ignacy Z. Siemion

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



Wiadomości Chemiczne, 2013, 67, 961.
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CURRENTLY AVAILABLE SURFACTANTS AND THEIR MICELLAR STRUCTURES FORMED IN AQUEOUS SOLUTIONS

Anna Jakubowska

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


This article presents currently available surfactant ionic liquids as well as functionalized and polymeric surfactants.

Ionic liquids (ILs) are organic salts of melting points below 100°C. They have attracted much attention due to their unique physicochemical properties such as low volatility, high thermal stability, low toxicity, high ionic conductivity, capacity to dissolve organic, inorganic and polymeric materials [1]. ILs can be used as "green" solvents in electrochemistry, extraction, chromatography, catalysis, chemical and enzymatic reactions, and synthesis of new materials [2-4]. Ionic liquids are less corrosive than classical molten salts and therefore are used as electrolytes in batteries or solar cells [5].

Like other salts, ionic liquids are formed by ions but at least one of them is an organic ion. Moreover cations and anions differ significantly in their geometrical characteristics [1]. ILs with long alkyl chains and pronounced hydrophilic and lipophilic molecular fragments have an obvious amphiphilic nature and are called the surface active ionic liquids, SAILs, because they show combined properties of ILs and surfactants [6].

Recently, there is ever-increasing interest in SAILs based on gemini surfactants (Figs 6 and 7 [21, 22]), dodecyl sulfate, DS (Fig. 8a) and aerosol-OT, AOT (Fig. 8b) anions [23-25], alkylpyridinium (Fig. 1b [11]), imidazolium (Figs 1a and 3 [13, 14, 16]), alkylpyrrolidinium [17, 18], and diisopropylethylammonium, DIPEA [19] cations. Apart from SAILs, in recent years an attention has also been paid to functionalized surfactants such as: bolaform surfactants [32], supra-long chain surfactants [35, 36], calixarene-based surfactants (Fig. 9 [33]). Surfactants of the above types of SAILs and functionalized surfactants have been synthesized and their micellar structures formed in water have been studied. For example, very interesting vesicle systems were observed in aqueous solutions of diisopropylethylamine alkyl carboxylates, [DIPEA]+[CnH2n+1COO]-, for n = 3-9 (Fig. 5 [19]) and in aqueous solutions of the surfactant mixture composed of N-dodecyl-N-methyl-pyrrolidinium and sodium dodecyl sulfate (Fig. 4 [18]). It was found that 1-hexadecyl-3-methyl-imidazolium chloride in aqueous solutions underwent the phase (micellar) transformations upon cooling (Fig. 2 [13]).

An important group of polymeric surfactants attracting a great interest in literature is that of triblock copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO), often abbreviated as [EO]a-[PO]b-[EO]a. Recently, these copolymers, also called poloxamers, have been proposed for pharmaceutical use [37-40]. These nonionic surfactants form micelles in aqueous solutions with a core containing the hydrophobic PO blocks and a shell made up of the hydrated EO blocks [41]. The subject of current studies include: the interactions between poloxamers and anionic surfactant, SDS in aqueous solutions [42-47], micellization of poloxamers in mixtures of water and organic solvents [48], comparison of association properties of diblock and triblock copolymers [49].

The paper also presents the experimental methods used recently to study surface activity, aggregation behaviors, and micellar structures of surfactants in water.

Keywords: surfactants, ionic liquids, functionalized surfactants, polymeric surfactants, measurement techniques, micellar structures


Wiadomości Chemiczne, 2013, 67, 981.
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MODIFIED OLIGODEOXYRIBONUCLEOTIDES CONTAINING NITROGEN AT A BRIDGING POSITION OF AN INTERNUCLEOTIDE BOND

Ewa Radzikowska

Centrum Badań Molekularnych i Makromolekularnych Polskiej Akademii Nauk, Zakład Chemii Bioorganicznej, ul. Sienkiewicza 112, 90-362 Łódź
e-mail: eradziko@bio.cbmm.lodz.pl


Synthetic oligonucleotides (ONs) constitute an important class of compounds which exhibit biological activity. As potential drugs ONs are employed in the antisense strategy [1]. The antisense therapeutic agent acts on the pathogenic mRNA causing inactivation of the target. Ideal antisense agent should be resistant to exo and/or endonucleases, have a suitable pharmacological and pharmacokinetic profile and high affinity for the target. To improve some properties of antisense oligonucleotides plethora of chemical modifications introduced within both sugar unit and internucleotides linkage were investigated.

Among numerous ONs modified in internucleotide phosphodiester bond, one of the most interesting are oligonucleotide phosphoramidates (NP-oligos) in which one of the bridging oxygens is replaced by nitrogen atom (at 3' or 5' position). Hence, two classes of compounds are formed: oligonucleotide-(N5'→P3')phosphoramidates and oligonucleotide(N3'→P5')-phosphoramidates. These compounds, similar to native DNA and RNA, possess an achiral phosphorous atom and all internucleotides bonds are negatively charged. Additionally, NP-oligo shows good resistance to nucleolyticdegradation and can bind to the target DNA or RNA with high affinity [12]. In literature several synthetic strategies concerning both (N5'→P3') and (N3'→P5') NP-oligos have been described. Some of them allowed to obtain only corresponding dimers.

In the light of recent discoveries the most promising candidates for therapeutic and diagnostic applications are oligonucleotide-(N3'→P5')thiophosphoramidates. Gryaznov et al. have found that such compounds can act as potent and selective telomerase inhibitors [29]. Human telomerase (TA) is a reverse transcriptase ribonucleoprotein that synthesizes de novo d-(TTAGGG)n repeats at chromosomal DNA ends. Whereas activity of this enzyme is observed in ~85% of all human tumors, most of normal somatic cells either lack TA activity or express it only at low levels. For these reasons TA constitute an attractive and nearly universal anticancer target for rational drug development.

Keywords: nucleic acids analogues, internucleotide linkage modifications, oligodeoxyribonucleoside-(P3'→N5')phosphoramidates, oligodeoxyribonucleoside- (N3'→P5')(thio)phosphoramidates, antisense strategy, telomerase, Atherton-Todd reaction


Wiadomości Chemiczne, 2013, 67, 100.
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PROLINE AS A COMMON AMINO ACID AND AN EXCEPTIONAL CATALYST. PART II. INTERMOLECULAR ALDOL REACTION

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

Katedra i Zakład Chemii Ogólnej Uniwersytetu Mikołaja Kopernika, Collegium Medicum w Bydgoszczy, ul. Dębowa 3, 85-626 Bydgoszcz
e-mail: renatakol@poczta.fm


Proline in organic synthesis is used as a small molecular organocatalyst. In a catalytic act proline, similarly to an enzyme, activates reagents, stabilizes transition state and influences an orientation of substrates [1-12]. Proline works as aldolase I (so called microaldolase I). In comparison with other amino acids it shows exceptional nucleophilicity which makes imines and enamines formation easier.

In the intermolecular aldol reaction proline was used for the first time by List and co-workers (Scheme 1) [3, 9, 20]. Since then an immense progress has been observed in this field. Several aldolization reactions were performed in the presence of proline. Reactions of this type proceed between the donor (nucleophile) and the acceptor (electrophile).

In aldol reaction the donors can be both ketones and aldehydes which next are condensed with ketones and aldehydes acting as electrophiles (Scheme 2-18; Tab. 1-7) [21-72]. The presence of proline ensures not only high yield of homo- and heteroaldolization but mainly enables conducting enantio- and diastereoselective synthesis. Intermolecular proline-catalyzed aldol condensation proceeds according to enamine mechanism. Anti-aldols, which make a valuable source of intermediates in the synthesis of important biologically active compounds, are mainly obtained in this reaction [35-44, 54, 58, 62, 63, 68, 69, 71].

Keywords: intermolecular aldol reaction, donor, acceptor, proline, anti-aldol


Wiadomości Chemiczne, 2013, 67, 1027.
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BIOLOGICAL ACTIVITY OF THIAZOLO[4,5-d]PYRIMIDINE DERIVATIVES

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


Thiazolo[4,5-d]pyrimidine is one of the six structural isomers of the bicyclic ring system containing thiazole moiety fused with the pyrimidine. There are six structural isomers depending on the position of the nitrogen atoms. The isomer [4,5-d] does not contain the bridge-head nitrogen and can be considered as 7-thio analogue of the natural purine bases such as guanine and adenine. Due to the great of their biological potential the newly synthesized compounds are evaluated for various pharmacological activities. This review presents numerous thiazolo[4,5-d]pyrimidine derivatives reported for their interesting biological activity including antibacterial [2, 3, 5, 7, 8, 10, 19], antifungal [2-6, 9, 10], antiviral [11-13], analgesic [18, 19], antidepressant [17] and anticancer properties [23-26]. Some urea and thiourea derivatives exhibited significant antiparkinsonian activity [14-16]. Tumor necrosis factor (TNF) promotes an inflammatory response, which in turn causes many of the clinical problems associated with autoimmune disorders. Ethyl 4-(2-amino-5,7-dioxo-3,4,5,7-tetrahydro-thiazolo[4,5-d]pyrimidin-6(2H)-yl)butanoate derivatives 29 (Fig. 24) as a TNFα inhibitors have a potential use in the treatment of diseases such as refractory asthma, psoriasis, rheumatoid arthritis, irritable bowel syndrome, and other [21]. Blocade of the CXCR2 receptor by thiazolo[4,5-d]pyrimidine-2(3H)-ones also represents an attractive strategy for treatment of inflammatory diseases [20]. Recently there have been developed CX3CR1 receptor antagonists for the treatment of multiple sclerosis [22]. Isatoribine, 5-amino-3-β-D-ribofuranosyl-3H-thiazolo[4,5-d]pyrimidin-2-one (20) (Fig. 15) is a small molecule toll-like receptor 7 (TLR7) agonist and an activator of innate immunity. Its orally bioavailable analogue ANA 975 (Fig. 16) has been reported for probable use in treating disease states associated with abnormal cell growth, such as cancer and has anti HCV activity [13]. Thiazolo[4,5-d]pyrimidines inhibit the growth of the weeds which implies that they have a potential as herbicides [27].

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


Wiadomości Chemiczne, 2013, 67, 1051.
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SYNTHESIS OF PYRAZOLO[4,3-c]HETEROCYCLIC DERIVATIVES

Anna Wójcicka

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


The broad spectrum of biological activity of pyrazolo[4,3-c]heterocyclic derivatives is the main of reason for the preparation of new compounds containing this scaffold. This review presents most of the literature data on the synthesis of pyrazolo[4,3-c]heterocyclic derivatives. This isomer system containing pyrazole moiety condensed with a heterocyclic ring can be synthesized from a different substrates, but that synthesis may be classified into two main categories: annulation of the pyrazole ring onto heterocyclic derivatives or annulation of the heterocyclic ring onto pyrazole analogs. The main goal of this study is the presentation of various methods for the preparation of the pyrazolo[4,3-c]pyridine (Rys. 2) [1-15], pyrazolo[4,3-c]quinoline (Rys. 3) [16-63], pyrazolo[4,3-c]isoquinoline [64, 65], pyrazolo[4,3-c]naphthtyridine [66-68], pyrazolo[4,3-c]thiazine [69-72], pyrazolo[4,3-c]cinnoline [73, 74], pyrazolo[4,3-c]quinolizine [75], and pyrazolo[4,3-c]pyridazine [76] derivatives.

Keywords: pyrazolo[4,3-c]heterocyclic derivatives, pyrazolo[4,3-c]pyridine, pyrazolo[4,3-c]quinoline, pyrazolo[4,3-c]naphthyridine, synthesis


Wiadomości Chemiczne, 2013, 67, 1075.
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THE MECHANISM OF RESISTANCE TO PLATINUM DRUGS AND STRATEGIES TO OVERCOME THIS PHENOMENON

Wanda Weiss-Gradzińska, Wojciech Krzempek, Lilianna Trynda-Lemiesz*

Uniwersytet Medyczny im. Piastów Śląskich we Wrocławiu, Katedra i Zakład Chemii Analitycznej, ul. Borowska 211 A, 50-566 Wrocław
*e-mail: lilianna.trynda-lemiesz@am.wroc.pl


Platinum drugs belong to one of the oldest [2] and best investigated groups of cytotoxic drugs. On account of their high efficacy and alkylating-like action [14] they are used in a treatment of various types of neoplasms [3-5]. Despite investigators' best efforts survival time of patients diagnosed with cancer is still short. Responsible for the fact is high toxicity of used therapeutic methods and development of resistance to them [3-5, 19]. In this paper authors review reasons behind decreased sensitivity of neoplastic cells to platinum treatment and discuss the newest promising trends in its overcoming.

Due to different properties of neoplastic cells, availability of a chemotherapeutic agent inside a tumour is limited [9-12]. Moreover continuous development of resistance to platinum drugs further decreases their cellular concentration and inactivates their functions. Also owing to increased activity of DNA repair systems, higher tolerance to genome deformations and numerous mechanisms that lead to impaired apoptosis, drug efficacy is reduced [3-5, 19].

In order to increase a potency of platinum agents new therapeutic strategies are investigated. Coadministration with resistance modulators [20, 22, 23] and combination therapy with other antineoplastic drugs [8, 24-30] have already proved their effectiveness. Additionally, newer generations of platinum drugs are developed [15-18]. Mostly platinum(IV) prodrug complexes often releasing axial ligands with their own pharmacological action [5, 6, 31], but also multi-nuclear platinum compounds that form more complex DNA-adducts [32-35]. Other strategies include the development of innovative dosage forms such as single walled carbon nanotubes (SWCNTs), multiwalled carbon nanotubes (MWCNTs) [38, 39] or encapsulation [36, 37]. Finally utilisation of oncolytic viruses could be a way to selectively destroy neoplastically transformed cells [40].

Keywords: platinum drugs, drug resistance, cancer therapy, influx, efflux, carbon nanotubes, cisplatin


Wiadomości Chemiczne, 2013, 67, 1105.
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INFLUENCE OF BREWING CONDITIONS ON ANTIOXIDANT CONTENT IN DIFFERENT KINDS OF TEA INFUSIONS

Kamil Kurleto*, Grzegorz Kurowski, Barbara Laskowska, Magdalena Malinowska, Elżbieta Sikora, Otmar Vogt

Wydział Inżynierii i Technologii Chemicznej, Politechnika Krakowska ul. Warszawska 24, 31-155 Kraków
*e-mail: kurleto@chemia.pk.edu.pl


Tea has been consumed all over the World for over two thousand years and now it is the most popular caffeine-containing beverage. Its worldwide consumption is second only to water [1-3]. The tea is not only important because of its popularity but also due to its beneficial influence on human health [4]. The biological benefits of tea are due to their flavanol content[5-13]. Tea flavanols are a group of natural polyphenols (Fig. 2). Therapeutic effects of tea have been extensively examined in many in vitro and in vivo tests. It was confirmed that tea leaves ingredients have antibacterial, antifungial, antiviral properties, they also prevent cell mutations and they inhibit progress of heart diseases. Moreover, tea can stimulate neural system and regulate its functions [14-20]. All this activities are mostly due to antioxidant ability of tea polyphenols (Fig. 4).

Tea production process can be run in different ways and this affects of the tea taste, aroma, colour and antioxidants content. According to fermentation degree, different tea kinds can be obtained (Fig. 1). During the manufacturing process of black and oolong teas, tea leaves are crushed to allow polyphenol oxidase to catalyze the oxidation and polymerization of catechins to polymers called theaflavins and thearubigins (Fig. 3) [21-23]. Green or white teas are obtained through shorter fermentation, so the catechin concentration remains higher. Tea is prepared by infusing tea leaves in hot water. Brewing process conditions like temperature, brewing time, pH, besides other factors has a significant influence on polyphenols content [24-32]. Many studies have determined total flavonoids content and antioxidant activity according to different tea type and brewing conditions, tea plantation type or fermentation process. The amount of total polyphenol was determined using the F-C method, catechins, caffeine and polyphenolic acids were analysed using High Performance Liquid Chromatography with reversed phase. Obtained results let compare how different production and brewing processes affect the tea quality [33-56].

Keywords: tea, antioxidants, total antioxidant capacity


Wiadomości Chemiczne, 2013, 67, 1129.
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