Wiadomości Chemiczne

Wiadomości Chemiczne, 2006, Vol. 60

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  1. Dihydroxyacetone Phosphate in Chemistry and Biochemistry
    Katarzyna Ślepokura, Tadeusz Lis

  2. Silicoaluminophosphates and their Selected Applications
    Rafał Łużny, Jerzy Walendziewski

  3. Methods of 90Sr Analysis in Evironmental Samples
    Jan Solecki

  4. Formaldehyde in Air-Sources, Toxicology and Methods of Removal from Indoor Air
    Irena Jacukowicz-Sobala, Elżbieta Kociołek-Balawejder

  5. Microwave Digestion of Plant materials for the Trace Element Determination
    Krystyna Srogi

  6. Commercialization of Research Results of Polish Chemists Originating from Universities - Opurtunities, Limitations, Prospectives
    Jacek Guliński

  7. Isomer Enumeration: from Cayley to Nanotubes
    Jan Cz. Dobrowolski

  8. Tools for Combinatotial Chemistry. Part 4. Solid Phase Asymmetric Synthesis
    Ryszard Łaźny, Aneta Nodzewska, Beata Żabicka

  9. Antileprosy Drugs
    Krystyna Nowak, Piotr Suryło

  10. Detrmination of Trace Elements in the Human Hair
    Krystyna Srogi

  11. Metals Content in Surface Waters of Urbanised Area in the Gdańsk Municipality
    Grażyna Dembska, Marzena Grynkiewicz, Stanisław Wiśniewski, Barbara Aftanas

  12. The Synthesis and Reactivity of Phosphinous Acid-Boranes
    Marek Stankevič, K. Michał Pietrusiewicz

  13. Inhibitors of Microtubule in Cancer Therapy
    Krystyna Dzierzbicka, Aleksander M. Kołodziejczyk

  14. Ammonium Nitrate as a Risk Factor of industrial and Public Safety
    Bogdan Zygmunt, Daniel Buczkowski

  15. Sodium Water Glasses. Part II. Properties and Molecular Composition of their Aqueous Solutions
    Wiesław Koźlak

  16. Microwave-Assisted Extraction (MEA) of Pollutants Control of Environment
    Krystyna Srogi

  17. Determination of the Electric Dipolar Moment of ArH+ Cation
    Marcin Molski

  18. Single-Fluorophore Spectroscopy
    Andrzej Molski

  19. Metal Comlexes with Boroxide Ligands
    Sergiusz Luliński, Janusz Serwatowski

  20. Application of Glycals in the Synthesis of Glycopyranoses and Glycopyranosides
    Beata Liberek

  21. Peptidyl Anthraquinone Conjugates and its Biological Activity
    Magdalena Kukowska, Krystyna Dzierzbicka, Zbigniew Maćkiewicz

  22. Fluorescence Resonance Energy Transfer (FRET) in the Studies of Tetraplex DNA Structures
    Bernard Juskowiak, Elżbieta Gałęzowska, Jan Paczesny

  23. Chemical Functionalization of Carbon Nanotubes
    Michał Bystrzejewski, Thomas Pichler

  24. Chromatography on the Internet
    Barbara Guzowska-Świder

  25. Primary Structure of SALMONELLA SPP. O-antigens
    Jerzy Gajdus, Renata Głośnicka, Janusz Szafranek

  26. Sodium Water Glasses. Part III. Current Knowledge of Water Glasses
    Wiesław Koźlak

  27. Electrochemistry in Environmental Protection
    Emilia Grodzka, Krzysztof Winkler, Zbigniew Koczorowski

  28. Solid-state NMR Spectroscopy as a Tool for Searching of Polymorphism of the Bioorganic Derivatives
    Sławomir Kaźmierski, Marek J. Potrzebowski

  29. Thio(Bisaryloxo) Titanium Complexes-Precatalysts of Ethene Polymerization
    Zofia Janas

  30. 1,1-Diamino-2,2-Dinitroethene (Dadne), a New High Energetic and Low Sensitive Explosive
    Stanisław Cudziło, Zbigniew Chyłek

  31. Combustion Synthesis of Nanomaterials
    Stanisław Cudziło, Mateusz Szala

  32. The role of ionic liquids in palladium catalyzed C-C bond forming reactions - special influence of imidazolium halides.
    Anna M. Trzeciak

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DIHYDROXYACETONE PHOSPHATE in CHEMISTRY and BIOCHEMISTRY

Katarzyna Ślepokura, Tadeusz Lis

Wydział Chemii, Uniwersytet Wrocławski, ul F. Joliot-Curie 14, 50-383 Wrocław


Dihydroxyacetone phosphate (DHAP)-the phosphate ester of a simple sugar, dihydroxyacetone (DHA)- is the crucial biochemical intermediate of great biological importance, which has been well known for many years. The biological function of DHAP and its wide application as a C3 building block in organic synthesis, along with the chemical synthetic methods yielding DHAP and its derivatives, are described. Some most recently determined crystal structures of DHAP, as well as of a newly discovered dimeric form of it, are presented. We hope that the combination of all the information reported with some structural features of DHA, also described here, will lead us to some answers on DHAP mystery.


Wiadomości Chemiczne, 2006, 60, 5.
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SILICOALUMINOPHOSPHATES and their SELECTED APPLICATIONS

Rafał Łużny, Jerzy Walendziewski

Politechnika Wrocławska, Zakład Chemii i Technologii Paliw, ul. Gdańska 7/9, 50-344 Wrocław


At the end of 20-th century B.M. Lok et al. discovered and next patented a new class of solids. They called it silicoaluminophosphates (abbreviation - SAPO) because of the chemical constitution of these molecular sieves. These new materials consist of tetrahedral units of silicon, aluminium and phosphorous oxides arranged in a manner that can be regarded as silicon substitution into hypothetical aluminophosphate (AlPO4) framework. SAPOs are prepared under mild hydrothermal conditions from gel containing precursors of phosphorous, aluminium, silicon oxide and a structure directing template (mostly amines and quaternary ammonium compounds).

Unique properties of SAPO molecular sieves such as possibility of acidity control of solids in a wide range during synthesis and shape selectivity of catalyst based on silicoaluminophosphate aroused interest of scientists, who started research of the SAPO's properties, new applications and new, improved methods of synthesis of these molecular sieves.

In this paper article we have described properties of silicoaluminophosphates molecular sieves, mechanism of Si incorporation into hypothetical AlPO4 framework and have described known classic methods of the SAPO's synthesis presented by Lok et al. as well as improved ("rapid" method, non-aqueous medium, with surfactant and dry gel conversion). At the end we have presented two of many possible applications . hydroisomerization of n-paraffins and synthesis of olefins using "Methanol To Olefin Process".


Wiadomości Chemiczne, 2006, 60, 47.
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METHODS of 90Sr ANALYSIS in EVIRONMENTAL SAMPLES

Jan Solecki

Zakład Radiochemii I Chemii koloidow, Wydział Chemii Uniwersytetu Marii Curie-Skłodowskiej, pl. M.Curie-Skłodowskiej 2, 20-031 Lublin


Application of nuclear reactions for military purposes and technical imperfection of nuclear power plants raised interest in formation of radioactive elements in these processes on one hand and their occurrence in environment on the other. 90Sr, (β-emitter), belongs to isotopes of high radiotoxicity due to its good assimilation by organisms and long half-life time as well as biological half-life. Respective data are presented in Table 1 [1-4].

Because of radiochemical properties of 90Sr, analysis of its concentration is very difficult. The whole process comprises laborious stages: isolation of the isotope from the sample, removing contamination, elimination of the decay product (90Y) and radioactivity measurement.

Many analytical methods have been presented in literature for years. Generally, one can divide them in two groups: fast [6-12] and standard [14-34].

Fast methods, (from several hours to a few days) are mostly applied to .fresh. samples (immediately after radioactive fall-out) containing 89Sr and 91Y beside 90Sr and 90Y. Despite smaller accuracy they can provide information on possible danger. More credible data may be obtained from .old. samples (2-3 years from contamination) by standard methods. The mostly encountered analytical problems are: sample dissolution, removal of calcium and iron ions, removing primary/parental isotopes of radium, thorium, actinium and lead.

Methods for 90Sr-90Y separation (liquid-liquid and solid-liquid extraction) are well known and broadly presented in literature [6-10, 30-34]. Those methods used to determine concentration of radioactive 90Sr in environmental samples. A skilled radioanalyst may modify them according to the needed procedure, which is described in present paper.


Wiadomości Chemiczne, 2006, 60, 75.
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FORMALDEHYDE in AIR-SOURCES, TOXICOLOGY and METHODS of REMOVAL from INDOOR AIR

Irena Jacukowicz-Sobala, Elżbieta Kociołek-Balawejder

Katedra Technologii Chemicznej, Wydział Inżynieryjno-Ekonomiczny, Akademia Ekonomiczna we Wrocławiu, ul Komandorska 118/120, 53-345 Wrocław


Formaldehyde is known to be ubiquitous pollutant in an atmospheric environment. It enters the atmosphere from natural processes such as: biomass combustion, metabolic processes and from direct human sources -fuel combustion (automotive, power plants and waste incinerators) and industrial emissions (occurring during production, use and storage of formaldehyde). Formaldehyde is also formed in photochemical oxidation of methane and other volatile organic compounds including natural and anthropogenic ones, like: alkanes, alkenes, aldehydes and alcohols [6, 16]. Acting as a source of radicals in the atmosphere and precursor of ozone, peroxyacetyl nitrate and nitric acid formation, formaldehyde is an important contributor to photochemical smog in urban air [7, 10, 20, 21].

Although natural direct emissions and secondary production seem to be larger than direct anthropogenic releases, the highest levels of formaldehyde concentrations occur near anthropogenic sources. Concentrations of formaldehyde in clean rural air are usually below 1,5 μg/m3 and about 20 μg/m3 in urban areas [3].

Formaldehyde is a major intermediate product in chemical manufacturing. Its main uses are the production of phenolic, urea, melamine and polyacetals resins, which are widely used as adhesives and binders in wood, textile, pulp and paper industries. Formaldehyde is also used as a preservative, disinfecting and cleaning agent in many products used in daily life. Building, decorating and insulating materials, furniture, wooden floors, carpets and textile garments are significant formaldehyde emissions sources in indoor areas. In addition formaldehyde in homes is released (about 10-30%) from combustion processes (tobacco smoking, fireplaces and furnaces). Due to the widespread distribution of formaldehyde sources in houses, average levels of its concentrations in indoor air are 20-60 μg/m3 and are usually evaluated according to limits of formaldehyde concentration [3, 11, 16, 22].

Formaldehyde even at low exposure levels causes burning sensations in the eyes, nose and throat, and contributes to sick house syndrome. Long-term exposure induces sensitization to formaldehyde which may develop an allergic reaction. Formaldehyde was a suspected carcinogen and an established 2A group in the International Agency for Research on Cancer (IARC) classification system until 2004, when the working group of IARC reclassified it as a human carcinogen (1G) [3, 4].

According to the toxicity and exposure levels of formaldehyde, there is the necessity to take measures to reduce formaldehyde concentrations in indoor air. There are some simple ways of limiting its emission, i.e. buying wood products, furniture and decorating materials with low formaldehyde content, ensuring adequate ventilation, temperature moderation and reduction of humidity levels [22]. The most effective solution is air cleaning which is recently becoming more popular. There are some general methods of air purification like adsorption of formaldehyde on activated carbon or other adsorbents with functional groups reactive to formaldehyde (usually primary and secondary amine groups) [48-65], and an alternative technique-oxidation, including: heterogonous catalytic oxidation with air, photocatalytic degradation and oxidation of formaldehyde using potassium permanganate filters [76-91].


Wiadomości Chemiczne, 2006, 60, 91.
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MICROWAVE DIGESTION of PLANT MATERIALS for the TRACE ELEMENT DETERMINATION

Krystyna Srogi

Instytut Przeróbki Węgla, ul. Zamkowa 1, 41-803 Zabrze


This paper presents a review of microwave heating applications in plant materials. Decomposition of solid samples (plant material) is an important step in combined analytical methods. In most cases, when using highly sensitive measuring methods, such as flame atomic absorption spectrometry (FAAS), graphite furnace AAS, ICPAES, ICP-MS, the sample is measured in an aqueous solution. Combined analytical methods are favoured for multi element analysis of botanical samples at very high speed. Sequential and simultaneous determinations of the elements can be made using the above analytical techniques.

A wide range of microwave digestion procedures for plant tissues has been used such as dry ashing, open vessel digestion, microwave dissolution and acid bomb digestion, etc. Although these procedures generally show both good accuracy and precision, some of them are rather time-consuming. Several factors should be considered while preparing samples for analyses. These may include the level of contamination, having homogenous samples, reproducibility and completeness of the digestion, suitability for the analysis technique, time needed for sample preparation and economic aspects, etc.


Wiadomości Chemiczne, 2006, 60, 121.
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COMMERCIALIZATION of RESEARCH RESULTS of POLISH CHEMISTS ORIGINATING from UNIVERSITIES - OPURTUNITIES, LIMITATIONS, PROSPECTIVES

Jacek Guliński

Wydział Chemii UAM, Poznań, Poznański Park Naukowo-Techniczny Fundacji UAM, ul. Rubież 46, 61-612 Poznań


The role of university research in chemistry in the regional, national and international innovation and technology transfer as well as critical overview of the opportunities and limitations of chemistry research commercialization are presented and discussed.


Wiadomości Chemiczne, 2006, 60, 149.
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ISOMER ENUMERATION: FROM CAYLEY TO NANOTUBES

Jan Cz. Dobrowolski

Instytut Chemii Przemysłowej, ul. Rydygiera 8, 01-793 Warszawa
Narodowy Instytut Zdrowia Publicznego, ul. Chełmska 30/34, 00-725 Warszawa


Chemical graph theory is a dynamically developing area of mathematical chemistry which is taught at Chemistry Departments of Polish Universities only seldomly. Especially, molecular graph enumeration, which is one of the oldest branch of chemical graph theory, begun by English mathematician Arthur Cayley(s work On the Mathematical Theory of Isomers published in 1874, will always support and stimulate progress of chemistry. In this review, the most important theorem for graph enumeration, known as Pólya Hauptsatz, proven in 1930s by Hungarian and American mathematician George Pólya (1887(1985) is only illustrated. The review remainds early Henze i Blair results of alkanes enumerations as well as quite modern Robinson, Harary, and Balaban enumeration of chiral alkanes. Selected results found for benzenoid hydrocarbons are presented and through the famous Euler polyhedron rule a connection with enumeration of fullerenes and nanotubes is shown.

Keywords: Isomer, enumeration, fullerenes, graph theory


Wiadomości Chemiczne, 2006, 60, 171.
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TOOLS for COMBINATOTIAL CHEMISTRY. PART 4. SOLID PHASE ASYMMETRIC SYNTHESIS

Ryszard Łaźny, Aneta Nodzewska, Beata Żabicka

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


Solid Phase Asymmetric Synthesis (SPOS) is a recently introduced term embracing all methods of asymmetric synthesis involving use of solid supported substrates and reagents. This review presents basic definitions of asymmetric synthesis and currently used concepts for enatioselective and diastereoselective transformations involving supported synthesis. The concepts of chiral auxiliary, chiral catalyst and chiral reagent are illustrated with selected but fairly comprehensive overview of methods published till January 2005. In particular use of chiral auxiliaries such as oxazolidine derivatives, amines, hydrazines, sulfoxides, sulfinyl amides, sulfoxy imines, carbohydrates and alcohols is covered. Applications of immobilized chiral catalysts to synthesis of carbon-carbon bonds, carbon-hydrogen bonds, carbon-heteroatom bonds and in phase-transfer catalysis is presented with selected reactions due to huge volume of literature in this field. Moreover applications of chiral catalysts and chiral reagents in reactions of immobilized substrates and use of chiral immobilized reagents is also reviewed. The literature review shows that the most popular methods of supported asymmetric synthesis are the alkylation of enolates, aldol reactions, Grignard reactions, cycloadditions, reduction of ketones, epoxidations, olefin dihydroxylation, and phase-transfer catalyzed reactions. There are numerous applications of immobilized chiral catalysts and a substantial number of applications of immobilized chiral auxiliaries. On the other hand there are only scarce reports of applications of chiral reagents and chiral catalysts to the reactions of achiral immobilized substrates.

Keywords: Solid-phase synthesis, asymmetric synthesis, polymer supported reaction, combinatorial chemistry, organic synthesis.


Wiadomości Chemiczne, 2006, 60, 191.
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ANTILEPROSY DRUGS

Krystyna Nowak, Piotr Suryło*

Instytut Chemii i Technologii Organicznej, Politechnika Krakowska
*Instytut Chemii i Technologii Nieorganicznej, Politechnika Krakowska, ul. Warszawska 24, 31-155 Kraków


ABSTRACT Leprosy is a chronic infectious disease, that is caused by a bacillus of Mycobacterium leprae. It was considered to be an incurable disease for ages. Nowadays leprosy is a vanishing disease although you can meet it principally in the tropical zone countries [3-8]. Since times immemorial, the natural origin preparations had been involved under the leprosy treatment. One of them was chaulmoogra, the oil isolated from seeds of: Hydnocarpus kurzii, the gorli tree - Oncoba echinata and Carpotroche brasiliensis plant [14]. The main components of the chaulmoogra oil are triglicerides of hydnocarpic acid (1), chaulmoogric acid (2) as well as gorlic (3) [16, 18, 19]. In 1921 year , ethyl esters of named above acids were applied successfully in the leprosy treatment [23]. Other natural origin components also reveal leprostatic effectiveness. There are derivatives of boswelin acid 4, 5 which have been found in the Boswelia serrata plant [19, 29, 30].

The first and effectively applied antileprosy drug up today, occured Dapsone (6), which was introduced in the leprosy therapy in 1946 year [12]. This medicine has appeared comparatively little toxic, inexpensive and effective at all forms of leprosy [12, 32, 33].

A great number of Dapsone (6) derivatives have been received lately. Most of them have been introduced to the therapy of leprosy and other bacterial diseases (Table 3).

The next group of derivatives of Dapsone (6) composes the ones, with substitutions in the phenyl ring 15. Such combinations are received in result of a multistage synthesis (Scheme 3).

There have been still lasting experiments above receiving new active sulfones in relation to bacillus of Mycobacterium leprae [53]. Among sulfones not being derivatives of Dapsone (6) Promizole (19) has been found and applied in the leprosy therapy [31]. The method of its synthesis has been introduced on Scheme 4.

Except sulfones, sulfonamides are also employed in the leprosy therapy, in spite that theirs activity in relation to Mycobacterium leprae is small [3, 32, 55, 56]. After all, Sulfomethoxazole (22) gives good therapeutic results 22 in connection with Trimethoprim (24). These connections are being utilised in a multidrug, antileprosy therapy [57]. There are a few methods of receiving of Sulfomethoxazole (22) (Schema 5) and Trimethoprim (24) (Schemes 6-8) [58-68].

The derivatives of Trimethoprim (24), Brodimoprim (35) and Epiroprim (36) have been received by the Swiss. Hoffmann-La-Roche Ltd Company and they are likely to be used in the multidrug antileprosy therapy [69-74].

It has been taken an advantage in the leprosy treatment of using derivatives of thiocarbamide - Tiambutazyne (37) and Thiocarlide (38). However the need to engage them in large doses is the basic defect of these medicines [55, 75]. Tiambutozyne (37) has being received as a result of the p-amine-N,N-dimethylaniline reaction witch p-propoxyphenylisothiocyanate (Scheme 9), however Thiocarlide (38) synthesis depends on the 4-(3-methylbutoxy)aniline reaction with carbon disuflide (Scheme 10) [76-77].

There are also some amides e.g. Ethionamide (40a), Prothionamide (40b) as well as Pyrazinamide (51) which produce a good antileprosy influence.

These medicines have found the application mainly in the tuberculosis treatment, though in the antileprosy therapy either [24]. The method of synthesis of Ethionamide (40a) and Prothionamide (40b) has been presented on Scheme 11.

Still, the experiments on new effective working antileprosy combinations have been carrying out. According to results, good antileprous proprieties have characterized the derivatives of thiazolidine (42) and thiocarbamide (39) [77, 79, 84]. Searching for new antileprosy medicines have still been led in the sulfons and sulfonamides groups [85-86]. A number of new medicines has entered the therapy of leprosy at present and among others there are chiefly ansamycin, chinolones and ketholides antibiotics. However Dapsone has still been fulfilling the most important part 6, which for over of 60 years continually has been determining the basic antileprosy medicine.

Keywords: antileprosy drug, lepra, Mycobacterium leprae, Dapson


Wiadomości Chemiczne, 2006, 60, 257.
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DETRMINATION OF TRACE ELEMENTS IN THE HUMAN HAIR

Krystyna Srogi

Instytut Chemicznej Przeróbki Węgla, ul Zamkowa 1, 41-803 Zabrze


The analysis of human hairs is useful in monitoring the level of certain trace elements and drugs in the body. The specific problems of sampling and sample preparation are presented. Also, the application and relevance of hair analysis is illustrated and discussed on the basic of examples from clinical and environmental chemistry. The paper presents an updated review of the techniques for hair analysis, including spectrometry and more sophisticated methodologies adopted for result confirmation and/or for research purposes.

Keywords: biomonitoring, human hair, trace elements analysis, preparation of hair samples, FAAS, ETAAS, ICP-AES, ICP-MS, FI-CV-AAS


Wiadomości Chemiczne, 2006, 60, 279.
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METALS CONTENT IN SURFACE WATERS OF URBANISED AREA IN THE GDAŃSK MUNICIPALITY

Grażyna Dembska, Marzena Grynkiewicz, Stanisław Wiśniewski, Barbara Aftanas

Instytut Morski w Gdańsku, Zakład Ochrony Środowiska, ul. Długi Targ 41/42, 80-830 Gdańsk


The objective of the work was to assess the degree of pollution of running surface waters in the Gdańsk Municipality by heavy metals, and to attempt an evaluation of the impact of these waters on heavy metal loads in the Gulf of Gdańsk waters.

Investigations were carried out at 22 measurement stations, located on 14 flows (5 rivers, 5 streams, 2 rain water collectors and 2 channels), which either directly ("Kołobrzeska" collector and its tributary rain water collector from Brzeźno, and Jelitkowski Stream and its tributary Rynarzewski Stream) or indirectly (through flows discharging into the Martwa Vistula) discharge into the Gulf. Measurements were carried out once every month in the period April-October 2004. Water samples were tested for content of the following elements: Pb, Cu, Zn, Ni, Cd, Cr, As, Hg, Fe, Mn, Ca, Mg, B, Ba, Sr, Ag, Al, V, Co. Mercury was determined by atomic absorption, cold vapour technique. All the other elements were determined by emission spectrometry with inductive excited plasma

The work included also an assessment of the quality of investigated surface waters (from the point of view of heavy metal content) in accordance with regulations in force, and chemical-metric analysis of obtained results.

The carried out investigations of heavy metal content in open water flows in the Gdańsk Municipality are of practical and research value especially for the investigated area. It was found that quality class of the flows depended mainly on the concentrations of: Hg, Fe, Mn, Ca, Mg and Al, and the most often occurring elements in the Class V waters were Fe and Al. Therefore, extending monitoring of open water flows in the Gdańsk Municipality to include also Ca, Mg, Fe, Mn, Al should be seriously considered, since their concentrations, as has been shown in the present work, may have a significant influence on the quality of these waters.

Keywords: metals, surface waters, urbanised area, emission spectrometry


Wiadomości Chemiczne, 2006, 60, 301.
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THE SYNTHESIS AND REACTIVITY OF PHOSPHINOUS ACID-BORANES

Marek Stankevič, K. Michał Pietrusiewicz

Zakład Chemii Organicznej, Wydział Chemii, Uniwersytet Marii Curie-Skłodowskiej, ul. Gliniana 33, 20-614 Lublin


Borane complexes of trivalent phosphorus compounds are versatile synthetic intermediates which are especially useful in the elaboration of phosphine structures and in the preparation of chiral phosphine ligands. Despite the synthetic importance and wide use of derivatives of phosphinous acid-boranes such as their esters (phosphinite-boranes), or acid chlorides (sec-chlorophosphine-boranes), the parent phosphinous acid-boranes have until very recently remained practically unexplored. New developments of convenient and general methods of synthesis of phosphinous acid-boranes from secondary phosphine oxides or from phosphinic chlorides have made them now readily accessible as a novel class of organophosphorus reagents. When nonsymmetrically substituted phosphinous acid-boranes bear a center of chirality at P and are configurationally stable. Phosphinous acid-boranes possess a rich reactivity pattern offering many useful synthetic transformations through the reactions at their P, O, or B, reactivity centers. A large variety of other organophosphorus compounds such as phosphinite-boranes, boranatophosphinous anhydrides and mixed anhydrides, secondary phosphine-boranes, tertiary phosphine-boranes, secondary phosphine oxides, phosphinic halides, and oxaphosphaborolidines, can all be readily derived from phosphinous acid-boranes in a single synthetic operation.

Keywords: phosphine-boranes, sec-phosphine-boranes, sec-phosphine oxides, phosphinic halides, phosphinite-boranes


Wiadomości Chemiczne, 2006, 60, 323.
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INHIBITORS OF MICROTUBULE IN CANCER THERAPY

Krystyna Dzierzbicka, Aleksander M. Kołodziejczyk

Katedra Chemii Organicznej, Wydział Chemiczny, Politechnika Gdańska, ul. G. Narutowicza 11/12, 80-952 Gdańsk


Microtubule targeting drugs being in the late preclinical or early clinical development are described in this article. New semisynthetic paclitaxel analogues, natural compounds of diverse structure such as epothilones, combretastatins, colchinoids or dolastatins (Fig. 2-4) and synthetic compounds of low molecular weight such as heterocombretastatins, sulfonamides, phenstatins, indoles and quinolones (Fig. 5 and 6) belong to this category of anticancer medicines [7]. Microtubules are hollow tubes consisting of ?- and ?-tubulin heterodimer proteins that polymerize parallelly to a cylindrical axis [75]. The targeting of microtubules is an important mechanism in cancer chemotherapy for such drugs as the vinca alkaloids (vincristine 1, vinblastine 1a), podophilotoxin, their semisynthetic analogues and taxanes (paclitaxel 2, docetaxel 3) (Fig. 1) known of their great usefulness in the anticancer therapy [7,75]. These agents may stabilize microtubules, as the taxanes do, or destabilize them, as it is in the case of the vinca alkaloids. Today, more than 30 compounds targeting tubulin, either stabilizing or destabilizing microtubule dynamics, are in late preclinical or early clinical development. Despite of more than 30 years after the discovery of paclitaxel microtubule inhibitors they are still of the topic of interest of all over the world.

In the end of 1990 and up to 2005 year survey articles on the microtubule inhibitors were published [7-12]. We expect now that the paper which presents last results study may be useful.

Keywords: Inhibitors of microtubule, tubulin, taxol, combretastatin, antitumor activity, antimitotic activity


Wiadomości Chemiczne, 2006, 60, 345.
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AMMONIUM NITRATE AS A RISK FACTOR OF INDUSTRIAL AND PUBLIC SAFETY

Bogdan Zygmunt1, Daniel Buczkowski2

1Wydział Mechatroniki Wojskowej Akademii Technicznej, ul. Kalińskiego 2, 00-908 Warszawa
2Instytut Przemysłu Organicznego, ul Annopol 6, 03-236 Warszawa


Ammonium nitrate (AN) is one of the most popular synthetic chemicals in the world, produced in quantity of a few dozen millions tons every year. The main application of AN is as a nitrogen containing fertilizer in agriculture. The second large use, but in a much minor scale, is as an essential ingredient for manufacturing AN based explosive for mining industry. In both application AN is used in a granular or prilled form. Granules/prills of commercial AN of dimension from 1 mm to 5 mm reveal much better exploitation properties than other form (grains, crystals). Granulated/prilled AN characterizes excellent flow ability what make easier final manufacturing operations and usage. Granulated/prilled form of AN also posses a relatively higher resistance to caking - the main disadvantage of many fertilizers.

The history of large scale production of AN started in the beginning of XX century. Till those times, AN was regarded as a moderate oxidizer, without explosive features as a pure compound. Huge industrial catastrophes in Germany in 1921 caused by unexpected explosions of large amount of AN were the reason to change radically the opinion concerning the safety of the chemical. Massive explosions of AN still take place nowadays during production processes, transportation and storage, even in highly technologically advanced countries (USA, France).

Since the last few decades AN in a form of porous prills/granules is used for manufacturing the most popular explosive in mining industry. Porous AN saturated with 5-6 % of fuel oil is relatively powerful, safe in handling and the cheapest tool for crushing mineral deposits. The explosive is called ANFO what origins from the acronym of ingredients. Explosive properties of AN and its mixtures are well known by world-wide net of terrorist groups. In the last dozen years about hundred terrorist attacks have been performed using large weight bombs consist mainly of easy available mining grade or fertilizer AN. The pattern to prepare bomb attacks is the criminal case which took place in Oklahoma City (USA, 1995), where federal skyscraper was ruined by explosion of 2 tons AN charge killing 170 persons and wounding hundreds people.

The scientific and technological problem is to produce AN of two grades. First, as a fertilizer with no limitation in purchasing, should characterize full resistance to explosion and without potential ability to make explosive mixture with other additives. The second, as a raw material for manufacturing ANFO, it should be available only for professionals which posses appropriate permission and because such a product itself is an explosive material with all limitations in transportation, storage and handling.

In the paper the review of huge industrial catastrophes as well as terrorist attacks caused by explosion of AN were done. The physical properties of AN used as a fertilizer in agriculture and as an ingredient for manufacturing of mining explosives were described.

Keywords: ammonium nitrate, ANFO, industrial explosion, bomb attack


Wiadomości Chemiczne, 2006, 60, 365.
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SODIUM WATER GLASSES. PART II. PROPERTIES AND MOLECULAR COMPOSITION OF THEIR AQUEOUS SOLUTIONS

Wiesław Koźlak

Zakład Podstaw Chemii Wdziału Budownictwa, Mechaniki i Petrochemii Politechniki Warszawskiej, ul Łukasiewicza 17, 09-400 Płock


General properties of aqueous solutions of sodium silicates as a function of most important parameters, such as: silicate modulus, concentration, temperature, pH, ageing time, presence of electrolytes and technology of their preparation, are presented in this work. At the same time the proposition of treating these systems as mixtures of silicic acid and silicates, buffer mixtures and inorganic colloids, was given.

The history of studies of the properties and molecular composition of water glasses solutions, both in Poland and abroad, was included in this work.

Because of the complexity of the discussed systems, arising from the diverse levels of condensation of both silicic acids and silicate ions, a review of most frequently used and most useful methods and experimental techniques for the evaluation of molecular composition of aqueous solutions of silicates, was conducted.

Such diversity of experimental techniques is a consequence of the fact that water glasses and systems in which they occur, having such versatile applications in many branches of the economy, still do not have complete and uniform literature study. It is the reason why in this article general conclusions based on experimental results received with the discussed methods are presented.

Keywords:sodium water glasses, silicate aqueous solutions, properties, molecular composition, analytical methods, process of condensation


Wiadomości Chemiczne, 2006, 60, 379.
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MICROWAVE-ASSISTED EXTRACTION (MEA) OF POLLUTANTS CONTROL OF ENVIRONMENT

Krystyna Srogi

Zakład Chemicznej Przeróbki Węgla, ul. Zamkowa 1, 41-803 Zabrze


The use of microwave energy in sample treatments has attracted growing interest in the past few years. Initially, it was applied to the mineralization of samples. In recent years, numerous applications have reported the use of microwaves for assisting the extraction of organic compounds and organometallic compounds form various environmental matrices. In fact, the use of microwave energy to aid organic extraction was first achieved using conventional household systems in the late 1980s. Thus, in the past few years, numerous compounds have been extracted by microwave-assisted extraction (MAE) from several matrices, with special emphasis on environmental applications.

Microwave-assisted extraction (MAE) is a process of using microwave energy to heat solvents in contact with a sample in order to partition analytes from the sample matrix into the solvent. The ability to rapidly heat the sample solvent mixture is inherent to MAE and the main advantage of this technique. By using closed vessels the extraction can be performed at elevated temperatures accelerating the mass transfer of target compounds from the sample matrix. A typical extraction procedure takes 15-30 min and uses small solvent volumes in the range of 10-30 ml. These volumes are about 10 times smaller than volumes used by conventional extraction techniques. In addition, sample throughput is increased as several samples can be extracted simultaneously. In most cases recoveries of analytes and reproducibility are improved compared to conventional techniques, as shown in several applications. This review gives a brief theoretical background of microwave heating and the basic principles of using microwave energy for extraction. It also attempts to summarize all studies performed on closed-vessel MAE until now. The influences of parameters such as solvent choice, solvent volume, temperature, time and matrix characteristics (including water content) are discussed.

This article reviews the application of microwave energy to the extraction of organic and organometallic compounds from environmental samples, namely: polychlorinated biphenyls (PCBs), pesticide, phenol, polycyclic aromatic hydrocarbons (PAHs) and dioxins.

Keywords: microwave-assisted extraction (MAE), sample of environment, PCB, PAH, dioxins


Wiadomości Chemiczne, 2006, 60, 397.
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DETERMINATION OF THE ELECTRIC DIPOLAR MOMENT OF ARH+ CATION

Marcin Molski

Zakład Chemii Teoretycznej, Wydział Chemii, Uniwersytet im. A. Mickiewicza w Poznaniu, ul. Grunwaldzka 6, 60-780 Poznań


Determination of the electric dipolar moment of a molecule is one of the most important procedures applied to characterize the molecule spectral activity, type of the chemical bonds between atoms forming the molecule and its geometry [1, 2]. Electric dipolar moment can be determined by making use of the Stark or Zeeman effects, quantum-mechanical ab initio calculations or from highly resolved MW and IR rotation-vibrational spectra using spectroscopic methods. Each of the methods mentioned has advantages and disadvantages. For example, the Stark method cannot be applied to molecular ions as under external electric field they are accelerated towards the wall of the discharge tube. In 1955 Townes et al. [5], developed the method of determination of the dipolar moment using the Zeeman effect. This approach has been generalized in 1987 by Laughlin et al. [6], and applied to ArH+ cation. They obtained the values: 1.4(4) D [6], 1.59(40) D [7] and 3.0(6) D [8], which seriously differed from the ab initio result 2.2(1) D provided by Rosmus in 1979 [10]. The additional ab initio calculations performed by Pyykkö et al. [11], and then by Geertsen and Scuseria [12] in 1989, confirmed the correctness of the result obtained earlier by Rosmus. In such circumstances only the application of a third independent method could provide a correct value of the electric dipolar moment of ArH+. Following this suggestion, Molski [26] in 2001 applied the spectroscopic method to evaluate dipolar moment of ArH+ from highly resolved MW and IR spectra including pure rotational and vibration-rotational lines. The result obtained 2.12(55) D confirmed that ab initio calculations provided a reliable value of the dipolar moment of ArH+, whereas the experimental values obtained by Laughlin et al., were less accurate. The supplementary calculations performed for KrH+ [27] and HeH+ [29] indicate that the method of Laughlin et al. [6, 7, 8] does not produce reliable values of the electric dipolar moment for diatomic ions, whereas for polyatomic molecules this method is reliable [15, 16].

Keywords: electric dipolar moment, Lande factor, diatomic molecules, Stark effect, Zeeman effect, IR and MW spectra


Wiadomości Chemiczne, 2006, 60, 423.
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Single-Fluorophore Spectroscopy

Andrzej Molski

Pracownia Dynamiki Procesów Fizykochemicznych, Wydział Chemii, Uniwersytet im. A. Mickiewicza, ul. Grunwaldzka 6, 60-780 Poznań


This article is an introduction to single-fluorophore spectroscopy (SFS). The basic phenomenon seen in SFS is fluctuations of fluorescence intensity of single nano-objects (dyes, biopolymers, nano-crystals, aggregates). These fluctuations are called fluorescence blinking and carry information on dynamics of the fluorophore and its surroundings. In the simplest case the fluorescence trajectory jumps between two levels, a bright one (on) and a dark one (off). In this article on-off fluorescence blinking associated with triplet states of organic dyes, excitation of quantum dots, and enzymatic reactions at room temperatures are reviewed. The cited literature indicates current problems and may serve as an introduction to modeling and simulations of SFS.

Keywords: single-fluorophore spectroscopy, fluorescence blinking, organic dyes, quantum dots, single-enzyme fluorescence


Wiadomości Chemiczne, 2006, 60, 449.
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METAL COMLEXES WITH BOROXIDE LIGANDS

Sergiusz Luliński, Janusz Serwatowski

Politechnika Warszawska, Wydział Chemiczny, ul. Noakowskiego 3, 00-664 Warszawa


The review deals with metal complexes bearing various types of boroxide ligands. It is divided into several chapters including synthesis, structural and spectroscopic (NMR) characterization followed by reactivity and catalytic properties of some novel compounds. Metal complexes with boroxide ligands can generally be defined as derivatives of hydroxydiorganoboranes R2BOH or dihydroxyorganoboranes RB(OH)2, where one or two hydrogen atoms are replaced with a metal. A few complexes with a closely related R2B2O32- ligand derived from triorganoboroxin [RBO]3 have also been included. Boroxide ligands may be regarded as electrondefficient analogues of alkoxide ligands, due to specific electronic properties of a trivalent boron atom, which is able to interact by means of its 2p orbital with a lone electron pair of an adjacent oxygen atom. As a result of this so-called back-bonding, the B-O bond order is increased, whereas the π-donor properties of oxygen are reduced. Accordingly, a metaloxygen bond is weakened. Another important point is that boroxides are sterically less crowding than bulky aryloxide ligands having comparable electronic properties. Hence, an increased reactivity of such complexes is expected, especially as catalysts or initiators in various polymerization processes.

Keywords: boroxide ligands, metal alkoxides, hydroxyorganoboranes, polymerization


Wiadomości Chemiczne, 2006, 60, 467.
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APPLICATION OF GLYCALS IN THE SYNTHESIS OF GLYCOPYRANOSES AND GLYCOPYRANOSIDES

Beata Liberek

Wydział Chemii, Uniwersytet Gdański, ul. J. Sobieskiego 18, 80-952 Gdańsk


Glycals, systematically named 1,5-(or 1,4-)anhydro-2-deoxy-hex-(or -pent-)1-enitols [1], posses a double bond between C-1 and C-2 carbon atoms of a pyranose or furanose ring and are one of the most useful substrates in carbohydrate chemistry. Presence of the double bond in glycals makes them possible to undergo variety of the reactions, including different additions, hydroxylation, epoxydation, cycloadditions, allylic rearrangement and many others. The majority of these reactions were described in 1960s and 1980s by Ferrier [5, 6]. However, applications of glycals, especially as glycosyl donors, have been systematically developed and new methodologies have been employed in the last decade. This paper presents useful procedures, mainly resulting in the stereoselective synthesis of a glycoside bond.

The presented applications of glycals are divided into following groups: addition of water [7-11], synthesis of 2-deoxyglycosides [12-77], synthesis of 2-amino-2-deoxyglycosides [78-107], synthesis of glycosides possessing 2-hydroxy group [108-120], Ferrier rearrangement [121-146], formation of the α,β-unsaturated aldehydes [147-158], cyclopropanation [159-168] and cycloaddition [169-181].

Keywords: glycal, electrophilic addition, 2-deoxyglycoside, 2-amino-2-deoxyglycoside, epoxydation, Ferrier rearrangement, a,b-unsaturated aldehyde, cyclopropanation, cycloaddition


Wiadomości Chemiczne, 2006, 60, 487.
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PEPTIDYL ANTHRAQUINONE CONJUGATES AND ITS BIOLOGICAL ACTIVITY

Magdalena Kukowska1, Krystyna Dzierzbicka2, Zbigniew Maćkiewicz1

1Zakład Chemii Polipeptydów, Wydział Chemii, Uniwersytet Gdański, ul. Sobieskiego 18/19, 80-952 Gdańsk
2Katedra Chemii Organicznej, Wydział Chemiczny, Politechnika Gdańska, ul. G. Narutowicza 11/12, 80-952 Gdańsk


This article concerns methods of synthesis and biological activity of peptidyl anthraquinones. The group of these components have a big influence on a present medicine. Among components, that were presented in this paper, many number of them show antineoplastic activity. These peptidyl anthraquinones demonstrate special mechanism of action, stabilizing cleavable complex consisting of topoisomerase, convalently attached to DNA and stop correct replication and transcription. Using of topoisomerases inhibitors (11a,c,d, 73l,m) (Figure 2 and Scheme 9) in therapy of cancer have promising results [18, 26-28]. Anthraquinones analogues with peptidyl chain (78a-h) (Scheme 10) including KCR motif very important in AP-1 protein binding to DNA. This group of compounds can be used as potential transcription factor inhibitors, because they show DNA intercalative binding and recognize specific sequences of DNA binding domains [48-54]. Synthetic GnRH analogues including rings of anthraquinone (69a,b) (Scheme 8) present interesting drugs using in reproductive diseases, for instance prostate, ovarian and breast cancer. The mechanism of action of GnRH analogues count on binding to GnRH receptors, which we can find in cells of reproductive organs [45, 46]. MMP-9 activity can be exploited to activate prodrugs and be a target the tumour cells in BM. Cleavage of the prodrugs (66, 67a,b) (Figure 3) with MMP-9 resulsts in the liberation of the active form of drug which can be an inhibitor of topoisomerase. Tripeptide derivatives of anthraquinone (22, 33, 40) (Scheme 2, Scheme 3) show the activity as histochemical reagents for detection of TTP I activity [38-44]. Peptidyl anthraquinones can be also used for protein purification and labeled peptides as biochemical probes for DNA detection [18].

Keywords: peptidyl anthraquinone conjugates, synthesis, biological activity


Wiadomości Chemiczne, 2006, 60, 523.
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FLUORESCENCE RESONANCE ENERGY TRANSFER (FRET) IN THE STUDIES OF TETRAPLEX DNA STRUCTURES

Bernard Juskowiak, Elżbieta Gałęzowska, Jan Paczesny

Wydział Chemii, Uniwersytet im. A. Mickiewicza, ul. Grunwaldzka 6, 60-780 Poznań


DNA sequences with stretches of multiple guanines can form four-stranded tetraplex DNA structures called guanine-quadruplexes or G4 DNA. They contain stacked arrays of planar guanine quartets linked by connecting loops (Fig. 1, Fig. 2). Evidence supports the occurrence of quadruplexes in the cell nucleus and a number of biological functions have been attributed to quadruplexes. In eukaryotic systems guanine-rich sequences are positioned at the ends of chromosomes and are called telomeric DNA. The study of telomeric DNA has acquired importance through the discovery of the relationship between telomerase activity in most cancer cells and telomere folding into tetraplex structure. Coordination of certain metal cations stabilizes G-quadruplex as do some promising small organic molecules, which are regarded as potential anticancer drugs. Among many techniques employed to explore properties of G-quadruplexes, fluorescence resonance energy transfer (FRET) has been recognized as a powerful tool to explore tetraplex formation due to extreme sensitivity and the distance dependency of the FRET process.

This review shows how FRET contributes to G-quadruplex research and focuses on the FRET application, describing briefly also the underlying principles. Information about molecular structure, binding events, and motion are considered to be potentially available from FRET measurements. In a typical FRET experiment a guanine-rich oligonucleotide labeled with proper fluorophores (FRET donor and acceptor) undergoes structural transformations (folding or unfolding), which are monitored by spectral changes in the fluorescence spectra of FRET partners. We tried to summarize the current developments in the field of the various applications of FRET measurements for the fundamental structural and kinetic investigations of G-quadruplexes and their complexes with metal cations and organic ligands. Fundamental applications include studies of quadruplex unfolding kinetics with the use of complementary DNA or PNA (Peptide Nucleic Acid) strands as a duplex trap or determination of thermodynamic parameters. Practical applications are illustrated by the FRET-based selection of quadruplex-binding ligands, construction of the quadruplex-based nanomotor, design of molecular probes for protein recognition, and development of sensors for the detection of potassium ions in aqueous media.

The presented examples of FRET studies showed that FRET is particularly useful in structural studies of oligonucleotides capable of folding into tetraplex structure.

Keywords: Fluorescence; Fluorescence Energy Transfer (FRET); G-quadruplex; Proteins; Quadruplex-binding ligands; Telomeric DNA; Tetraplex DNA structure; Thrombin Binding Aptamer (TBA)


Wiadomości Chemiczne, 2006, 60, 547.
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CHEMICAL FUNCTIONALIZATION OF CARBON NANOTUBES

Michał Bystrzejewski1,2, Thomas Pichler2

1Pracownia Fizykochemii Nanomateriałów, Wydział Chemii, Uniwersytet Warszawski, ul. Pasteura 1, 02- 093 Warszawa
2 IFW Leibniz Institute for Solid State and Materials Research Dresden, Helmholtzstr. 20, 01069 Dresden, Germany


The discovery of carbon nanotubes (CNTs) and the recognition of their exceptional properties have generated a great deal of interest. The possible applications arise from the remarkable properties of CNTs such as the highest Young's modulus, highest thermal conductivity, ballistic electron transport, and field emission resulting from high aspect ratio.

The functionalization of carbon nanotubes has become a very actively discussed topic because the CNTs modification is believed to open the road towards real nanotechnology applications. This review with 266 references describes the results on covalent and noncovalent chemical functionalization of carbon nanotubes and related nanostructures. Physical and chemical properties as well as possible applications of functionalized CNTs are also presented.

Keywords: nanomaterials, carbon nanotubes, carbon nanostructures, functionalization


Wiadomości Chemiczne, 2006, 60, 569.
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CHROMATOGRAPHY ON THE INTERNET

Barbara Guzowska-Świder

Zakład Informatyki Chemicznej, Wydział Chemiczny, Politechnika Rzeszowska,
Al. Powstańców Warszawy 6, 35-959 Rzeszów


The paper presents a part of an Internet guide on analytical chemistry, relating to chromatography. The most valuable Web pages for chromatographists and for chromatography education are briefly described. The guide is a Web page implemented in HTML.

Keywords: analytical chemistry, chromatography, Internet, virtual education


Wiadomości Chemiczne, 2006, 60, 609.
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PRIMARY STRUCTURE OF SALMONELLA SPP. O-ANTIGENS

Jerzy Gajdus1, Renata Głośnicka2, Janusz Szafranek1

1 Wydział Chemii, Uniwersytet Gdański, ul. Sobieskiego 18, 80-952 Gdańsk
2 Katedra Mikrobiologii, Akademia Medyczna, ul. Do Studzienki 38, 80-227 Gdańsk


Salmonella spp. are pathogenic Gram-negative bacteria that belong to Enterobacteriaceae family with lipopolysaccharide (LPS) as a constituent of cell wall. This is an integral component of the outer membrane of the wall. Salmonella smooth (S) forms produce LPS, which is composed of three parts, chemically bonded together viz. polysaccharide O-antigen, oligosaccharide core region and lipid A [103]. Antigens O (O-PS) together with H flagella antigens are the foundation of serological classification of these bacteria. O-chain, which is built with up to 50 oligosaccharide repeating units, is one of the products of mild acidic hydrolysis of LPS. Due to the fact that polysaccharide antigens are the sites of specific antibody complexing, any difference in primary and secondary structures of O-antigens reflect serological specificity of bacteria. Taking this fact into consideration, we can distinguish about 2541 Salmonella serotypes with O and H antigenic formulas defined [4]. In this review we present 55 chemical structures of O-antigenic repeating units of Salmonella strains (Tab. 3) including their heterogeneity structures [54, 74, 75, 99]. The structures can have 22 different monosaccharide residues usually in 3 to 6 sugar repeating units. We describe here selected chemical and spectroscopic (MS, NMR) methods for primary structure examination of these bacterial O-PS. Enzymatic and immunochemical methods are also described. Cross-reactions of Salmonella spp. with any other bacteria [16, 17] or blood group A, B, 0 antigens [27, 51, 123] are explained on the molecular level.

Thus, structural assignments of somatic antigens of Salmonella spp. allow us to understand the molecular level of the classification system of these bacteria.

Keywords: O-antigens, Salmonella, primary structure, spectroscopic methods (MS, NMR)


Wiadomości Chemiczne, 2006, 60, 621.
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SODIUM WATER GLASSES. PART III. CURRENT KNOWLEDGE OF WATER GLASSES

Wiesław Koźlak

Zakład Podstaw Chemii Wydziału Budownictwa, Mechaniki i Petrochemii Politechniki Warszawskiej,
ul. Łukasiewicza 17, 09 - 400 Płock


Basing on the review of the latest literature references it can be concluded that despite diverse interests among researchers in both the theoretical and experimental aspects, the most important objective is the evaluation of the structure of water glasses solutions.

It should be expected that the agreement on the unequivocal view on the molecular composition of water glasses or systems containing these substances will bring closer the explanation of the mechanism of their action in most of their applications and also will show new possibilities in this area. Presented material shows that the area of potential application of water glasses expands constantly.

In the field of research on the properties and structure of silicate solutions, most authors concentrate on the issues of condensation (gelation) processes of silicic acid and its ions as a function of various parameters, such as: Mk, pH, ageing time, temperature, type and properties of the solvent (including organic solvents), influence of electrolytes - both cations and anions.

Research is dominated by spectroscopic methods, such as 29SiNMR, IR, but new methods, which haven't been used before, like electrochemical and thermochemical techniques are being introduced.

Keywords: water glass, silicate solutions, properties, molecular composition, applications, preparation.


Wiadomości Chemiczne, 2006, 60, 655.
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ELECTROCHEMISTRY IN ENVIRONMENTAL PROTECTION

Emilia Grodzka, Krzysztof Winkler, Zbigniew Koczorowski

Instytut Chemii, Uniwersytet w Białymstoku, ul. Hurtowa 1, 15-399 Białystok


For decades electrochemical technology has contributed successfully to environmental protection. Electroanalytical techniques have been frequently used in monitoring the changes of environment. In industry, electrochemical technologies can provide higher purity in technological processes and they can also limit a degradation of the environment in comparison to the common chemical methods. Electrochemistry has been also very useful in developing and in the production of new energy sources. A lot of attention has been paid to studies of environmentally friendly hydrogen fuel cells. The electrochemical techniques of waste degradation can be divided into two main categories: (i) techniques based on the faradaic processes of oxidation or reduction of contamination, and (ii) electrokinetic methods based on the transport of ions or charged particles in the electric field. The electrode processes result in the formation of deposits on the electrode surface or the decomposition of large organic molecules to the low molecular weight, easily biodegradable molecules or CO2. The electrokinetic techniques include electrocoagulation, electroosmosis, electrodialysis, and electroflotation. These techniques are widely used in removing contaminants from soil. This paper is focused on selected topics related to the environmentally friendly application of electrochemistry.

Keywords: environmental protection, electrochemical techniques, hydrogen fuel cells, electrocoagulation, electroosmosis, electrodialysis, electro-flotation, waste electrodegradation, waste degradation, soil decontamination


Wiadomości Chemiczne, 2006, 60, 671.
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SOLID-STATE NMR SPECTROSCOPY AS A TOOL FOR SEARCHING OF POLYMORPHISM OF THE BIOORGANIC DERIVATIVES.

Sławomir Kaźmierski i Marek J. Potrzebowski

Centrum Badań Molekularnych i Makromolekularnych Polskiej Akademii Nauk
ul. Sienkiewicza 112 90-363 Łódź, e-mail: marekpot@cbmm.lodz.pl


Polymorphism is one of the most important and amazing phenomenon in structural chemistry. The knowledge of this phenomenon is crucial both in experimental sciences (e.g.: chemistry, physics and crystallography) and in industry - especially in pharmaceutical industry. It is well known, that polymorphic forms of therapeutic compounds differ in their bioavailability - e.g. the rate of dissolution and equilibrium solubility. In extreme cases, one polymorph may be a medicine whilst the second may be very dangerous or even poisonous. In this light, the possibility to distinguish the desirable form of compound from the useless form, seems to be very important.

In our article, some problems concerning the investigation of polymorphism phenomenon by applications of solid-state NMR are presented. The possibilities of current NMR techniques in searching of polymorphism as well as the practical aspects and applications are presented and discussed.
Keywords: Solid State NMR, polymorphism, N-benzoilphenylalanine. quercetin, ATP hydrates.


Wiadomości Chemiczne, 2006, 60, 723.
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THIO(BISARYLOXO) TITANIUM COMPLEXES-PRECATALYSTS OF ETHENE POLYMERIZATION

Zofia Janas

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


This article concerns methods of synthesis, structural and catalytic characterisation of titanium complexes based on the 2,2'-thiobis{4-(1,1,3,3-tetramethyl-butyl)phenolato (tbop) ligand. In recent years there is a growing recognition that nonmetalocene complexes hold great promise as olefin polymerization catalysts. Most successful developments in terms of catalysis have appeared using chelating bis(aryloxide) ligands, in particular with tridentate and tetradentate ligands having an additional coordinating heteroatoms (N, O, S). The tbop ligand was placed on Ti and several heteroleptic, alkoxo- and aryloxo-bridged complexes containing coligands like chlorides, imides, monoaryloxides as well as homoleptic compound have been prepared and structurally characterised. These complexes when activated with aluminum alkyls are highly effective heterogeneous, well-defined, single-site ethene polymerization catalysts.
Keywords: titanium complexes, bis(aryloxo) ligands, catalysts, olefin polymerization


Wiadomości Chemiczne, 2006, 60, 747.
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1,1-DIAMINO-2,2-DINITROETHENE (DADNE), A NEW HIGH ENERGETIC AND LOW SENSITIVE EXPLOSIVE

Stanisław Cudziło, Zbigniew Chyłek

Instytut Chemii, Wydział Nowych Technologii i Chemii Wojskowej Akademii Technicznej
00-908 Warszawa, ul. Gen. S. Kaliskiego 2


The search for new molecules that combine possibly high performance and simultaneously low sensitivity is one of the directions of development of explosives. In 1998, 1,1-diamino-2,2-dinitroethene (DADNE) was synthesized by N. Latypov et al. using destructive nitration of heterocyclic compounds containing the structural element of acetamidine. Soon it turned out that this comparatively simple structure, which can be synthesized without difficulties, possesses very favorable functional qualities as an explosive.

The structure of DADNE molecule is conducive to creation of inter- and intramolecular hydrogen bonds, and this makes DADNE a very stable (activation energy of 243 kJ/mole), thermally resistant (decomposition above 200oC) and dense substance (1.787 g/cm3). DADNE has favorable oxygen balance and on decomposition the molecule can produce entirely gaseous products (CO, H2O, N2) in the amount of ca. 900 cm3/g. Consequently the performance of DADNE almost equals to the common high explosive RDX (1,3,5-triaza-1,3,5-trinitrocyclohexane), but its sensitivity is comparable with that of TNT (2,4,6-trinitrotoluene). Other advantages of DADNE include excellent compatibility with typical components of explosive formulations and propellants as well as ability to be pressed into mechanically resistant pellets without any additives. The already known properties of DADNE indicate that it can be used on its own or in formulations as a high explosive or propellant component.
Keywords: 1,2-Diamino-2,2-dinitroethene, synthesis, analysis, chemical and explosive properties


Wiadomości Chemiczne, 2006, 60, 763.
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COMBUSTION SYNTHESIS OF NANOMATERIALS

Stanisław Cudziło, Mateusz Szala

Instytut Chemii, Wydział Nowych Technologii i Chemii
Wojskowa Akademia Techniczna, ul. Kaliskiego 2, 00-908 Warszawa


Combustion synthesis or self-propagating high-temperature synthesis (SHS) is a well established method for preparation of many valuable compounds such as: refractory compounds (borides, carbides, nitrides, silicides), oxides (tanthalates, niobates, ferrites, cuprates), intermetallics (aluminides, germanides, nickelides) chalcogenides (sulphides, selenides, tellurides), phosphides, hydrides, and some others. The applications of these compounds can be classified as: cutting tools and polishing powders, resistive heating elements, shape-memory alloys, electrodes, coatings and thin films. Some SHS technologies have found their industrial applications. In Russia, USA and Japan, the SHS powders of inorganic compounds, ceramic insulators, high temperature heaters, shape memory alloy wire, cutting inserts, etc, are produced on an industrial scale. However, it was thought that only large particles (several microns and above) could be obtained by the SHS method [1-3].

It was found recently (Nersisyan et al., 2003-2005), that if the reaction occurs in a medium of molten salt (basically alkali metal halide) and has moderate exothermicity, nanometric size titanium carbide and some of transition metals (Ti, Ta, Nb, Mo) could be obtained by utilization of SHS method. Moreover Huczko at al. (2005) reported that silicon carbide single-crystals in the form of nanofibers and spherical multi-walled carbon nanoparticles and encapsulates could be prepared through the defluorination of poly(tetrafluoroethene) with silicon-containing precursors using the combustion synthesis route. Finally, in 2005, Koch published complete results of a thermodynamic analysis of self-sustaining reaction of fluorinated graphite with magnesium, and reported on detection of single walled carbon nanotubes and carbon nano carpet rolls in the combustion products. This discovery of great importance was patented as a new method of synthesis of carbon allotropes (fullerenes, carbon nanotubes) and various carbon encapsulates. Undoubtedly, it has been demonstrated that SHS offers great potential for generating nanomaterials, including 1D inorganic and carbon nonostructures.

In this review, we discuss the recent developments in the field of combustion synthesis, with special emphasis on the preparation of nanomaterials by low-temperature combustion synthesis (LCS), reductive dehalogenation of halocarbons, and sol-gel combustion synthesis (SCS).
Keywords: combustion synthesis, metal powders, oxides, nanostructures


Wiadomości Chemiczne, 2006, 60, 793.
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THE ROLE OF IONIC LIQUIDS IN PALLADIUM CATALYZED C-C BOND FORMING REACTIONS - SPECIAL INFLUENCE OF IMIDAZOLIUM HALIDES

Anna M. Trzeciak

Uniwersytet Wrocławski, Wydział Chemii, ul. F. Joliot-Curie 14, 50-383 Wrocław


The strategy of modification in chemical processes in order to ensure a safer, cleaner environment in the future is one of the main goal of green chemistry. The basic twelve principles of green chemistry were formulated by P. Anastas and J.Warner in 1998 and accepted by society. Following these principles chemists designing a new process should pay special attention to select substrates and chemicals that minimize their harm to the environment and to human health. Also existing chemical technologies should be modified in a similar way. One approach to achieve this goal is replacement of traditional toxic solvents (mainly VOC,s volatile organic solvents) with ionic liquids presenting a group of liquids or low-temperature melting solid salts of no vapour pressure. Application of ionic liquids in processes catalyzed by transition metal complexes meets two (or in some cases even three) green chemistry rules. The presence of ionic liquids as a solvent in catalytic systems for C-C bond forming reactions like Heck, Sonogashira, Suzuki and carbonylation offers many spectacular advantages including facilitation of catalyst separation from organic products. Elimination even traces of metals from the products of C-C coupling reactions which are used as medicines or agricultural chemicals is extremely important. An article presents catalytic systems containing palladium catalyst precursors, both soluble and heterogenized complexes as well as palladium nanocolloids applied in C-C bond forming processes performed in ionic liquids. The applicability of ionic liquids and influence of their molecular structure on the reaction course is discussed. A special attention is paid to the reactions of ionic liquids with palladium precursors leading to the formation of new species and modification of catalytic properties of the system. It is shown that in many catalytic systems a strong inhibiting effect of imidazolium halides was observed. This fact can be explain on the basis of experimental data by the reaction of imidazolium halide with palladium - aryl intermediate leading to N-heterocyclic carbene complex of lower catalytic activity. Decomposition of palladium - aryl intermediates with formation of phosphonium salts in the presence of imidazolium halide was also observed. In both above mentioned cases a key intermediate in C-C bond forming reactions, that is palladium - aryl halide complex, is eliminated from the reaction mixture causing to decrease of the final product yield.

An article presents a state of knowledge in the field of ionic liquids application in catalysis and formulates expectations for future designing of catalytically active and environmentally friendly palladium based systems for C-C bond forming reactions.
Keywords: green chemistry, palladium, C-C cross coupling, Heck, Suzuki, Sonogashira, carbonylation, N-heterocyclic carbenes, ionic liquids.


Wiadomości Chemiczne, 2006, 60, 819.
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