Wiadomości Chemiczne

Wiadomości Chemiczne, 2005, Vol. 59

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  1. Application of Nuclear Magnetic Resonance to Study Intermolecular Interactions of Organic Ligands and Biomolecules
    Wojciech Bocian, Lech Kozerski

  2. NMR Strategies for the Protein Structure Determination in Solution
    Andrzej Ejchart

  3. NMR Spectroscopy in Structural Studies of Nucleic Acids. Part I.
    Zofia Gdaniec

  4. Differentiation of molecular structures using NMR spectroscopy in liquids
    Adam Gryff-Keller

  5. NMR Studies of Dynamic Systems
    Stefan Jankowski

  6. Basic experimental techniques of NMR spectroscopy in liquids
    Wiktor Koźmiński

  7. Pharmaceutical and Medical Applications of Solid State MAS NMR
    Iwona Wawer, Maciej Pisklak, Katarzyna Paradowska

  8. Chemical Periodicals in Poland - Situation in 2004 - Tentative Valuation
    Janusz Jurczak, Jacek Kijeński, Józef J. Ziółkowski

  9. Notatki Chaotyczne. LV. Profesor Zamojski i "Wiadomości Chemiczne"
    Ignacy Z. Siemion

  10. Natural Bond Orbital
    Piotr M. Wojciechowski

  11. Carboranes and metallacarboranes. Part II. Metallacarboranes
    Agnieszka Olejniczak

  12. Liquid Crystalline Ester Imide Materials
    Andrzej Orzeszko

  13. Vinylphosphonium Salts in Organic Synthesis
    Roman Mazurkiewicz, Rafał Gabański

  14. Steroid Saponins
    Henryk Myszka, Dorota Bednarczyk

  15. Selected Ordered Nanoporous Carbonaceous Materials: Synthesis, Properties and Application
    Jerzy Choma, Mieczysław Jaroniec , Marcin Kloske

  16. Arsenic in Engineering and Environment Elżbieta Kociołek-Balawejder, Daniel Ociński

  17. Ignacy Z. Siemion
    Dwie dusze Ludwika Brunera

  18. Well-defined Ruthenium-based Catalysts of Olefin Matathesis
    Cezary Pietraszuk

  19. Radiation Chemistry in Exploration of Mars
    Zbigniew Paweł Zagórski

  20. The Influence of the Surface Active Agents on Wettability of Low Energetic Hydrophobic Solids
    Bronisław Jańczuk, Katarzyna Szymczyk, Wiesław Wójcik

  21. Preparation of cis-jasmone
    Anna Pawełczyk, Lucjusz Zaprutko

  22. Carbon Nanotubes Purification Processes
    Michał Bystrzejewski, Andrzej Huczko

  23. Notatki Chaotyczne. LVII. Profesor Mastalerz jako egzorcysta
    Ignacy Z. Siemion

  24. Click Chemistry - ARevolution in Organic Synthesis?
    Karol Kacprzak

  25. Anomeric Effect
    Andrzej Nowacki, Andrzej Wiśniewski

  26. Adsorption of Phenols on Activated Carbon
    Andrzej Dąbrowski, Przemysław Podkościelny, Zbigniew Hubicki, Mariusz Barczak, Erich Robens

  27. Sequential Extraction of Metals from Environmental Samples
    Jan Kalembkiewicz, Eleonaro Sočo

  28. The Application of Quercetin, Morin and their Sulfonic Derivatives in Therapy and Food Industry
    Maria Kopacz, Anna Kuźniar

  29. Notatki Chaotyczne. LVIII. O Prawym i Lewym
    Ignacy Z. Siemion

  30. Insect Gonadotropic Peptide Hormones
    Mariola Kuczer, Danute Konopińska

  31. Capillary Electrochromatography - Theoretical Basis and its Applications
    Irena Malinowska, Marcin Drozdowski, Jacek Bojarski

  32. Sodium Water Glasses. Part I. Synthesis and Applications
    Wiesław Kożlak

  33. In the Search for Physicochemical Basis of Homeopathy
    Jacek Tyczkowski, Ewa Tyczkowska-Sieroń

  34. Notatki Chaotyczne. LIX. Cagliostro Démasqué à Varsovie
    Ignacy Z. Siemion

  35. Tools for Combinatorial Chemistry. Part 3. Reaction in Solid Phase Organic Synthesis
    Ryszard Łaźny, Mołgorzata Lipińska, Michał Sienkiewicz

  36. Pegylation - a Method of Modification of Properties of Polypeptidic Drugs and Biologically Active Compounds
    Jakub Ferenc, Katarzyna Kieć-Kononowicz

  37. Plant Signaling Peptides
    Agata Bachyrycz, Danuta Konopińska, Katarzyna Szymanowska

  38. Bioindicators in Environmental Pollution Monitoring - a Review
    Krystyna Srogi

  39. O Potrzebie Luzu
    Ignacy Z. Siemion

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APPLICATION OF NUCLEAR MAGNETIC RESONANCE TO STUDY INTERMOLECULAR INTERACTIONS OF ORGANIC LIGANDS AND BIOMOLECULES

Wojciech Bociana, Lech Kozerskib

aNarodowy Instytut Zdrowia Publicznego, ul. Chełmska 30/34, 00-725 Warszawa
bInstytut Chemii Organicznej, polska Akademia Nauk, ul. Kasprzaka 44/52, 01-224 Warszawa


The title problem is reviewed in the three main areas of general interest to chemists, biochemists and biologists, i.e. mutual interactions of small molecules, ligand to biomolecule binding and interactions of biomolecules. Physical phenomena, specific and nonspecific, such as hydrogen bonding, self association, hydrophobic interactions, etc., are shown as being defined by NMR spectral parameters in solution and solid state.

Diversity of hydrogen bonding encountered in nature is exemplified by the interaction of acetic acid with Watson-Crick vs Hoogsteen faces of adenosine, studied by DNMR in organic solvent at low temperatures. The complementarity of solid state NMR to solution studies of defining the nature of hydrogen bonding is presented in the case of genistein interaction with nitrogen bases.

Application of a title method is presented for searching the geometry of complexes formed of organic ligands and biological molecules. General protocol for searching the geometry of complex is presented for the case of topotecan (TPT) interaction with duplex octamer and nicked decamer duplexes of DNA.

Interaction of biomolecules is presented for the case of duplex octamer DNMR study showing effects of base pairing and stacking on the b 'H values and insulin aggregation as studied by Pulse Field Gradient NMR spectroscopy leading to relating the radius of molecular aggregate with the diffusion constants.

In conclusion it is stated that various NMR techniques in solid and liquid state, coupled with X-ray and MS, constitute modern tool of structural biology in pursue of disclosing functions of biomolecules expressed by their interactions.


Wiadomości Chemiczne, 2005, 59, 3.
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NMR STRATEGIES FOR THE PROTEIN STRUCTURE DETERMINATION IN SOLUTION

Andrzej Ejchart

Instytut Biochemii i Biofizyki PAN, Pawińskiego 5A, 02-106 Warszawa.


A number of reasons have hindered the use of NMR spectroscopy as a tool for the protein structure determination. Recently, the advance in the NMR equipment, spectral techniques and isotope labelling has resulted in an enormous growth of NMR-determined protein structures.

After a brief presentation of protein structure and conformation several types of NMR-derived constraints and the characteristic features of chemical shifts in proteins are discussed. Short-range, distance and dihedral angle constraints are valuable, but cumulative errors can appear when succesive constraints are used to determine spatial relationship of remote parts of a protein. Therefore, long-range constraints derived from residual dipolar couplings are highly complementary to the short-range constraints.

Modern strategies to the NMR-based protein structure determination depend on the size of studied biomolecules. Small proteins (Mcz< 10 kDa) can be studied with the use of two-dimensional (2D) 1H NMR techniques. Medium size proteins (Mcz < 30 kDa) require double isotopic labeling 15N/13C and multidimensional (3D and 4D) heteronuclear techniques. There is no well established strategy to the structure determination of large proteins (Mcz > 30 kDa) yet. The most promising approaches take advantage of triple isotopic labeling 15N/13C/2H and the transverse relaxation optimized spectroscopy (TROSY), both resulting in the reduction of signal width.


Wiadomości Chemiczne, 2005, 59, 23.
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NMR SPECTROSCOPY IN STRUCTURAL STUDIES OF NUCLEIC ACIDS. PART I.

Zofia Gdaniec

Instytut Chemii Bioorganicznej PAN, ul Noskowskiego 12/14, 61-704 Poznań


NMR spectroscopy is a powerful method that allows detetmination of the structure and dynamics of nucleic acids and their complexes in solution with atomic resolution. A major breakthrough in the structure determination of nucleic acids by NMR was introduction of advanced and efficient methods for the labeling of RNA and DNA with 13C and 15N and development of multidimensional, heteronuclear NMR techniques analogous to those used in protein NMR spectroscopy.

The resonance assignment is a crucial step in the NMR study. A spectrum must be assigned before useful structural information can be extracted. The assignment of RNA is considerably more difficult than for DNA of similar size. This is mainly due to the much narrower spectral dispersion of the H2', H3', H4' and H'/5 " ribose protons relative to DNA. The methodology for sequential assignment of nucleic acids via lomonuclear NMR techniques relies on the assumption of helical structure and therefore fails in the case of nonhelical structures, that is typical of RNA.

Development of 13C/15N labeling techniques has afforded heteronuclear multidementional experiments that utilize the favorable properties of 13C and 15N nuclei such as large one-and two-bond heteronuclear scalar coupling constants and large chemical shift dis-persion. These experiments provide increased sensitivity of double and triple resonance experiments and help in overcoming the problem of severe spectral overlap.

Progress in novel NMR methods stimulated also a design of experiments for conformationindependent sequential assignment. In nucleic acids, experiments that correlate base resonances among themselves as well as with sugar resonances allow unambiguous spectral assignment for the structures, where the conventional NOE-based methods may not be applied. Assignments of highly overlapped sugar resonances are facilitated enormously by the application of correlated experiments based on 13C-13C transfer. Additionally, triple resonance experiments allow correlation of neighboring nucleotides through the phosphodiester backbone.

The arsenal of existing methods in structure calculations of nuclcic acids by NMR spectroscopy has recently been extended. For example, NMR methods have been developed to detect and measure scalar couplings via hydrogen bonds. The information about hydrogen bonds provides very useful restraints for structural determination, especially in case of noncanonical motifs.

Furthermore, the use of methods that introduce anisotropic environments for nucleic acids in solution allows the measurement of residual dipolar couplings (RDC). RDCs yield orientation, rather than distance-based constraints. The RDCs contain global structural information on nucleic acids that cannot be obtained by standard solution NMR techniques. These constraints can both improve the local structure of nucleic acids and provide novel data on the global structure.

Another NMR technique, TROSY has been introduced to effectively suppress transverse relaxation of 1H-15N and 1H-13C moieties. TROSY selects exclusively the narrow line of a 1H-15N doublet or 1H-13C multiplet, yielding improved spectral resolution and increased sensitivity of NMR experiment.

Recent advances in solution NMR techniques provide tools for structural studies of large (> 30 residues) nucleic acids molecules.


Wiadomości Chemiczne, 2005, 59, 47.
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DIFFERENTIATION OF MOLECULAR STRUCTURES USING NMR SPECTROSCOPY IN LIQUIDS

Adam Gryff-Keller

Wydział Chemiczny Politechniki Warszawskiej, ul. Noakowskiego 3, 00-664 Warszawa


The high resolution NMR spectroscopy in liquids is a convenient tool for differentiating stereoisomers. Diastereomeric structures having different spatial distribution of electron density produce different magnetic environments for their nuclei and in consequence have, in general, different NMR spectra. The same concerns diastereotopic groups in a molecule. On the other hand, enantiomers or enantiotopic groups can be differentiated only when they are placed in a chiral environment. It can be accomplished by transforming enantiomers into their diastereomeric derivatives with the aid of chiral derivatising reagents, or by using chiral complexing or solvating agents. The most popular methods of practical realization of these approaches have been reviewed and illustrated with some examples. The spectroscopic differentiation of enantiomers provides a possibility of determining their absolute configurations.


Wiadomości Chemiczne, 2005, 59, 67.
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NMR STUDIES OF DYNAMIC SYSTEMS

Stefan Jankowski

Instytut Chemii Organicznej, Politechnika Łódzka, Żeromskiego 116, 90-924 Łódź


The dynamic NMR (DNMR) deals with different techniques for rate constant determination for different chemical processes. The complete band shape analysis is applicable to the study of processes occurring with rate constants between 1 and 104 s-1. The measurements of relaxation times are useful for faster processes with rate constants of the order of 102-106 s-1 and the spin-saturation technique can be applied for slower processes (k = 0,1-100 s-1). Kinetic measurements by EXSY experiment are applicable for rate constants between 10-2 and 102 s-1. The advantages and pitfalls of every method were discussed.


Wiadomości Chemiczne, 2005, 59, 93.
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BASIC EXPERIMENTAL TECHNIQUES OF NMR SPECTROSCOPY IN LIQUIDS

Wiktor Koźmiński

Wydział Chemii Uniwersytetu Warszawskiego, ul. Pasteura 1, 02-093 Warszawa


General overview of most important NMR techniques and applications for organic and bioorganic molecules in liquids is given. The sensitivity of NMR experiments is discussed with regard to nuclear properties, B field, applied method of excitation and detection, and finally concentration. In the next chapter the principles and consequences of quadrature detection are discussed. The most important techniques of quadrature detection in directly and indirectly detected domains are exemplified. In the next point the principles, advantages and disadvantages of coherence selection techniques via phase cycling and Pulsed Field Gradients are indicated and compared with respect to various applications.

In the last part of present article the most important homo- (COSY, TOCSY, NOESY, and ROESY) and heteronuclear (HSQC, HMQC/HMBC) techniques used in NMR investigations in liquids are briefly reviewed. The characteristic features and experimental problems of these methods are discussed with respect to usual applications in chemistry and biochemistry.


Wiadomości Chemiczne, 2005, 59, 107.
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PHARMACEUTICAL AND MEDICAL APPLICATIONS OF SOLID STATE MAS NMR

Iwona Wawer, Maciej Pisklak, Katarzyna Paradowska

Zakład Chemii Fizycznej, Wydział Farmaceutyczny Akademii Medycznej, ul. Banacha 1, 02-097 Warszawa


Some characteristic features, distinguishing NMR in solution and solid phase, are briefly described. The techniques of magic angle spinning, cross-polarization, as well as the experiments with variable cross-polarization time and dipolar-dephasing pulse sequences are illustrated. The spectra measured for solutions are frequently used as an aid in the assignment of solid-state ones. The differences Δ=δsolutionsolid state are explained in terms of conformational effects (resulting from frozen intramolecular reorientation in the solids) and intra- and intermolecular interactions (hydrogen bonds and also short intermolecular contacts in the crystals).

Solid-state NMR spectroscopy has become an important technique in the field of pharmaceutical sciences. Solid-state techniques are used for the characterization of pharmaceutical solids: drug substances and dosage forms (tablets) and their mutual interactions. Structural information on solid antibiotics (penicillin salts, erythromycin A, chloramphenicol and its derivatives), anticoagulants (warfarin, sintrom), antimalaria (artemizinin) or anxiolytic drugs (buspirone and its analogues) was obtained by the analysis of 13C CP MAS spectra. Frequently exploited area is polymorphism because pharmaceutical polymorphs can display different solubilities, dissolution rates and bioavailability. Polymorphic forms of steroids (testosterone, prednisolone, cortisone) and 4-azasteroids (finasteride) and of numerous other drugs (e.g. AZT, paracetamol, phenobarbital) have been detected. Solid-state NMR has thus an ability to differentiate polymorphs, determine asymmetry in the crystal unit cell and investigate molecular motions within the solids.

MAS NMR spectra can be recorded for powdered tablets, enabling fast identification of the active substance. Few examples of forensic applications include "Extasy" and Viagra tablets. The technique ideally lends itself to the studies on drugexcipients interaction, possible conversions of the drug during processing and storage can be followed.

Multinuclear solid state NMR is also useful in characterization of materials and tissues removed during surgery (bones, brain tumors, urinary stones).


Wiadomości Chemiczne, 2005, 59, 121.
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CHEMICAL PERIODICALS IN POLAND - SITUATION IN 2004 - TENTATIVE VALUATION

Janusz Jurczak1, Jacek Kijeński2, Józef J. Ziółkowski3

1Wydział Chemi, Uniwersytet Warszawski, ul. Pasteura 1, 02-093 Warszawa,
2Instytut Chemi Przemysłowej im. I. Mościckiego w Warszawie, ul. Rydygiera 8, 01-793 Warszawa,
3Wydział Chemii, Uniwersytet Wrocławski, ul. F. Joliot-Curie 14, 50-383 Wrocław


The analysis of chemical periodicals in Poland in 2004 have been ordered by Pol ish Academy of Science, the Committe for Chemistry and presented in three parts.

In Part 1 (Józef J. Ziółkowski) are presented:

- journals of scientifics character, printed in english, english and polish and german (Group A)

- journals printed in polish (Group B)

- journals printed as scientitics bulletins edited by the univeristes or research institutes (Group C)

- popularized scientific or commercial journals (Group D) and

- the books publication, special issues usually for didactic purposes (Group E).

In Part II (Jacek Kijenski) are disscussed chemical periodicals addressed to science, technology and industrial chemistry mainly related to environmental chemistry, polymers, fuels, energy problems, and raw materials.

In Part III (Janusz Jurczak) is presented opinion about location of polish chemical periodicals in Europe.

Presented above analysis is probably the first complex valuation and although not complete may stimulate further discussion on strategy of development of chemical periodicals in Poland.


Wiadomości Chemiczne, 2005, 59, 139.
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Notatki Chaotyczne. LV. Profesor Zamojski i "Wiadomości Chemiczne"

Ignacy Z. Siemion

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



Wiadomości Chemiczne, 2005, 59, 157.
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NATURAL BOND ORBITAL

Piotr M. Wojciechowski

Wydział Chemiczny, Politechnika Wrocławska, ul. Smoluchowskiego 23, 50-372 Wrocław


Natural bond orbital (NBO) analysis based on Löwdin's concept of "natural'' orbitals [1] is used to describe the unique set of orthonormal 1-electron functions and to express the density Θi(r) of ρ(r) Ψ. Natural bond orbitals are typically localized orbitals and provide the most accurate possible "natural Lewis structure'' pattern of Ψ, because all orbital details like polarization coefficient or atomic hybrid composition are mathematically chosen to include the highest possible percentabe of the electron density [2].

This concept adapted by Frank Weinhold and co-workes in NBO's package [3] provides the information about charges, bond types, hybrid directions, resonance weights, bond orders, etc. The NBO program comprises a sequence transformation from the input basis set to various localized basis sets, including natural atomic (NAO), hybrid (NHO), and (semi-)localized molecular orbital (NLMO) sets.

Widespread acceptance of the NBO paradigm by scientist in all fields of chemistry results in over 500 published applications per year. NBO-based techniques are being employed from donor-acceptor intermolecular interaction [4], and particular effectiveness in elucidating resonance-type stereoelectronic and steric factors, to nature of H-bonding in clusters, liquids and enzymes [5], and analysis of electronic principles of photexited and radical species.


Wiadomości Chemiczne, 2005, 59, 193.
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CARBORANES AND METALLACARBORANES
PART II. METALLACARBORANES

Agnieszka Olejniczak

Laboratorium Wirusologii Molekularnej i Chemii Biologicznej
Centrum Biologii Medycznej PAN
ul. Lodowa 106, 93-232 Łódź
tel. (48-42) 6771237, fax. (48-42) 6771230; e-mail: aolejniczak@cbm.pan.pl


Metallacarboranes are cluster compounds that incorporate metal atoms and hydrides of carbon and boron in their polyhedral skeleton. A large number of metals such as Sc, Cr, Mg, Fe, Co, Ni, Cu, Zr, Mn, Ru, Pd, Yb, Ta, Pt, Au have been incorporated as cluster vertices.

The chemistry of metallacarboranes originated with observation that the open face of dicarbollide ion (C2B9H112-) is very similar to the cyclopentadienyl ligand (Cp-) and can form metallacarboranes in the same way as Cp- forms sandwich type complexes.

Metallacarboranes are stable, colored crystalline solids that are soluble in organic solvents and well survive exposure to air. Many of them undergo reversible chemical or electrochemical oxidation and reduction. Metal-carborane complexes find an increasing number of applications in catalysis, siloxane-linked polymers, solvent extraction of radionuclides from nuclear waste, materials for nonlinear optics, medicinal diagnosis and treatment, and others.


Wiadomości Chemiczne, 2005, 59, 213.
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LIQUID CRYSTALLINE ESTER IMIDE MATERIALS

Andrzej Orzeszko1, 2

1 Katedra Chemii, SGGW w Warszawie, ul. Nowoursynowska 159C, 02-787 Warszawa
2Instytut Chemii, Wojskowa Akademia Techniczna w Warszawie, ul. Kaliskiego 3, 00-908 Warszawa


The credit for the discovery of liquid crystals must go to F. Reinitzer who in a paper submitted on May, 1888 described his observations of the colored phenomena occurring in melts of cholesteryl benzoate [9]. He noted the "double melting" behavior in this case, whereby the crystals transformed at 145,5°C into a cloudy fluid, which suddenly clarified only on heating to 178°C.

Mesophases are a state of order between crystals and liquids. They have imperfect long range orders of orientation and/or position. Thus, they can be fluid like a liquid and they can have anisotropic properties like crystals. The liquid crystals have a predominating orientational order [1].

Despite intensive research activities of numerous research groups on polymers no systematic study on liquid crystalline polyimides had been published before 1985. Only two patents of Du Pont filed in 1979 reported on LC poly(ester imide)s [14, 15]. The fundamental study on this area was made by Kricheldorf [16-38]. He found that the most promising substrate for synthesis of liquid crystalline poly(ester imide)s was trimellitic anhydride. It forms imide ester mesogenic group in main polymer chain.

On the other hand it has been found that isolated phthalimide moiety not favor liquid crystalline order [47] but connected with ester groups increases a possibility of forming mesophase.

Low molecular weight cholesteric ester imides with oxyethylene spacers form liquid crystal SmA2 phase. It is possible due to microsegregation of hydrophobic parts of molecules [48, 50, 53]. Similar compounds with polymethylene spacers exhibit monolayer SmA phase. In this case microsegregation is impossible.

Also ester imides based on biphenyl mesogenic moiety show termotropic behavior [49, 51, 52]. Cyanobiphenyl derivatives of such trimellitimides form a partially bilayered smectic Ad phase for the homologues with long N-alkyl substituents [51]. The monolayer smectic A1 phase was observed for all members of 4'-undecyloxybiphenyl derivative series while the longer homologues exhibited SmA-SmC dimorphism.

The reaction of imide compounds with Lawesson's reagent leads to monothio- and dithioimides, respectively. Liquid crystalline ester thioimides were obtained at first time by Orzeszko and Białecka [56]. An incorporation of one or two sulfur atoms into an imide ring results in reduction of phase transition temperature values. This is a consequence of the considerable change of compound polarity and the increase of the molecular breadth.


Wiadomości Chemiczne, 2005, 59, 231.
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VINYLPHOSPHONIUM SALTS IN ORGANIC SYNTHESIS

Roman Mazurkiewicza, Beata Fryczkowskab, Rafał Gabańskia

aKatedra Chemii Organicznej, Bioorganicznej i Biotechnologii Politechniki Śląskiej, ul. B. Krzywoustego 4, 44-100 Gliwice, romanm@zeus.polsl.gliwice.pl
bInstytut Inżynierii Tekstyliów i Materiałów Polimerowych, Akademia Techniczno-Humanistyczna, ul. Willowa 2, 43-309 Bielsko-Biała


Vinylphosphonium salts are known for more than a century, but they started to attract significant attention of organic chemists only since 1964 when Schweizer demonstrated that the Michael addition of a nucleophile with a carbonyl function to vinylphosphonium salts results in phosphorus ylides, which can undergo the intramolecular Wittig reaction to carbo- and heterocyclic systems (Scheme 2) [1,2].

The main synthetic routes to vinylphosphonium salts and a variety of their applications in organic syntheses are considered in detail in this review. Particular attention is given to the application of vinylphosphonium salts as versatile building blocks for syntheses of carbo- or heterocyclic systems in reactions with carbon, oxygen sulphur or nitrogen nucleophiles containing in a molecule a carbonyl function.


Wiadomości Chemiczne, 2005, 59, 249.
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STEROID SAPONINS

Henryk Myszka, Dorota Bednarczyk

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


Chemistry and biochemistry of glycoconjugates have been a serious challenge for scientists since many years. Among the huge number of glycoconjugates there is a large group of compounds called saponins, specific glycosides that can be found in many plants. However, they can also be collected from some marine organisms. Nowadays, the main source of saponins is the flora of tropical and temperate zones, such a kind of plants: Costus, Discorea, Paris, Solanum, Trigonella, Trillium and Yucca. Furthermore, the large quantities of saponin can be found in food and beverage plants, including oats, peanuts, soybeans, garlic, onion, spinach, leafs of tea, etc. They are active components of some herbs used in therapeutics, e.g. in Poland the fenugreek seeds are used as a decoction for treatment of skin inflammation, moreover they are the components of antisnoring drops, as well as a part of nutrients for culturists. In Orient countries the number of saponins have long been used as pharmaceutical agents, such as those from ginseng, red clover, licorice, horse chestnut, senega and from many others traditional Chinese herbal medicinal plants [1, 2, 27].

The popularity of the discussed group of glycosides comes from their interesting bioactivity. Biological investigations showed that saponins stop the sedimentation process of lipids on the aorta-wall, they slow down the production of sugars, proteins, lipids and bile acids in the liver. Furthermore, they are good antifungal and antibacterial agents, also show an anti-inflammatory and antiallergic activity. It has been found that the crude extract of some plants, especially in the aerial portion, containing the diosgenin glycosides display anti-neoplastic properties against several strains of human cancer cells [4?9].

Structurally, the saponins are classified as steroid or triterpenoid glycosides depending upon the nature of the aglycone, which is generally called sapogenin. The steroid saponins have cyclopentaphenantrene backbone in aglycone, for example diosgenin, tigogenin, sarsapogenin. Saponins containing nitrogen in aglycone backbone belong also to this group. Triterpenoid saponins have usually 30-carbon atoms in tetra- or pentacyclic aglycone. The carbohydrate residue (hydrophilic part of glycosides), usually a mono-, di-, tri- or tetrasaccharide, is covalently attached to the sapogenin backbone (hydrophobic element). The sugar moiety, in most saponins, is attached to the 3-OH of a sapogenin via the 1,2-trans-glycosidic bond. The difficulties in isolation of homogeneous saponins from natural sources prompted chemists to the synthesis of these type compounds. Chemical synthesis could provide a real way to the availability of required saponins [10?104].

The largest and also the most interesting class of saponins is the first group - the steroid saponins, because of their biological activity. To this group belong three class of compounds: cholestanoic, furostanoic and spirostanoic saponins.


Wiadomości Chemiczne, 2005, 59, 275.
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SELECTED ORDERED NANOPOROUS CARBONACEOUS MATERIALS: SYNTHESIS, PROPERTIES AND APPLICATION

Jerzy Choma1,3, Mieczysław Jaroniec2, Marcin Kloske3

1Instytut Chemii Akademii Świętokrzyskiej, ul. Chęcińska 5, 25-020 Kielce
2Department of Chemistry, Kent State University, Kent, Ohio 44-242, USA
3Instytut Chemii Wojskowej Akademii Technicznej, ul. Kaliskiego 2, 00-908 Warszawa


This article presents the current state of the research on ordered nanoporous carbonaceous materials. A grownig interest in these nanostructured materials results from their numerous potential applications in various areas of science, material engineering and technology, e.g.: biomedical science, electronics, physics, electrochemistry, etc. In this work we described the methods for synthesis of ordered nanoporous carbonaceous materials as well as their physicochemical properties. Also, a brief discussion of methods for characterization of carbons is presented. A special emphasis is given to adsorption, thermogravimetry, X-ray diffraction and transmission electron microscopy, which are commonly used in materials science. The carbon materials discussed in this work have been alredy used to obtain novel structures such as: nanometer sized carbonaceous fibrils, rods and tubules, which have already found some practical applications.


Wiadomości Chemiczne, 2005, 59, 305.
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ARSENIC IN ENGINEERING AND ENVIRONMENT

Elżbieta Kociołek-Balawejder, Daniel Ociński

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


The arsenic is an element which comes in the twentieth place in respect of its dissemination in the earth's crust and fourteenth in seawater. Average concentrations of arsenic in the earth's crust are reported to be 1,5 - 6 mg/kg [4, 5, 7-11]. In the geosphere arsenic occurs connected especially with sulfide minerals. As a chalcophylic element it is commonly present in sulfide ores of other metals, mainly pyrites, chalcopyrites, galenite and zincblende. Arsenic is a constituent of more than 200 minerals (tab. 2).

Sources of arsenic in the environment are natural and anthropogenic in essence. More than several dozens tons of arsenic are released annually to the terrestrial and aquatic environment and to the atmosphere [6, 11, 12].

Natural sources of arsenic include volcanic activity, weathering, soil erosion, forest and grass fires and biological activity. Anthropogenic sources are mainly smelting of non-ferrous metal ores and burning of fossil fuel in household and power plants [7, 10, 16]. Anthropogenic sources also include the production and application of arsenic compounds (tab. 4). From ages they were used in medicine, metallurgy and dye-production. In the last few hundred years arsenic compounds were also used in agriculture, wood-preservation, warfare production and semiconductor industry. In XVIII and XIX centuries the essential usage of arsenic was medicine. Until the discovery of antibiotics arsenotherapy was applicable in the treatment of a majority of diseases (fig. 3). In the XX century the most important applications arsenic compounds have found in agriculture and wood-preservation (fig. 5). In the first half of that century about 90% of the arsenic produced was used to manufacture a variety of pesticides, herbicides and fungicides. The utilization of arsenic compounds was systematically limited along with increasing of the ecological consciousness. Nowadays the use of arsenic in medicine and agricultural is declining. The most of the produced arsenic is used to manufacture Chromated Copper Arsenate (CCA) a wood preservative which is going to be replaced by alternative preservatives in the near future [81]. Small amounts of arsenic are utilized in the semiconductor industry, metallurgy and in the manufacturing of glass. Most of the arsenic is produced in form of arsenic trioxide, which is a by-product during the smelter of nonferrous ores.

Arsenic compounds are mobile in environment and occur in natural waters, soils and in the air. Arsenic is mainly transported by water among environmental media and it is undergoing chemical and physical transformations (oxidation/reduction, metylation/demetylation, adsorption/desorption). In natural environment arsenic occurs mainly as inorganic species: arsenate and arsenite. In these chemical compounds certain bacteria can replace hydroxyl groups by methyl groups forming methyl derivatives, mainly monomethyl arsonic acid (MMAA) and dimethyl arsenic acid (DMAA). Methylated arsenic species can be transformed by bacteria, fungi and yeasts under anaerobic conditions to volatile forms of arsenic: monomethylarsine (MMA), dimethylarsine (DMA), trimethylarsine (TMA) and arsine (AsH3) (fig. 9). In the air arsenic exists mainly adsorbed on particle matter in the form of arsenic trioxide, arsenate and arsenite.

Arsenic compounds are toxic for humans and animals. The toxicity depends mainly on the chemical forms and oxidation states of arsenic, the most toxic are inorganic arsenites. Ingestion of a large dose of inorganic arsenicals can lead to death (tab.6). A long-term exposure to arsenic increases risks of cancer in skin, lungs, bladder and kidney. Inorganic arsenicals have been classified as Group I carcinogens [136].

This review represents a comprehensive knowledge about the present and old applications of arsenic, the anthropogenic sources of this element, the circulation of arsenic in the environment and its impact on human health.


Wiadomości Chemiczne, 2005, 59, 353.
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NOTATKI CHAOTYCZNE. LVI. DWIE DUSZE LUDWIKA BRUNERA

Ignacy Z. Siemion

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



Wiadomości Chemiczne, 2005, 59, 387.
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WELL-DEFINED RUTHENIUM-BASED CATALYSTS OF OLEFIN MATATHESIS

Cezary Pietraszuk

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


Olefin metathesis has become an important synthetic tool in organic and polymer chemistry. The family of ruthenium based catalysts tolerant of normal organic and polymer processing conditions and preserving their catalytic properties in the presence of the majority of functional groups has allowed a great number of new applications. The monograph gives a review of literature on well-defined ruthenium catalysts of olefin metathesis published till the end of 2004. The activity of catalytic systems based on different ruthenium complexes in metathetic reactions has been characterised. The methods of obtaining alkylidene complexes of ruthenium showing catalytic activity in olefin metathetic tranformations have been described together with the reactions in which these compounds can be used as precatalysts.

Because of a large body of literature data on Grubbs catalysts and their significance in synthesis, much space is devoted to them, including the methods of their synthesis and the known processes leading to their decomposition. Elements of the mechanism of olefin metathesis the presence of Grubbs catalysts of the 1st and 2nd generation are presented together with the consequences for designing of new catalysts of the process. The catalysts containing a chelating alkylidene ligand, in particular the Hoveyda-Grubbs catalysts arousing increasing interest and already commercially available, have been discussed. Moreover, the paper provides characterisation of the cationic alkylidene complexes described by Hoffmann, allenylidene, vinylidene and alkylidynehydride complexes described by Werner. Preliminary results on obtaining chiral alkylidene ruthenium catalysts and their use in the asymmetric synthesis are also presented. Regarding a number of prospective commercial applications of metathesis in organic synthesis, the current status of the study on heterogenization of alkylidene ruthenium complexes in order to obtain active and stable catalysts for multiple use was described. The paper ends with a list of the most important, in the opinion of the author, monographs and review works on the application olefin metathesis catalysed by well-defined alkylidene complexes in organic and polymer synthesis.

Keywords: olefin metathesis, ruthenium alkylidene complexes, catalysts of olefin metathesis, organic synthesis, polymer synthesis


Wiadomości Chemiczne, 2005, 59, 405.
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RADIATION CHEMISTRY IN EXPLORATION OF MARS

Zbigniew Paweł Zagórski

Zakład Chemii i Techniki Radiacyjnej, Instytut Chemii i Techniki Jądrowej, ul. Dorodna 16, 03-195 Warszawa


The discussion of chemical reactions caused by ionizing radiation is started, as usual, with the nature of the object which absorbs the energy. First, the composition (CO2 = 95.3%) and density of martian atmosphere is discussed; the latter is low, 120 times smaller than over the Earth and does not protect the surface of Mars from ionizing radiations. The atmosphere over the Earth secures the shield equivalent to 3 m of concrete, with many positive consequences for the Life on Earth. In addition, high energy protons from the Sun are diverted magnetically around the Earth, and that is not the case around the Mars. The radiolysis of Martian atmosphere starts with formation of CO2+ as the primary product of single ionization spurs. The multi-ionization spurs can yield exotic carbon-oxygen compounds, not explored yet. Anyway, the radiolysis of martian atmosphere is completely different from the case of Earth, where the primary product is N2+ ion-radical. The lack of water vapor over Mars prevents the formation of an analogue to acid rains, and of creation of many other compounds.

The most interesting feature of Martian regolith is the possibility of the pre-sence of hydrated minerals, which could have been formed milliards years ago, when (probably) water was present on Mars. Water present in the crystalline lattice undergoes only limited radiolysis, as it is known from the case of concrete, produced as biological shield build on Earth, around the sources of ionizing radiation. Formation of natural hydrated silicates on Mars was possible, therefore survival of traces of H2O on Mars is possible. However, this kind of water cannot be recovered easily, to be used by Mars explorers.

The interface of the atmosphere and the regolith is probably the site of many chemical reactions. Very intensive UV, which includes part of the vacuum UV, can cause reduction of carbon dioxide to methane, recently discovered in traces over Mars, hopefully, but erroneously connected, in the mode of wishful thinking, to the Life. Minerals like sodalite, discovered on Mars can contribute as reagents in the mentioned reaction, and could be the source of hydrogen.

Conclusions are dedicated to questions of the live organisms connected with exploration of Mars; from microorganisms, comparatively resistant to ionizing radia-tion, to human beings, considered not to be fit to manned flight, survival on Mars and return to Earth. The genius of Mankind which is able to create effective means of exploration over the distance of millions of kilometers, should be a satisfaction more important than the extremely expensive presence of man or woman on Mars.

Keywords: atmosphere of Mars, manned exploration of space, origins of life, prebiotic chemistry, radiobiology, regolith chemistry


Wiadomości Chemiczne, 2005, 59, 469.
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THE INFLUENCE OF THE SURFACE ACTIVE AGENTS ON WETTABILITY OF LOW ENERGETIC HYDROPHOBIC SOLIDS

Bronisław Jańczuk, Katarzyna Szymczyk, Wiesław Wójcik

Zakład Zjawisk Międzyfazowych, Wydział Chemii, Uniwersytet Marii Curie-Skłodowskiej, Pl. Marie Curie-Skłodowskiej 3, 20-031 Lublin


The paper reviews the thermodynamic of the most important problems of wett-ability of a solid and correlation between adsorption of surface active agents at water-air, and solid-air interfaces and wettability of hydrophobic low-energy solids.

Three types of wetting have been considered; spreading wetting, adhesional wetting and immersional wetting. The usefulness of the Good and Girifalco, Fowkes, Owens and Wendt, and van Oss et al. approaches to interfacial free energy of liquid-liquid and solid-liquid for determination of work of spreading, immersion and adhesion is presented. The correlation between the work of spreading, immersion and adhesion and contact angle is also shown.

On the basis of the contact angle the relationship between wettability of the solids and its surface free energy and surface tension of liquid is discussed. Zisman found for low-energy solids a straight linear relationship between cosθ (θ is the cotact angle) and surface tension of liquids or aqueous surfactant solutions. The extrapolation of this relationship to cosθ=1 allows estimation of the liquid surface tension required to give a contact angle to zero degree, which Zisman described as the critical surface tension. However, in contrary to Zisman, Bergeman and van Voorst Vader, stated that there is straight linear relationship between the adhesional tension (γLV cosθ) and surface tension γLV, of aqueous solution of several types of surface active agents (surfactants). Such relationship was also confirmed by other investigators, however, the different equations describing the wettability of the same solids than Bergeman and van Voorst Vader by aqueous solutions of surfactants has been suggested.

A direct method to investigate relative adsorption at interfaces is described. The usefulness of Lucassen-Reynders equation derived from Young and Gibbs equations for the studies of the correlation between adsorpion of the surface active agents at water-air and solid-water interfaces and wettability of low-energy hydrophobic solids is discussed.

We proved that on the basis of the surface tension of low-energy hydrophobic solids, surface tension of aqueous solution of surfactants or their mixtures, and Fowkes approach to interfacial tension the wettability of low-energy hydrophobic solids can be predicted.

Keywords: adhesion, adsorption, wettability, spreading coefficient, contact angle, critical surface tension of wetting, surface active agents


Wiadomości Chemiczne, 2005, 59, 489.
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PREPARATION OF cis-JASMONE

Anna Pawełczyk, Lucjusz Zaprutko

Katedra i Zakład Chemii Organicznej, Wydział Farmaceutyczny, Akademia Medyczna im. Karola Marcinkowskiego, ul. Grunwaldzka 6, 60-780 Poznań


The "jasmine chemistry" started in 1899 [6]. cis-Jasmone, a naturally occuring derivative of cyclopentenone is an important constituent of the essential oil of the jasmine flowers. It occurs in jasmine oil at the amount of 2-3%. cis-Jasmone can be obtained from fresh flowers by means of time-consuming and laborious extraction process, known as enfleurage [8, 9] and that is why it has been the object of number synthetic efforts.

3-Methyl-2-(2-cis-penten-1-yl)-2-cyclopenten-1-one is a chemical name of cis-jasmone. From a structural point of view it is a relatively simple compound which has been synthesized many times via many different pathways. Since pioneering works of Treff and Werner [4] (Scheme 1) and then Hunsdiecker [17] (Scheme 2) efforts to develop efficient syntheses of this compound have been developed to find more economical procedure. Commercial synthesis of jasmone is based on the alkylation reaction of 3-methyl-2-cyclopentene-1-one using cis-pentenyl chloride in the rpesence of PTC catalyst (Scheme 9) [9, 29, 30]. Because of the difficulty with its manufacturing, the price is still relatively high.

The present short review desribes methods of cis-jasmone preparation. Very interesting and economical group of methods seems to be the group that involves furan derivatives such as furfural, 2-methylfuran, furfuryl alcohol. The major disadvantage of this route are rather vigorous hydrolytic conditions that are necessary for opening the furan ring, which sometimes leads to undesired changes in the molecule (Schemes 2-12). Other cyclic compounds, cyclopentadiene for example, canalso be used to conduct synthesis of cis-jasmone (Schemes 14-17). The most common and successful method to obtain correctly 2,3-disubstituted cyclopentenone is based on the preliminary preparation of unsymmetrically substituted 1,4-diketones. These usuful intermediates are subsequently cyclized under bacis conditions to jasmone (Schemes 18-36). Synthetic ways connecting furan derivatives and cyclization of 1,4-diketones were firstly indicated in 1942 by Hunsdiecker [17], who carried out a complete synthesis of jasmone from 5-methylfuralaldehyde (Scheme 2). Syntheses of jasmone have been reported by many authors but most of those routes are either too lengthy or involve expensive chemicals. This molecule is still a popular synthetic goal and the wealth of different new methods has been published.

Keywords: jasmine, cis-jasmone, fragrance substance, furan derivatives, 1,4-diketones


Wiadomości Chemiczne, 2005, 59, 509.
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CARBON NANOTUBES PURIFICATION PROCESSES

Michał Bystrzejewski, Andrzej Huczko

Pracownia Fizykochemii Nanomateriałów, Wydział Chemii, Uniwersytet Warszawski, ul. Pasteura 1, 02-093 Warszawa


The discovery of carbon nanotubes (CNTs) and the recognition of their exceptional physical properties have generated a great deak of interest. The possible application arise from the remarkable properties of CNTs such as the highest Young's modulus, highest thermal conductivity, ballistic electron transport, and high aspect ratio structure. To date, development of nanotube-based products has been delayed by a lack of availability of quantities of pure material and lack of control of their growth.

There are many methods for CNTs production: carbon arc, chemical vapour deposition of hydrocarbons, laser ablation or electrolysis in molten salts. Each of these methods leads to the raw product, which contains albo by-products: amorphous and turbostratic carbon, carbon nanoonions and encapsulates, catalyst nanoparticles, along with the carbon nanotubes. As mentioned above, high-purity CNTs are required in order to retain excellent intrinsic properties and to proceed with further realistic applications. This review presents not only various routes on nanotubes properties are also discussed.

Keywords: Carbon nanotubes, purificationm, electron microscopy, Raman spectroscopy


Wiadomości Chemiczne, 2005, 59, 537.
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Notatki Chaotyczne. LVII. PROFESOR MASTALERZ JAKO EGZORCYSTA

Ignacy Z. Siemion

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



Wiadomości Chemiczne, 2005, 59, 557.
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CLICK CHEMISTRY - AREVOLUTION IN ORGANIC SYNTHESIS?

Karol Kacprzak

Zakład Stereochemii Organicznej, Wydział Chemii, Uniwersytet im. Adama Mickiewicza, ul. Grunwaldzka 6, 60-780 Poznań


In 2001 prof. K.B. Sharpless from Scripps Institute has announced a new idea for an easier and faster molecular discovery, named click chemistry. This concept bases on the following observations:

Click chemistry embraces therefore a set of powerfull reactions which must be modular, wide in scope, highly yielding, generating easily removable byproducts (with no need for chromatographic purification) and stereoselective. These reaction should be also insensitive to oxygen and water and preferably carried out under simple conditions. Click reactions achieve their efficienty due to the high thermodynamic driving force, usually greater than > 20 kcal/mol (thus can be recognized as spring-loaded for a single trajectory). Examples of this reactions include: nucleophilic opening of strained rings (epoxides, aziridines), cycloadditions (e.g. 1,3-dipolar or Diels-Alder type reaction), additions to carbon-carbon multiple bond (epoxidation, dihydroxylation, Michael addition) and some types of carbonyl chemistry (Scheme 1).

An illustration of this concept is multigram 4-step synthesis of products 2a and 2b (Scheme 2) without the use of chromatography. Click chemistry idea was discussed in detail by Sharpless in [1] and [4].

Huisgen 1,3-dipolar cycloaddition is cream of the crop of various click reactions and was used in many notable applications of click chemistry concept, highlighted in this review. This reaction is strongly thermodynamically activated (35-50 kcal/mol), modular and of wide scope, it shows also perfect atom economy and provides products with high yield after usually simple workup. Moreover, due to the stability of reactants and 1,2,3-triazoles to various reactions conditions, including oxygen and water, this cycloaddition can be carried out in water [7-10].

Target guide synthesis combined with 1,3-dipolar Huisgen reaction was used for finding new, most potent (active in femtomolar concentration) acetylcholine esterase inhibitors (Scheme 4) [14-15] and carbonic anhydrase inhibitors 5a,b (Scheme 5) [16]. Other inhibitors developed by synthesis and screening of 1,2,3-triazole libraries include α-1,3-flukosyltransferase VI (Scheme 6) [17], HIV-protease (Scheme 7) [18]. 1,3-Dipolar cycloaddition was also used for modification of antibiotic tyrosidine [19] and vancomycine [20] and the modified products 10a,b and 11a,b exhibit better therapeutic index and activity respectively. Important applications of Huisgen reaction in molecular biology include bioconiugation and labeling techniques. Cowpea virus was efficiently labeled by fluorescein derivatives (Scheme 8) [22] and cell surfaces were decorated by various biotin derivatives (Scheme 9) [23-24] using appropriate azide-alkyne components. Click chemistry in this field was also used for designing new methods for labeling protein (Scheme 10) [25-26], in vitro or in vivo protein profiling (Scheme 11) [27] and DNA sequencing (Scheme 12) [28].

Many important applications of 1,3-Huisgen cycloaddition are found in material chemistry. These include efficient synthesis of dendrimers without the use of chromatography (Scheme 13) [31] or dendronised polymers (Scheme 14) [32]. 1,2,3-Triazole linker formation was utilized for functionalisation of poly(norbornenes) (Scheme 15) [33], modular copolymer synthesis (Scheme 16) [34] and silicon waffers [37] or gold surface [38] modification (Scheme 18). 1,3-Dipolar cycloaddition was also used in the synthesis of new fluorescent cumarines 54 [39], two-photon absorption chromophores 55 [40] and water-soluble calixarenes 56 [41].

Huisgen reaction was recently widely explored for modification of natural products and biomolecules and many interesting 1,2,3-triazole derivatives of sugars, aminoacids and peptides, lipids, steroids and alkaloids were synthesized (62-74) [29, 42-52].

In summary, in a relatively short period of time after its introduction, click chemistry concept was widely approved in various areas and resulted in many important applications. Thus it can be regarded as a versatile toolbox for "production of molecular properties".

Keywords: organic synthesis, 1,3-dipolar cycloaddition, click chemistry


Wiadomości Chemiczne, 2005, 59, 583.
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ANOMERIC EFFECT

Andrzej Nowacki, Andrzej Wiśniewski

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


Conformational equilibrium of cyclohexane derivatives depends on the location of the substituents in carbocyclic ring. Equatorial location of non-hydrogen substituents dominate over axial one because in the latter case there exist unfavourable 1,3-diaxial interactions. The solvent effect on the equilibrium is well known. Diequatorial conformer of trans-1,2-dibromocyclohexane is favoured over the diaxial one in polar solvents, while diaxial conformer is favoured in non-polar solvents. Conformational equilibrium of cis-1,3-hexanediol is controlled by intramolecular hydrogen bond, whose strength depends on the solvent polarity (Fig. 3) [19].

Replacement of one or more methylene groups by oxygen atoms in carbocyclic ring changes conformational equilibrium of variously substituted tetrahydropyrans or dioxane derivatives as is shown in Figs. 5 and 6. Conformational equilibrium of α-substituted tetrahydropyran depends on the structure and chemical character of the substituent. Electron-withdrawing groups flavour axial orientation. This phenomenon is called endo-anomeric effect, (AE) [17] and is characteristic for compounds with C-X-C-Y structural fragment, where X is N, O or S and Y is F, Cl, Br, O, N or S. This effect is revealed in non-polar solvents, while the equatorial orientation of C-1-substituent is preferred in strongly polar solvents [14]. The effect is associated with shortening of the X-C-1 and elongation of the C-1-Y bonds (Fig. 11) [26]. Hyperconjugation of the non-bonding orbital of oxygen atom and antibonding σ*orbital of the C-1-Y bond is responsible for this effect [9-11, 23]. Gibss free energy of the anomeric effect decreases in the order: halogen atom > OR > SR > OH > NH2 > C. Conformational or/and anomeric equilibrium of sugars and its derivatives is controlled by anomeric effect and so called instability factors (IF). Non-bonded interactions between groups in the sugar ring, i.e. IF, are well known and exhaustively discussed in the literature [33-35].

In the molecules of glycosides and their derivatives apart from endo-anomeric effect, also exo-anomeric effect is present, which determines the spatial orientation of the aglycon in relation to the sugar ring [17]. The latter effect concerns both anomers and favours such an aglycon orientation in which the dihedral angle O-5-C-1-O-1 C is +sc (for α-D-anomer) and -sc for β-D-anomer. The above mentioned arrangement enables hyperconjugation of non-bonding sp3 orbital of O-1 (exo) atom with the antibonding orbital of O-5-C-1 bond. This effect is responsible for the spartial structure of some polysaccharides.

Nitrogen substituens (especially those with a positive charge) and carbon substituents are preferably located in the equatorial orientation due to the so called reverse anomeric effect (RAE) [18]. This effect is characteristic for N-(glycopyranosyl)pyridinium, -imidazolium and similar salt [32, 42, 43]. Some authors suggest that RAE does not exist and the equilibrium state of such compounds depends on the exo-anomeric or steric effects [45, 46-48].

Keywords: conformational equilibria, exo- and endo-anomeric effect, reverse anomeric effect


Wiadomości Chemiczne, 2005, 59, 613.
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ADSORPTION OF PHENOLS ON ACTIVATED CARBON

Andrzej Dąbrowski1, Przemysław Podkościelny1, Zbigniew Hubicki1, Mariusz Barczak1, Erich Robens2

1 Wydział Chemii, Uniwersytet Marii Curie-Skłodowskiej, 20-031 Lublin, Polska
2 Instytut Chemii Nieorganicznej i Analitycznej, Uniwersytet J. Gutenberga, Duesbergweg 10-14, D-55099 Mainz, Niemcy


Adsorption of phenolic compounds on activated carbons is considered based on survey of abundant literature on it. Phenols belong to a group of common environmental contaminants. Since they are highly toxic and, in general, not amenable to biological degradation, methods of treatment are continuously being modified and developed. Adsorption by activated carbons is the best and most frequently used method to remove phenols from waters. Numerous factors are known to have important influence on this phenomenon: type of carbon, carbon surface functionalities, pH value of the coexisting bulk liquid phase, oxygen availability, etc. In this review, we have tried to discuss the significance of the above-mentioned factors. The first chapter of the review deals with characterization of the activated carbon from the point of view of application for phenols uptake. The selection of precursors of activated carbon as well as generation of porosity and surface chemical composition are taken into account. Adsorption of phenolic compounds has been described critically, showing the development of investigations on the subject and presenting some of the most important results. A special attention is paid to the effect of surface functionalities and pH of solution. These two factors are considered together, because owing to the amphoteric character of a carbon surface its surface properties may be influenced by the pH value of the coexisting liquid bulk phase. The fundamental mechanisms of phenol adsorption have been emphasized i.e. "π-π interactions" and "donor-acceptor complex formation", taking into account the influence of the so-called "solvent effect". Energetic heterogeneity of activated carbons is presented on the basis of adsorption energy distribution functions, calculated by using algorithm based on a regularization method. Analysis of these functions provides significant comparative information about their heterogeneity. Problems associated with irreversible adsorption from aqueous solutions of phenols and their surface polymerization are reported in vast paragraph. We concluded that the presence of molecular oxygen and its amount has significant influence on the adsorption capacity of activated carbon for phenol and its derivatives. Oxidative coupling in the presence of molecular oxygen causes irreversible adsorption (chemisorption). Effects of different substituents of phenols are considered too. Bigger size and/or larger number of groups of an adsorbate lead to a higher heterogeneity for the same surface. It has been stressed that, neither of the substituent groups was involved directly in the interaction with the carbon surface, but they contribute to the electron-acceptor characteristics of the aromatic ring of the solute. The cheap precursors of activated carbons from the waste materials are also described in our review. Finally, some remarks dealing with application of novel adsorbents for phenols adsorption, such as activated carbon fibers are discussed.

Keywords: adsorption, phenolic compounds, activated carbon, heterogenous sorbents, energy distribution function, reversible and irreversible adsorption, environmental protection


Wiadomości Chemiczne, 2005, 59, 639.
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SEQUENTIAL EXTRACTION OF METALS FROM ENVIRONMENTAL SAMPLES

Jan Kalembkiewicz, Eleonaro Sočo

Katedra Chemii Nieorganicznej i Analitycznej, Wydział Chemiczny, Politechnika Rzeszowska, al. Powstańców Warszawy 6, 35-959 Rzeszów


The metals contribution in food chain: soil - plant - animal - man and influence of metals on the course of biochemical reactions in the environment depends among others on possibility of its transfer from sample to solutions. In practice mobility process of metals is investigated by performance of the sequential extraction of sample. The metals sequential extraction for a given sample depend among others on the type of sample, leaching reagent, conditions of the process, the initial condition of sample (environmental sample, air-dried sample) and chemical forms of metals presents in sample. Most often the studies evaluate the chemical fraction of metals in environmental sample as: exchangeable, carbonate, oxide, organic, sulfide and residue forms. Many procedures of sequential extraction of sample e.g. soil, bottom sediments and fly ash were described, which include group extraction of metals to solution.

Applied procedures of sequential extraction concern of group extraction of metals and doesn't selective for individual metals. Therefore, we have attempted to establish optimum conditions for researches of individual chemical fraction of metals in sample by sequential extraction method. Chemical fraction described as mobility in environmental conditions are frequently research in first and second step of sequential extraction. Next researches fractions of metals are mobile in environmental in specific conditions.

Among various methods of the sequential extraction, the Tessier [1-3], Rudd [4], BCR [5-8], Gatehouse [9], Kersten and Főrstner [10], Psenner [11] and Sposito [12] procedures are most often used for environmental samples. The procedures sequential extraction of environmental samples, defined metals fraction and list of researches metals in sample are shown in Table 1. Analysis of chemical fraction of metals depends on quantity of steps method, strong of reagents and conditions of researches.

Keywords: environmental samples, sequential extraction, metals


Wiadomości Chemiczne, 2005, 59, 697.
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THE APPLICATION OF QUERCETIN, MORIN AND THEIR SULFONIC DERIVATIVES IN THERAPY AND FOOD INDUSTRY

Maria Kopacz, Anna Kuźniar

Katedra Chemii Nieorganicznej i Analitycznej, Wydział Chemiczny, Politechnika Rzeszowska, al. Powstańców Warszawy 6, 35-959 Rzeszów


Flavonoids (derivatives of 2-phenylo-γ-benzopyrone) are a large group of biologically active plant products. As a common component of daily nutrition, flavonoids can modulate many biological processes. Therapeutic properties of flavonoids have been well known for many years. Originally, the object of interest was medicinal plants. The papers by Szent-Győrgy revealed that a lemon compound belonging to flavonoids - hesperidin has a synergic effect with Vitamin C and prevents scurvy [1].

Quercetin (3,5,7,3',4'-pentahydroxyflavone) and morin (3,5,7,2',4'-pentahydroxyflavone), Fig. 1, are the most widespread flavonoids. Due to their properties these compounds find application in teraphy as viral antigens, bactericide and antitumor agents [30, 31, 35-39].

Owing to a convenient position of oxygen in the 5C-OH and 4C=O as well as 3C-OH and 4C=O groups, morin and quercetin form chelate complexes with ions of p-, d- and f-electron metals. Some researchers think, that biological activity of flavonoids is connected with their complexation capacity. Therapeutic action can show both the molecule and its metabolite. The application of quercetin and morin is restricted due to their insolubility in water. Their sulfonic derivatives are well soluble in water and show biological activity as their mother compounds. Therefore, the latter can be more useful for therapy purposes.

Keywords: flavonoids, quercetin, morin, sulfonic derivatives, biological activity, food preservation


Wiadomości Chemiczne, 2005, 59, 723.
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Notatki Chaotyczne. LVIII. O PRAWYM I LEWYM

Ignacy Z. Siemion

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



Wiadomości Chemiczne, 2005, 59, ??.
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INSECT GONADOTROPIC PEPTIDE HORMONES

Mariola Kuczer, Danute Konopińska

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


Gonadotropic peptides are a new generation of peptide hormone regulators of methamorphosis and reproduction of insects. These substances have been isolated from ovarian, oviduct or brain of insects. The subject of this paper is a several insect gonadotropic peptides which:
         -stimulate ovarian growth,
         -modulate biosynthesis of trypsine,
         -speed up vitellogenesis,
         -stimulate ecdysteroid production,
         -inhibit serine proteases,
         -have other activities.
Basing on the literature data and results of our investigations their structure and biological properties are presented.


Wiadomości Chemiczne, 2005, 59, 755 .
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CAPILLARY ELECTROCHROMATOGRAPHY - THEORETICAL BASIS AND ITS APPLICATIONS

Irena Malinowska1, Marcin Drozdowski2, Jacek Bojarski2

1Zakład Chromatografii Planarnej, Wydział Chemii UMCS, Plac M. Curie-Skłodowskiej 3/243, 20-031 Lublin,
2Katedra Chemii Organicznej Collegium Medicum UJ, ul. Medyczna 9, 30-688 Kraków


In this article the theoretical basis of capillary electrochromatography are presented, as well as some of its analytical applications. The historical background of this analytical method is briefly outlined. The nature of Helmholtz and Stern double layer at the phase boundary resulting in the electroosmotic flow (EOF) and the equations describing its velocity are shortly discussed. From these equations it follows that EOF depends on the properties of liquid phase (a ratio of dielectric constant to viscosity), the electric field intensity and the electric double layer (ς potential) but does not depend on the diameter of particles of column or capillary packing. The relationship between EOF and efficiency of the chromatographic system is discussed and some advantages and disadvantages of electrochromatography are mentioned.

The columns (capillaries) used in electrochromatography (packed, open tubular and monolytic) are described.

The applications of capillary electrochromatography described here encompass enantioselective analysis and separation of mixtures of analytes. The examples of enantioseparations deal mainly with drugs, whereas electrochromatographic separations of mixtures are exemplified by amino acids, peptides, proteins and some groups of drugs (barbiturates and benzodiazepines).

It is concluded that electrochromatography, although relatively .young. analytical method, found important applications and is in the phase of constant development.


Wiadomości Chemiczne, 2005, 59, 771.
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SODIUM WATER GLASSES. PART I. SYNTHESIS AND APPLICATIONS

Wiesław Kożlak

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


In this paper a review of the technology of production and applications of water glasses was presented as well as their definition and the n methods of their identification and description. Mainly sodium water glasses were presented because they have much wider area of applications than other types of alkaline silicates. It was shown that many scientific centers in the word are developing technologies of production of silicates and their water solutions using new ideas as well as by modifying the technologies earlier proven effective.

Among the range of applications of sodium water glasses the problems of water purification (lowering water hardness), anti-corrosion protection of water pipelines were emphasized along with the characteristics of silicate inhibitors and the attempt to elucidate the mechanism of their anti-corrosion action not only on steel but also on other materials.

The uses of sodium silicates as packing and form making masses as well as other applications of water glasses were also discussed.

For the attempt to elucidate the action mechanism of silicates, the second part of this paper was prepared in which the methods of determination of molecular composition of sodium silicates water solutions were presented.


Wiadomości Chemiczne, 2005, 59, 791.
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IN THE SEARCH FOR PHYSICOCHEMICAL BASIS OF HOMEOPATHY

Jacek Tyczkowski, Ewa Tyczkowska-Sieroń*

Wydział Inżynierii Procesowej i Ochrony Środowiska, Politechnika Łódzka, ul. Wólczańska 112, 93-005 Łódź
*Katedra Biologii i Genetyki Medycznej, Uniwersytet Medyczny w Łodzi, Plac gen. J. Hallera 1, 90-647 Łódź


Homeopathy is an alternative medicine system that uses ultra-low doses of substances derived from plants, minerals, or animals for the purpose of stimulating the natural healing response of the body. There are two central tenets, on which homeopathy is based: the law of similars and potentization (dilution and shaking) [1].

Despite conventional science.s unwillingness to grant homeopathy a serious platform, it is difficult to ignore a subject that has survived 200 years of scientific skepticism and is more and more popular alternative system of medicine [2-4]. Two main questions, however, accompany the whole history of this complementary method: are homeopathic remedies really effective? And if it is true: what is a mechanism of the homeopathic effects?

Homeopathy remedies are prepared in a very specific manner. The original substance, called mother tincture, is progressively diluted in a solvent (water, ethanol) and .potentized. by violent shaking between each dilution. It is obvious that after a definite number of dilutions the obtained solution is statistically unlikely to contain a single molecule of the original compound. Such solutions are called ultra-highly diluted (UHD) solutions. Looking for a scientific basis of homeopathy, it is very important to distinguish between remedies containing a low but real dose of the original substance, for which their efficacy is within the limits of what is today.s knowledge, and remedies without molecules of the original compounds (UHD solutions), of which effects (if so) are beyond our understanding.

Research on the UHD solutions can roughly be classified into three topics [11]. The first concerns clinical investigations on efficacy of homeopathic remedies and their comparison with placebo. Although a lot of trials and meta-analysis have been performed, the general conclusion is totally ambiguous [35-45] (Fig. 1). The latest reports [304], however, strongly support the notion that the clinical effects of homeopathy are placebo effects. The second topic includes laboratory research on the biological effects, sometimes called preclinical research. The best-known and the most controversial at the same time results were published in 1988 by Benveniste [47] (Fig. 2), a once highly respected immunologist, that advocated the existence of biological effects of UHD solutions. Since then numerous experiments have been carried out on laboratory biological systems [71] (e.g. Fig. 3). Unfortunately, these studies, just as in the case of clinical research, are far from giving incontrovertible evidence for the UHD effects. Finally, the third research topic, which makes the main subject of this paper, is focused on physical, chemical and physicochemical investigations of the UHD solutions. In general, all these investigations are based on the water memory hypothesis [48-50] and concentrate on the search for physicochemical differences between the UHD solutions and their "pure" solvents.

The authors of this paper present herein all published more significant results concerning physicochemical studies carried out on the UHD solutions and undertake an attempt to answer a question, namely whether there is any evidence, on the basis of these results, that can explicitly prove the water memory effect. The results are collected in a few sections according to physicochemical phenomena. The first of these sections (Section 4.2) is devoted to UV-VIS spectroscopy, and investigations of photoabsorption [97-101], photoluminescence [106.109] and thermoluminescence [111-114] are discussed. Examples of these results are shown in Figs. 4-7. Than the studies of "pure" water and the UHD solutions by IR [115-128] (Figs. 8,9) and Raman [109, 116, 125, 129-143] (Fig. 10) spectroscopies are presented. The next section includes findings that are related to NMR spectroscopy. NMR has turned out to be a very useful technique to study of dynamic properties of liquid water [145-147]. Although the earlier tests showed evident differences between various UHD solutions and their solvents [148-155, 158] (Fig. 11), the recent investigations are not so optimistic giving negative replications [159, 160, 162] (Fig. 12). It indicates that the previous NMR results should be thoroughly revisited. Similarly, reanalysis of the results concerning thermodynamic study, described in the Section 4.5, is also desirable. These investigations were carried out only by one research team from University of Naples [166-169] and it has not been replicated by other laboratories as yet. The problem consists in measurements of the heats of mixing of acid or basic solutions with various UHD solutions (Fig. 13). In this paper it is suggested that these results, which are connected by the researchers from Naples with the water memory effect, can be explained another, more .conventional. way [170-172].

A large proportion of the work is devoted to electrical properties of the UHD solutions and its comparison to pure water and conventional solutions. In this section (Section 4.6), measurements of the electrical conductivity and capacitance [126, 183-193] (Figs. 14,15), electrical breakdowns [196-199], corona discharges [202-204] (Fig. 16), and electrochemical processes [205-210] (Fig. 17) are discussed. It is shown that also in this case we can propose the explanation of the observed effects without invoking the water memory hypothesis. In the last part of the sections, in which we can familiarize with physicochemical investigations on the UHD solutions, very questionable measurements of molecular signals and their transmission by electromagnetic means are reported [213-223, 228-230] (Fig. 18). This issue is closely connected with "digital biology" - a new controversial field of science [212].

Summarizing the mentioned above results of physicochemical investigations we can come to a conclusion that without any doubt in many instances the differences in properties between UHD solutions and their solvents exist. In the light of this fact the crucial problem emerges: is it possible to explain these differences by "conventional" causes or we have to create a new idea that will transform the face of the science? In Sec. 5 we collect both hypotheses based on well-known phenomena (Sec. 5.1), for example ion extraction from the glass during shaking [109, 233, 234], gas dissolving [95, 170-172, 189, 227, 235-240], native impurities of solvents [162, 241-250] (Tables 1 and 2, Fig. 19), mechano-catalytic processes [253, 254], heterogeneity of solutions [255-260], and new but disputed hypotheses (Sec. 5.2) originated from the general conception of water memory [19, 48-50, 74, 158, 252, 261-267, 279-292]. It is shown in the paper that the latter hypotheses do not hold up to criticism provided by the modern established knowledge [77, 78, 80, 83, 117, 268-278]. It is also concluded that today there is no reason to construct groundbreaking theories and the observed phenomena can be explained by "conventional" way. It is very important to remember the following Aristotle's thought: if we want to accept any truth as the scientific knowledge, it must originate from other truths.


Wiadomości Chemiczne, 2005, 59, 807.
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Notatki Chaotyczne. LIX. Cagliostro Démasqué à Varsovie

Ignacy Z. Siemion

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



Wiadomości Chemiczne, 2005, 59, 865.
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TOOLS FOR COMBINATORIAL CHEMISTRY. PART 3. REACTION IN SOLID PHASE ORGANIC SYNTHESIS

Ryszard Łaźny, Mołgorzata Lipińska, Michał Sienkiewicz

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


Solid Phase Organic Synthesis (SPOS) is a dynamically growing branch of organic synthesis encompusing methods for synthesis of both small molecules and oligomers on solid supports. Synthetically useful organic reactions of substrates immobilized on solid supports constitute a central part of the methodology of solid phase synthesis. This review article presents a representative and fairly comprehensive overview of reactions of supported substrates published till January 2005. The reactions are classified in synthetic terms into functional group interconvertions (FGI, according to type of functional group reacting and prepared) and C-C bond forming reactions (according to reaction type; usually name reaction). In particular preparations of halogens, alcohols, ethers, thiols, aldehydes, ketones, acids, esters, amides, phosphines, amines, poliamines, peptides, peptoids, oligonucleotides, and oligosaccharides is covered. Oxidation reactions of alcohols, aldehydes and ketones as well as reduction reactions of aldehydes, ketones, esters, acids, nitro and nitroso compounds are also presented. Only the selected reactions used for preparation of oligonucleotides, oligosaccharides, and polypeptides are covered due to the large volume of literature on this topic. The important C-C bond forming reactions such as Mannich, Michael, aldol, Heck, Suzuki, Stille, Sonogashira, Wittig, Horner-Wadsworth- Emmons, metathesis, carbonyl compound alkylation and acylation reactions are illustrated with examples. Moreover the multicomponent reactions such as Ugi reaction, Hantzsch reaction and Baylis-Hillman reaction are also included in the review.

The literature review shows a spectrum of synthetic organic reactions which can be performed on the immobilized substrates and suggests that in principle every reaction could be performed on solid phase. However the literature review indicates that reactions of polar organometallic reagents, radical reactions, and enantioselective reactions of achiral immobilized substrates are rather rarely used in SPOS.


Wiadomości Chemiczne, 2005, 59, 881.
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PEGYLATION - A METHOD OF MODIFICATION OF PROPERTIES OF POLYPEPTIDIC DRUGS AND BIOLOGICALLY ACTIVE COMPOUNDS

Jakub Ferenc, Katarzyna Kieć-Kononowicz

Katedra Technologii i Biotechnologii Środków Leczniczych Collegium Medicum Uniwersytetu Jagiellońskiego, ul. Medyczna 9, 30-688 Kraków


This review attempts to briefly summarize the recent developments in the area of PEGylation. Pegylation, the process by which polyethylene glycol chains are attached to as well protein and peptide drugs as low molecular weight molecules is used to modify the properties of drugs, biologically active structures. It has influence on pharmacokinetic and pharmacodynamic properties, stability and immunogenicity of structures. The advantages and drawbacks of such modifications were discussed. Pegylation of polypeptide and protein structures as well as small molecules was presented. Pegylation process was divided in two groups: pegylation of the first and second generation. Both processess were presented. Examples of pegylated drugs (Adagen, Oncaspar - first generation; PEG-intron, Pegasys, Somavert, Neulasta - second generation) already introduced into the market were shortly presented, structures being under investigation were mentioned.


Wiadomości Chemiczne, 2005, 59, 953.
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PLANT SIGNALING PEPTIDES

Agata Bachyrycz, Danuta Konopińska, Katarzyna Szymanowska

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


Subject of the paper are a signaling plant peptides. There are peptides of a new generation, regulating processes of growth, differentiation and other physiological plant function.

Here will presented the literature data and results of our studies. Especially the results of structure/function relationship studies will presented for systemin and phytosulfokine- α.


Wiadomości Chemiczne, 2005, 59, 981.
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BIOINDICATORS IN ENVIRONMENTAL POLLUTION MONITORING - A REVIEW

Krystyna Srogi

Instytut Chemicznej Przeróbki Wegla, ul. Zamkowa 1, 41-803 Zabrze


The aim of the study was a review using bioindicators in biomonitoring. As it well known, bioindicative methods are commonly used in the evaluation of environmental purity levels. Various types of plants are used as popular indicators of contamination, form mosses and lichens to trees or plants. Also, the monitor metal pollutions the following were suggested as bioindicators: pine bark, bacteria, fungi, grasses, ferns, algae, animals or human hair and laying hen feathers. It should be noted that monitoring with mosses as well as other bioindicators/biomonitors provides lowcost information on the nature and quantity of pollutant deposition and since the accumulation of elements by mosses is high, this creates ideal conditions for analysis and overcomes problem related to analytical sensitivities.


Wiadomości Chemiczne, 2005, 59, 1001.
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Notatki Chaotyczne. LX. O Potrzebie Luzu

Ignacy Z. Siemion

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



Wiadomości Chemiczne, 2005, 59, 1023.
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