Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "Chemical synthesis" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-4 z 4
    Tytuł:
    Peptydoglikan : budowa, rola biologiczna oraz synteza
    Peptidoglycan : structure, biological activity and chemical synthesis
    Autorzy:
    Samaszko-Fiertek, J.
    Dmochowska, B.
    Madaj, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/171802.pdf
    Data publikacji:
    2015
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    peptydoglikan
    synteza chemiczna
    biosynteza
    aktywność biologiczna
    peptidoglycan
    chemical synthesis
    biosynthesis
    biological activity
    Opis:
    The most important component of bacterial cell walls especially Gram-positive bacteria is peptidoglycan, called also murein, PGN. The first time this synonym was used in 1964 by Weidel and Pelzer [1]. Peptidoglycan is present in the outer layer of the cytoplasmic membrane and its structure. The structure of peptidoglycan depends on the bacteria strain. It is estimated that in Gram-negative bacteria, it occupies only about 10–20% of the total area of the cell wall, when in Gram-positive bacteria it is 50 and up to 90% of all space. Problems with isolation with high purity of biological material shows the need for developing techniques for chemical synthesis of peptidoglycan fragments and their analogs. In past few years there has been a growing interest within the synthesis of compounds glycoprotein (glycopeptides, peptidoglycan, etc.). As a basis for the construction of cell walls of many bacteria. Despite intensive research and gain significant knowledge of the physical and biological, chemical synthesis or biosynthesis (Fig. 5 and 6) of peptidoglycan, not so far failed to unambiguously determine its three-dimensional structure. The works of Kelman and Rogers [15] and Dimitriev [20] nearer picture of its structure. However, the time to develop in vivo visualization of cell structure it will be difficult to identify correctly peptidoglycan three-dimensional structure. Due to the important biological roles of murein, many research centers have taken to attempt their chemical synthesis. For biological research began to use chemically synthesized peptidoglycan fragments which guaranteed both uniform and a certain structure. An important roles in the development of methods of chemical synthesis of peptidoglycan had H. Chowdhury work, Fig. 8 [35], Hesek, Fig. 9 and 10 [36, 37], Dziarskiego [38] and Boneca [39] and Inamury [34, 40].
    Źródło:
    Wiadomości Chemiczne; 2015, 69, 7-8; 513-540
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Metody chemicznej ligacji w syntezie peptydów i białek. Część 2
    Chemical ligation methods in the synthesis of peptides and proteins. Part 2
    Autorzy:
    Jędrzejewska, K.
    Kropidłowska, M.
    Wieczerzak, E.
    Powiązania:
    https://bibliotekanauki.pl/articles/172242.pdf
    Data publikacji:
    2017
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    natywna chemiczna ligacja
    synteza peptydów
    tioester
    native chemical ligation
    peptide synthesis
    thioester
    Opis:
    Proteins are synthesized only by living organisms. Today, we are able to receive them by recombinant protein expression in bacterial cells. This technique is very useful and gives satisfactory amount of desirable material but it precludes the possibility of introduction of some chemical modifications that are often obligatory. For this reason, chemical synthesis of longer peptide chains is still important and is the object of scientists attention. Over the last century, notion of peptide synthesis took a new meaning. Nowadays, we know a number of innovative methods and also automated devices which help us to make progress in this area. Nevertheless, the synthesis of longer, more complicated peptide chains and proteins still constitutes a problem. Native chemical ligation (NCL) has facilitated the synthesis of numerous complex peptide and protein targets. Expansion of ligation techniques has allowed the entry of peptides into the world of therapeutic drugs [1]. NCL reactions are carried out in aqueous solution and give good yields. Due to mild conditions, NCL overcomes racemic and solubility problems encountered in classical peptide synthesis using protected fragments. The challenge is to synthesize the C-terminal thioester-containing peptide necessary for the transesterification reaction, which is the first step of linking the peptide fragments [2]. In this review we discuss the evolution, advantages and potential applications of chemical ligation reactions. In the first part of this article we described the utility of native chemical ligation approach to non-cysteine containing peptides. This part details a number of important approaches to the synthesis of peptides bearing a C-terminal thioester. Contemporary applications of these techniques to the total chemical synthesis of proteins are also presented.
    Źródło:
    Wiadomości Chemiczne; 2017, 71, 9-10; 747-761
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Metody syntezy i właściwości fizykochemiczne 2,4,6,8,10,12-heksanitro-2,4,6,8,10,12-heksaazaizowurcytanu (HNIW)
    The methods of synthesis and physicochemical properties of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (HNIW)
    Autorzy:
    Borkowski, J.
    Czerwińska, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/171958.pdf
    Data publikacji:
    2013
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    Cl-20
    HNIW
    synteza
    właściwości chemiczne
    właściwości wybuchowe
    CL-20
    synthesis
    chemical properties
    explosive properties
    Opis:
    Explosives have a very rich history of its creation. This history dates back to the ninth century, when the Chinese invented a black powder. In the end of the twentieth century, the first nitroamine polycyclic cage structure was obtained. The representative of this group is 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaizowurtzitane (HNIW, Cl-20). HNIW has recently been the subject of an interest as one of the strongest explosive material. As nitroamine, HNIW is compared to the other energetic materials: RDX i HMX [1, 2]. Researchers [5, 6] showed, that it is possible to replace a variety of typical explosives by HNIW and thanks to that obtain compositions with higher densities, heat of explosion and higher velocity of detonation. In the published papers [7-13, 16] there were presented six polymorphs of HNIW: αβγδε with specific stabilities and structural characteristics. Unfortunately, there is no a direct method of obtaining HNIW. There are at least four steps needed to obtain HNIW. The first step is the synthesis of HBIW [20-22]. The next one is debenzylation reaction of HBIW [20-29] in order to remove the benzyl groups. The third step is removal of the two other benzyl groups and replace them by nitroso, formyl or acetyl groups [20, 24, 30, 32]. In the final step there is a nitration of HNIW precursors [31-37]. The HNIW seems to be a promising explosive and it can replace other currently used energetic materials. However, using HNIW is limited due to the complicated and expensive technology of its production. Therefore, research groups carried out new syntheses of HNIW to eliminated these problem. In this article, review of the literature on the physicochemical properties and synthetic methods for HNIW were presented. The basic physical and explosive parameters of HNIW were summarized. The spatial structure was presented and polymorphs of HNIW were characterized. The methods for obtaining HNIW and intermediate products needed for its preparation were described. The methods of preparation of different HNIW polymorphs were also given.
    Źródło:
    Wiadomości Chemiczne; 2013, 67, 1-2; 93-109
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Metody chemicznej ligacji w syntezie peptydów i białek. Część 1
    Chemical ligation methods in the synthesis of peptides and proteins. Part 1
    Autorzy:
    Kropidłowska, M.
    Jędrzejewska, K.
    Wieczerzak, E.
    Powiązania:
    https://bibliotekanauki.pl/articles/171570.pdf
    Data publikacji:
    2017
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    natywna chemiczna ligacja
    NCL
    kinetycznie kontrolowana ligacja
    KCL
    synteza peptydów
    native chemical ligation
    kinetically controlled ligation
    peptide synthesis
    Opis:
    Proteins are biological macromolecules affecting very important functions in the body. They are involved in many biochemical processes. They can perform catalytic functions acting as enzymes. They also participate in the transport of many small molecules and ions – for example one molecule of hemoglobin carries four molecules of oxygen. In addition, proteins serve as antibodies and are involved in transmission of nerve impulses as receptor proteins. Because peptides and proteins perform so important functions, to study them it is essential to obtain these compounds in the greatest possible amounts. The compounds can be obtained generally by three main methods: • by isolation of the native peptides and proteins • by expression in microorganisms • by chemical synthesis. Each of the above methods has its advantages and disadvantages, but only the chemical synthesis gives the possibility to introduce modifications to the structure of the resulting protein, such as the insertion of new functional groups, to give the product in the final form and with satisfactory yield. In this review we present the application of chemical ligation methods in the synthesis of peptides and proteins. We describe in details mechanism of native chemical ligation method and the conditions necessary to carry the reaction [1]. The synthesis of long polypeptide chains by kinetically controlled ligation (KCL) is also depicted [2]. This part of the paper also details a number of approaches to noncysteine containing peptides by chemical ligation methods.
    Źródło:
    Wiadomości Chemiczne; 2017, 71, 9-10; 727-746
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-4 z 4

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies