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    Wyświetlanie 1-11 z 11
    Tytuł:
    C-nukleozydy : synteza i aktywność biologiczna
    C-nucleosides : synthesis and biological activity
    Autorzy:
    Grabkowska-Drużyc, M.
    Piotrowska, D. G.
    Powiązania:
    https://bibliotekanauki.pl/articles/172646.pdf
    Data publikacji:
    2015
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    analogi nukleozydów
    C-nukleozydy
    homo-C-nukleozydy
    heterocykliczne C-nukleozydy
    acykliczne C-nukleozydy
    aktywność biologiczna
    nucleoside analogues
    C-nucleosides
    homo-C-nucleosides
    heterocyclic C-nucleosides
    acyclic C-nucleosides
    biological activity
    Opis:
    Studies on synthesis and biological activity of modified nucleoside and nucleotide analogues have been an active field of research in medicinal chemistry for years [1, 2]. High biological activity of naturally occurring C-nucleosides, for example showdomycin 5, formycins A 41 and B 42 motivated many research groups to study their analogues and structurally similar compounds. Furthermore, since C-nucleosides lack N-glycosidic bond they are more resistant to enzymatic hydrolysis [3]. This review collects selected methods of synthesis of C-nucleoside analogues which were analyzed to point out the most interesting and inspiring synthetic strategies, in many cases based on contemporary achievements. These strategies first of all take advantage of the formation of the C–C bond between the anomeric carbon atom of the sugar or pseudosugar moieties and the carbon atom of the modified nucleobases. Less common approach relies on the de novo construction of heterocyclic rings employed as nucleobase substitutes. Though years many new compounds sometimes of significant structural complexity have been obtained and characterized to find several examples endowed with high antiviral and cytostatic activity. The biological activity of the C-nucleoside analogues screened so far encourages us to continue a search for new potential drugs within compounds equipped with this attractive structural motif.
    Źródło:
    Wiadomości Chemiczne; 2015, 69, 3-4; 197-225
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Izoksazolidynowe analogi nukleozydów
    Isoxazolidine analogues of nucleosides
    Autorzy:
    Kokosza, K.
    Piotrowska, D. G.
    Powiązania:
    https://bibliotekanauki.pl/articles/171674.pdf
    Data publikacji:
    2012
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    1,3-dipolarna cykloaddycja
    nitrony
    izoksazolidyny
    analogi nukleozydów
    nukleozasady
    C-nukleozydy
    homonukleozydy
    nukleozydy
    fosfonylowane nukleozydy
    psiko-nukleozydy
    aktywność przeciwwirusowa
    aktywność przeciwnowotworowa
    1,3-dipolar cycloaddition
    nitrones
    isoxazolidines
    nucleoside analogues
    nucleobases
    C-nucleosides
    homonucleosides
    nucleosides
    phosphonylated nucleosides
    psico-nucleosides
    antiviral activity
    anticancer activity
    Opis:
    Compounds having isoxazolidine moiety are of special interest since they show a broad spectrum of biological activity, including anticancer [1–5], antiviral [6], antibacterial [7–9] and antifungal activities [9–12]. Extensive studies on isoxazolidine moiety containing compounds resulted in discovery of several potentially antiviral and anticancer drugs (e.g. pyridemine-A 1 [2, 3], as well as isoxazolidines substituted with thymine and 5-fluorouracil 52a (AdT) [38–40] and 59 [(–)-AdFU] [41–43], respectively). In this review the most spectacular examples of the synthesis of isoxazolidine analogues of nucleosides are discussed and their biological activity is emphasized.
    Źródło:
    Wiadomości Chemiczne; 2012, 66, 11-12; 1041-1070
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Using capillary electrophoresis to study methylation effect on RNA-peptide interaction.
    Autorzy:
    Mucha, Piotr
    Szyk, Agnieszka
    Rekowski, Piotr
    Agris, Paul
    Powiązania:
    https://bibliotekanauki.pl/articles/1043465.pdf
    Data publikacji:
    2003
    Wydawca:
    Polskie Towarzystwo Biochemiczne
    Tematy:
    methylated nucleosides
    methylation
    arginine methylation
    RN-peptide interaction
    capillary electrophoresis
    Opis:
    Methylation of RNA and proteins is one of a broad spectrum of post-transcriptional/translational mechanisms of gene expression regulation. Its functional signification is only beginning to be understood. A sensitive capillary electrophoresis mobility shift assay (CEMSA) for qualitative study of the methylation effect on biomolecules interaction is presented. Two RNA-peptide systems were chosen for the study. The first one consists of a 17-nucleotide analogue (+27-+43) of the yeast tRNAPhe anticodon stem and loop domain (ASLPhe) containing three of the five naturally occurring modifications (2'-O-methylcytidine (Cm32), 2'-O-methylguanine (Gm34) and 5-methylcytidine (m5C40)) (ASLPhe-Cm32,Gm34,m5C40) and a 15-amino-acid peptide (named tF2 : Ser1-Ile-Ser-Pro-Trp5-Gly-Phe-Ser-Gly-Leu10-Leu- Arg-Trp-Ser-Tyr15) selected from a random phage display library (RPL). A peptide-concentration-dependent formation of an RNA-peptide complex was clearly observable by CEMSA. In the presence of the peptide the capillary electrophoresis (CE) peak for triply methylated ASLPhe shifted from 18.16 to 20.90 min. Formation of the complex was not observed when an unmethylated version of ASLPhe was used. The second system studied consisted of the (+18)-(+44) fragment of the trans-activation response element of human immunodeficiency virus type 1 (TAR RNA HIV-1) and a 9-amino-acid peptide of the trans-activator of transcription protein (Tat HIV-1) Tat(49-57)-NH2 (named Tat1 : Arg49-Lys-Lys-Arg52-Arg-Gln-Arg-Arg- Arg57-NH2). In the presence of Tat(49-57)-NH2 a significant shift of migration time of TAR from 18.66 min to 20.12 min was observed. Methylation of a residue Arg52→Arg(Me)2, crucial for TAR binding, strongly disrupted formation of the complex. Only at a high micromolar peptide concentration a poorly shaped, broad peak of the complex was observed. CE was found to be an efficient and sensitive method for the analysis of methylation effects on interaction of biomolecules.
    Źródło:
    Acta Biochimica Polonica; 2003, 50, 3; 857-864
    0001-527X
    Pojawia się w:
    Acta Biochimica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Chromatograficzna analiza związków budujących kwasy nukleinowe
    Chromatographic analysis of nucleic acids constituents
    Autorzy:
    Studzińska, S.
    Rola, R.
    Łobodziński, F.
    Krzemińska, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/172180.pdf
    Data publikacji:
    2016
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    nukleozydy
    nukleotydy
    oligonukleotydy
    chromatografia cieczowa
    czułość
    selektywność
    nucleosides
    nucleotides
    oligonucleotides
    liquid chromatography
    sensitivity
    selectivity
    Opis:
    Understanding the characteristics, role and structure of nucleic acids allowed to answer questions about the disease processes. Today, nucleic acids and their constituents are tools, which are used by molecular biology in medicine and biotechnology. Antisense and gene therapy are intensively developing methods for possible treating or preventing disease. They use short fragments of DNA or RNA - oligonucleotides to silence the genes expression. They are not the only ones that allow analytical chemists to obtain information about the state of our body. Determination of modified nucleoside allows detection of cancer, while analysis of nucleotides allows the estimation of strengthening the immune system. There is a great need of sensitive, selective and precise methods of separation of nucleosides, nucleotides and oligonucleotides and their qualitative and quantitative analysis. Consequently liquid chromatography (LC) is the most commonly used for analysis of nucleic acid constituents. The most widely used modes of LC include Ion Exchange Chromatography (IEC) and Reversed Phase High Performance Liquid Chromatography (RP HPLC). Both techniques have their advantages and disadvantages in the analysis of nucleosides, nucleotides and oligonucleotides. In the case of IEC it is necessary to use high concentrations of the salt in the mobile phase or concentration gradients, which considerably limits the possibility of using MS detection. RP HPLC can be coupled with MS detection but only when volatile salts are mobile phase components. On the other hand there is a significant problem is the lack of sufficient selectivity for the most polar nucleosides and nucleotides. RP HPLC MS is still most often used in the determination of nucleosides and nucleotides, due to its high sensitivity and a comprehensive qualitative analysis. Another system used for the HPLC analysis of oligonucleotides is Ion Pair Reversed Phase High Performance Liquid Chromatography (IP RP HPLC). These compounds can not be analyzed by RP HPLC due to their high polarity. The advantage of IP RP HPLC is selectivity, achieved by a suitable choice of mobile phase composition and the possibility of using MS. A disadvantage of IP RP HPLC in the analysis of oligonucleotides is however lower sensitivity compared to RP HPLC. During the last few years Hydrophilic Interaction Liquid Chromatography (HILIC) was applied for the separation of mixtures of nucleosides, nucleotides, oligonucleotides extracted from a biological or food samples. The presented results demonstrate the usefulness of this method, however, the resolving power is limited due to the asymmetric peak shape. On the other hand proper selection of the mobile and stationary phase can lead to a high selectivity in the analysis of the most polar nucleosides, nucleotides and oligonucleotides, which can not be separated by RP HPLC.
    Źródło:
    Wiadomości Chemiczne; 2016, 70, 9-10; 633-656
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Rola sygnalizacji purynergicznej i cytokin w indukcji procesów zapalnych w udarze niedokrwiennym mózgu
    Role of purinergic signalling and cytokines in the ischaemic stroke
    Autorzy:
    Cieślak, Marek
    Powiązania:
    https://bibliotekanauki.pl/articles/1057753.pdf
    Data publikacji:
    2012
    Wydawca:
    Medical Communications
    Tematy:
    nukleotydy
    nukleozydy
    cytokiny
    receptory purynergiczne
    udar niedokrwienny mózgu
    nucleotides
    nucleosides
    cytokines
    purinergic receptors
    ischaemic stroke
    Opis:
    Inflammation plays an important role in the aetiology of various diseases of the central nervous system including the stroke. Accumulating evidence indicates that inflammation in the central nervous system is controlled by purinergic signalling. The mediators of purinergic signalling are extracellular nucleotides (e.g. ATP, ADP, UTP and UDP) and adenosine that act via activation of P2 and P1 purinergic receptors, respectively. The activation of P2 and P1 receptors is regulated by the enzymes ectonucleotidases that hydrolyse either extracellular nucleotides or adenosine. This review focuses on the role of purinergic signalling in the ischaemic stroke. We and others have demonstrated the presence of nucleotides and adenosine in the cerebrospinal fluid. We have also shown that the concentration of ATP and other nucleotides is increased in cerebrospinal fluid of patients with ischaemic stroke. Evidence suggests that the activation of P2 and P1 recep-tors have an opposite role in the ischaemic stroke, i.e. while the nucleoside adenosine exert neuroprotective effects, nucleotides generally promote the proinflammatory and apoptotic responses. P2X7, P2Y2, P2Y6, P2Y11 and P2Y12 are proposed to be involved in the central nervous system inflammation as they are expressed in the brain and their activation is known to control the key inflammatory processes such as release of inflammatory mediators (e.g. cytokines, NO), migration of leukocytes, phagocytosis, apoptosis and thrombosis. The activation of P2 receptors can also increase the release of excitatory neurotransmitters that further exacerbate the inflammatory response. Three cytokines whose release is controlled by P2 receptors have a major role in the ischaemic stroke, namely tumour necrosis factor alpha (TNF-α), interleukin 1 (IL-1) and interleukin 6 (IL-6). By promoting inflammation and thrombosis, these proinflammatory cytokines contribute to the increase in lesion size and thus functional impairment of the affected tissue. Cytokines as well as extracellular nucleotides are involved in leukocyte migration to lesions. By their adherence to endothelium, leukocytes impair cerebral blood circulation and thus exacerbate damage to the brain. The hydrolysis of nucleotides to adenosine by the ectonucleotidases leads to deactivation of proinflammatory responses. Similar effect can also be obtained with P2X7 and IL-1 receptor antagonists that are presently under clinical development and investigation.
    Wyniki badań opublikowanych w ostatnich latach wskazują, że indukcja stanów zapalnych w ośrodkowym układzie nerwowym może stanowić podstawę patofizjologiczną wielu chorób, w tym udaru niedokrwiennego mózgu. Istotną rolę w tych procesach przypisuje się sygnalizacji purynergicznej i cytokinom. Receptory purynergiczne P1 i P2 oraz enzymy uczestniczące w degradacji nukleotydów są szeroko rozpowszechnione na komórkach ośrodkowego układu nerwowego. Puryny i pirymidyny wykazują dwojakie działanie w udarze niedokrwiennym mózgu: pozytywne (neuroprotekcyjne) nukleozydów oraz negatywne (prozapalne i proapoptotyczne) nukleotydów. W przebiegu udaru niedokrwiennego mózgu udowodniono udział w indukcji procesów zapalnych trzech cytokin: czynnika martwicy nowotworów α (TNF-α), interleukiny 1 (IL-1) i interleukiny 6 (IL-6). Cytokiny prozapalne wywołują procesy zapalne i prozakrzepowe, przez co zwiększają obszar zawału, a w konsekwencji stopień deficytu neurologicznego. Cytokiny i ATP sprzyjają migracji leukocytów do miejsca niedokrwienia mózgu, natomiast adenozyna działa przeciwstawnie. Leukocyty, przylegając do śródbłonka, upośledzają przepływ mózgowy krwi, w wyniku czego nasilają uszkodzenie tkanki nerwowej. Na uwalnianie cytokin prozapalnych, głównie interleukiny 1β, wpływa aktywacja receptora P2X7. Przypuszcza się, że w procesach zapalnych ośrodkowego układu nerwowego mogą uczestniczyć także receptory: P2Y2, P2Y6, P2Y11, P2Y12. Wydaje się, że degradacja nukleotydów z powstaniem adenozyny może być skutecznym sposobem obniżenia stężenia w przestrzeni pozakomórkowej nukleotydów, jak również cytokin prozapalnych i wygaszania procesów zapalnych. Inną metodą osłabienia intensywności procesów zapalnych jest zastosowanie antagonistów receptora P2X7 oraz inhibitora receptora IL-1 (IL-1Ra). Obecnie prowadzone są badania zarówno nad potencjalnymi antagonistami receptora P2X7, jak i inhibitorem receptora IL-1 (IL-1Ra).
    Źródło:
    Aktualności Neurologiczne; 2012, 12, 4; 205-214
    1641-9227
    2451-0696
    Pojawia się w:
    Aktualności Neurologiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Aktywność biologiczna modyfikowanych nukleozydów. Część 3
    Biological activity of modified nucleosides. Part 3
    Autorzy:
    Szlenkier, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/171517.pdf
    Data publikacji:
    2018
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    nukleozydy modyfikowane
    aktywność biologiczna
    cele molekularne
    mechanizm działania
    modified nucleosides
    biological activity
    molecular targets
    mechanism of action
    Opis:
    Part III of the review devoted to biological activities of nucleoside derivatives presents a further description of analogues modified in the sugar residue with particular focus on those with altered configuration in the 2’ or 3’ position, e.g. cytarabine – an old anticancer chemotherapy agent used to treat acute myeloid leukemia, acute lymphoblastic leukemia, and non-Hodgkin’s lymphomas; fludarabine – derivative of vidarabine used as a drug in the treatment of chronic lymphocytic leukemia, and non-Hodgkin lymphomas; clofarabine – approved by the FDA in 2004, a new-generation second-line drug for recurrent acute myeloid leukemia; and fialuridine – examined as a potential therapeutic for the treatment of HBV infection, however, clinical trials ended tragically. In the last section of the review derivatives with other modifications in the sugar moiety are described – carbocyclic and acyclic analogues, l-nucleosides and 5’-modified nucleosides. Among others, very important modified nucleosides are listed e.g. acyclovir, ganciclovir, DHPA, tenofovir, cyclopentenylcytosine, entecavir, carbovir, abacavir, lamivudine, telbivudine and sinefungin VA. All parts together make a possibly complete and concise review, including the latest reports, the most important groups of modified nucleosides, and should be considered as a whole. In the context of the activities description, there are references to the important molecular targets, mechanisms of action, pharmacodynamics, pharmacokinetics, toxicity, resistance, in vitro and in vivo tests or prodrug strategies, which can be a starting point for further study for chemists interested in medicinal chemistry.
    Źródło:
    Wiadomości Chemiczne; 2018, 72, 9-10; 767-787
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Aktywność biologiczna modyfikownych nukleozydów. Część 1
    Biological activity of modified nucleosides. Part 1
    Autorzy:
    Szlenkier, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/172790.pdf
    Data publikacji:
    2018
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    nukleozydy modyfikowane
    aktywność biologiczna
    cele molekularne
    mechanizm działania
    modified nucleosides
    biological activity
    molecular targets
    mechanism of action
    Opis:
    Every year, hundreds of new nucleoside analogues are obtained in laboratories around the world. As early as in 1964, 3’-azidothymidine (AZT) was first synthesized, which turned out to be the main weapon in the fight against HIV viruses 20 years later. Part I of the review includes nucleosides possessing modifications in the base moiety or having other heterocyclic bases. Nucleosides modified in the sugar residue, because of a broad spectrum of examples, will be a subject of part II and III of the review. In the group of analogues modified in the base moiety the following derivatives among others are listed: 5-iodo-2’-deoxyuridine (IDU), E-5-(2- bromovinyl)-2’-deoxyuridine (BVDU), capecitabine – prodrug form of fluorouracil, 7-deazaadenosine, BCX4430 (immucillin-A) – 9-deazaadenosine derivative active against filoviruses such as Ebola virus (EBOV). In the group of nucleosides having a different heterocyclic base the following derivatives are listed: ribavirin (RBV) and its analogues – RBV triphosphate is an inhibitor of many viral enzymes involved in the replication cycle, mizoribine (MZB) – a naturally occurring nucleosidic immunosuppressor, 5-ethynyl-1-β-"-ribofuranosyl-imidazole-4-carboxamide (EICAR) which suppresses development of murine leukemia cell lines and has a broad spectrum of activity against RNA and DNA viruses. The C-nucleosides group includes e.g. oxazinomycin – a natural antibiotic with growth inhibitory properties against gram (+), gram (–) bacteria and sarcoma, and formycin A isolated from Streptomyces lavendulae, which has cytostatic and antiviral activity.
    Źródło:
    Wiadomości Chemiczne; 2018, 72, 3-4; 109-126
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Aktywność biologiczna modyfikownych nukleozydów. Część 2
    Biological activity of modified nucleosides. Part 2
    Autorzy:
    Szlenkier, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/171742.pdf
    Data publikacji:
    2018
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    nukleozydy modyfikowane
    aktywność biologiczna
    cele molekularne
    mechanizm działania
    modified nucleosides
    biological activity
    molecular targets
    mechanism of action
    Opis:
    Part II of the review describes biological activities of nucleosides modified in the position 2’ and/or 3’ of a sugar moiety including 2’- and/or 3’-deoxy, 2’,3’-dideoxydidehydro and 2’-β-C-methylated derivatives. Analogues with a changed configuration in the sugar residue and others sugar modifications will be a subject of the part III of the review. Together with the part I it would be a short but possibly comprehensive review of nucleosides’ biological activities. In the group of analogues modified in the position 2’ and/or 3’ of the sugar moiety the following derivatives among others are listed: AZT (zidovudine) – one of the key nucleoside reverse transcriptase inhibitors (NRTI), which are the core of highly active antiretroviral therapy (HAART) against virus HIV; didanosine (ddI) – another potent NRTI with medical importance; stavudine – FDA approved NRTI; zalcitabine – historically important NRTI, however, because of a high mitochondrial toxicity is no longer in use; puromycin – a wide spectrum antibiotic which causes premature chain termination during translation, isolated from Streptomyces alboniger; gemcitabine – chemotherapy medication developed by Eli Lilly and Company and used to treat ovarian, breast, pancreas, bladder cancer and non-small cell lung carcinoma; cordycepin – the most intriguing analogue extracted from Cordyceps sp. known to traditional Chinese medicine (TCM) for centuries, possessing multi-activity against different cancer types; cladribine – used in the treatment of chronic lymphocytic leukemia, cutaneous T-cell lymphoma, hairy cell leukemia and non-Hodgkin’s lymphomas; valopicitabine – a prodrug form of 2’-C-methylcytidine, which was a promising HCV treatment agent, however, it was held during clinical trials and finally sofosbuvir developed by M.J. Sofia from Pharmasset Inc.– a ProTide prodrug form of 2’-deoxy-2’-fluoro-β-C-methyluridine 5’-monosphate, which revolutionized HCV infection therapy.
    Źródło:
    Wiadomości Chemiczne; 2018, 72, 5-6; 245-264
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Zastosowania „click chemistry” w modyfikacjach nukleozydów i oligonukleotydów
    Applications of click chemistry in modification of nucleosides and oligonucleotides
    Autorzy:
    Gładysz, M.
    Milecki, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/171589.pdf
    Data publikacji:
    2014
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    click chemistry
    CuAAC
    modyfikacje nukleozydów
    oligonukleotydy
    DNA
    kwas deoksyrybonukleinowy
    RNA
    kwas rybonukleinowy
    Click Chemistry
    nucleosides modifications
    oligonucleotides
    deoxyribonucleic acid
    ribonucleic acid
    Opis:
    Since the year 2001 new ideology of clean and simple synthesis in organic chemistry has been established. The outstanding scientists Meldal and Sharpless presented their concepts of Click Chemistry. Among the reactions chosen for this concept the reaction of Copper(I) Catalyzed Alkyne-Azide Cycloaddition (CuAAC) became the most popular one. It is the basis of syntheses employed for building blocks synthesis in medicinal chemistry and material science. Libraries of potentially pharmacologically active anticancer and antivirus compounds possessing neutral triazol linkage could be easily obtained. Remarkable efficiency of CuAAC reaction influenced on DNA- and RNAbased synthesis of novel oligonucleotides derivatives. Many of nucleic acid molecular modifications found applications in enzymatic transformation, nucleic acid hybridization, molecular tagging and gene silencing. The CuAAC reaction allows for introducing modifications into practically every region of nucleoside/nucleotide/ oligonucleotide. This includes versatile modifications of the base moiety both aiming at the base pairing ability or specific labeling of the nucleoside unit. Different conjugates (bio-, fluorescent-, affinity- or spin labels) are being attached to the base part of the nucleic acid taking advantage of the presence of azide or alkyne substituents, which can be installed without great difficulty. Labeling at the sugar part of the nucleoside can be realized at the position 2’, 3’ or 5’, the latter two giving rise to the end-labeled oligonucleotides and the 2’ position serving as the attachment point for labeling inside the oligonucleotide chain. These kind of nucleic acid modifications are very promising. Versatility of CuAAC reactions is demonstrated by numerous examples of introducing modifications into practically every reactive site of the nucleotide/oligonucleotide molecule. The review systematically presents application of the “click” technique for modification of nitrogenous base, sugar or pseudosugar moiety or phosphorus center. Possibility of creating new kind of chain linkage, devoid of negative charge and nuclease resistant is also shown. This allows to design a new class of nucleic acid analogues, similar in its DNA-mimicking properties to PNA’s.
    Źródło:
    Wiadomości Chemiczne; 2014, 68, 7-8; 617-643
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    D-Rybono-1,4-lakton. Część 2, Wykorzystanie w syntezie organicznej – wybrane reakcje
    D-Ribono-1,4-lactone. Part 2, Use in organic synthesis – selected reactions
    Autorzy:
    Madaj, J.
    Samaszko-Fiertek, J.
    Ślusarz, R.
    Dmochowska, B.
    Powiązania:
    https://bibliotekanauki.pl/articles/171521.pdf
    Data publikacji:
    2017
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    D-Rybono-1,4-lakton
    C-glikozydy
    analogi nukleozydów
    neplanocyna
    D-ribono-1,4-lactone
    C-glycosides
    nucleosides analogs
    neplanocin
    Opis:
    There are many examples of syntheses with d-ribono-1,4-lactone as a substrate. Among all, its biggest advantage is undoubtedly its accessibility. It can be synthesized on a large scale from naturally available raw materials. Its characteristic feature is the stable configuration of individual carbon atoms in multiple reaction conditions. Very important is the presence of a carbonyl moiety, allowing for a variety of additions which is crucial for carbon-carbon bond formation, the most difficult synthesis in organic chemistry. In this article we present selected examples of articles that were published after 1984. In this year, the second article describing the Use of d-Ribonolactone in Organic Synthesis [36] was published. After this time many articles describing the use of the entitled lactone as a substrate in organic synthesis were published. We thought it would be worthwhile to present in Polish a selection of them. C-Glycosides and nucleoside analogs are a particularly important type of synthesized products. Examples of their synthesis are presented in this work, namely, neplanocin A [5], B [31] and F [24], citreovirdin [14], 2-bromopyridin α- and β-d-ribofuranosides [10], 4-deazaformicin A [27] and varitriol [ 33].
    Źródło:
    Wiadomości Chemiczne; 2017, 71, 11-12; 861-885
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Wykorzystanie reakcji 1,3-dipolarnej cykloaddycji Huisgena do modyfikacji nukleozydów i ligonukleotydów
    An application of the Huisgen 1,3-dipolar cycloaddition to modify nukleosides and oligonucleotides
    Autorzy:
    Radzikowska, E.
    Powiązania:
    https://bibliotekanauki.pl/articles/171872.pdf
    Data publikacji:
    2011
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    1,3-dipolarna cykloaddycja
    analogi nukleozydów
    chemia click
    synteza modyfikowanych oligonukleotydów
    1,2,3-triazole
    biokoniugaty
    1,3-dipolar cycloaddition
    analogues of nucleosides
    click chemistry
    synthesis of modified oligonucleotide
    bioconjugates
    Opis:
    The 1,3-dipolar cycloaddition reaction between azides and terminal alkynes, known as the Huisgen reaction, constitutes a powerful tool for the synthesis of versatile molecules containing carbon – heteroatom bond. The use of a copper(I) salt in this reaction allowed Sharpless to develop the concept of „click chemistry” [1]. This strategy is based on reactions between small units characterized by mild reaction conditions, versatility, high yields and stereospecificity. The chemistry of nucleic acids and nucleoside analogues is undergoing rapid developments and numerous compounds from these classes of compounds are used in medicinal treatment. Analogues of nucleoside constitute a class of drugs that possesses either anticancer or/and antiviral activity (against HIV, HSV, VZV or HCV viruses) [3]. Many modified oligonucleotides show biological activity. As potential drugs oligonucleotides are employed in antisense, antigen and aptamer strategies. An antisense therapeutic agent acts on the pathogenic mRNA causing inactivation of the target whereas an antigen agent acts on DNA and aptamer on unwanted protein. It is not surprising that number of research groups are trying to join the concept of click chemistry with nucleic acids chemistry. In this way, it is possible to obtain new molecules like base- or sugar-modified nucleosides, nucleosides, bioconjugates and olignucleotides. The copper-catalyzed 1,3-dipolar cycloaddition CuAAC allows to functionalize DNA, for example by labelling it through attaching small molecules to DNA. Two general strategies have been developed for this purpose: presynthetic and postsynthetic labelling. In the presynthetic method nucleotide monomers are labelled before DNA synthesis and purification. In the postsynthetic strategy DNA containing small reactive groups is synthesized first and then it is conjugated with the desired molecules. CuAAC is also a convenient method for the synthesis of modified oligonucleotides in which phosphodiester linkage is replaced by 1,2,3- -triazole or for a solid phase synthesis. Such molecules appear to be useful in medicine, molecular diagnostic (e.g. fluorescent dyes) or mechanistic molecular model in the future.
    Źródło:
    Wiadomości Chemiczne; 2011, 65, 3-4; 207-234
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
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