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Sample records for acyclic nucleoside phosphonates

  1. Acyclic Nucleoside Phosphonates

    Holý, Antonín; Jansa, Petr

    Beijing: -, 2009. s. 119-119. [BIT's Annual World Summit of Antivirals 2009 /2./. 18.07.2009-20.07.2009, Beijing] R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * tenofovir * adefovir Subject RIV: CC - Organic Chemistry

  2. Synthetic approaches to novel acyclic nucleoside phosphonates

    Janeba, Zlatko

    Riga: -, 2013. s. 31-31. [Conference on Heterocycles in Bio-organic Chemistry /15./. 27.05.2013-30.05.2013, Riga] Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * antiviral * anticancer Subject RIV: CC - Organic Chemistry

  3. Novel types of acyclic nucleoside phosphonates: Chemistry and biology

    Janeba, Zlatko

    La Habana: Cuban Chemical Society, 2015. LO009. [Quimicuba 2015. Congress of Chemical Sciences, Technology and Innovation /9./. 13.10.2015-16.10.2015, La Habana] R&D Projects: GA ČR GAP207/11/0108; GA MV VG20102015046 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * malaria * tuberculosis * inhibitors * 6-oxopurine phosphoribosyltransferases Subject RIV: CC - Organic Chemistry

  4. Trends and challenges in chemistry of acyclic nucleoside phosphonates

    Krečmerová, Marcela

    Rehovot : European Federation for Medicinal Chemistry, 2015. s. 164. [International Symposium on Advances in Synthetic and Medicinal Chemistry (EFMC-ASMC'15) /6./ and Annual Meeting of the Medicinal Chemistry Section of the Israel Chemical Society /13./. 15.11.2015-18.11.2015, Rehovot] R&D Projects: GA MPO(CZ) FR-TI4/625 Institutional support: RVO:61388963 Keywords : 5-azacytosine * PME-azaC * acyclic nucleoside phosphonate * antivirals * prodrug Subject RIV: CC - Organic Chemistry

  5. Acyclic Nucleoside Phosphonates as Potential Anti-Malarial Agents

    Janeba, Zlatko; Hocková, Dana; Holý, Antonín; Česnek, Michal; Baszczyňski, Ondřej; Tichý, Tomáš; Krečmerová, Marcela; Naesens, L.; Skinner-Adams, T. S.; Edstein, M.; Keough, D. T.; de Jersey, J.; Guddat, L. W.

    Riviera Maya: -, 2011. s. 21-21. [Zing Conferences 2011. Drug Discovery - Tropical Diseases Conference. 11.12.2011-15.12.2011, Riviera Maya] R&D Projects: GA ČR GAP207/11/0108; GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * HGXPRT * malaria * Plasmodium Subject RIV: CC - Organic Chemistry

  6. Tyrosine-based prodrugs of acyclic nucleoside phosphonates

    Tichý, Tomáš; Pomeisl, Karel; Krečmerová, Marcela; McKenna, Ch. E.

    Praha : Institute of Organic Chemistry and Biochemistry AS CR, v. v. i, 2014 - (Hocek, M.), s. 126-128 ISBN 978-80-86241-50-0. - (Collection Symposium Series. 14). [Symposium on Chemistry of Nucleic Acid Components /16./. Český Krumlov (CZ), 08.06.2014-13.06.2014] R&D Projects: GA ČR(CZ) GA14-00522S Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * prodrug * tyrosine Subject RIV: CC - Organic Chemistry

  7. Oligonucleotides modified with acyclic nucleoside phosphonate (HPEP) units

    Kaiser, Martin Maxmilian; Novák, Pavel; Rosenbergová, Šárka; Poštová Slavětínská, Lenka; Rosenberg, Ivan; Janeba, Zlatko

    Praha: Institute of Organic Chemistry and Biochemistry AS CR, v. v. i, 2014 - (Hocek, M.), s. 293-294. (Collection Symposium Series. 14). ISBN 978-80-86241-50-0. [Symposium on Chemistry of Nucleic Acid Components /16./. Český Krumlov (CZ), 08.06.2014-13.06.2014] R&D Projects: GA TA ČR TA03010598 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonate * HPEP * oligonucleotides Subject RIV: CC - Organic Chemistry

  8. Synthesis and properties of novel types of chiral open-ring acyclic nucleoside phosphonates

    Holý, Antonín; Doláková, Petra

    2005-01-01

    Roč. 65, č. 3 (2005), A31. ISSN 0166-3542. [International Conference on Antiviral Research /8./. Barcelona, 11.04.2005-14.04.2005] Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonate * pyrimidine * antiviral activity Subject RIV: CC - Organic Chemistry Impact factor: 3.406, year: 2005

  9. Novel class of acyclic nucleoside phosphonates: (S)-3-hydroxy-2-(phosphonoethoxy)propyl analogues

    Kaiser, Martin Maxmilian; Dračínský, Martin; Poštová Slavětínská, Lenka; Hocková, Dana; Keough, D. T.; Guddat, L. W.; Janeba, Zlatko

    Riga: -, 2013. s. 180-180. [Conference on Heterocycles in Bio-organic Chemistry /15./. 27.05.2013-30.05.2013, Riga] R&D Projects: GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * antiparasitic * HPEP * Plasmodium Subject RIV: CC - Organic Chemistry

  10. Secretion of antiretroviral chemokines by human cells cultured with acyclic nucleoside phosphonates

    Zídek, Zdeněk; Kmoníčková, Eva; Holý, Antonín

    2007-01-01

    Roč. 574, - (2007), s. 77-84. ISSN 0014-2999 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z50390512; CEZ:AV0Z40550506 Keywords : Acyclic nucleoside phosphonate * Chemokine * Cytokine Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.376, year: 2007

  11. Synthesis of side-chain gem-difluorinated acyclic nucleoside phosphonates

    Pomeisl, Karel; Beier, Petr; Pohl, Radek; Krečmerová, Marcela

    London: Elsevier, 2014. P1.68. [Tetrahedron Symposium. Challenges in Bioorganic and Organic Medicinal Chemistry /15./. 24.06.2014-27.06.2014, London] Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * difluoromethylation * FPMPA * diethyldifluoromethylphosphonate Subject RIV: CC - Organic Chemistry

  12. Pyrimidine acyclic nucleoside phosphonates and their phosphorylated analogs as potential multisubstrate inhibitors of thymidine phosphorylase

    Pomeisl, Karel; Votruba, Ivan; Holý, Antonín; Pohl, Radek; Blažek, Jiří; Krečmerová, Marcela

    Ottawa : -, 2012. -. [Ottawa 2012 International Symposium On Biochemistry and Biophysics. 24.10.2012-25.10.2012, Ottawa] R&D Projects: GA MPO FR-TI4/625 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * thymidine phosphorylase * phosphorylation * pyrimidines Subject RIV: CC - Organic Chemistry

  13. Inhibition of hypoxanthine-guanine phosphoribosyltransferase by acyclic nucleoside phosphonates: A new class of antimalarial therapeutics

    Keough, D. T.; Hocková, Dana; Holý, Antonín; Naesens, L.; Skinner-Adams, T. S.; de Jersey, J.; Guddat, L. W.

    2009-01-01

    Roč. 52, č. 14 (2009), s. 4391-4399. ISSN 0022-2623 R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * phosphoribosyltransferase * enzyme inhibitors * Plasmodium falciparum Subject RIV: CC - Organic Chemistry Impact factor: 4.802, year: 2009

  14. Activities of Different Classes of Acyclic Nucleoside Phosphonates against BK Virus in Primary Human Renal Cells

    Topalis, D.; Lebeau, I.; Krečmerová, Marcela; Andrei, G.; Snoeck, R.

    2011-01-01

    Roč. 55, č. 5 (2011), s. 1961-1967. ISSN 0066-4804 Institutional research plan: CEZ:AV0Z40550506 Keywords : polyomavirus * BK virus * nephropathy * acyclic nucleoside phosphonates * HPMP-5-azaC Subject RIV: CC - Organic Chemistry Impact factor: 4.841, year: 2011

  15. N-Branched acyclic nucleoside phosphonates as monomers for the synthesis of modified oligonucleotides

    Hocková, Dana; Rosenbergová, Šárka; Ménová, Petra; Páv, Ondřej; Pohl, Radek; Novák, Pavel; Rosenberg, Ivan

    2015-01-01

    Roč. 13, č. 15 (2015), s. 4449-4458. ISSN 1477-0520 R&D Projects: GA ČR GAP207/11/0108; GA ČR GA13-26526S Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * oligonucleotides * solid phase synthesis Subject RIV: CC - Organic Chemistry Impact factor: 3.562, year: 2014

  16. Acyclic nucleoside phosphonates as inhibitors of Mycobacterium tuberculosis hypoxanthine-guanine phosphoribosyltransferase: Crystal structures and antituberculosis activity

    Hocková, Dana; Eng, W. S.; Špaček, Petr; Janeba, Zlatko; West, N. P.; Woods, K.; Naesens, L. M. J.; Keough, D. T.; Guddat, L. W.

    Praha: Czech Chemical Society, 2015. s. 74. [Liblice 2015. Advances in Organic, Bioorganic and Pharmaceutical Chemistry /50./. 06.11.2015-08.11.2015, Olomouc] Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * phosphoribosyltransferase * prodrugs Subject RIV: CC - Organic Chemistry

  17. Differential effects of acyclic nucleoside phosphonates on nitric oxide and cytokines in rat hepatocytes and macrophages

    Kostecká, Petra; Holý, Antonín; Farghali, H.; Zídek, Zdeněk; Kmoníčková, Eva

    2012-01-01

    Roč. 12, č. 2 (2012), s. 342-349. ISSN 1567-5769 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z50390512; CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * cytokines * nitric oxide Subject RIV: FR - Pharmacology ; Medidal Chemistry; CC - Organic Chemistry (UOCHB-X) Impact factor: 2.417, year: 2012

  18. Enhanced Topical and Transdermal Delivery of Antineoplastic and Antiviral Acyclic Nucleoside Phosphonate cPr-PMEDAP

    Vávrová, K.; Kovaříková, P.; Školová, B.; Líbalová, M.; Roh, J.; Čáp, R.; Holý, Antonín; Hrabálek, A.

    2011-01-01

    Roč. 28, č. 12 (2011), s. 3105-3115. ISSN 0724-8741 R&D Projects: GA MŠk 1M0508 Grant ostatní: GA ČR(CZ) GAP207/11/0365 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * antivirals * antineoplastics * permeation enhancer * topical skin application * transdermal delivery Subject RIV: CC - Organic Chemistry Impact factor: 4.093, year: 2011

  19. Affinity capillary electrophoresis applied to investigation of complexes of acyclic nucleoside phosphonates with beta-cyclodextrin

    Šolínová, Veronika; Mikysková, Hana; Kaiser, Martin Maxmilian; Janeba, Zlatko; Holý, Antonín; Kašička, Václav

    Ljubljana: National Institute of Chemistry, 2015 - (Vovk, I.; Glavnik, V.; Albreht, A.). s. 127 ISBN 978-961-6104-28-9. [ISSS 2015. International Symposium on Separation Sciences /21./. 30.06.2015-03.07.2015, Ljubljana] R&D Projects: GA ČR(CZ) GA13-17224S; GA MV VG20102015046 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * complexes * capillary electrophoresis Subject RIV: CB - Analytical Chemistry, Separation

  20. Determination of apparent binding constants of complexes of acyclic nucleoside phosphonates with cyclodextrins by capillary electrophoresis

    Šolínová, Veronika; Kaiser, Martin Maxmilian; Lukáč, Miloš; Janeba, Zlatko; Kašička, Václav

    Salzburg: Society of Analytical Chemistry, 2014. P510. [ISC 2014. International Symposium on Chromatography /30./. 14.09.2014-18.09.2014, Salzburg] R&D Projects: GA ČR(CZ) GAP206/12/0453; GA ČR(CZ) GA13-17224S; GA MV VG20102015046 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * capillary electrophoresis * binding constant Subject RIV: CB - Analytical Chemistry, Separation

  1. Medicinal Chemistry of Fluorinated Cyclic and Acyclic Nucleoside Phosphonates

    Baszczyňski, Ondřej; Janeba, Zlatko

    2013-01-01

    Roč. 33, č. 6 (2013), s. 1304-1344. ISSN 0198-6325 Institutional support: RVO:61388963 Keywords : nucleoside phosphosphonates * fluorine * antiviral * anticancer * antiparasitic Subject RIV: CC - Organic Chemistry Impact factor: 8.131, year: 2013

  2. Facile syntheses of pyrimidine acyclic nucleoside phosphonates and their potential evaluation for biomedical applications

    Pomeisl, Karel; Holý, Antonín; Votruba, Ivan; Nencka, Radim; Pohl, Radek

    Praha : Institute of Organic Chemistry and Biochemistry ASCR, 2008 - (Hocek, M.), s. 201-205 ISBN 978-80-86241-29-6. - (Collection Symposium Series. 10). [Symposium on Chemistry of Nucleic Acid Components /14./. Český Krumlov (CZ), 08.06.2008-13.06.2008] R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * thymidine phosphorylase * dUTPpase Subject RIV: CC - Organic Chemistry

  3. Novel oligonucleotides modified with acyclic nucleoside phosphonate units

    Janeba, Zlatko; Hocková, Dana; Kaiser, Martin Maxmilian; Ménová, Petra; Novák, Pavel; Rosenbergová, Šárka; Páv, Ondřej; Pohl, Radek; Poštová Slavětínská, Lenka; Rosenberg, Ivan

    Newport : Gordon Research Conference, 2015. [Nucleosides, Nucleotides & Oligonucleotides. Gordon Research Conference 2015. 28.06.2015-03.07.2015, Newport] R&D Projects: GA ČR GA13-26526S Institutional support: RVO:61388963 Keywords : nucleotide analogues * modified oligonucleotides Subject RIV: CC - Organic Chemistry

  4. Synthesis of phosphonomethoxyethyl or 1,3-bis(phosphonomethoxy)propan-2-yl lipophilic esters of acyclic nucleoside phosphonates

    Vrbková, Silvie; Dračínský, Martin; Holý, Antonín

    2007-01-01

    Roč. 63, č. 46 (2007), s. 11391-11398. ISSN 0040-4020 R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Grant ostatní: Descartes Prize(XE) HPAW-2002-10096 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * alkoxyalkyl phosphonates * hexadecyloxypropyl ester groups * bisphosphonates Subject RIV: CC - Organic Chemistry Impact factor: 2.869, year: 2007

  5. Synthesis and Evaluation of Novel Acyclic Nucleoside Phosphonates as Inhibitors of Plasmodium falciparum and Human 6-Oxopurine Phosphoribosyltransferases

    Kaiser, Martin Maxmilian; Hocková, Dana; Wang, T. H.; Dračínský, Martin; Poštová Slavětínská, Lenka; Procházková, Eliška; Edstein, M. D.; Chavchich, M.; Keough, D. T.; Guddat, L. W.; Janeba, Zlatko

    2015-01-01

    Roč. 10, č. 10 (2015), s. 1707-1723. ISSN 1860-7179 R&D Projects: GA MV VG20102015046; GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : 6-oxopurine * acyclic nucleoside phosphonates * phosphoribosyltransferases * malaria * phosphoramidates Subject RIV: CC - Organic Chemistry Impact factor: 2.968, year: 2014

  6. Novel type of acyclic nucleoside phosphonates derived from 2-(phosphonomethoxy)-and 2-(phosphonoethoxy)propanoic acid

    Kaiser, Martin Maxmilian; Jansa, Petr; Hocková, Dana; Dračínský, Martin; Janeba, Zlatko

    Amsterdam : Elsevier, 2012. -. [Tetrahedron Symposium: Challenges in Bioorganic & Organic Medicinal Chemistry /13./. 26.06.2012-29.06.2012, Amsterdam] R&D Projects: GA MV VG20102015046; GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * antiparasitic * 2-(phosphonomethoxy)propanoic acid * HG(X)PRTase Subject RIV: CC - Organic Chemistry

  7. Chiral analysis and characterization of acyclic nucleoside phosphonates-based antiviral drugs by capillary electrophoresis

    Kašička, Václav; Šolínová, Veronika; Sázelová, Petra; Mikysková, Hana; Koval, Dušan; Břehová, Petra; Krečmerová, Marcela; Janeba, Zlatko; Holý, Antonín

    Bratislava: Slovenská vákuová spoločnosť, 2013 - (Bodor, R.; Okenicová, L.; Staňová, A.), s. 14-17 ISBN 978-80-971179-1-7. [Analytické metódy a zdravie človeka. Medzinárodná konferencia /19./. Rajecké Teplice (SK), 24.06.2013-27.06.2013] R&D Projects: GA ČR(CZ) GAP206/12/0453; GA ČR GA13-17224S; GA MŠk(CZ) ME10040; GA MV VG20102015046 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * chiral analysis * capillary electrophoresis Subject RIV: CB - Analytical Chemistry, Separation

  8. Nucleoside and Nucleotide Analogues for the Treatment of Herpesvirus Infections: Current Stage and New Prospects in the Field of Acyclic Nucleoside Phosphonates

    Krečmerová, Marcela

    Rijeka : InTech, 2012 - (Magel, G.; Tyring, S.), s. 245-270 ISBN 978-953-51-0186-4 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * acyclic nucleoside analogue * antimetabolite * DHPA * 5-azacytosine * cidofovir * HPMPDAP * prodrugs * animal herpesviruses Subject RIV: CC - Organic Chemistry http://www.intechopen.com/books/herpesviridae-a-look-into-this-unique-family-of-viruses/nucleoside-and-nucleotide-analogues-for-the-treatment-of-herpesvirus-infections-current-stage-and-ne

  9. Estimation of apparent binding constant of complexes of selected acyclic nucleoside phosphonates with -cyclodextrin by affinity capillary electrophoresis

    Šolínová, Veronika; Mikysková, Hana; Kaiser, Martin Maxmilian; Janeba, Zlatko; Holý, Antonín; Kašička, Václav

    2016-01-01

    Roč. 37, č. 2 (2016), s. 239-247. ISSN 0173-0835 R&D Projects: GA ČR(CZ) GA13-17224S; GA ČR(CZ) GA15-01948S Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * affinity capillary electrophoresis * binding constant * nucleotide analogs * beta-cyclodextrin Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.028, year: 2014

  10. Acyclic nucleoside phosphonates as inhibitors of hypoxanthine-guanine-(xanthine) phosphoribosyltransferase: new anti-malarial chemotherapy leads

    Hocková, Dana; Holý, Antonín; Česnek, Michal; Baszczyňski, Ondřej; Tichý, Tomáš; Krečmerová, Marcela; Janeba, Zlatko; Skinner-Adams, T.; Naesens, L.; Keough, D. T.; de Jersey, J.; Guddat, L. W.

    Praha : ČSCH, 2011. s. 21-21. [Pokroky v organické, bioorganické a farmaceutické chemii - "Liblice 2011" /46./. 11.11.2011-13.11.2011, Lázně Bělohrad] R&D Projects: GA ČR GAP207/11/0108; GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : nucleotide analogues * antiviral activity * antiplasmodial activity * acyclic nucleoside phosphonates Subject RIV: CC - Organic Chemistry

  11. Enantiopurity analysis of new types of acyclic nucleoside phosphonates by capillary electrophoresis with cyclodextrins as chiral selectors

    Šolínová, Veronika; Kaiser, Martin Maxmilian; Lukáč, Miloš; Janeba, Zlatko; Kašička, Václav

    2014-01-01

    Roč. 37, č. 3 (2014), s. 295-303. ISSN 1615-9306 R&D Projects: GA ČR(CZ) GAP206/12/0453; GA ČR(CZ) GA13-17224S; GA MV VG20102015046 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * CE * chiral analysis * cyclodextrin s * nucleotide analogs Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.737, year: 2014

  12. Syntheses of pyrimidine acyclic nucleoside phosphonates as potent inhibitors of thymidine phosphorylase (PD-ECGF) from SD-lymphoma

    Pomeisl, Karel; Votruba, Ivan; Holý, Antonín; Pohl, Radek

    2007-01-01

    Roč. 26, 8/9 (2007), s. 1025-1028. ISSN 1525-7770. [International Roundtable /17./. Bern, 03.09.2006-07.09.2006] R&D Projects: GA MŠk 1M0508 Grant ostatní: Descartes Prize(XE) HPAW-CT-2002-9001 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * thymidine phosphorylase * pyrimidines * FPMP derivatives * fluorination Subject RIV: CC - Organic Chemistry Impact factor: 0.723, year: 2007

  13. Activities of several classes of acyclic nucleoside phosphonates against camelpox virus replication in different cell culture models

    Duraffour, S.; Snoeck, R.; Krečmerová, Marcela; Van Den Oord, J.; De Vos, D.; Holý, Antonín; Crance, J. M.; Garin, D.; De Clercq, E.; Andrei, G.

    2007-01-01

    Roč. 51, č. 12 (2007), s. 4410-4419. ISSN 0066-4804 R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Grant ostatní: FWO(BE) G.0267.04; NIH(US) AI06540-01 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * antivirals * HPMP-5-azacytosine * camelpox virus Subject RIV: CC - Organic Chemistry Impact factor: 4.390, year: 2007

  14. Assessment of chiral purity of acyclic nucleoside phosphonates-based anti-AIDS drugs by capillary electrophoresis

    Sázelová, Petra; Šolínová, Veronika; Kašička, Václav; Holý, Antonín

    Baltimore Inner Harbor, MD, 2010. s. 74-75. [International Symposium on Electro- and Liquid Phase-separation Techniques /17./. 29.08.2010-01.09.2010, Baltimore Inner Harbor, MD] R&D Projects: GA ČR(CZ) GA203/08/1428; GA ČR(CZ) GA203/09/0675 Institutional research plan: CEZ:AV0Z40550506 Keywords : chiral analysis * acyclic nucleoside phosphonates * capillary electrophoresis Subject RIV: CB - Analytical Chemistry, Separation

  15. Influence of Acyclic Nucleoside Phosphonate Antivirals on Gene Expression of Chemokine Receptors CCR5 and CXCR4

    Potměšil, P.; Holý, Antonín; Zídek, Zdeněk

    2015-01-01

    Roč. 61, č. 1 (2015), s. 1-7. ISSN 0015-5500 R&D Projects: GA ČR GA305/03/1470; GA MŠk 1M0508 Institutional support: RVO:61388963 ; RVO:68378041 Keywords : acyclic nucleoside phosphonate * HIV * CCR5 * CXCR4 * cytokine * RT-PCR Subject RIV: CC - Organic Chemistry; FR - Pharmacology ; Medidal Chemistry (UEM-P) Impact factor: 1.000, year: 2014

  16. Acyclic Nucleoside Phosphonates as Inhibitors of Hypoxanthine-Guanine-Xanthine Phosphoribosyltransferase: New Anti-Malarial Chemotherapy Leads

    Hocková, Dana; Holý, Antonín; Česnek, Michal; Baszczyňski, Ondřej; Tichý, Tomáš; Krečmerová, Marcela; Janeba, Zlatko; Skinner-Adams, T. S.; Naesens, L.; Keough, D. T.; de Jersey, J.; Guddat, L. W.

    Praha : Institute of Organic Chemistry and Biochemistry AS CR, v. v. i., 2011 - (Hocek, M.), s. 171-174 ISBN 978-80-86241-37-1. - (Collection Symposium Series. 12). [Chemistry of Nucleic Acid Components /15./. Český Krumlov (CZ), 05.06.2011-10.06.2011] R&D Projects: GA MŠk 1M0508; GA ČR GAP207/11/0108 Institutional research plan: CEZ:AV0Z40550506 Keywords : ANPs * acyclic nucleoside phosphonates * anti-malarial * Plasmodium * HGXPRTase Subject RIV: CC - Organic Chemistry

  17. Inhibitory activities of three classes of acyclic nucleoside phosphonates against murine polyomavirus and primate simian virus 40 strains

    Lebeau, I.; Andrei, G.; Krečmerová, Marcela; De Clercq, E.; Holý, Antonín; Snoeck, R.

    2007-01-01

    Roč. 51, č. 6 (2007), s. 2268-2273. ISSN 0066-4804 R&D Projects: GA AV ČR 1QS400550501; GA MŠk 1M0508 Grant ostatní: FWO(BE) G.0267.04; NIH(US) AI 062540-01; René Descartes Prize 2001(XE) HPAV-2002-100096 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * polyomavirus * 5-azacytosine Subject RIV: CC - Organic Chemistry Impact factor: 4.390, year: 2007

  18. Enantiopurity analysis of anti-AIDS drugs and related acyclic nucleoside phosphonates-based antivirotics by capillary electrophoresis

    Kašička, Václav; Šolínová, Veronika; Sázelová, Petra; Mikysková, Hana; Koval, Dušan; Holý, Antonín

    Alphaville: AlphaGraphics, 2013 - (Guzman, N.; Tavares, M.). s. 32-32 [LACE 2013. Latin-American Symposium on Biotechnology, Biomedical, Biopharmaceutical, and Industrial Applications of Capillary Electrophoresis and Microchip Technology /19./. 29.11.2013-03.12.2013, Lima] R&D Projects: GA ČR(CZ) GAP206/12/0453; GA ČR(CZ) GA13-17224S; GA MŠk(CZ) ME10040; GA MV VG20102015046 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * capillary electrophoresis * chiral analysis Subject RIV: CB - Analytical Chemistry, Separation

  19. Synthesis of acyclic nucleoside phosphonates bearing (N-methyl)anthraniloyl substituent as potential inhibitors of adenylate cyclase toxin from Bordetella Pertussis

    Břehová, Petra; Šmídková, Markéta; Mertlíková-Kaiserová, Helena; Dračínský, Martin; Janeba, Zlatko

    Praha: Czech Chemical Society, 2015. s. 61. [Liblice 2015. Advances in Organic , Bioorganic and Pharmaceutical Chemistry /50./. 06.11.2015-08.11.2015, Olomouc] R&D Projects: GA MV VG20102015046 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * adenylate cyclase toxin * prodrugs Subject RIV: CC - Organic Chemistry

  20. Enantioseparation of newly synthesized acyclic nucleoside phosphonates-based antivirals by capillary electrophoresis using cyclodextrins as chiral selectors

    Šolínová, Veronika; Kaiser, Martin Maxmilian; Lukáč, Miloš; Janeba, Zlatko; Kašička, Václav

    Bratislava : Slovenská vákuová spoločnosť, 2013 - (Bodor, R.; Okenicová, L.; Staňová, A.), s. 245-247 ISBN 978-80-971179-1-7. [Analytické metódy a zdravie človeka. Medzinárodná konferencia /19./. Rajecké Teplice (SK), 24.06.2013-27.06.2013] R&D Projects: GA ČR(CZ) GAP206/12/0453; GA ČR GA13-17224S; GA MV VG20102015046 Grant ostatní: AV ČR CSIC(CZ) 2008CZ0019 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * chiral analysis * capillary electrophoresis Subject RIV: CB - Analytical Chemistry, Separation

  1. Synthesis of branched 9-[2-(2-phosphonoethoxy)ethyl]purines as a new class of acyclic nucleoside phosphonates which inhibit Plasmodium falciparum hypoxanthine-guanine-xanthine phosphoribosyltransferase

    Hocková, Dana; Holý, Antonín; Masojídková, Milena; Keough, D. T.; de Jersey, J.; Guddat, L. W.

    2009-01-01

    Roč. 17, č. 17 (2009), s. 6218-6232. ISSN 0968-0896 R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * drug design * phosphoribosyltransferase * enzyme inhibitors * purine salvage pathway Subject RIV: CC - Organic Chemistry Impact factor: 2.822, year: 2009

  2. Pd-catalyzed Suzuki-Miyaura coupling reaction in the synthesis of 5-aryl substituted pyrimidine acyclic nucleoside phosphonates as potential multisubstrate inhibitors of thymidine phosphorylase

    Pomeisl, Karel; Holý, Antonín; Pohl, Radek

    Dublin : University College Dublin, 2007. s. 329. [European Symposium on Organic Chemistry /15./. 08.07.2007-13.07.2007, Dublin] R&D Projects: GA MŠk 1M0508 Grant ostatní: Descartes Prize(XE) HPAW-CT-2002-9001 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * thymidine phosphorylase * Suzuki coupling Subject RIV: CC - Organic Chemistry

  3. Sonogashira cross-coupling in the synthesis of acyclic nucleoside phosphonates: preparation of 6-[(phosphonomethoxy)alkynyl]- and 6-[(phosphonomethoxy)alkyl]pyrimidines

    Hocková, Dana; Masojídková, Milena; Holý, Antonín

    2005-01-01

    Roč. 70, č. 2 (2005), 247-257. ISSN 0010-0765 R&D Projects: GA AV ČR(CZ) IBS4055109 Grant ostatní: René Descartes Prize 2001(XE) HPAW-2002-90001 Institutional research plan: CEZ:AV0Z40550506 Keywords : nucleotide analogues * acyclic nucleoside phosphonates * pyrimidines Subject RIV: CC - Organic Chemistry Impact factor: 0.949, year: 2005

  4. Activity of novel acyclic pyrimidine nucleoside phosphonates against different DNA polymerase mutants of herpes simplex virus type 1 (HSV-1)

    Andrei, G.; Holý, Antonín; Fiten, P.; Opdenakker, G.; De Clercq, E.; Snoeck, R.

    Chicago, 2003. s. 490. [Interscience Conference on Antimicrobial Agents and Chemotherapy /43./. 14.09.2003-17.09.2003, Chicago] Institutional research plan: CEZ:AV0Z4055905 Keywords : pyrimidine nucleoside phosphonates Subject RIV: CC - Organic Chemistry

  5. The preparation of 3-H-labeled Acyclic Nucleoside Phosphonates and Study of their Stability

    Elbert, Tomáš; Břehová, Petra; Holý, Antonín

    2010-01-01

    Roč. 75, č. 7 (2010), s. 757-766. ISSN 0010-0765 R&D Projects: GA MŠk 1M0508; GA AV ČR IAA400550801 Institutional research plan: CEZ:AV0Z40550506 Keywords : tritium * 3-H NMR * acyclic nucleotide analogues Subject RIV: CC - Organic Chemistry Impact factor: 0.853, year: 2010

  6. Acyclic nucleoside phosphonates with 5-azacytosine moiety: A new class of antiviral agents

    Krečmerová, Marcela; Holý, Antonín; Pískala, Alois; Masojídková, Milena; Andrei, G.; Snoeck, R.; Naesens, L.; Balzarini, J.; Neyts, J.; De Clercq, E.

    Bern : DCB University of Bern, 2006. s. 340. [IRT-International Roundtable on Nucleosides, Nucleotides and Nucleic Acids /17./. 03.09.2006-07.09.2006, Bern] R&D Projects: GA MŠk(CZ) 1M0508; GA AV ČR(CZ) 1QS400550501 Grant ostatní: Descartes Prize(XE) HPAW-2002-100096; NIAID/NIH(US) UC1AI062540-01 Institutional research plan: CEZ:AV0Z40550506 Keywords : HPMP-5-azaC * 5-azacytosine * antiviral activity Subject RIV: CC - Organic Chemistry

  7. Evaluation of Novel Acyclic Nucleoside Phosphonates against Human and Animal Gammaherpesviruses Revealed an Altered Metabolism of Cyclic Prodrugs upon Epstein-Barr Virus Reactivation in P3HR-1 Cells

    Coen, N.; Duraffour, S.; Naesens, L.; Krečmerová, Marcela; Van Den Oord, J.; Snoeck, R.; Andrei, G.

    2013-01-01

    Roč. 87, č. 22 (2013), s. 12422-12432. ISSN 0022-538X R&D Projects: GA MPO FR-TI4/625 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonate * gammaherpesvirus * Epstein-Barr virus * Kaposi's sarcoma * HPMP-5-azaC * cidofovir Subject RIV: EE - Microbiology, Virology Impact factor: 4.648, year: 2013

  8. Acyclic nucleoside phosphonates as a new class of anti-malarial compounds: Inhibition of Plasmodium falciparum hypoxanthine-guanine-xanthine phosphoribosyltransferase by 9-[2-(2-phosphonoethoxy)ethyl]-purines and their branched derivatives

    Hocková, Dana; Holý, Antonín; Keough, D. T.; Naesens, L.; Skinner-Adams, T. S.; de Jersey, J.; Guddat, L. W.

    Praha : -, 2009. -. ISBN 978-80-02-02160-5. [ESOC 2009. European Symposium on Organic Chemistry /16./. 12.07.2009-16.07.2009, Praha] Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * anti-malarial compounds Subject RIV: CC - Organic Chemistry

  9. Acyclic nucleoside phosphonates as inhibitors of mycobacterium tuberculosis hypoxanthine-guanine phosphoribosyltransferase: Crystal structures and antituberculosis activity

    Hocková, Dana; Eng, W. S.; Špaček, Petr; Janeba, Zlatko; West, N. P.; Woods, K.; Naesens, L. M. J.; Keough, D. T.; Guddat, L. W.

    Newport: Gordon Research Conference, 2015. [Nucleosides, Nucleotides & Oligonucleotides. Gordon Research Conference 2015. 28.06.2015-03.07.2015, Newport] Institutional support: RVO:61388963 Keywords : nucleotide analogues * enzyme inhibitors * tuberculosis Subject RIV: CC - Organic Chemistry

  10. Novel Type of Acyclic Nucleoside Phosphonates as Inhibitors of 6-Oxopurine Phosphoribosyltransferases: New Potential Antimalarial Chemotherapy Leads

    Hocková, Dana; Keough, D. T.; Janeba, Zlatko; Wang, T.; de Jersey, J.; Guddat, L. W.

    Montreal: International Society of Nucleosides, Nucleotides and Nucleic Acids, 2012. -. [International Round Table on Nucleosides Nucleotides and Nucleic Acids /20./. 05.08.2012-09.08.2012, Montreal] R&D Projects: GA ČR GAP207/11/0108 Grant ostatní: National Health and Medical Research Council(AU) NHMRC 1030353 Institutional research plan: CEZ:AV0Z40550506 Keywords : nucleotide analogues * enzyme inhibitors * Plasmodium Subject RIV: CC - Organic Chemistry

  11. The Acyclic 2,4-Diaminopyrimidine Nucleoside Phosphonate Acts as a Purine Mimetic in HIV-1 Reverse Transcriptase DNA Polymerization

    Herman, B. D.; Votruba, Ivan; Holý, Antonín; Sluis-Cremer, N.; Balzarini, J.

    2010-01-01

    Roč. 285, č. 16 (2010), s. 12101-12108. ISSN 0021-9258 Grant ostatní: NIH(US) R01 AI81571; KU Leuven(BE) GOA Kredit 05/19 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleotide analogue * purine open ring * HIV -1 RT * antiviral * antimetabolite Subject RIV: CC - Organic Chemistry Impact factor: 5.328, year: 2010

  12. Piperidine nucleoside phosphonic acid derivatives

    Kovačková, Soňa; Dračínský, Martin; Rejman, Dominik

    Praha : Institute of Organic Chemistry and Biochemistry AS CR, v. v. i., 2011 - (Hocek, M.), s. 372-374 ISBN 978-80-86241-37-1. - (Collection Symposium Series. 12). [Chemistry of Nucleic Acid Components /15./. Český Krumlov (CZ), 05.06.2011-10.06.2011] Institutional research plan: CEZ:AV0Z40550506 Keywords : piperidine nucleoside * nucleoside phosphonic acids * nucleoside diphosphate analogs * nucleotide analogs Subject RIV: CC - Organic Chemistry

  13. Synthesis and properties of chiral open-ring acyclic nucleoside bisphosphonates

    Doláková, Petra; Masojídková, Milena; Holý, Antonín

    Praha : ÚOCHB AV ČR, 2005 - (Hocek, M.), s. 395-396 ISBN 80-86241-25-4. - (Collection Symposium Series. 7). [Chemistry of Nucleic Acid Components /13./. Špindlerův Mlýn (CZ), 03.09.2005-09.09.2005] R&D Projects: GA MŠk(CZ) 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonate * pyrimidine * antiviral activity Subject RIV: CC - Organic Chemistry

  14. Synthesis and properties of chiral open-ring acyclic nucleoside bisphosphonates

    Doláková, Petra; Dračínský, Martin; Holý, Antonín

    Elsevier. Roč. 74, č. 3 (2007), A72. ISSN 0166-3542. [Conference on Antiviral Research. 29.04.2007-03.05.2007, Palm Springs] R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Grant ostatní: René Descartes Prize-2001(XE) HPAW-2002-100096 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonate * bisphosphonate * pyrimidine Subject RIV: CC - Organic Chemistry

  15. Tetrofuranose nucleoside phosphonic acids: Synthesis and properties

    Poláková, Ivana; Buděšínský, Miloš; Točík, Zdeněk; Rosenberg, Ivan

    2011-01-01

    Roč. 76, č. 5 (2011), s. 503-536. ISSN 0010-0765 R&D Projects: GA AV ČR KAN200520801; GA ČR GA203/09/0820; GA MŠk(CZ) LC06061; GA MŠk(CZ) LC06077 Institutional research plan: CEZ:AV0Z40550506 Keywords : tetrofuranosyl phosphonate * nucleotide analogues * phosphonomethoxy nucleosides * sugar hydroxyphosphonates Subject RIV: CC - Organic Chemistry Impact factor: 1.283, year: 2011

  16. Therapeutic potential of acyclic nucleoside phosphonates

    Janeba, Zlatko

    Lima: Peruvian Chemical Society, 2014. [Latin American Chemistry Congress /31./ and Peruvian Chemistry Congress /27./. 14.10.2014-17.10.2014, Lima] Institutional support: RVO:61388963 Keywords : ANPs * malaria * antivirals Subject RIV: CC - Organic Chemistry

  17. Synthesis of some novel hydrazono acyclic nucleoside analogues

    Mohammad N. Soltani Rad

    2010-05-01

    Full Text Available The syntheses of novel hydrazono acyclic nucleosides similar to miconazole scaffolds are described. In this series of acyclic nucleosides, pyrimidine as well as purine and other azole derivatives replaced the imidazole function in miconazole and the ether group was replaced with a hydrazone moiety using phenylhydrazine. To interpret the dominant formation of (E-hydrazone derivatives rather than (Z-isomers, PM3 semiempirical quantum mechanic calculations were carried out which indicated that the (E-isomers had the lower heats of formation.

  18. Acyclic Immucillin Phosphonates. Second-Generation Inhibitors of Plasmodium falciparum Hypoxanthine- Guanine-Xanthine Phosphoribosyltransferase

    Hazelton, Keith Z. [Yeshiva Univ., New York, NY (United States); Ho, Meng-Chaio [Yeshiva Univ., New York, NY (United States); Cassera, Maria B. [Yeshiva Univ., New York, NY (United States); Clinch, Keith [Industrial Research Ltd., Lower Hutt (New Zealand); Crump, Douglas R. [Industrial Research Ltd., Lower Hutt (New Zealand); Rosario Jr., Irving [Yeshiva Univ., New York, NY (United States); Merino, Emilio F. [Yeshiva Univ., New York, NY (United States); Almo, Steve C. [Yeshiva Univ., New York, NY (United States); Tyler, Peter C. [Industrial Research Ltd., Lower Hutt (New Zealand); Schramm, Vern L. [Yeshiva Univ., New York, NY (United States)

    2012-06-22

    We found that Plasmodium falciparum is the primary cause of deaths from malaria. It is a purine auxotroph and relies on hypoxanthine salvage from the host purine pool. Purine starvation as an antimalarial target has been validated by inhibition of purine nucleoside phosphorylase. Hypoxanthine depletion kills Plasmodium falciparum in cell culture and in Aotus monkey infections. Hypoxanthine-guanine-xanthine phosphoribosyltransferase (HGXPRT) from P. falciparum is required for hypoxanthine salvage by forming inosine 5'-monophosphate, a branchpoint for all purine nucleotide synthesis in the parasite. We present a class of HGXPRT inhibitors, the acyclic immucillin phosphonates (AIPs), and cell permeable AIP prodrugs. The AIPs are simple, potent, selective, and biologically stable inhibitors. The AIP prodrugs block proliferation of cultured parasites by inhibiting the incorporation of hypoxanthine into the parasite nucleotide pool and validates HGXPRT as a target in malaria.

  19. Synthesis of chiral open-ring acyclic nucleoside bisphosphonates

    Doláková, Petra; Masojídková, Milena; Dračínský, Martin; Holý, Antonín

    Napoli : University of Napoli, 2006. s. 73. [International Symposium on Applied Bioinorganic Chemistry /9./. 02.12.2006-05.12.2006, Napoli] R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Grant ostatní: René Descartes Prize(XE) HPAW-2002-100096 Institutional research plan: CEZ:AV0Z40550506 Keywords : purine * acyclic nucleoside bisphosphonates Subject RIV: CC - Organic Chemistry

  20. Distinct modulation of telomere length in two T-lymphoblastic leukemia cell lines by cytotoxic nucleoside phosphonates PMEG and PMEDAP

    Hájek, Miroslav; Cvilink, Viktor; Votruba, Ivan; Holý, Antonín; Mertlíková-Kaiserová, Helena

    2010-01-01

    Roč. 643, č. 1 (2010), s. 6-12. ISSN 0014-2999 R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * PMEG * PMEDAP * telomere length * telomerase inhibition Subject RIV: CC - Organic Chemistry Impact factor: 2.737, year: 2010

  1. Prolinol-based nucleoside phosphonic acids: Synthesis and properties

    Vaněk, Václav; Buděšínský, Miloš; Liboska, Radek; Hurychová, Vladimíra; Rosenberg, Ivan

    -, č. 52 (2008), s. 537-538. ISSN 0261-3166. [Joint Symposium of the International Roundtable on Nucleosides, Nucleotides and Nucleic Acids /18./ and the International Symposium on Nucleic Acid Chemistry /35./. Kyoto, 08.09.2008-12.09.2008] R&D Projects: GA MŠk(CZ) LC06061; GA MŠk(CZ) LC06077; GA MŠk LC512 Institutional research plan: CEZ:AV0Z40550506 Keywords : oligonucleotide phosphonate * nucleoside analogue * pyrrolidine * prolinol Subject RIV: CC - Organic Chemistry

  2. Nucleoside phosphonic acids in thymidine phosphorylase inhibition: Structure - activity relationship

    Panova, Natalya; Kóšiová, Ivana; Petrová, Magdalena; Vaněk, Václav; Liboska, Radek; Kovačková, Soňa; Kočalka, Petr; Králíková, Šárka; Točík, Zdeněk; Páv, Ondřej; Pačes, Ondřej; Rejman, Dominik; Rosenberg, Ivan

    -, č. 52 (2008), s. 665-666. ISSN 0261-3166. [Joint Symposium of the International Roundtable on Nucleosides, Nucleotides and Nucleic Acids /18./ and the International Symposium on Nucleic Acid Chemistry /35./. Kyoto, 08.09.2008-12.09.2008] R&D Projects: GA MŠk(CZ) LC06061; GA MŠk(CZ) LC06077; GA MŠk LC512 Institutional research plan: CEZ:AV0Z40550506 Keywords : thymidine phosphorylase * inhibitors * phosphonic acids Subject RIV: CC - Organic Chemistry

  3. Synthesis and Conformation of Novel 4'-Fluorinated 5'-Deoxythreosyl Phosphonic Acid Nucleosides as Antiviral Agents

    Efficient synthetic route to novel 4'-fluorinated 5'-deoxythreosyl phosphonic acid nucleosides was described from glyceraldehyde using Horner-Emmons reaction in the presence of triethyl α-fluorophosphonoacetate. Glycosylation reaction of nucleosidic bases with glycosly donor 14 gave the nucleosides which were further phosphonated and hydrolyzed to reach desired nucleoside analogues. Synthesized nucleoside analogues 18, 21, 25 and 28 were tested for anti-HIV activity as well as cytotoxicity. Adenine derivatives 18 and 21 showed significant anti-HIV activity up to 100 μM

  4. Efficient synthesis of "open-ring" acyclic nucleoside phosphonates

    Jansa, Petr; Holý, Antonín; Masojídková, Milena

    Marburg : University of Marburg, 2006. s. 111. ISBN 3-89703-685-1. [Joint Meeting of the Czech, German and Hungarian Pharmaceutical Societies. 04.10.2006-07.10.2006, Marburg] R&D Projects: GA MŠk(CZ) 1M0508 Grant ostatní: Descartes Prize(XE) HPAW-2002-100096 Institutional research plan: CEZ:AV0Z40550506 Keywords : open-ring ANPs * pyrimidines Subject RIV: CC - Organic Chemistry

  5. Acyclic nucleoside phosphonates: A key class of antiviral drugs

    De Clercq, E.; Holý, Antonín

    2005-01-01

    Roč. 4, č. 13 (2005), 928-940. ISSN 1474-1776 Institutional research plan: CEZ:AV0Z4055905 Keywords : tenofovir * adefovir * cidofovir Subject RIV: CC - Organic Chemistry Impact factor: 18.775, year: 2005

  6. Preparation of tetrofuranosylnucleoside phosphonic acids as shortened analogues of 5´-nucleoside phosphates

    Točík, Zdeněk; Poláková, Ivana; Buděšínský, Miloš; Rosenberg, Ivan

    Lyon : Université de Lyon, 2010, s. 345-346. [International Roundtable on Nucleosides, Nucleotides and Nucleic Acids. IRT 2010. Lyon (FR), 29.08.2010-03.09.2010] R&D Projects: GA MŠk(CZ) LC06077; GA ČR GA203/09/0820 Institutional research plan: CEZ:AV0Z40550506 Keywords : phosphonate nucleoside * nucleotide analog * tetrofuranosylnucleoside phosphonate Subject RIV: CC - Organic Chemistry http://irt2010.univ-lyon1.fr

  7. Synthesis and conformation of novel 3'-branched threo syl-5'-deoxy phosphonic acid nucleoside analogues

    The discovery that threo syl phosphonate nucleoside (PMDTA, EC50 = 2.53 μM) is a potent anti-HIV agent has led to the synthesis and biological evaluation of 5'-deoxy versions of threo syl phosphonate nucleosides. In the present study, (E)-3'-phosphono alkenyl and 3'-phosphono alkyl nucleoside analogues 13, 16, 20 and 23 were synthesized from acetol and tested for anti-HIV activity and cytotoxicity. The adenine analogue 16 was found to exhibit moderate in vitro anti-HIV-1 activity (EC50 = 22.2 μM)

  8. Nucleoside phosphonic acids as selective inhibitors of human pyrimidine- specific 5'-nucleotidases

    Šimák, Ondřej (ed.); Buděšínský, Miloš; Petrová, Magdalena; Zborníková, Eva; Pachl, Petr; Brynda, Jiří; Rosenberg, Ivan

    Montreal : International Society of Nucleosides, Nucleotides and Nucleic Acids, 2012. s. 49-49. [International Round Table on Nucleosides Nucleotides and Nucleic Acids /20./. 05.08.2012-09.08.2012, Montreal] R&D Projects: GA AV ČR KAN200520801; GA ČR GA203/09/0820 Institutional support: RVO:61388963 ; RVO:68378050 Keywords : nucleoside phosphonic acids Subject RIV: CC - Organic Chemistry

  9. Synthesis of Novel 2'-Spirocyclopropanoid 4'-Deoxythreosyl Phosphonic Acid Nucleoside Analogues

    Efficient synthetic route to novel 2'-spirocyclopropanoid 4'-deoxythreosyl phosphonic acid nucleosides was described from 1,4-dihydroxy-2-butene. Cyclopropane moiety was prepared via ester enolate alkylation using (2-chloroethyl)dimethylsulfonium iodide. Synthesized nucleoside analogues 16, 19, 23 and 26 were tested for anti-HIV activity as well as cytotoxicity. However, none of them showed any anti-HIV activity or cytotoxicity up to 100 μM

  10. Synthesis of Novel 2'-Spirocyclopropanoid 4'-Deoxythreosyl Phosphonic Acid Nucleoside Analogues

    Shen, Guang Huan; Hong, Joon Hee [Chosun Univ., Kwangju (Korea, Republic of)

    2013-03-15

    Efficient synthetic route to novel 2'-spirocyclopropanoid 4'-deoxythreosyl phosphonic acid nucleosides was described from 1,4-dihydroxy-2-butene. Cyclopropane moiety was prepared via ester enolate alkylation using (2-chloroethyl)dimethylsulfonium iodide. Synthesized nucleoside analogues 16, 19, 23 and 26 were tested for anti-HIV activity as well as cytotoxicity. However, none of them showed any anti-HIV activity or cytotoxicity up to 100 μM.

  11. Synthesis and Conformation of Novel 4'-Fluorinated 5'-Deoxythreosyl Phosphonic Acid Nucleosides as Antiviral Agents

    Kang, Lien; Kim, Eunae; Choi, Eun Joo; Yoo, Jin Cheol; Lee, Wonjae; Hong, Joon Hee [Chosun Univ., Kwangju (Korea, Republic of)

    2012-12-15

    Efficient synthetic route to novel 4'-fluorinated 5'-deoxythreosyl phosphonic acid nucleosides was described from glyceraldehyde using Horner-Emmons reaction in the presence of triethyl α-fluorophosphonoacetate. Glycosylation reaction of nucleosidic bases with glycosly donor 14 gave the nucleosides which were further phosphonated and hydrolyzed to reach desired nucleoside analogues. Synthesized nucleoside analogues 18, 21, 25 and 28 were tested for anti-HIV activity as well as cytotoxicity. Adenine derivatives 18 and 21 showed significant anti-HIV activity up to 100 μM.

  12. Inhibition of the Escherichia coli 6-oxopurine phosphoribosyltransferases by nucleoside phosphonates: potential for new antibacterial agents

    Keough, D. T.; Hocková, Dana; Rejman, Dominik; Špaček, Petr; Vrbková, Silvie; Krečmerová, Marcela; Eng, W. S.; Jans, H.; West, N. P.; Naesens, L. M. J.; de Jersey, J.; Guddat, L. W.

    2013-01-01

    Roč. 56, č. 17 (2013), s. 6967-6984. ISSN 0022-2623 R&D Projects: GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : nucleoside phosphonates * antibacterial agents * hypoxanthine-guanine phosphoribosyltransferase * state analog inhibitor * antimalarial chemotherapy Subject RIV: CC - Organic Chemistry Impact factor: 5.480, year: 2013

  13. Nucleoside phosphonic acids in oligonucleotide chemistry: Structural diversity versus properties of isopolar phosphonate internucleotide linkages

    Hurychová, Vladimíra; Kóšiová, Ivana; Kovačková, Soňa; Králíková, Šárka; Liboska, Radek; Pačes, Ondřej; Páv, Ondřej; Petrová, Magdalena; Rejman, Dominik; Rosenberg, Ivan; Točík, Zdeněk

    Berlin : Oligonucleotide Therapeutic Society, 2007. s. 244-245. [Annual Meeting of the Oligonucleotide Therapeutics Society /3./. 04.10.2007-06.10.2007, Berlin] R&D Projects: GA MŠk(CZ) LC06077; GA MŠk(CZ) LC06061; GA ČR GA203/05/0827; GA ČR GA202/05/0628 Institutional research plan: CEZ:AV0Z40550506 Keywords : phosphonic acids * oligonucleotides * isopolar phosphonate * internucleotide linkage Subject RIV: CC - Organic Chemistry

  14. Acyclic nucleoside bisphosphonates as inhibitors of hypoxanthine-guanine-(xanthine) phosphoribosyltransferases: Potential new anti-malarial compounds

    Špaček, Petr; Hocková, Dana; Janeba, Zlatko; Vrbková, Silvie; Edstein, M.; de Jersey, J.; Keough, D. T.; Guddat, L. W.

    Amsterdam : Elsevier, 2012. P2.24-P2.24. [Tetrahedron Symposium: Challenges in Bioorganic & Organic Medicinal Chemistry /13./. 26.06.2012-29.06.2012, Amsterdam] Institutional research plan: CEZ:AV0Z40550506 Keywords : nucleoside phosphonates * biophosphonates Subject RIV: CC - Organic Chemistry

  15. Synthesis and conformation of novel 3'-branched threo syl-5'-deoxy phosphonic acid nucleoside analogues

    Shen, Guang Huan; Kang, Li En; Kim, Eun Ae; Lee, Won Jae; Hong, Joon Hee [Chosun Univ., Kwangju (Korea, Republic of)

    2012-04-15

    The discovery that threo syl phosphonate nucleoside (PMDTA, EC{sub 50} = 2.53 μM) is a potent anti-HIV agent has led to the synthesis and biological evaluation of 5'-deoxy versions of threo syl phosphonate nucleosides. In the present study, (E)-3'-phosphono alkenyl and 3'-phosphono alkyl nucleoside analogues 13, 16, 20 and 23 were synthesized from acetol and tested for anti-HIV activity and cytotoxicity. The adenine analogue 16 was found to exhibit moderate in vitro anti-HIV-1 activity (EC{sub 50} = 22.2 μM)

  16. Microwave-assisted hydrolysis of phosphonate diesters: an efficient protocol for the preparation of phosphonic acids

    Jansa, Petr; Baszczyňski, Ondřej; Procházková, Eliška; Dračínský, Martin; Janeba, Zlatko

    2012-01-01

    Roč. 14, č. 8 (2012), s. 2282-2288. ISSN 1463-9262 R&D Projects: GA MV VG20102015046 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * DNA virus * retrovirus infections * cidofovir * organic-synthesis Subject RIV: CC - Organic Chemistry Impact factor: 6.828, year: 2012

  17. Conformationally constrained nucleoside phosphonic acids - potent inhibitors of human mitochondrial and cytosolic 5'(3')-nucleotidases

    Šimák, Ondřej; Pachl, Petr; Fábry, Milan; Buděšínský, Miloš; Jandušík, T.; Hnízda, Aleš; Skleničková, Radka; Petrová, Magdalena; Veverka, Václav; Řezáčová, Pavlína; Brynda, Jiří; Rosenberg, Ivan

    2014-01-01

    Roč. 12, č. 40 (2014), s. 7971-7982. ISSN 1477-0520 R&D Projects: GA ČR GA203/09/0820; GA ČR GA13-24880S; GA ČR GA13-26526S; GA MŠk(CZ) LK11205; GA AV ČR KAN200520801 Institutional support: RVO:61388963 ; RVO:68378050 Keywords : 5'(3')-nucleotidase * structure * inhibition * cdN * mdN * nucleoside * SAR * phosphonic acid Subject RIV: CC - Organic Chemistry Impact factor: 3.562, year: 2014

  18. Inhibition of human thymidine phosphorylase by phosphonate analogues of pyrimidine nucleoside 2’(3’)-phosphates

    Panova, Natalya; Kóšiová, Ivana; Šimák, Ondřej; Petrová, Magdalena; Liboska, Radek; Buděšínský, Miloš; Rejman, Dominik; Rosenberg, Ivan

    Lyon : Université de Lyon, 2010, s. 336-337. [International Roundtable on Nucleosides, Nucleotides and Nucleic Acids. IRT 2010. Lyon (FR), 29.08.2010-03.09.2010] R&D Projects: GA MŠk(CZ) LC06077; GA AV ČR KAN200520801; GA MŠk(CZ) LC06061 Institutional research plan: CEZ:AV0Z40550506 Keywords : human thymidine phosphorylase * phosphorylase inhibition * phosphonate nucleosides Subject RIV: CC - Organic Chemistry http://irt2010.univ-lyon1.fr

  19. In Vivo Modulation of Angiogenic Genes Expression by Acyclic Nucleoside Phosphonates PMEDAP and PMEG

    Otová, B.; Hrdý, J.; Votruba, Ivan; Holý, Antonín

    2009-01-01

    Roč. 29, č. 4 (2009), s. 1295-1302. ISSN 0250-7005 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : PMEDAP * PMEG * proangiogenic genes Subject RIV: CC - Organic Chemistry Impact factor: 1.428, year: 2009

  20. New in vitro method for evaluating antiviral activity of acyclic nucleoside phosphonates against plant viruses

    Špak, Josef; Holý, Antonín; Pavingerová, Daniela; Votruba, Ivan; Špaková, Vlastimila; Petrzik, Karel

    2010-01-01

    Roč. 88, č. 3 (2010), s. 296-303. ISSN 0166-3542 R&D Projects: GA ČR GA522/09/0707 Institutional research plan: CEZ:AV0Z50510513; CEZ:AV0Z40550506 Keywords : Brassica * Chemotherapy * Turnip yellow mosaic virus * Ribavirin Subject RIV: CE - Biochemistry Impact factor: 4.439, year: 2010

  1. Potential role of acyclic nucleoside phosphonates in the treatment of malaria

    Janeba, Zlatko; Hocková, Dana; Keough, D. T.; Guddat, L. W.

    Nerja: -, 2014. [Zing Drug Discovery Conference 2014 /4./. 17.02.2014-20.02.2014, Nerja] R&D Projects: GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : ANPs * prodrugs * malaria Subject RIV: CC - Organic Chemistry

  2. Antimalarial activity of prodrugs of N-branched acyclic nucleoside phosphonate inhibitors of 6-oxopurine phosphoribosyltransferases

    Hocková, Dana; Janeba, Zlatko; Naesens, L.; Edstein, M. D.; Chavchich, M.; Keough, D. T.; Guddat, L. W.

    2015-01-01

    Roč. 23, č. 17 (2015), s. 5502-5510. ISSN 0968-0896 R&D Projects: GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : nucleotide analogues * enzyme inhibitors * malaria * HG(X)PRT * ANP Subject RIV: CC - Organic Chemistry Impact factor: 2.793, year: 2014

  3. Acyclic nucleoside phosphonates containing O-substituted hydroxypyridineamines and diamines as nucleobases

    Otmar, Miroslav; Masojídková, Milena; Holý, Antonín

    Praha : ÚOCHB AV ČR, 2005 - (Hocek, M.), s. 283-285 ISBN 80-86241-25-4. - (Collection Symposium Series. 7). [Chemistry of Nucleic Acid Components /13./. Špindlerův Mlýn (CZ), 03.09.2005-09.09.2005] R&D Projects: GA MŠk(CZ) 1M0508 Grant ostatní: René Descartes Prize 2001(XE) HPAW-2002-100096 Institutional research plan: CEZ:AV0Z40550506 Keywords : pyridine nucleotides * antivirals * nucleophilic aromatic substitution Subject RIV: CC - Organic Chemistry

  4. Chiral analysis of acyclic nucleoside phosphonates-based anti-aids drugs by capillary electrophoresis

    Kašička, Václav; Šolínová, Veronika; Sázelová, Petra; Mikysková, Hana; Jansa, Petr; Krečmerová, Marcela; Holý, Antonín

    2012-01-01

    Roč. 106, - (2012), s604-s604. ISSN 0009-2770. [EuCheMS Chemistry Congress /4./. 26.08.2012-30.08.2012, Prague] R&D Projects: GA MŠk 1M0508; GA ČR(CZ) GA203/08/1428 Institutional research plan: CEZ:AV0Z40550506 Keywords : analytical methods * electrophoresis * enentioselectivity Subject RIV: CC - Organic Chemistry

  5. Acyclic nucleoside phosphonates: a study on cytochrome P450 gene expression

    Nekvindová, J.; Contreras, J. A.; Juvan, P.; Tacer, K. F.; Anzenbacher, P.; Zídek, Zdeněk; Zapletalová, M.; Rozman, D.; Anzenbacherová, E.

    2014-01-01

    Roč. 44, č. 8 (2014), s. 708-715. ISSN 0049-8254 Grant ostatní: GA MŠk(CZ) CZ.1.07/2.3.00/20.0019; GA MŠk(CZ) CZ.1.05/2.1.00/01.003 Institutional support: RVO:68378041 Keywords : induction * drug metabolism * antiviral Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 2.199, year: 2014

  6. Acyclic nucleoside bis-phosphonates as potent inhibitors of 6-oxopurine phosphoribosyltransferases

    Špaček, Petr; Keough, D. T.; Vrbková, Silvie; Slavětínská, Lenka; Janeba, Zlatko; Naesens, L.; Edstein, M. D.; Chavchich, M.; Wang, T. H.; de Jersey, J.; Guddat, L. W.; Hocková, Dana

    Praha : Institute of Organic Chemistry and Biochemistry AS CR, v. v. i, 2014 - (Hocek, M.), s. 375-376 ISBN 978-80-86241-50-0. - (Collection Symposium Series. 14). [Symposium on Chemistry of Nucleic Acid Components /16./. Český Krumlov (CZ), 08.06.2014-13.06.2014] R&D Projects: GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : nucleotide analogues * enzyme inhibitors * Plasmodium Subject RIV: CC - Organic Chemistry

  7. Novel acyclic nucleoside phosphonate analogues with potent anti-hepatitis B virus activities

    Ying, C.; Holý, Antonín; Hocková, Dana; Havlas, Zdeněk; De Clercq, E.; Neyts, J.

    2005-01-01

    Roč. 49, č. 3 (2005), 1177-1180. ISSN 0066-4804 R&D Projects: GA AV ČR(CZ) IBS4055109 Grant ostatní: FWO(BE) G.0267.04 Institutional research plan: CEZ:AV0Z4055905 Keywords : antivirals * hepatitis B * ANP Subject RIV: CC - Organic Chemistry Impact factor: 4.379, year: 2005

  8. Macrophage activation by antiviral acyclic nucleoside phosphonates in dependence on priming immune stimuli

    Zídek, Zdeněk; Franková, Daniela; Holý, Antonín

    2000-01-01

    Roč. 22, č. 12 (2000), s. 1121-1129. ISSN 0192-0561 R&D Projects: GA ČR GA305/00/0048; GA ČR GV203/96/K001 Institutional research plan: CEZ:AV0Z5008914 Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 1.142, year: 2000

  9. The unique impact of microwave irradiation on the chemistry of acyclic nucleoside phosphonates

    Jansa, Petr; Holý, Antonín; Dračínský, Martin; Baszczyňski, Ondřej; Česnek, Michal; Janeba, Zlatko

    Praha : Institute of Organic Chemistry and Biochemistry AS CR, v. v. i., 2011 - (Hocek, M.), s. 347-348 ISBN 978-80-86241-37-1. - (Collection Symposium Series. 12). [Chemistry of Nucleic Acid Components /15./. Český Krumlov (CZ), 05.06.2011-10.06.2011] R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : ANPs * hydrolysis * microwave * Michaelis -Arbuzov reaction * haloalkylphosphonates Subject RIV: CC - Organic Chemistry

  10. Synthesis of conformationally locked L-deoxythreosyl phosphonate nucleosides built on a bicyclo[3.1.0]hexane template.

    Saneyoshi, Hisao; Deschamps, Jeffrey R; Marquez, Victor E

    2010-11-19

    Two conformationally locked versions of l-deoxythreosyl phosphonate nucleosides (2 and 3) were synthesized to investigate the preference of HIV reverse transcriptase for a conformation displaying either a fully diaxial or fully diequatorial disposition of substituents. Synthesis of the enantiomeric 4-(6-amino-9H-purin-9-yl)bicyclo[3.1.0]hexan-2-ol carbocyclic nucleoside precursors (diaxially disposed) proceeded straightforwardly from commercially available (1R,4S)-4-hydroxy-2-cyclopent-2-enyl-1-yl acetate employing a hydroxyl-directed Simmons-Smith cyclopropanation that culminated with a Mitsunobu coupling of the purine base. For the more complicated 1-(6-amino-9H-purin-9-yl)bicyclo[3.1.0]hexan-3-ol carbocyclic nucleoside precursors (diequatorially disposed), the obligatory linear approach required the syntheses of key 1-aminobicyclo[3.1.0.]hexan-3-yl benzoate precursors that were assembled via the amide variant of the Kulinkovich reaction involving the intramolecular cyclopropanation of a substituted δ-vinylamide. Completion of the purine ring was achieved by conventional approaches but with much improved yields through the use of a microwave reactor. The syntheses of the phosphonates and the corresponding diphosphates were achieved by conventional means. None of the diphosphates, which were supposed to act as nucleoside triphosphate mimics, could compete with dATP even when present in a 10-fold excess. PMID:20964394

  11. Acyclic Nucleoside Phosphonates Containing a Second Phosphonate Group Are Potent Inhibitors of 6-Oxopurine Phosphoribosyltransferases and Have Antimalarial Activity

    Keough, D. T.; Špaček, Petr; Hocková, Dana; Tichý, Tomáš; Vrbková, S.; Slavětínská, Lenka; Janeba, Zlatko; Naesens, L.; Edstein, M. D.; Chavchich, M.; Wang, T. H.; de Jersey, J.; Guddat, L. W.

    2013-01-01

    Roč. 56, č. 6 (2013), s. 2513-2526. ISSN 0022-2623 R&D Projects: GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : enzyme inhibitors * ANPs * malaria * bisphosphonates Subject RIV: CC - Organic Chemistry Impact factor: 5.480, year: 2013

  12. Acyclic nucleoside phosphonates containing a second phosphonate group as potent inhibitors of 6-oxopurine phosphoribosyltransferases with antimalarial activity

    Špaček, Petr; Keough, D. T.; Hocková, Dana; Tichý, Tomáš; Vrbková, Silvie; Slavětínská, Lenka; Janeba, Zlatko; Naesens, L.; Edstein, M. D.; Chavchich, M.; Wang, T.; de Jersey, J.; Guddat, L. W.

    Marseille : -, 2013. s. 183-183. [ESOC 2013. European Symposium on Organic Chemistry /18./. 07.07.2013-12.07.2013, Marseille] R&D Projects: GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : nucleotide analogues * enzyme inhibitors * Plasmodium Subject RIV: CC - Organic Chemistry

  13. Acyclic nucleoside phosphonates containing a second phosphonate group as potent inhibitors of 6-oxopurine phosphoribosyltransferases with antimalarial activity

    Špaček, Petr; Keough, D. T.; Janeba, Zlatko; Edstein, M. D.; Chavchich, M.; Wang, T. H.; Guddat, L. W.; Hocková, Dana

    Santa Barbara : International Society of Heterocyclic Chemistry, 2015. 0166. [International Society of Heterocyclic Chemistry Congress /25./. 23.08.2015-28.08.2015, Santa Barbara] Institutional support: RVO:61388963 Keywords : nucleotide analogues * enzyme inhibitors * Plasmodium Subject RIV: CC - Organic Chemistry

  14. Design and synthesis of novel 5-substituted acyclic pyrimidine nucleosides as potent and selective inhibitors of hepatitis B virus.

    Kumar, Rakesh; Nath, Mahendra; Tyrrell, D Lorne J

    2002-05-01

    A novel class of 5-substituted acyclic pyrimidine nucleosides, 1-[(2-hydroxyethoxy)methyl]-5-(1-azidovinyl)uracil (9a), 1-[(2-hydroxy-1-(hydroxymethyl)ethoxy)methyl]-5-(1-azidovinyl)uracil (9b), and 1-[4-hydroxy-3-(hydroxymethyl)-1-butyl]-5-(1-azidovinyl)uracil (9c), were synthesized by regiospecific addition of bromine azide to the 5-vinyl substituent of the respective 5-vinyluracils (2a-c) followed by treatment of the obtained 5-(1-azido-2-bromoethyl) compounds (3a-c) with t-BuOK, to affect the base-catalyzed elimination of HBr. Thermal decomposition of 9b and 9c at 110 degrees C in dioxane yielded corresponding 5-[2-(1-azirinyl)]uracil analogues (10b,c). The 5-(1-azidovinyl)uracil derivatives 9a-c were found to exhibit potent and selective in vitro anti-HBV activity against duck hepatitis B virus (DHBV) infected primary duck hepatocytes at low concentrations (EC(50) = 0.01-0.1 microg/mL range). The most active anti-DHBV agent (9c), possessing a [4-hydroxy-3-(hydroxymethyl)-1-butyl] substituent at N-1, exhibited an activity (EC(50) of 0.01-0.05 microg/mL) comparable to that of reference compound (-)-beta-L-2',3'-dideoxy-3'-thiacytidine (3-TC) (EC(50) = 0.01-0.05 microg/mL). In contrast, related 5-[2-(1-azirinyl)]uracil analogues (10b,c) were devoid of anti-DHBV activity, indicating that an acyclic side chain at C-5 position of the pyrimidine ring is essential for anti-HBV activity. The pyrimidine nucleosides (9a-c, 10b,c) exhibited no cytotoxic activity against a panel of 60 human cancer cell lines. All of the compounds investigated did not show any detectable toxicity to several stationary and proliferating host cell lines or to mitogen stimulated proliferating human T lymphocytes, up to the highest concentration tested. PMID:11985471

  15. Alternative synthesis of 9-{3-[(diisopropoxyphosphoryl)-methoxy]-2-hydroxypropyl}adenine and its free phosphonates substituted at the C-8 position of purine base

    Janeba, Zlatko; Masojídková, Milena; Holý, Antonín

    2010-01-01

    Roč. 75, č. 3 (2010), s. 371-381. ISSN 0010-0765 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * HPMPA * nucleophilic substitution * intramolecular cyclization Subject RIV: CC - Organic Chemistry Impact factor: 0.853, year: 2010

  16. Pyrimidine acyclic nucleotide analogues with aromatic substituents in C-5 position

    Krečmerová, Marcela; Holý, Antonín; Masojídková, Milena

    2007-01-01

    Roč. 72, č. 7 (2007), s. 927-951. ISSN 0010-0765 R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Grant ostatní: René Descartes Prize(XE) HPAW-2002-100096 Institutional research plan: CEZ:AV0Z40550506 Keywords : antivirals * acyclic nucleoside phosphonates * 5-phenyluracil * HPMPU * HPMPC Subject RIV: CC - Organic Chemistry Impact factor: 0.879, year: 2007

  17. Amido tyrosine esters: a promising new approach to antiviral nucleoside phosphonate prodrugs

    McKenna, Ch. E.; Kashemirov, B. A.; Zakharova, V. M.; Krylov, I. S.; Williams, M.; Krečmerová, Marcela; Drach, J. C.; Hilfinger, J. M.

    Elsevier. Roč. 90, - (2011), A23-A24. ISSN 0166-3542. [International Conference on Antiviral Research (ICAR) /24./. 08.05.2011-11.05.2011, Sofia] R&D Projects: GA MŠk(CZ) ME10040 Institutional research plan: CEZ:AV0Z40550506 Keywords : antiviral activity * ANP * phosphonates * oral bioavailability * tyrosine * ester prodrugs Subject RIV: CC - Organic Chemistry

  18. Prolinol-based nucleoside phosphonic acids: new isosteric conformationally flexible nucleotide analogues

    Vaněk, Václav; Buděšínský, Miloš; Rinnová, Markéta; Rosenberg, Ivan

    2009-01-01

    Roč. 65, č. 4 (2009), s. 862-876. ISSN 0040-4020 R&D Projects: GA ČR GA203/05/0827; GA MŠk(CZ) LC06077; GA MŠk LC512; GA MŠk(CZ) LC06061 Institutional research plan: CEZ:AV0Z40550506 Keywords : nucleotide analogues * phosphonates * prolinol derivatives * N-alkylation Subject RIV: CC - Organic Chemistry Impact factor: 3.219, year: 2009

  19. Antiviral activity of acyclic nucleoside phosphonates PMEA, (S)-HPMPC, PMEDAP and ribavirin against Cauliflower mosaic virus in Brassica pekinensis

    Špak, Josef; Votruba, Ivan; Pavingerová, Daniela; Holý, Antonín; Špaková, Vlastimila; Petrzik, Karel

    2012-01-01

    Roč. 10, č. 1 (2012), s. 63-68. ISSN 0167-6857 R&D Projects: GA ČR GA522/09/0707 Institutional research plan: CEZ:AV0Z50510513; CEZ:AV0Z40550506 Keywords : Caulimovirus * Chemotherapy * Pararetrovirus * dsDNA Subject RIV: EE - Microbiology, Virology Impact factor: 3.633, year: 2012

  20. Acyclic nucleoside phosphonates with branched 2-(2-phosphonoethoxy)ethyl chain: efficient synthesis and biological activity

    Hocková, Dana; Holý, Antonín; Andrei, G.; Snoeck, R.; Balzarini, J.; Keough, D. T.; de Jersey, J.; Guddat, L. W.

    Crete : University of Crete, 2011. [ESOC 2011. European Symposium on Organic Chemistry /17./. 10.07.2011-15.07.2011, Crete] R&D Projects: GA MŠk 1M0508; GA ČR GAP207/11/0108 Institutional research plan: CEZ:AV0Z40550506 Keywords : nucleotide analogues * antiviral activity * antiplasmodial activity Subject RIV: CC - Organic Chemistry

  1. Aza-acyclic Nucleoside Phosphonates Containing a Second Phosphonate Group As Inhibitors of the Human, Plasmodium falciparum and vivax 6-Oxopurine Phosphoribosyltransferases and Their Prodrugs As Antimalarial Agents

    Keough, D. T.; Hocková, Dana; Janeba, Zlatko; Wang, T. H.; Naesens, L.; Edstein, M. D.; Chavchich, M.; Guddat, L. W.

    2015-01-01

    Roč. 58, č. 2 (2015), s. 827-846. ISSN 0022-2623 R&D Projects: GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : enzyme inhibitors * ANPs * Plasmodium * malaria Subject RIV: CC - Organic Chemistry Impact factor: 5.447, year: 2014

  2. Inhibition of human thymidine phosphorylase by conformationally constrained pyrimidine nucleoside phosphonic acids and their "open-structure" isosteres

    Kóšiová, Ivana; Šimák, Ondřej; Panova, Natalya; Buděšínský, Miloš; Petrová, Magdalena; Rejman, Dominik; Liboska, Radek; Páv, Ondřej; Rosenberg, Ivan

    2014-01-01

    Roč. 74, Mar 3 (2014), s. 145-168. ISSN 0223-5234 R&D Projects: GA ČR GA203/09/0820; GA ČR GA202/09/0193; GA ČR GA13-24880S; GA ČR GA13-26526S Institutional support: RVO:61388963 Keywords : phosphonate * conformationally constrained nucleotide analog * human thymidine phosphorylase * PBMC * bi-substrate-like inhibitor * Michael addition Subject RIV: CC - Organic Chemistry Impact factor: 3.447, year: 2014

  3. Piperidine nucleosides and nucleotides

    Kovačková, Soňa; Dračínský, Martin; Rosenberg, Ivan; Rejman, Dominik

    Lyon : Université de Lyon, 2010, s. 315-316. [International Roundtable on Nucleosides, Nucleotides and Nucleic Acids. IRT 2010. Lyon (FR), 29.08.2010-03.09.2010] Institutional research plan: CEZ:AV0Z40550506 Keywords : phosphonate analogs * piperidine nucleosides * piperidine nucleotides Subject RIV: CC - Organic Chemistry http://irt2010.univ-lyon1.fr

  4. Synthesis of Novel N-Branched Acyclic Nucleoside Phosphonates As Potent and Selective Inhibitors of Human, Plasmodium falciparum and Plasmodium vivax 6-Oxopurine Phosphoribosyltransferases

    Hocková, Dana; Keough, D. T.; Janeba, Zlatko; Wang, T.; de Jersey, J.; Guddat, L. W.

    2012-01-01

    Roč. 55, č. 13 (2012), s. 6209-6223. ISSN 0022-2623 R&D Projects: GA ČR GAP207/11/0108; GA MŠk 1M0508 Grant ostatní: NHMRC(AU) 569703; NHMRC(AU) 1030353 Institutional support: RVO:61388963 Keywords : enzyme inhibitors * aza-ANPs * malaria Subject RIV: CC - Organic Chemistry Impact factor: 5.614, year: 2012

  5. 6-[2-(Phosphonomethoxy)alkoxy]-2,4-diaminopyrimidines: A new class of acyclic pyrimidine nucleoside phosphonates with antiviral activity

    Balzarini, J.; Pannecouque, C.; Naesens, L.; Andrei, G.; Snoeck, R.; De Clercq, E.; Hocková, Dana; Holý, Antonín

    2004-01-01

    Roč. 23, 8/9 (2004), s. 1321-1327. ISSN 1525-7770 R&D Projects: GA AV ČR IBS4055109 Grant ostatní: GWOV(BE) G.0104.98; GOA (BE) 00/12 Institutional research plan: CEZ:AV0Z4055905 Keywords : herpesviruses * poxviruses * hepadnaviruses Subject RIV: CC - Organic Chemistry Impact factor: 0.429, year: 2004

  6. New Anti-malarial Drug Leads: N-Branched Acyclic Nucleoside Phosphonates as Inhibitors of the Plasmodium falciparum and vivax 6-Oxopurine Phosphoribosyltransferases

    Hocková, Dana; Keough, D. T.; Janeba, Zlatko; Naesens, L.; Edstein, M. D.; Chavchich, M.; Wang, T. H.; de Jersey, J.; Guddat, L. W.

    Istanbul : IUPAC, 2013. s. 1629-1629. [World Chemistry Congress /44./. 11.08.2013-16.08.2013, Istanbul] R&D Projects: GA ČR GAP207/11/0108 Grant ostatní: NHMRC(AU) 1030353 Institutional support: RVO:61388963 Keywords : nucleotide analogues * enzyme inhibitors * Plasmodium Subject RIV: CC - Organic Chemistry

  7. First Crystal Structures of Mycobacterium tuberculosis 6-Oxopurine Phosphoribosyltransferase: Complexes with GMP and Pyrophosphate and with Acyclic Nucleoside Phosphonates Whose Prodrugs Have Antituberculosis Activity

    Eng, W. S.; Hocková, Dana; Špaček, Petr; Janeba, Zlatko; West, N. P.; Woods, K.; Naesens, L. M. J.; Keough, D. T.; Guddat, L. W.

    2015-01-01

    Roč. 58, č. 11 (2015), s. 4822-4838. ISSN 0022-2623 R&D Projects: GA ČR GAP207/11/0108; GA MV VG20102015046 Institutional support: RVO:61388963 Keywords : enzyme inhibitors * nucleotide analogues * tuberculosis * crystal structures Subject RIV: CC - Organic Chemistry Impact factor: 5.447, year: 2014

  8. Piperidine nucleosides and nucleotides

    Kovačková, Soňa; Pačes, Ondřej; Dračínský, Martin; Rosenberg, Ivan; Rejman, Dominik

    Manchester : University of Manchester, 2009. s. 50-50. [Nucleic Acids at the Chemistry - Biology Interface. 07.09.2009-08.09.2009, Manchester] R&D Projects: GA MZd NR9138; GA MŠk 2B06065 Institutional research plan: CEZ:AV0Z40550506 Keywords : phosphonate * piperidine nucleosides * nucleotides Subject RIV: CC - Organic Chemistry

  9. Structural diversity of nucleoside phosphonic acids as a key factor in the discovery of potent inhibitors of rat T-cell lymphoma thymidine phosphorylase

    Kočalka, Petr; Rejman, Dominik; Vaněk, Václav; Rinnová, Markéta; Tomečková, Ivana; Králíková, Šárka; Petrová, Magdalena; Páv, Ondřej; Pohl, Radek; Buděšínský, Miloš; Liboska, Radek; Točík, Zdeněk; Panova, Natalya; Votruba, Ivan; Rosenberg, Ivan

    2010-01-01

    Roč. 20, č. 3 (2010), s. 862-865. ISSN 0960-894X R&D Projects: GA ČR GA203/09/0820; GA ČR GA202/09/0193; GA MŠk(CZ) LC06061; GA MŠk(CZ) LC06077; GA MŠk 2B06065; GA AV ČR KAN200520801; GA AV ČR 1QS400550501; GA MZd NR9138 Institutional research plan: CEZ:AV0Z40550506 Keywords : phosphonate nucleotides * pyrrolidine * thymidine phosphorylase Subject RIV: CC - Organic Chemistry Impact factor: 2.661, year: 2010

  10. Piperidine nucleosides and nucleotides

    Kovačková, Soňa; Pačes, Ondřej; Dračínský, Martin; Rosenberg, Ivan; Rejman, Dominik

    -, č. 52 (2008), s. 587-587. ISSN 0261-3166. [Joint Symposium of the International Roundtable on Nucleosides, Nucleotides and Nucleic Acids /18./ and the International Symposium on Nucleic Acid Chemistry /35./. Kyoto, 08.09.2008-12.09.2008] R&D Projects: GA MŠk(CZ) LC06077; GA MŠk 2B06065; GA MŠk LC512 Grant ostatní: GA MZd(CZ) NR9138 Institutional research plan: CEZ:AV0Z40550506 Keywords : piperidine * nucleosidation * phosphonate Subject RIV: CC - Organic Chemistry

  11. Counting acyclic hypergraphs

    2001-01-01

    Acyclic hypergraphs are analogues of forests in graphs. They arevery useful in the design of databases. The number of distinct acyclic uniform hypergraphs with n labeled vertices is studied. With the aid of the principle of inclusion-exclusion, two formulas are presented. One is the explicit formula for strict (d)-connected acyclic hypergraphs, the other is the recurrence formula for linear acyclic hypergraphs.

  12. Acyclic social welfare

    Lahiri, Somdeb

    2009-01-01

    In this paper we show that if the Pareto relation is acyclic then the set of all Pareto optimal social states coincides with chosen social states of acyclic Paretian social welfare relations. Subsequently we show that given an acyclic Paretian social welfare relations the set of all social states chosen by it coincides with the set of all states chosen by strict Paretian extensions whose strict extension is the given social welfare relation.

  13. NMR study of conformationally restricted acylic phosphonate nucleotides

    Poštová Slavětínská, Lenka; Pohl, Radek; Rejman, Dominik

    Hersonissos : -, 2013. s. 609-609. [EUROMAR 2013. A European Magnetic Resonance Meeting. 30.06.2013-05.07.2013, Hersonissos] R&D Projects: GA ČR GA13-24880S Institutional support: RVO:61388963 Keywords : acyclic phosphonate nucleotides * conformation * pyrrolidine ring * NMR spectra * PSEUROT program * pD dependence * molecular modeling Subject RIV: CB - Analytical Chemistry, Separation

  14. Chiral analysis of anti-acquired immunodeficiency syndrome drug, 9-(R)-[2-(phosphonomethoxy)propyl]adenine (tenofovir), and related antiviral acyclic nucleoside phosphonates by CE using beta-CD as chiral selector

    Šolínová, Veronika; Kašička, Václav; Sázelová, Petra; Holý, Antonín

    2009-01-01

    Roč. 30, č. 12 (2009), s. 2245-2254. ISSN 0173-0835 R&D Projects: GA ČR(CZ) GA203/06/1044; GA ČR(CZ) GA203/08/1428; GA AV ČR 1QS400550501; GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : antiviral drugs * capillary electrophoresis * enantioseparation Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.077, year: 2009

  15. Subquivers of mutation-acyclic quivers are mutation-acyclic

    Warkentin, Matthias

    2011-01-01

    Quiver mutation plays a crucial role in the definition of cluster algebras by Fomin and Zelevinsky. It induces an equivalence relation on the set of all quivers without loops and two-cycles. A quiver is called mutation-acyclic if it is mutation-equivalent to an acyclic quiver. The aim of this note is to show that full subquivers of mutation-acyclic quivers are mutation-acyclic.

  16. Enumeration of Maximum Acyclic Hypergraphs

    Jian-fang Wang; Hai-zhu Li

    2002-01-01

    Acyclic hypergraphs are analogues of forests in graphs. They are very useful in the design of databases. In this article, the maximum size of an acyclic hypergraph is determined and the number of maximum r-uniform acyclic hypergraphs of order n is shown to be ( n t-1 )(n(r-1)-r2 +2r)n-r-1.

  17. Nucleoside Sensing

    Thomas Schrader; Frank-Gerrit Klärner; Michael Fokkens

    2006-01-01

    A rigid molecular clip comprising bisphosphonate binding sites and aromatic sidewalls forming an electron-rich cavity is able to distinguish between nucleosides and nucleotides in aqueous solution. Neutral nucleosides as well as antibiotics derived thereof are drawn into the unpolar interior of the cleft and lead to substantial upfield-shifts in the 1H NMR spectrum. Nucleoside drugs can therefore be detected with high selectivity in the presence of their phosphorylated pendants or nucleic acids.

  18. An enzymatic glycosylation of nucleoside analogues using beta-galactosidase from Escherichia coli

    Blažek, Jiří; Jansa, Petr; Baszczyňski, Ondřej; Kaiser, Martin Maxmilian; Otmar, Miroslav; Krečmerová, Marcela; Dračínský, Martin; Holý, Antonín; Králová, B.

    2012-01-01

    Roč. 20, č. 9 (2012), s. 3111-3118. ISSN 0968-0896 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : glycosylation * galactosylation * beta-galactosidase * enzymatic synthesis * nucleoside * acyclic nucleoside analogues Subject RIV: CC - Organic Chemistry Impact factor: 2.903, year: 2012

  19. ON ACYCLIC AND CYCLIC HYPERGRAPHS

    LI Haizhu; WANG Jianfang

    2002-01-01

    So far, the acyclic hypergraph has two different definitions. One is based onthe cyclomatic number of the hypergraph, whereas the other arises from the acyclic schemaof the relational database in the computer science. In this paper, it is first proved thatthese two definitions coincide with each other completely. Then we prove that a hypergraphH is not acyclic, or cyclic, if and only if it contains a special partial hypergraph namedhypercircuit. In addition, we show that H has l(H) different hypercircuits, where l(H) isa parameter used to decide whether H is acyclic or cyclic.

  20. Synthesis of (Purin-6-yl)methylphosphonate Bases and Nucleosides

    Hasník, Zbyněk; Pohl, Radek; Hocek, Michal

    2010-01-01

    Roč. 51, č. 18 (2010), s. 2464-2466. ISSN 0040-4039 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : purines * nucleosides * phosphonates * cross-coupling Subject RIV: CC - Organic Chemistry Impact factor: 2.618, year: 2010

  1. Chiral phosphonate internucleotide linkage: A promising modification for chimeric oligonucleotides?

    Liboska, Radek; Petrová, Magdalena; Pohl, Radek; Buděšínský, Miloš; Hurychová, Vladimíra; Rosenberg, Ivan

    -, č. 52 (2008), s. 317-318. ISSN 0261-3166. [Joint Symposium of the International Roundtable on Nucleosides, Nucleotides and Nucleic Acids /18./ and the International Symposium on Nucleic Acid Chemistry /35./. Kyoto, 08.09.2008-12.09.2008] R&D Projects: GA MŠk(CZ) LC06061 Grant ostatní: EMIL-FP6(XE) 503569 Institutional research plan: CEZ:AV0Z40550506 Keywords : oligonucleotide phosphonate Subject RIV: CC - Organic Chemistry

  2. Acyclic nucleoside bisphosphonates as inhibitors of 6-oxopurine phosphoribosyltransferases

    Hocková, Dana; Keough, D. T.; Špaček, Petr; Janeba, Zlatko; Naesens, L.; Edstein, M. D.; Chavchich, M.; Wang, T. H.; de Jersey, J.; Guddat, L. W.

    Kanagawa : Kanagawa University, 2013. P004-P004. [ISNAC 2013. The International Symposium on Nucleic Acid Chemistry /40./. 13.11.2013-15.11.2013, Yokohama] R&D Projects: GA ČR GAP207/11/0108 Grant ostatní: NHMRC(AU) 1030353 Institutional support: RVO:61388963 Keywords : nucleotide analogues * enzyme inhibitors * plasmodium Subject RIV: CC - Organic Chemistry

  3. Backdoors to Acyclic SAT

    Gaspers, Serge

    2011-01-01

    Backdoor sets, a notion introduced by Williams et al. in 2003, are certain sets of "key" variables of a CNF formula F that make it easy to solve the formula; by assigning truth values to the variables in a backdoor set, the formula gets reduced to one or several polynomial-time solvable formulas. More specifically, a weak backdoor set of F is a set X of variables such that there exits a truth assignment t to X that reduces F to a satisfiable formula F[t] that belongs to a polynomial-time decidable base class C. A strong backdoor set is a set X of variables such that for all assignments t to X, the reduced formula F[t] belongs to C. We study the problem of finding backdoor sets of size at most k with respect to the base class of CNF formulas with acyclic incidence graphs, taking k as the parameter. We show that 1. the detection of weak backdoor sets is W[2]-hard in general but fixed-parameter tractable for r-CNF formulas, for any fixed r>=3, and 2. the detection of strong backdoor sets is fixed-parameter appro...

  4. Some inequalities for orderings of acyclic digraphs

    Bier, Thomas

    2011-01-01

    For any acyclic ordering $g$ of a finite acyclic digraph $D$ we obtain a lower bound inequality for the inner product of its $e-$vector and $g.$ Here the $e-$vector is defined to be the difference of the indegree and the outdegree of the underlying acyclic digraph. This gives a lower bound on the functional $ T_e(f) = ,$ defined on the set of all acyclic orderings of $D.$ The class of acyclic digraphs which admit an acyclic ordering attaining the lower bound is determined as the class of posets of order dimension two.

  5. Convex sets in acyclic digraphs

    Balister, P; Gutin, G

    2007-01-01

    A non-empty set $X$ of vertices of an acyclic digraph is called connected if the underlying undirected graph induced by $X$ is connected and it is called convex if no two vertices of $X$ are connected by a directed path in which some vertices are not in $X$. The set of convex sets (connected convex sets) of an acyclic digraph $D$ is denoted by $\\sco(D)$ ($\\scc(D)$) and its size by $\\co(D)$ ($\\cc(D)$). Gutin, Johnstone, Reddington, Scott, Soleimanfallah, and Yeo (Proc. ACiD'07) conjectured that the sum of the sizes of all (connected) convex sets in $D$ equals $\\Theta(n \\cdot \\co(D))$ ($\\Theta(n \\cdot \\cc(D))$) where $n$ is the order of $D$. In this paper we exhibit a family of connected acyclic digraphs with $\\sum_{C\\in \\sco(D)}|C| = o(n\\cdot \\co(D))$ and $\\sum_{C\\in \\scc(D)}|C| = o(n\\cdot \\cc(D))$. We also show that the number of connected convex sets of order $k$ in any connected acyclic digraph of order $n$ is at least $n-k+1$. This is a strengthening of a theorem by Gutin and Yeo.

  6. N-Phosphonocarbonylpyrrolidine Derivatives of Guanine: A New Class of Bi-Substrate Inhibitors of Human Purine Nucleoside Phosphorylase

    Rejman, Dominik; Panova, Natalya; Klener, P.; Maswabi, B.; Pohl, Radek; Rosenberg, Ivan

    2012-01-01

    Roč. 55, č. 4 (2012), s. 1612-1621. ISSN 0022-2623 R&D Projects: GA MŠk 2B06065; GA MŠk(CZ) LC06077; GA AV ČR KAN200520801 Institutional research plan: CEZ:AV0Z40550506 Keywords : nucleoside * phosphonic acid * pyrrolidine * purine nucleoside Subject RIV: CC - Organic Chemistry Impact factor: 5.614, year: 2012

  7. [Amino(iminiomethyl]phosphonate

    Ting-Hai Yang

    2010-09-01

    Full Text Available The title compound, CH5N2O3P, exists as a zwitterion. The N atom of the imino group is protonated and the phosphonic acid group is deprotonated. The molecular geometry about the central C atom of this zwitterionic species was found to be strictly planar with the sum of the three angles about C being precisely 360°. In the crystal, the molecules are interlinked by O—H...O and N—H...O hydrogen-bonding interactions, forming a three-dimensional supramolecular network structure.

  8. Homochiral metal phosphonate nanotubes.

    Liu, Xun-Gao; Bao, Song-Song; Huang, Jian; Otsubo, Kazuya; Feng, Jian-Shen; Ren, Min; Hu, Feng-Chun; Sun, Zhihu; Zheng, Li-Min; Wei, Shiqiang; Kitagawa, Hiroshi

    2015-10-21

    A new type of homochiral metal-organic nanotubular structures based on metal phosphonates are reported, namely, (R)- or (S)-[M(pemp)(H2O)2][M = Co(II) (1), Ni(II) (2)] [pemp(2-) = (R)- or (S)-(1-phenylethylamino)methylphosphonate]. In these compounds, the tube-walls are purely inorganic, composed of metal ions and O-P-O bridges. The cavity of the nanotube is hydrophilic with one coordination water pointing towards the center, while the outer periphery of the nanotube is hydrophobic, decorated by the phenylethyl groups of pemp(2-). The thermal stabilities, adsorption and proton conductivity properties are investigated. PMID:26324662

  9. Polymerization of the cyclic pyrophosphates of nucleosides and their analogues

    Tohidi, Mahrokh; Orgel, Leslie E.

    1990-01-01

    When 2-prime-deoxythymidine 3-prime, 5-prime-cyclic diphosphate, or the cyclic pyrophosphates of the acyclic nucleoside analogs II and IV are heated to 65-85 C in the presence of imidazole, oligomers with lengths up to 20-30 are formed in excellent yield. This reaction provides a useful source of oligomers for use as templates in aqueous condensation reactions. In the absence of evidence to the contrary, it is assumed that the oligomers are atactic. The potential significance of this reaction in prebiotic chemistry is discussed.

  10. Algorithms for Junctions in Directed Acyclic Graphs

    Ferreira, Carlos Eduardo

    2012-01-01

    Given a pair of distinct vertices u, v in a graph G, we say that s is a junction of u, v if there are in G internally vertex disjoint directed paths from s to u and from s to v. We show how to characterize junctions in directed acyclic graphs. We also consider the two problems in the following and derive efficient algorithms to solve them. Given a directed acyclic graph G and a vertex s in G, how can we find all pairs of vertices of G such that s is a junction of them? And given a directed acyclic graph G and k pairs of vertices of G, how can we preprocess G such that all junctions of k given pairs of vertices could be listed quickly? All junctions of k pairs problem arises in an application in Anthropology and we apply our algorithm to find such junctions on kinship networks of some brazilian indian ethnic groups.

  11. The Algebra of Directed Acyclic Graphs

    Fiore, Marcelo; Campos, Marco Devesas

    2013-01-01

    We give an algebraic presentation of directed acyclic graph structure, introducing a symmetric monoidal equational theory whose free PROP we characterise as that of finite abstract dags with input/output interfaces. Our development provides an initial-algebra semantics for dag structure.

  12. Categorification of acyclic cluster algebras: an introduction

    Keller, Bernhard

    2008-01-01

    This is a concise introduction to Fomin-Zelevinsky's cluster algebras and their links with the representation theory of quivers in the acyclic case. We review the definition of cluster algebras (geometric, without coefficients), construct the cluster category and present the bijection between cluster variables and rigid indecomposable objects of the cluster category.

  13. Removal and Recovery of Phosphonate Antiscalants

    Boels, L.

    2012-01-01

    In reverse osmosis (RO) desalination processes, the use of phosphonates prevents scaling, thus allowing for a higher product water recovery, which increases the efficiency of the process. However, a major concern associated with their use in RO desalination is the high cost and environmental impacts associated with the discharge of the waste brine or membrane concentrate containing phosphonates. Therefore, technologies are needed that can remove and recover phosphonate antiscalants from membr...

  14. 2’- and 5’-Phosphonate oligoadenylates: Novel effectors of RNase L

    Páv, Ondřej; Panova, Natalya; Snášel, Jan; Rosenberg, Ivan

    Lyon : Université de Lyon, 2010, s. 197-198. [International Roundtable on Nucleosides, Nucleotides and Nucleic Acids. IRT 2010. Lyon (FR), 29.08.2010-03.09.2010] R&D Projects: GA MŠk(CZ) LC06077; GA MŠk(CZ) LC06061; GA AV ČR KAN200520801 Institutional research plan: CEZ:AV0Z40550506 Keywords : phosphonate oligonucleotides * RNase L * oligoadenylate analogs Subject RIV: CC - Organic Chemistry http://irt2010.univ-lyon1.fr

  15. 3000 Horsepower super conductive field acyclic motor

    A 3000 hp acyclic motor was assembled and tested utilizing superconducting field coils. The magnet assembly is designed as a quadrupole magnet, utilizing a multifilamentary niobium titanium superconductor. Each magnet coil is 18 inches in diameter and 10 inches long, and operates at rated current of 200 amperes, providing 5.8 tesla in the bore of the coils in the motor configuration. The average winding current density is 10,600 A/cm2. The acyclic motor is of a drum-type design with liquid metal current collectors, and is designed to model full-scale machinery for ship propulsion applications. Laboratory test data verified the electrical and electromagnetic design to be within three percent of the calculated values

  16. Acyclic 6-choosability of planar graphs without adjacent short cycles

    WANG WeiFan; ZHANG Ge; CHEN Min

    2014-01-01

    A proper vertex coloring of a graph G is acyclic if G contains no bicolored cycles.Given a list assignment L={L(v)|v∈V}of G,we say that G is acyclically L-colorable if there exists a proper acyclic coloringπof G such thatπ(v)∈L(v)for all v∈V.If G is acyclically L-colorable for any list assignment L with|L(v)|k for all v∈V(G),then G is acyclically k-choosable.In this paper,we prove that every planar graph G is acyclically 6-choosable if G does not contain 4-cycles adjacent to i-cycles for each i∈{3,4,5,6}.This improves the result by Wang and Chen(2009).

  17. Acyclic Edge Coloring of Planar Graphs without Adjacent Triangles

    Dezheng XIE; Yanqing WU

    2012-01-01

    An acyclic edge coloring of a graph G is a proper edge coloring such that there are no bichromatic cycles.The acyclic edge chromatic number of a graph G is the minimum number k such that there exists an acyclic edge coloring using k colors and is denoted by x'a(G).In this paper we prove that x'a(G)≤ Δ(G)+ 5 for planar graphs G without adjacent triangles.

  18. Synthesis of novel castor oil phosphonates

    Castor oil has served as a versatile hydroxy fatty acid (HFA); its principle component, ricinoleic acid, can be isolated from castor oil and has been modified extensively for a number of applications. Additionally, phosphonates and their corresponding phosphonic acids are a functional moiety that ha...

  19. Conformational evaluation of labeled C3'-O-P-13CH2-O-C4'' phosphonate internucleotide linkage, a phosphodiester isostere

    Točík, Zdeněk; Buděšínský, Miloš; Barvík Jr., I.; Rosenberg, Ivan

    2009-01-01

    Roč. 91, č. 7 (2009), s. 514-529. ISSN 0006-3525 R&D Projects: GA AV ČR KAN200520801; GA MŠk(CZ) LC06061; GA MŠk(CZ) LC06077 Institutional research plan: CEZ:AV0Z40550506 Keywords : nucleoside phosphonate * 13C labeling * NMR Subject RIV: CC - Organic Chemistry Impact factor: 2.605, year: 2009

  20. On the stereochemistry of C3'-O-P-CH2-O-C4'' phosphonate internucleotide bond, a phosphate isostere

    Točík, Zdeněk; Buděšínský, Miloš; Barvík Jr., I.; Rosenberg, Ivan

    -, č. 52 (2008), s. 427-428. ISSN 0261-3166. [Joint Symposium of the International Roundtable on Nucleosides, Nucleotides and Nucleic Acids /18./ and the International Symposium on Nucleic Acid Chemistry /35./. Kyoto, 08.09.2008-12.09.2008] R&D Projects: GA MŠk(CZ) LC06061 Institutional research plan: CEZ:AV0Z40550506 Keywords : phosphonate oligonucleotide stereochemistry Subject RIV: CC - Organic Chemistry

  1. On network coding for acyclic networks with delays

    Prasad, K

    2011-01-01

    Problems related to network coding for acyclic, instantaneous networks (where the edges of the acyclic graph representing the network are assumed to have zero-delay) have been extensively dealt with in the recent past. The most prominent of these problems include (a) the existence of network codes that achieve maximum rate of transmission, (b) efficient network code constructions, and (c) field size issues. In practice, however, networks have transmission delays. In network coding theory, such networks with transmission delays are generally abstracted by assuming that their edges have integer delays. Note that using enough memory at the nodes of an acyclic network with integer delays can effectively simulate instantaneous behavior, which is probably why only acyclic instantaneous networks have been primarily focused on thus far. In this work, we elaborate on issues ((a), (b) and (c) above) related to network coding for acyclic networks with integer delays, which have till now been overlooked. We show that the...

  2. Bayesian Discovery of Linear Acyclic Causal Models

    Hoyer, Patrik O

    2012-01-01

    Methods for automated discovery of causal relationships from non-interventional data have received much attention recently. A widely used and well understood model family is given by linear acyclic causal models (recursive structural equation models). For Gaussian data both constraint-based methods (Spirtes et al., 1993; Pearl, 2000) (which output a single equivalence class) and Bayesian score-based methods (Geiger and Heckerman, 1994) (which assign relative scores to the equivalence classes) are available. On the contrary, all current methods able to utilize non-Gaussianity in the data (Shimizu et al., 2006; Hoyer et al., 2008) always return only a single graph or a single equivalence class, and so are fundamentally unable to express the degree of certainty attached to that output. In this paper we develop a Bayesian score-based approach able to take advantage of non-Gaussianity when estimating linear acyclic causal models, and we empirically demonstrate that, at least on very modest size networks, its accur...

  3. Acyclic nucleoside bisphosphonates as inhibitors of 6-oxopurine phosphoribosyltransferases: Potential antimalarial and antibacterial agents

    Hocková, Dana; Keough, D. T.; Špaček, Petr; Janeba, Zlatko; Edstein, M. D.; Chavchich, M.; Wang, T. H.; Eng, W. S.; West, N. P.; de Jersey, J.; Guddat, L. W.

    Praha: Institute of Organic Chemistry and Biochemistry AS CR, v. v. i, 2014 - (Hocek, M.), s. 107-110. (Collection Symposium Series. 14). ISBN 978-80-86241-50-0. [Symposium on Chemistry of Nucleic Acid Components /16./. Český Krumlov (CZ), 08.06.2014-13.06.2014] R&D Projects: GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : nucleotide analogues * enzyme inhibitors * Plasmodium Subject RIV: CC - Organic Chemistry

  4. Enzymatic synthesis of ester prodrugs of acyclic nucleoside analogues by Candida antarctica lipase

    Lamatová, Nikola; Krečmerová, Marcela; Spiwok, V.; Brabcová, Jana

    Praha: Czech Chemical Society, 2015. s. 106. [Liblice 2015. Advances in Organic, Bioorganic and Pharmaceutical Chemistry /50./. 06.11.2015-08.11.2015, Olomouc] R&D Projects: GA ČR(CZ) GA14-00522S Institutional support: RVO:61388963 Keywords : vinil esters * lipase * enzymatic esterification Subject RIV: CC - Organic Chemistry

  5. New prodrugs of Adefovir and Cidofovir

    Tichý, Tomáš; Andrei, G.; Dračínský, Martin; Holý, Antonín; Balzarini, J.; Snoeck, R.; Krečmerová, Marcela

    2011-01-01

    Roč. 19, č. 11 (2011), s. 3527-3539. ISSN 0968-0896 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : adefovir * cidofovir * antivirals * prodrugs * acyclic nucleoside phosphonate * phosphonate ester * in vitro evaluation Subject RIV: CC - Organic Chemistry Impact factor: 2.921, year: 2011

  6. Nucleoside Inhibitors of Zika Virus.

    Eyer, Luděk; Nencka, Radim; Huvarová, Ivana; Palus, Martin; Joao Alves, Maria; Gould, Ernest A; De Clercq, Erik; Růžek, Daniel

    2016-09-01

    There is growing evidence that Zika virus (ZIKV) can cause devastating infant brain defects and other neurological disorders in humans. However, no specific antiviral therapy is available at present. We tested a series of 2'-C- or 2'-O-methyl-substituted nucleosides, 2'-C-fluoro-2'-C-methyl-substituted nucleosides, 3'-O-methyl-substituted nucleosides, 3'-deoxynucleosides, derivatives with 4'-C-azido substitution, heterobase-modified nucleosides, and neplanocins for their ability to inhibit ZIKV replication in cell culture. Antiviral activity was identified when 2'-C-methylated nucleosides were tested, suggesting that these compounds might represent promising lead candidates for further development of specific antivirals against ZIKV. PMID:27234417

  7. Synthesis of novel fluorocarbocyclic nucleosides and nucleotides as potential inhibitors of human immunodeficiency virus

    Hilpert, H.

    1989-01-01

    3[prime]-Azido-3[prime]-deoxythymidine (AZT) and 2[prime], 3[prime]-dideoxycytidine (DDC) are potent in vivo inhibitors of human immunodeficiency virus. Due to their short half-life in the body and undesired side-effects compounds with improved bioavailability were designed. A feature of these analogues was the replacement of the heterocyclic oxygen atom by an isosteric CHF-group thus stabilizing the labile glycosidic bond against metabolic breakdown. A versatile and short synthesis, starting from ketone, serves to construct the highly functionalized and protected key intermediates. These ([alpha]- and [beta]-fluoro epimeric) intermediates were elaborated to eight fluorocarbocyclic nucleoside analogues linked with a thymine base, an adenine base, and a guanine base. An attempt was made to prepare analogues of the potent HIV inhibitor carbovir c. The unexpected oxidation of the double bond of compound d, instead of the desired Baeyer-Villiger ring-expansion, meant that the synthetic scheme was redundant. A second total synthesis involves the preparation of the three fluorocarbocyclic phosphonates. These analogues possess additionally a P-C linkage which should markedly enhance the stability of the side chain. To perform enzyme inhibition tests, three analogues were chemically activated to the biologically active triphosphates. Inhibition tests on HIV associated reverse transcriptase confirmed the high activity of one of the AZT triphosphates. The fluorocarbocyclic counterpart was two orders of magnitude less active. A fluorocarbocyclic phosphonate was twice as active as the AZT triphosphate. Neither the eight nucleoside analogues nor the three phosphonates displayed significant activity against HIV infected cells. Crystallographic data of two fluorocarbocyclic nucleosides, two potent HIV inhibitors, and some 20 examples of 2[prime]-deoxyribonucleosides have been compared.

  8. Homology cylinders and the acyclic closure of a free group

    Sakasai, Takuya

    2005-01-01

    We give a Dehn-Nielsen type theorem for the homology cobordism group of homology cylinders by considering its action on the acyclic closure, which was defined by Levine, of a free group. Then we construct an additive invariant of those homology cylinders which act on the acyclic closure trivially. We also describe some tools to study the automorphism group of the acyclic closure of a free group generalizing those for the automorphism group of a free group or the homology cobordism group of ho...

  9. Approximating acyclicity parameters of sparse hypergraphs

    Fomin, Fedor V; Thilikos, Dimitrios M

    2008-01-01

    The notions of hypertree width and generalized hypertree width were introduced by Gottlob, Leone, and Scarcello in order to extend the concept of hypergraph acyclicity. These notions were further generalized by Grohe and Marx, who introduced the fractional hypertree width of a hypergraph. All these width parameters on hypergraphs are useful for extending tractability of many problems in database theory and artificial intelligence. In this paper, we study the approximability of (generalized, fractional) hyper treewidth of sparse hypergraphs where the criterion of sparsity reflects the sparsity of their incidence graphs. Our first step is to prove that the (generalized, fractional) hypertree width of a hypergraph H is constant-factor sandwiched by the treewidth of its incidence graph, when the incidence graph belongs to some apex-minor-free graph class. This determines the combinatorial borderline above which the notion of (generalized, fractional) hypertree width becomes essentially more general than treewidth...

  10. Acyclic archaebacterial ether lipids in swamp sediments

    Pauly, George G.; Van Vleet, Edward S.

    1986-06-01

    Acyclic phytanyl diether glycerol and biphytanyl ether lipids have been quantified in two modern swamp sediment cores in concentrations ranging up to 360 μg/ml porewater. Methanogenic bacteria are the only known source organisms which can inhabit the swamp sediments. Variations in relative abundance between these lipids may reflect taxonomic changes in methanogen populations or the stage of growth. Maxima in methanogen lipid concentrations coincide with local maxima of 13C of organic matter, possibly the result of a pool effect on CO 2 or acetate. Methane production estimates calculated from lipid concentrations in swamp sediments range from 0.1 to 1.3 mmol cm -2 yr -1, values which are consistent with published methane fluxes.

  11. Methyl 4-toluenesulfonyloxymethylphosphonate, a new and versatile reagent for the convenient synthesis of phosphonate-containing compounds

    Kóšiová, Ivana; Točík, Zdeněk; Buděšínský, Miloš; Šimák, Ondřej; Liboska, Radek; Rejman, Dominik; Pačes, Ondřej; Rosenberg, Ivan

    2009-01-01

    Roč. 50, č. 49 (2009), s. 6745-6747. ISSN 0040-4039 R&D Projects: GA ČR GA202/09/0193; GA ČR GA203/09/0820; GA MŠk(CZ) LC06061; GA MŠk(CZ) LC06077; GA AV ČR KAN200520801 Institutional research plan: CEZ:AV0Z40550506 Keywords : nucleoside phosphonates * phosphonylation * methyl 4-toluenesulfonyloxymethylphosphonate Subject RIV: CC - Organic Chemistry Impact factor: 2.660, year: 2009

  12. Approved Antiviral Drugs over the Past 50 Years.

    De Clercq, Erik; Li, Guangdi

    2016-07-01

    Since the first antiviral drug, idoxuridine, was approved in 1963, 90 antiviral drugs categorized into 13 functional groups have been formally approved for the treatment of the following 9 human infectious diseases: (i) HIV infections (protease inhibitors, integrase inhibitors, entry inhibitors, nucleoside reverse transcriptase inhibitors, nonnucleoside reverse transcriptase inhibitors, and acyclic nucleoside phosphonate analogues), (ii) hepatitis B virus (HBV) infections (lamivudine, interferons, nucleoside analogues, and acyclic nucleoside phosphonate analogues), (iii) hepatitis C virus (HCV) infections (ribavirin, interferons, NS3/4A protease inhibitors, NS5A inhibitors, and NS5B polymerase inhibitors), (iv) herpesvirus infections (5-substituted 2'-deoxyuridine analogues, entry inhibitors, nucleoside analogues, pyrophosphate analogues, and acyclic guanosine analogues), (v) influenza virus infections (ribavirin, matrix 2 protein inhibitors, RNA polymerase inhibitors, and neuraminidase inhibitors), (vi) human cytomegalovirus infections (acyclic guanosine analogues, acyclic nucleoside phosphonate analogues, pyrophosphate analogues, and oligonucleotides), (vii) varicella-zoster virus infections (acyclic guanosine analogues, nucleoside analogues, 5-substituted 2'-deoxyuridine analogues, and antibodies), (viii) respiratory syncytial virus infections (ribavirin and antibodies), and (ix) external anogenital warts caused by human papillomavirus infections (imiquimod, sinecatechins, and podofilox). Here, we present for the first time a comprehensive overview of antiviral drugs approved over the past 50 years, shedding light on the development of effective antiviral treatments against current and emerging infectious diseases worldwide. PMID:27281742

  13. Acyclic Preference Systems in P2P Networks

    Gai, Anh-Tuan; Mathieu, Fabien; De Montgolfier, Fabien; Reynier, Julien; Viennot, Laurent

    2007-01-01

    In this work we study preference systems natural for the Peer-to-Peer paradigm. Most of them fall in three categories: global, symmetric and complementary. All these systems share an acyclicity property. As a consequence, they admit a stable (or Pareto efficient) configuration, where no participant can collaborate with better partners than their current ones. We analyze the representation of the such preference systems and show that any acyclic system can be represented with a symmetric mark matrix. This gives a method to merge acyclic preference systems and retain the acyclicity. We also consider such properties of the corresponding collaboration graph, as clustering coefficient and diameter. In particular, studying the example of preferences based on real latency measurements, we observe that its stable configuration is a small-world graph.

  14. Phosphonate Based High Nuclearity Magnetic Cages.

    Sheikh, Javeed Ahmad; Jena, Himanshu Sekhar; Clearfield, Abraham; Konar, Sanjit

    2016-06-21

    Transition metal based high nuclearity molecular magnetic cages are a very important class of compounds owing to their potential applications in fabricating new generation molecular magnets such as single molecular magnets, magnetic refrigerants, etc. Most of the reported polynuclear cages contain carboxylates or alkoxides as ligands. However, the binding ability of phosphonates with transition metal ions is stronger than the carboxylates or alkoxides. The presence of three oxygen donor sites enables phosphonates to bridge up to nine metal centers simultaneously. But very few phosphonate based transition metal cages were reported in the literature until recently, mainly because of synthetic difficulties, propensity to result in layered compounds, and also their poor crystalline properties. Accordingly, various synthetic strategies have been followed by several groups in order to overcome such synthetic difficulties. These strategies mainly include use of small preformed metal precursors, proper choice of coligands along with the phosphonate ligands, and use of sterically hindered bulky phosphonate ligands. Currently, the phosphonate system offers a library of high nuclearity transition metal and mixed metal (3d-4f) cages with aesthetically pleasing structures and interesting magnetic properties. This Account is in the form of a research landscape on our efforts to synthesize and characterize new types of phosphonate based high nuclearity paramagnetic transition metal cages. We quite often experienced synthetic difficulties with such versatile systems in assembling high nuclearity metal cages. Few methods have been emphasized for the self-assembly of phosphonate systems with suitable transition metal ions in achieving high nuclearity. We highlighted our journey from 2005 until today for phosphonate based high nuclearity transition metal cages with V(IV/V), Mn(II/III), Fe(III), Co(II), Ni(II), and Cu(II) metal ions and their magnetic properties. We observed that

  15. On the Existence of Undominated Elements of Acyclic Relations

    Hannu Salonen; Hannu Vartiainen

    2005-01-01

    We study the existence of undominated elements of acyclic and irreflexive relations. A sufficient condition for the existence is given in the general case without any topological assumptions. Sufficient conditions are also given when the relation in question is defined on a compact Hausdorff space. We study the existence of fixed points of acyclic correspondences, the existence of stable sets, and the possibility of representing the relation by a real valued function.

  16. Physiology and methodology of intermittent resistance training for acyclic sports

    Casas, Adrián

    2008-01-01

    Resistance training for acyclic sports has traditionally been carried out using training methods developed for cyclic sports. These methods were developed from the study of the physiological bases of maximum oxygen consumption (VO2max), prioritising “central” cardiovascular factors (cardiac) above “peripheral” factors (muscular) and omitting in-depth analysis of muscular behaviour during acyclic resistance. This article intends to: a) analyse certain physiological aspects needed to understand...

  17. Carboranyl Nucleosides & Oligonucleotides for Neutron Capture Therapy Final Report

    Schinazi, Raymond F.

    2004-12-01

    This proposal enabled us to synthesize and develop boron-rich nucleosides and oligonucleotide analogues for boron neutron capture therapy (BNCT) and the treatment of various malignancies. First, we determined the relationship between structure, cellular accumulation and tissue distribution of 5-o-carboranyl-2'-deoxyuridine (D-CDU) and its derivatives D-ribo-CU and 5-o-carboranyluracil (CU), to potentially target brain and other solid tumors for neutron capture therapy. Synthesized carborane containing nucleoside derivatives of CDU, D- and L-enantiomers of CDU, D-ribo-CU and CU were used. We measured tissue disposition in xenografted mice bearing 9479 human prostate tumors xenografts and in rats bearing 9L gliosarcoma isografts in their flanks and intracranially. The accumulation of D-CDU, 1-({beta}-L-arabinosyl)-5-o-carboranyluracil, D-ribo-CU, and CU were also studied in LnCap human prostate tumor cells and their retention was measured in male nude mice bearing LnCap and 9479 human prostate tumor xenografts. D-CDU, D-ribo-CU and CU levels were measured after administration in mice bearing 9479 human prostate tumors in their flanks. D-CDU achieved high cellular concentrations in LnCap cells and up to 2.5% of the total cellular compound was recovered in the 5'-monophosphorylated form. D-CDU cellular concentrations were similar in LnCap and 9479 tumor xenografts. Studies in tumor bearing animals indicated that increasing the number of hydroxyl moieties in the sugar constituent of the carboranyl nucleosides lead to increased rate and extent of renal elimination, a decrease in serum half-lives and an increased tissue specificity. Tumor/brain ratios were greatest for CDU and D-ribo-CU, while tumor/prostate ratios were greatest with CU. CDU and D-ribo-CU have potential for BNCT of brain malignancies, while CU may be further developed for prostate cancer. A method was developed for the solid phase synthesis of oligonucleotides containing (ocarboran-1-yl-methyl)phosphonate

  18. [Purine nucleoside phosphorylase].

    Pogosian, L G; Akopian, Zh I

    2013-01-01

    Purine nucleoside phosphorylase (PNP) is one of the most important enzymes of the purine metabolism, wich promotes the recycling of purine bases. Nowadays is the actual to search for effective inhibitors of this enzyme which is necessary for creation T-cell immunodeficient status of the organism in the organs and tissues transplantation, and chemotherapy of a number pathologies as well. For their successful practical application necessary to conduct in-depth and comprehensive study of the enzyme, namely a structure, functions, and an affinity of the reaction mechanism. In the review the contemporary achievements in the study of PNP from various biological objects are presented. New data describing the structure of PNP are summarised and analysed. The physiological role of the enzyme is discussed. The enzyme basic reaction mechanisms and actions are considered. The studies on enzyme physicochemical, kinetic, and catalytic research are presented. PMID:24479338

  19. Actinide phosphonate complexes in aqueous solutions

    Complexes formed by actinides with carboxylic acids, polycarboxylic acids, and aminopolycarboxylic acids play a central role in both the basic and process chemistry of the actinides. Recent studies of f-element complexes with phosphonic acid ligands indicate that new ligands incorporating doubly ionizable phosphonate groups (-PO3H2) have many properties which are unique chemically, and promise more efficient separation processes for waste cleanup and environmental restoration. Simple diphosphonate ligands form much stronger complexes than isostructural carboxylates, often exhibiting higher solubility as well. In this manuscript recent studies of the thermodynamics and kinetics of f-element complexation by 1,1 and 1,2 diphosphonic acid ligands are described

  20. Acyclic edge colorings of planar graphs and series parallel graphs

    HOU JianFeng; WU JianLiang; LIU GuiZhen; LIU Bin

    2009-01-01

    A proper edge coloring of a graph G is called acyclic if there is no 2-colored cycle in G.The acyclic edge chromatic number of G,denoted by a'(G),is the least number of colors in an acyclic edge coloring of G.Alon et al.conjectured that a'(G) ≤△(G) +2 for any graphs.For planar graphs G with girth g(G),we prove that a'(G) ≤ max{2△(G)-2,△(G) +22} if g(G) ≥3,a'(G)≤△(G)+2if g(G) ≥ 5,a'(G) ≤△(G)+1 if g(G) ≥ 7,and a'(G)=△(G) if g(G) ≥ 16 and △(G) ≥ 3.For series-parallel graphs G,we have a'(G) ≤ △(G) +1.

  1. Removal and Recovery of Phosphonate Antiscalants

    Boels, L.

    2012-01-01

    In reverse osmosis (RO) desalination processes, the use of phosphonates prevents scaling, thus allowing for a higher product water recovery, which increases the efficiency of the process. However, a major concern associated with their use in RO desalination is the high cost and environmental impacts

  2. Inverse Eigenvalue Problems for Two Special Acyclic Matrices

    Debashish Sharma

    2016-03-01

    Full Text Available In this paper, we study two inverse eigenvalue problems (IEPs of constructing two special acyclic matrices. The first problem involves the reconstruction of matrices whose graph is a path, from given information on one eigenvector of the required matrix and one eigenvalue of each of its leading principal submatrices. The second problem involves reconstruction of matrices whose graph is a broom, the eigen data being the maximum and minimum eigenvalues of each of the leading principal submatrices of the required matrix. In order to solve the problems, we use the recurrence relations among leading principal minors and the property of simplicity of the extremal eigenvalues of acyclic matrices.

  3. Synthesis and Early Development of Hexadecyloxypropyl-cidofovir: An Oral Antipoxvirus Nucleoside Phosphonate

    Karl Y. Hostetler

    2010-09-01

    Full Text Available Hexadecyloxypropyl-cidofovir (HDP-CDV is a novel ether lipid conjugate of (S-1-(3-hydroxy-2-phosphonoylmethoxypropyl-cytosine (CDV which exhibits a remarkable increase in antiviral activity against orthopoxviruses compared with CDV. In contrast to CDV, HDP-CDV is orally active and lacks the nephrotoxicity of CDV itself. Increased oral bioavailability and increased cellular uptake is facilitated by the lipid portion of the molecule which is responsible for the improved activity profile. The lipid portion of HDP-CDV is cleaved in the cell, releasing CDV which is converted to CDV diphosphate, the active metabolite. HDP-CDV is a highly effective agent against a variety of orthopoxvirus infections in animal models of disease including vaccinia, cowpox, rabbitpox and ectromelia. Its activity was recently demonstrated in a case of human disseminated vaccinia infection after it was added to a multiple drug regimen. In addition to the activity against orthopoxviruses, HDP-CDV (CMX001 is active against all double stranded DNA viruses including CMV, HSV-1, HSV-2, EBV, adenovirus, BK virus, orf, JC, and papilloma viruses, and is under clinical evaluation as a treatment for human infections with these agents.

  4. Evaluation of nucleoside phosphonates and their analogs and prodrugs for inhibition of orthopoxvirus replication

    Keith, K. A.; Hitchcock, M. J. M.; Lee, W. A.; Holý, Antonín; Kern, E. R.

    2003-01-01

    Roč. 47, č. 7 (2003), s. 2193-2198. ISSN 0066-4804 R&D Projects: GA AV ČR IBS4055109 Grant ostatní: Public Health Service(US) NO1-AI-85347 Institutional research plan: CEZ:AV0Z4055905 Keywords : adefovir * cidofovir * tenofovir Subject RIV: CC - Organic Chemistry Impact factor: 4.246, year: 2003

  5. New acyclic diterpenic acids from yacon (Smallanthus sonchifolius) leaves.

    Mercado, María I; Coll Aráoz, María V; Grau, Alfredo; Catalán, César A N

    2010-11-01

    Two new acyclic diterpenoids, smaditerpenic acid E (1a) and F (2a), along with nineteen melampolide-type sesquiterpene lactones, six of them not previously reported in yacon, were isolated from the methylene chloride leaf rinse extract. Their structures were elucidated from 1D and 2D NMR experiments and gas chromatography coupled to mass spectrometry. PMID:21213966

  6. Diversity and abundance of phosphonate biosynthetic genes in nature

    Yu, Xiaomin; Doroghazi, James R.; Janga, Sarath C.; Zhang, Jun Kai; Circello, Benjamin; Griffin, Benjamin M.; Labeda, David P.; Metcalf, William W.

    2013-01-01

    Phosphonic acids are organophosphorus molecules containing direct carbon–phosphorus bonds that are often perceived as biological rarities. The data presented here show that the ability to synthesize diverse phosphonates is both widespread and relatively common among microbes. These findings are consistent with recent evidence suggesting that phosphonates are important intermediates in the global phosphorus cycle. Moreover, they support the idea that these molecules play a significant role in ...

  7. Novel isopolar non-isosteric phosphonate analogues of 3´-deoxy-3´,4´-didehydronucleoside 5´-phosphates

    Petrová, Magdalena; Buděšínský, Miloš; Rosenberg, Ivan

    Lyon : Université de Lyon, 2010, s. 311-312. [International Roundtable on Nucleosides, Nucleotides and Nucleic Acids. IRT 2010. Lyon (FR), 29.08.2010-03.09.2010] R&D Projects: GA MŠk(CZ) LC06077; GA MŠk(CZ) LC06061; GA ČR GA202/09/0193 Institutional research plan: CEZ:AV0Z40550506 Keywords : phosphonate analog * triphosphate analog * didehydronucleoside Subject RIV: CC - Organic Chemistry http://irt2010.univ-lyon1.fr

  8. Studies on the sodium borohydride reduction of unsaturated keto nucleosides. Novel route to deoxy nucleosides

    Reduction of α,β-unsaturated (ketohexosyl)purines, which constitute the first examples of unsaturated keto nucleosides, with sodium borohydride gave the corresponding deoxy nucleosides. Contrary to the recently reported (4',6'-dideoxy-β-L-glycero-hex3'-enopyranosulosyl)purines, which were obtained by acetylation of the corresponding keto nucleosides, the α anomer, subsequently described, was prepared by oxidation of the partially protected deoxyhexosylpurine. The mechanisms of these reductions were established by a study of the NMR spectra of the deoxy nucleosides using NaBH4 in deuterated solvents and sodium borodeuteride in light solvents. 1,2 addition of the hydride was shown to be the mode of reduction of all the studied α- and β-unsaturated keto nucleosides. The ready availability of these unsaturated keto nucleosides provides extremely useful synthetic intermediate nucleosides especially for the preparation of nucleosides containing rare deoxy sugars

  9. Epoxy Phosphonate Crosslinkers for Providing Flame Resistance to Cotton Textiles

    Two new monomers (2-methyl-oxiranylmethyl)-phosphonic acid dimethyl ester (3) and [2-(dimethoxy-phosphorylmethyl)-oxyranylmethyl]-phosphonic acid dimethyl ester (6) were prepared and used with dicyandiamide (7) and citric acid (8) to impart flame resistance to cotton plain weave, twill, and 80:20-co...

  10. Base-Modified Nucleosides: Etheno Derivatives

    Jahnz-Wechmann, Zofia; Framski, Grzegorz R.; Januszczyk, Piotr A.; Boryski, Jerzy

    2016-01-01

    This review presents synthesis and chemistry of nucleoside analogs, possessing an additional fused, heterocyclic ring of the “etheno” type, such as 1,N6-ethenoadenosine, 1,N4-ethenocytidine, 1,N2-ethenoguanosine, and other related derivatives. Formation of ethenonucleosides, in the presence of α-halocarbonyl reagents and their mechanism, stability, and degradation, reactions of substitution and transglycosylation, as well as their application in the nucleoside synthesis, have been described. Some of the discussed compounds may be applied as chemotherapeutic agents in antiviral and anticancer treatment, acting as pro-nucleosides of already known, biologically active nucleoside analogs. PMID:27200341

  11. Marine Nucleosides: Structure, Bioactivity, Synthesis and Biosynthesis

    Ri-Ming Huang

    2014-12-01

    Full Text Available Nucleosides are glycosylamines that structurally form part of nucleotide molecules, the building block of DNA and RNA. Both nucleosides and nucleotides are vital components of all living cells and involved in several key biological processes. Some of these nucleosides have been obtained from a variety of marine resources. Because of the biological importance of these compounds, this review covers 68 marine originated nucleosides and their synthetic analogs published up to June 2014. The review will focus on the structures, bioactivities, synthesis and biosynthetic processes of these compounds.

  12. Directed acyclic graphs with edge-specific bounds

    VanderWeele, Tyler J; Tan, Zhiqiang

    2011-01-01

    We give a definition of a bounded edge within the causal directed acyclic graph framework. A bounded edge generalizes the notion of a signed edge and is defined in terms of bounds on a ratio of survivor probabilities. We derive rules concerning the propagation of bounds. Bounds on causal effects in the presence of unmeasured confounding are also derived using bounds related to specific edges on a graph. We illustrate the theory developed by an example concerning estimating the effect of antih...

  13. LAYERWIDTH: Analysis of a New Metric for Directed Acyclic Graphs

    Hopkins, Mark

    2012-01-01

    We analyze a new property of directed acyclic graphs (DAGs), called layerwidth, arising from a class of DAGs proposed by Eiter and Lukasiewicz. This class of DAGs permits certain problems of structural model-based causality and explanation to be tractably solved. In this paper, we first address an open question raised by Eiter and Lukasiewicz - the computational complexity of deciding whether a given graph has a bounded layerwidth. After proving that this problem is NP-complete, we proceed by...

  14. Understanding Model Counting for beta-acyclic CNF-formulas

    Brault-Baron, Johann; Capelli, Florent; Mengel, Stefan

    2015-01-01

    We show that SAT on beta-acyclic CNF-formulas can be solved in polynomial time. In contrast to previous algorithms for other structurally restricted classes of formulas, our algorithm does not proceed by dynamic programming. Instead, it works along an elimination order, solving a weighted version of constraint satisfaction. We give evidence that this deviation from more standard algorithms is no coincidence by showing that it is outside of the framework recently proposed by Saether et al. (SA...

  15. Acyclic Preference Systems in P2P Networks

    Gai, Anh-Tuan; Lebedev, Dmitry; Mathieu, Fabien; de Montgolfier, Fabien; Reynier, Julien; Viennot, Laurent

    2007-01-01

    The original publication is available at www.springerlink.com International audience In this work we study preference systems suitable for the Peer-to-Peer paradigm. Most of them fall in one of the three following categories: global, symmetric and complementary. All these systems share an acyclicity property. As a consequence, they admit a stable (or Pareto efficient) configuration, where no participant can collaborate with better partners than their current ones. We analyze the represe...

  16. Extending Acyclicity Notions for Existential Rules (\\emph{long version})

    Baget, Jean-Francois; Garreau, Fabien; Mugnier, Marie-Laure; Rocher, Swan

    2014-01-01

    Existential rules have been proposed for representing ontological knowledge, specifically in the context of Ontology-Based Query Answering. Entailment with existential rules is undecidable. We focus in this paper on conditions that ensure the termination of a breadth-first forward chaining algorithm known as the chase. First, we propose a new tool that allows to extend existing acyclicity conditions ensuring chase termination, while keeping good complexity properties. Second, we consider the ...

  17. Path-equivalent developments in acyclic weighted automata

    Giraud, Mathieu; Veber, Philippe; Lavenier, Dominique

    2007-01-01

    Weighted finite automata (WFA) are used with FPGA accelerating hardware to scan large genomic banks. Hardwiring such automata raises surface area and clock frequency constraints, requiring efficient ε-transitions-removal techniques. In this paper, we present bounds on the number of new transitions for the development of acyclic WFA, which is a special case of the ε-transitions-removal problem. We introduce a new problem, a partial removal of ε-transitions while accepting short chains of ε-transi...

  18. Modelling discrete longitudinal data using acyclic probabilistic finite automata

    Anantharama Ankinakatte, Smitha; Edwards, David

    2015-01-01

    Acyclic probabilistic finite automata (APFA) constitute a rich family of models for discrete longitudinal data. An APFA may be represented as a directed multigraph, and embodies a set of context-specific conditional independence relations that may be read off the graph. A model selection algorith...... assessed using cross-validation. The comparisons are based on three data sets, two from molecular genetics and one from social science. The proposed algorithm performs at least as well as the algorithm in Beagle in both respects...

  19. Studying the structure of complex networks by the transition to acyclic networks

    Shevchuk, R

    2010-01-01

    The directed acyclic networks is the fundamental class of networks which include network citation, food chains, family trees and other networks with similar structure. In this paper we present an algorithm for transforming an ordinary undirected complex network into acyclic one and further analysis of the structure of a complex network.

  20. A Distributed Algorithm for Determining Minimal Covers of Acyclic Database Schemes

    叶新铭

    1994-01-01

    Acyclic databases possess several desirable properties for their design and use.A distributed algorithm is proposed for determining a minimal cover of an alpha-,beta-,gamma-,or Berge-acyclic database scheme over a set of attributes in a distributed environment.

  1. Safety assessment in pigs of an experimental molecule with in-vitro antiviral activity against African swine fever

    Roels, S.; Van der Heyden, S.; Neyts, J.; Krečmerová, Marcela; Koenen, F.; Cay, A. B.; Tignon, M.

    Elsevier. Roč. 148, č. 1 (2013), s. 94-94. ISSN 0021-9975. [Meeting of the European Society of Veterinary Pathology /30./. 05.08.2013-08.08.2013, León] Institutional support: RVO:61388963 Keywords : African swine fever * HPMPDAP * acyclic nucleoside phosphonate * toxicity Subject RIV: CC - Organic Chemistry

  2. Role of Caspases and CD95/Fas in the Apoptotic Effects of a Nucleotide Analog PMEG in CCRF-CEM Cells

    Mertlíková-Kaiserová, Helena; Votruba, Ivan; Matoušová, Marika; Holý, Antonín; Hájek, Miroslav

    2010-01-01

    Roč. 30, č. 7 (2010), s. 2791-2798. ISSN 0250-7005 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonate * programmed cell death * CCRF-CEM cells * cell cycle Subject RIV: CC - Organic Chemistry Impact factor: 1.656, year: 2010

  3. 6-Oxopurine Phosphoribosyltransferase: A Target for the Development of Antimalarial Drugs

    de Jersey, J.; Holý, Antonín; Hocková, Dana; Naesens, L.; Keough, D. T.; Guddat, L. W.

    2011-01-01

    Roč. 11, č. 16 (2011), s. 2085-2102. ISSN 1568-0266 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : Malaria * acyclic nucleoside phosphonates * hypoxanthine * guanine phosphoribosyl transferase Subject RIV: CC - Organic Chemistry Impact factor: 4.174, year: 2011

  4. Synthesis of 9-phosphonoalkyl and 9-phosphonoalkoxyalkyl purines: Evaluation of their ability to act as inhibitors of Plasmodium falciparum, Plasmodium vivax and human hypoxanthine-guanine-(xanthine) phosphoribosyltransferases

    Česnek, Michal; Hocková, Dana; Holý, Antonín; Dračínský, Martin; Baszczyňski, Ondřej; de Jersey, J.; Keough, D. T.; Guddat, L. W.

    2012-01-01

    Roč. 20, č. 2 (2012), s. 1076-1089. ISSN 0968-0896 R&D Projects: GA MŠk 1M0508; GA ČR GAP207/11/0108 Institutional research plan: CEZ:AV0Z40550506 Keywords : Plasmodium * malaria * acyclic nucleoside phosphonates Subject RIV: CC - Organic Chemistry Impact factor: 2.903, year: 2012

  5. Transdermal Delivery and Cutaneous Targeting of Antivirals using a Penetration Enhancer and Lysolipid Prodrugs

    Diblíková, D.; Kopečná, M.; Školová, B.; Krečmerová, Marcela; Roh, J.; Hrabálek, A.; Vávrová, K.

    2014-01-01

    Roč. 31, č. 4 (2014), s. 1071-1081. ISSN 0724-8741 Grant ostatní: GA ČR(CZ) GAP207/11/0365 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonate antivirals * lysolipid prodrug * penetration enhancer * skin absorption * transdermal drug delivery Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 3.420, year: 2014

  6. 9-[2-(R)-(Phosphonomethoxy)propyl]-2,6-diaminopurine (R)-PMPDAP and its prodrugs: Optimized preparation, including identification of by-products formed, and antiviral evaluation in vitro

    Krečmerová, Marcela; Jansa, Petr; Dračínský, Martin; Sázelová, Petra; Kašička, Václav; Neyts, J.; Auwerx, J.; Kiss, E.; Goris, N.; Stepan, G.; Janeba, Zlatko

    2013-01-01

    Roč. 21, č. 5 (2013), s. 1199-1208. ISSN 0968-0896 R&D Projects: GA MŠk(CZ) ME10040 Institutional support: RVO:61388963 Keywords : PMPDAP * Acyclic nucleoside phosphonates * (Phosphonomethoxy)propyl * purine * antivirals * HIV Subject RIV: CC - Organic Chemistry Impact factor: 2.951, year: 2013

  7. Efficient synthesis and anti-HIV activity of N6-substituted FPMP derivatives of adenine and 2,6-diaminopurine

    Baszczyňski, Ondřej; Holý, Antonín; Jansa, Petr; Janeba, Zlatko; Dračínský, Martin; Klepetářová, Blanka

    Amsterdam: Elsevier, 2010. P1.04-P1.04. [Antivirals Congress. Celebrating 30 years of the journal Antiviral Research. 07.11.2010-09.11.2010, Amsterdam] R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : HIV * ANPs * acyclic nucleoside phosphonates * FPMP Subject RIV: CC - Organic Chemistry

  8. Synthesis and antimalarial activity of purine 9-[2-hydroxy-3-(phosphonomethoxy)propyl] derivatives and their side-chain modified analogues

    Krečmerová, Marcela; Holý, Antonín; Hocková, Dana; Dračínský, Martin; de Jersey, J.; Keough, D. T.; Guddat, L. W.

    Pasadena : ACS, 2011. RM WRM17-RM WRM17. [Western Regional Meeting /43./. 10.11.2011-12.11.2011, Pasadena] R&D Projects: GA MŠk 1M0508; GA ČR GAP207/11/0108 Institutional research plan: CEZ:AV0Z40550506 Keywords : HGXPRT * plasmodium * acyclic nucleoside phosphonates Subject RIV: CC - Organic Chemistry

  9. Mutations Conferring Resistance to Viral DNA Polymerase Inhibitors in Camelpox Virus Give Different Drug-Susceptibility Profiles in Vaccinia Virus

    Duraffour, S.; Andrei, G.; Topalis, D.; Krečmerová, Marcela; Crance, J. M.; Garin, D.; Snoeck, R.

    2012-01-01

    Roč. 86, č. 13 (2012), s. 7310-7325. ISSN 0022-538X Institutional support: RVO:61388963 Keywords : camelpox virus * CMLV * vaccinia virus VACV * acyclic nucleoside phosphonates * HPMPDAP * cidofovir * drug resistance Subject RIV: CC - Organic Chemistry Impact factor: 5.076, year: 2012

  10. N-4-Acyl derivatives as lipophilic prodrugs of cidofovir and its 5-azacytosine analogue, (S)-HPMP-5-azaC: Chemistry and antiviral activity

    Krečmerová, Marcela; Pohl, Radek; Masojídková, Milena; Balzarini, J.; Snoeck, R.; Andrei, G.

    2014-01-01

    Roč. 22, č. 10 (2014), s. 2896-2906. ISSN 0968-0896 R&D Projects: GA MPO FR-TI4/625 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonate * antivirals * 5-azacytosine * prodrug Subject RIV: CC - Organic Chemistry Impact factor: 2.793, year: 2014

  11. Synthesis and biological properties of prodrugs of (S)-3-(adenin-9-yl)-2-(phosphonomethoxy)propanoic acid

    Kaiser, Martin Maxmilian; Poštová Slavětínská, Lenka; Dračínský, Martin; Lee, Y. J.; Tian, Y.; Janeba, Zlatko

    2016-01-01

    Roč. 108, Jan 27 (2016), s. 374-380. ISSN 0223-5234 R&D Projects: GA MV VG20102015046 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * (S)-CPMEA * antiviral * HCV * prodrugs Subject RIV: CC - Organic Chemistry Impact factor: 3.447, year: 2014

  12. Immunobiological activity of N-[2-(phosphonomethoxy)-alkyl] derivatives of N6-substituted adenines, and 2,6-diaminopurines

    Zídek, Zdeněk; Potměšil, Petr; Kmoníčková, Eva; Holý, Antonín

    2003-01-01

    Roč. 475, - (2003), s. 149-159. ISSN 0014-2999 R&D Projects: GA ČR GA305/00/0048 Institutional research plan: CEZ:AV0Z5039906; CEZ:AV0Z4055905 Keywords : acyclic nucleoside phosphonates Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 2.352, year: 2003

  13. Role acyklických nukleosidfosfonátů jako potenciálních antimalarik

    Janeba, Zlatko; Hocková, Dana

    2014-01-01

    Roč. 108, č. 4 (2014), s. 335-343. ISSN 0009-2770 R&D Projects: GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : acyclic nucleoside phosphonates * prodrugs * antivirals * antimalarials Subject RIV: CC - Organic Chemistry Impact factor: 0.272, year: 2014

  14. Extent of Intramolecular p-Stacks in Aqueous Solution in Mixed-Ligand Copper(II) Complexes Formed by Heteroaromatic Amines and Several 2-Aminopurine Derivatives of the Antivirally Active Nucleotide Analog 9-[2-(Phosphonomethoxy)ethyl]adenine (PMEA)

    Gómez-Coca, R. B.; Blindauer, C. A.; Sigel, A.; Operschall, B. P.; Holý, Antonín; Sigel, H.

    2012-01-01

    Roč. 9, č. 9 (2012), s. 2008-2034. ISSN 1612-1872 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : copper complexes * nucleotides * acyclic nucleoside phosphonates * ANPs * antiviral activity Subject RIV: CE - Biochemistry Impact factor: 1.808, year: 2012

  15. Synthesis of tyrosine side chain-linked prodrugs of PMEG and cpr-PMEDAP

    Tichý, Tomáš; Pomeisl, Karel; Krečmerová, Marcela; McKenna, C.

    Pasadena : ACS, 2011. RM WRM16-RM WRM16. [Western Regional Meeting /43./. 10.11.2011-12.11.2011, Pasadena] R&D Projects: GA MŠk 1M0508; GA MŠk(CZ) ME10040 Institutional research plan: CEZ:AV0Z40550506 Keywords : prodrugs * tyrosine * acyclic nucleoside phosphonate * antiproliferative effects Subject RIV: CC - Organic Chemistry

  16. Permeation enhancer dedocyl 6-(dimethylamino)hexanoate increases transdermal and topical delivery of adefovir: Influence of pH, ion-pairing and skin species

    Vávrová, K.; Lorencová, K.; Novotný, J.; Holý, Antonín; Hrabálek, A.

    2008-01-01

    Roč. 70, č. 3 (2008), s. 901-907. ISSN 0939-6411 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : adefovir * acyclic nucleoside phosphonates * antiviral * transdermal drug delivery * permeation enhancer Subject RIV: CC - Organic Chemistry Impact factor: 3.344, year: 2008

  17. Worst-case Behaviour of History Based Pivot Rules on Acyclic Unique Sink Orientations of Hypercubes

    Aoshima, Yoshikazu; Deering, Theresa; Matsumoto, Yoshitake; Moriyama, Sonoko

    2011-01-01

    An acyclic USO on a hypercube is formed by directing its edges in such as way that the digraph is acyclic and each face of the hypercube has a unique sink and a unique source. A path to the global sink of an acyclic USO can be modeled as pivoting in a unit hypercube of the same dimension with an abstract objective function, and vice versa. In such a way, Zadeh's 'least entered rule' and other history based pivot rules can be applied to the problem of finding the global sink of an acyclic USO. In this paper we present some theoretical and empirical results on the worst case behaviour of various history based pivot rules for this problem. In particular, we investigate whether or not they can follow a Hamiltonian path on an acyclic USO.

  18. Block and Graft Copolymers Containing Carboxylate or Phosphonate Anions

    Hu, Nan

    2014-01-01

    This dissertation focuses on synthesis and characterization of graft and block copolymers containing carboxylate or phosphonate anions that are potential candidates for biomedical applications such as drug delivery and dental adhesives. Ammonium bisdiethylphosphonate (meth)acrylate and acrylamide phosphonate monomers were synthesized based on aza-Michael addition reactions. Free radical copolymerizations of these monomers with an acrylate-functional poly(ethylene oxide) (PEO) macromonomer...

  19. Towards Optimal Event Detection and Localization in Acyclic Flow Networks

    Agumbe Suresh, Mahima

    2012-01-03

    Acyclic flow networks, present in many infrastructures of national importance (e.g., oil & gas and water distribution systems), have been attracting immense research interest. Existing solutions for detecting and locating attacks against these infrastructures, have been proven costly and imprecise, especially when dealing with large scale distribution systems. In this paper, to the best of our knowledge for the first time, we investigate how mobile sensor networks can be used for optimal event detection and localization in acyclic flow networks. Sensor nodes move along the edges of the network and detect events (i.e., attacks) and proximity to beacon nodes with known placement in the network. We formulate the problem of minimizing the cost of monitoring infrastructure (i.e., minimizing the number of sensor and beacon nodes deployed), while ensuring a degree of sensing coverage in a zone of interest and a required accuracy in locating events. We propose algorithms for solving these problems and demonstrate their effectiveness with results obtained from a high fidelity simulator.

  20. On Event Detection and Localization in Acyclic Flow Networks

    Suresh, Mahima Agumbe

    2013-05-01

    Acyclic flow networks, present in many infrastructures of national importance (e.g., oil and gas and water distribution systems), have been attracting immense research interest. Existing solutions for detecting and locating attacks against these infrastructures have been proven costly and imprecise, particularly when dealing with large-scale distribution systems. In this article, to the best of our knowledge, for the first time, we investigate how mobile sensor networks can be used for optimal event detection and localization in acyclic flow networks. We propose the idea of using sensors that move along the edges of the network and detect events (i.e., attacks). To localize the events, sensors detect proximity to beacons, which are devices with known placement in the network. We formulate the problem of minimizing the cost of monitoring infrastructure (i.e., minimizing the number of sensors and beacons deployed) in a predetermined zone of interest, while ensuring a degree of coverage by sensors and a required accuracy in locating events using beacons. We propose algorithms for solving the aforementioned problem and demonstrate their effectiveness with results obtained from a realistic flow network simulator.

  1. Insights into phosphate cooperativity and influence of substrate modifications on binding and catalysis of hexameric purine nucleoside phosphorylases.

    Priscila O de Giuseppe

    Full Text Available The hexameric purine nucleoside phosphorylase from Bacillus subtilis (BsPNP233 displays great potential to produce nucleoside analogues in industry and can be exploited in the development of new anti-tumor gene therapies. In order to provide structural basis for enzyme and substrates rational optimization, aiming at those applications, the present work shows a thorough and detailed structural description of the binding mode of substrates and nucleoside analogues to the active site of the hexameric BsPNP233. Here we report the crystal structure of BsPNP233 in the apo form and in complex with 11 ligands, including clinically relevant compounds. The crystal structure of six ligands (adenine, 2'deoxyguanosine, aciclovir, ganciclovir, 8-bromoguanosine, 6-chloroguanosine in complex with a hexameric PNP are presented for the first time. Our data showed that free bases adopt alternative conformations in the BsPNP233 active site and indicated that binding of the co-substrate (2'deoxyribose 1-phosphate might contribute for stabilizing the bases in a favorable orientation for catalysis. The BsPNP233-adenosine complex revealed that a hydrogen bond between the 5' hydroxyl group of adenosine and Arg(43* side chain contributes for the ribosyl radical to adopt an unusual C3'-endo conformation. The structures with 6-chloroguanosine and 8-bromoguanosine pointed out that the Cl(6 and Br(8 substrate modifications seem to be detrimental for catalysis and can be explored in the design of inhibitors for hexameric PNPs from pathogens. Our data also corroborated the competitive inhibition mechanism of hexameric PNPs by tubercidin and suggested that the acyclic nucleoside ganciclovir is a better inhibitor for hexameric PNPs than aciclovir. Furthermore, comparative structural analyses indicated that the replacement of Ser(90 by a threonine in the B. cereus hexameric adenosine phosphorylase (Thr(91 is responsible for the lack of negative cooperativity of phosphate binding

  2. The Existence Condition of γ-Acyclic Database Schemes with MVDs Constraints

    郝忠孝; 姚春龙

    2002-01-01

    It is very important to use database technology for a large-scale system such as ERP and MIS. A good database design may improve the performance of the system. Some researches show that a γ-acyclic database scheme has many good properties, e.g., each connected join expression is monotonous, which helps to improve query performance of the database system. Thus what conditions are needed to generate a γ-acyclic database scheme for a given relational scheme? In this paper, the sufficient and necessary condition of the existence of γ-acyclic, join-lossless and dependencies-preserved database schemes meeting 4NF is given.

  3. Isolation of a Stable, Acyclic, Two-Coordinate Silylene

    Rekken, Brian; Brown, Thomas; Fettinger, James; Tuononen, Heikki; Power, Philip

    2012-01-01

    The synthesis and characterization of a stable, acyclic two-coordinate silylene, Si(SArMe6)2, (ArMe6 = C6H3-2,6(C6H2-2,4,6-Me3)2) by reduction of Br2Si(SArMe6)2 with a magnesium(I) reductant is described. It features a v-shaped silicon coordination with a S-Si-S angle of 90.519(2)° and an average Si-S distance of 2.158(3) Å. Although it reacts readily with an alkyl halide, it does not react with hydrogen under ambient conditions probably as a result of the ca. 4.3 e...

  4. A sufficient condition for acyclic social choice in a single-profile world

    Lahiri, Somdeb

    2009-01-01

    In this paper we provide a sufficient condition for a social welfare relation to be a social decision relation (i.e. an acyclic social welfare relation) when the profile of individual preferences is given.

  5. Prebiotic phosphorylation of nucleosides in formamide

    Schoffstall, A. M.

    1976-01-01

    Results are presented for an experimental study intended to assess phosphorylation under neither aqueous nor dry thermal conditions. Instead, phosphorylations were attempted in possible nonaqueous prebiotic solvents. Formamide appeared to be the most obvious candidate for phosphorylation studies. Three main classes of phosphorylated products were formed in formamide solution: adenosine monophosphates, cyclic adenosine phosphate, and adenosine diphosphates. Experiments were designed to investigate the extent of phosphorylation of nucleosides in formamide, the relative amounts of nucleoside monophosphate, diphosphates and cyclic phosphate formed and the relative effectiveness of different sources of phosphate as phosphorylating agents in formamide. Reaction variables were temperature, nature of the phosphate or condensed phosphate, nucleoside, concentration of reactants and possible effects of additives. Product identification was based on qualitative and quantitative thin layer chromatography.

  6. Titanium-zirconium-phosphonate hybrid film on 6061 aluminum alloy

    Shuanghong WANG; Lei WANG; Changsheng LIU

    2011-01-01

    Three titanium-zirconium-phosphonate hybrid films were formed on AA6061 aluminum alloy by immersing in fluorotitanic acid and fluorozirconic acid based solution containing different phosphonic acids for protective coatings of aluminium alloy. The corrosion resistance of three hybrid films as the substitute for chromate film were evaluated and compared. The neutral salt spray test was explored,the immersion test was conducted and electrochemical test was also executed. The hybrid films exhibited well-pleasing corrosion resistance and adhesion to epoxy resin paints. It was found out that the hybrid films could efficiently be a substitute for chromate based primer over aluminium alloy.

  7. Pyrrolidine analogues of nucleosides and nucleotides

    Rejman, Dominik; Pohl, Radek; Kovačková, Soňa; Kočalka, Petr; Švenková, Alžběta; Šanderová, Hana; Krásný, Libor; Rosenberg, Ivan

    -, č. 52 (2008), s. 577-578. ISSN 0261-3166. [Joint Symposium of the International Roundtable on Nucleosides, Nucleotides and Nucleic Acids /18./ and the International Symposium on Nucleic Acid Chemistry /35./. Kyoto, 08.09.2008-12.09.2008] R&D Projects: GA MŠk(CZ) LC06077; GA MŠk 2B06065; GA MZd NR9138 Institutional research plan: CEZ:AV0Z40550506; CEZ:AV0Z50200510; CEZ:AV0Z50520514 Keywords : pyrrolidine * nucleoside * nucleotide Subject RIV: CC - Organic Chemistry

  8. Thermodynamics and kinetics of thermal decomposition of dibutylalkyl and dipentylalkyl phosphonate-nitric acid systems

    Tributyl phosphate (TBP) is used in the reprocessing industry for the separation of uranium and plutonium from the spent nuclear fuels by PUREX process. A variety of dialkylalky/phosphonates were synthesised and their extraction behaviour on actinides was studied in this laboratory. The superior extraction characteristics of phosphonates make them useful for several metal recovery applications in the nuclear fuel cycle. However, higher solubility of phosphonates in aqueous phase as compared to TBP, introduces higher chances of the formation of thermally active 'red oil' like substances during the evaporation of aqueous streams. Thermal stability of neat and nitric acid solvated homologues of four dibutylalkyl phosphonates namely, dibutylpropyl phosphonate (DBPrP), dibutylbutyl phosphonate (DBBP), dibutylpentyl phosphonate (DBPP), dibutylhexyl phosphonate (DBHeP), and two dipentylalkyl phosphonates viz. dipentylbutyl phosphonate (DPBP), dipentylhexyl phosphonate (DPHeP) were studied. Experiments were conducted using an adiabatic calorimeter in heat-wait-search mode. Various stoichiometry of nitric acid-solvated DBalP and DPalP were prepared by equilibrating the respective organic with 4-15.6 M nitric acid followed by separation. Neat DBalP and DPalP are stable up to the temperature of ∼ 555 K while their acid-solvates decomposed in the temperature range 380-403 K. The results also indicated that the presence of nitric acid accelerated the decomposition of phosphonates. Decomposition of these acid solvated phosphonates is found to be exothermic and follows first order kinetics. The onset temperature, adiabatic temperature rise, pressure rise, decomposition enthalpy and activation energy were found to strongly depend on the nitric acid content of the acid-solvates. The studies also indicate that dibutylalkyl and dipentylalkyl phosphonates are also prone to form 'red oil' like substances under extreme conditions and can lead to run-away reactions

  9. Structural Interactions within Lithium Salt Solvates. Acyclic Carbonates and Esters

    Afroz, Taliman [North Carolina State Univ., Raleigh, NC (United States); Seo, D. M. [North Carolina State Univ., Raleigh, NC (United States); Han, Sang D. [North Carolina State Univ., Raleigh, NC (United States); Boyle, Paul D. [North Carolina State Univ., Raleigh, NC (United States); Henderson, Wesley A. [North Carolina State Univ., Raleigh, NC (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-06

    Solvate crystal structures serve as useful models for the molecular-level interactions within the diverse solvates present in liquid electrolytes. Although acyclic carbonate solvents are widely used for Li-ion battery electrolytes, only three solvate crystal structures with lithium salts are known for these and related solvents. The present work, therefore, reports six lithium salt solvate structures with dimethyl and diethyl carbonate: (DMC)2:LiPF6, (DMC)1:LiCF3SO3, (DMC)1/4:LiBF4, (DEC)2:LiClO4, (DEC)1:LiClO4 and (DEC)1:LiCF3SO3 and four with the structurally related methyl and ethyl acetate: (MA)2:LiClO4, (MA)1:LiBF4, (EA)1:LiClO4 and (EA)1:LiBF4.

  10. PEG-bis phosphonic acid based ionic supramolecular structures

    Gonzalez, Lidia; Skov, Anne Ladegaard; Hvilsted, Søren

    2014-01-01

    A number of supramolecular structures are prepared by mixing stoichiometric amounts of a phosphonic acid terminated poly(ethylene glycol) with propargyl amine, hexamethylene diamine, tris(2-aminoethyl)amine, and the first generation of a poly(propylene imine) dendrimer in turn at room temperature...

  11. New copper aryl phosphonates with auxiliary nitrogen ligands

    Zima, Vítězslav; Svoboda, Jan; Yang, Y.-Ch.; Wang, S.-L.

    2012-01-01

    Roč. 14, č. 10 (2012), s. 3469-3477. ISSN 1466-8033 R&D Projects: GA ČR GA203/08/0208 Institutional research plan: CEZ:AV0Z40500505 Keywords : copper * phosphonates * structure Subject RIV: CA - Inorganic Chemistry Impact factor: 3.879, year: 2012

  12. Intercalation chemistry of layered functionalized phosphonates of tetravalent metals

    Zima, Vítězslav; Melánová, Klára; Svoboda, Jan; Beneš, L.

    Pardubice : University of Pardubice, 2012. s. 117. ISBN 978-80-7395-499-4. [10th International Conference Solid State Chemistry 2012. 10.06.2012-14.06.2012, Pardubice] R&D Projects: GA ČR(CZ) 203/08/0208 Institutional support: RVO:61389013 Keywords : metal phosphonate * layered phosphates * intercalation Subject RIV: CA - Inorganic Chemistry

  13. Layered metal phosphonates as hosts in intercalation chemistry

    Zima, Vítězslav; Beneš, L.; Melánová, Klára; Svoboda, Jan

    Sendai : Tohoku University, 2013. 1-8-1-8. ISBN N. [17th International Symposium on Intercalation Compounds. 12.05.2013-16.05.2013, Sendai] Institutional support: RVO:61389013 Keywords : metal phosphonates * layered materials * intercalation chemistry Subject RIV: CA - Inorganic Chemistry

  14. Flame retardant properties of triazine phosphonates derivative with cotton fabric

    The flame retardant behavior of a cotton fabric treated with phosphorus-nitrogen containing triazine compound was evaluated. It was found that cyanuric chloride (2,4,6-trichloro-1,3,5-triazine) is an excellent starting material for the preparation of phosphonates flame retardants that interacts wel...

  15. Structure-activity-relationships (SAR) in pyrimidine nucleoside transport

    Several series of pyrimidine nucleosides were evaluated as part of a larger program to develop non-invasive brain imaging agents. The interaction of these antitumor/antiviral nucleosides with an NBMPR-sensitive murine erythroctye nucleoside transporter was evaluated by determining their inhibitory effect (Ki) on zero-trans influx of thymidine. Within each series of compounds, which had F, Cl, Br or I as halogen substituents, an increase in size of the halogen atom or a decrease in electronegativity decreased affinity for the transporter. Partition coefficients (P) of these pyrimidine nucleosides were measured to determine their potential to diffuse across the blood-brain-barrier (BBB). Most of the pyrimidine nucleosides had lower P values (log P i for nucleosides with a particular sugar moiety. Within a nucleoside series with a given sugar component, the binding affinity for the transporter was inversely proportional to lipophilicity. 25 refs., 2 tabs., 4 figs

  16. Novel modular approach to C-nucleosides

    Hocek, Michal; Urban, Milan; Joubert, Nicolas

    Kyoto : The Kinki Chemical Society, 2006. s. 183. [International Kyoto Conference on New Aspects of Organic Chemistry /10./. 13.11.2006-17.11.2006, Kyoto] R&D Projects: GA MŠk(CZ) LC512 Institutional research plan: CEZ:AV0Z40550506 Keywords : purines * cross-couplings * nucleosides Subject RIV: CC - Organic Chemistry

  17. Acyclic edge colorings of planar graphs and series-parallel graphs

    2009-01-01

    A proper edge coloring of a graph G is called acyclic if there is no 2-colored cycle in G. The acyclic edge chromatic number of G, denoted by a (G), is the least number of colors in an acyclic edge coloring of G. Alon et al. conjectured that a (G) Δ(G) + 2 for any graphs. For planar graphs G with girth g(G), we prove that a (G) max{2Δ(G) + 2, Δ(G) + 22} if g(G) 3, a (G) Δ(G) + 2 if g(G) 5, a (G) Δ(G) + 1 if g(G) 7, and a (G) = Δ(G) if g(G) 16 and Δ(G) 3. For series-parallel graphs G, we have a (G) Δ(G) + 1.

  18. Acyclic cucurbit[n]uril molecular containers enhance the solubility and bioactivity of poorly soluble pharmaceuticals

    Ma, Da; Hettiarachchi, Gaya; Nguyen, Duc; Zhang, Ben; Wittenberg, James B.; Zavalij, Peter Y.; Briken, Volker; Isaacs, Lyle

    2012-06-01

    The solubility characteristics of 40-70% of new drug candidates are so poor that they cannot be formulated on their own, so new methods for increasing drug solubility are highly prized. Here, we describe a new class of general-purpose solubilizing agents—acyclic cucurbituril-type containers—which increase the solubility of ten insoluble drugs by a factor of between 23 and 2,750 by forming container-drug complexes. The containers exhibit low in vitro toxicity in human liver, kidney and monocyte cell lines, and outbred Swiss Webster mice tolerate high doses of the container without sickness or weight loss. Paclitaxel solubilized by the acyclic cucurbituril-type containers kills cervical and ovarian cancer cells more efficiently than paclitaxel alone. The acyclic cucurbituril-type containers preferentially bind cationic and aromatic drugs, but also solubilize neutral drugs such as paclitaxel, and represent an attractive extension of cyclodextrin-based technology for drug solubilization and delivery.

  19. An Upper Bound for the Adjacent Vertex Distinguishing Acyclic Edge Chromatic Number of a Graph

    Xin-sheng Liu; Ming-qiang An; Yang Gao

    2009-01-01

    A proper k-edge coloring of a graph G is called adjacent vertex distinguishing acyclic edge coloring if there is no 2-colored cycle in G and the color set of edges incident to u is not equal to the color set of edges incident to v,where uv ∈ E(G).The adjacent vertex distinguishing acyclic edge chromatic number of G,denoted by χαα(G),is the minimal number of colors in an adjacent vertex distinguishing acyclic edge coloring of G.In this paper we prove that if G(V,E)is a graph with no isolated edges,then χαα(G)≤32△.

  20. Extraction of uranium from aqueous solution by phosphonic acid-imbedded polyurethane foam

    Phenylphosphonic acid was imbedded into the matrix of the polyurethane foam during the fabrication process of the polymer. The extraction of uranium by phosphonic acid-imbedded polyurethane foam and blank polyurethane (i.e., foam without phosphonic acid functional groups) was investigated. Phosphonic acid-imbedded foam showed superior extractability of uranium from solutions with pH = 7.0 ± 1.5 over a wide range of temperatures. (author)

  1. Seasonal Expression of the Picocyanobacterial Phosphonate Transporter Gene phnD in the Sargasso Sea

    GeorgeSBullerjahn; RobCondon

    2010-01-01

    In phosphorus-limited marine environments, picocyanobacteria (Synechococcus and Prochlorococcus spp.) can hydrolyze naturally occurring phosphonates as a P source. Utilization of 2-aminoethylphosphonate (2-AEP) is dependent on expression of the phn genes, encoding functions required for uptake and C-P bond cleavage. Prior work has indicated that expression of picocyanobacterial phnD, encoding the phosphonate binding protein of the phosphonate ABC transporter, is a proxy for the assimilation...

  2. Synthesis of 1,4-Diazepine Nucleosides

    M Zia-Ul-Haq; Hameed, Shahid

    2002-01-01

    The phenolic b-diketones I prepared by modified Baker-Venkataraman rearrangement were converted to the flavones II in acidic medium which on treatment with aqueous ethylenediamine/propylenediamine gave diazepine derivatives III. After coupling with acetobromo sugars in the presence of mercuric cyanide and nitromethane, deacetylation in methanolic ammonia yielded nucleosides V. The structures of all the intermediates and final products were confirmed with the help of modern spectrosc...

  3. Distribution of Nucleosides in Populations of Cordyceps cicadae

    Wen-Bo Zeng; Hong Yu; Feng Ge; Jun-Yuan Yang; Zi-Hong Chen; Yuan-Bing Wang; Yong-Dong Dai; Alison Adams

    2014-01-01

    A rapid HPLC method had been developed and used for the simultaneous determination of 10 nucleosides (uracil, uridine, 2'-deoxyuridine, inosine, guanosine, thymidine, adenine, adenosine, 2'-deoxyadenosine and cordycepin) in 10 populations of Cordyceps cicadae, in order to compare four populations of Ophicordyceps sinensis and one population of Cordyceps militaris. Statistical analysis system (SAS) 8.1 was used to analyze the nucleoside data. The pattern of nucleoside distribution was analyzed...

  4. Studies on Oxidative Couplings in H-Phosphonate Chemistry

    Nilsson, Johan

    2004-01-01

    In this thesis oxidative coupling of H-phosphonate and H phosphonothioate diesters with different alcohols and amines are presented. Since the reactions with alcohols previously have been particularly unfavourable due to competing side reactions, a modified protocol leading to high coupling yields of structurally diverse hydroxylic components was developed. The phosphorylation reaction was studied using 31P NMR spectroscopy and for the first time the previously only postulated reactive interm...

  5. Phosphonate Biosynthesis and Catabolism: A Treasure Trove of Unusual Enzymology

    Peck, Spencer C.; van der Donk, Wilfred A.

    2013-01-01

    Natural product biosynthesis has proven a fertile ground for the discovery of novel chemistry. Herein we review the progress made in elucidating the biosynthetic pathways of phosphonate and phosphinate natural products such as the antibacterial compounds dehydrophos and fosfomycin, the herbicidal phosphinothricin-containing peptides, and the antimalarial compound FR-900098. In each case, investigation of the pathway has yielded unusual, and often unprecedented, biochemistry. Likewise, recent ...

  6. Synthesis of oligoribonucleotides with phosphonate-modified linkages

    Páv, Ondřej; Kóšiová, Ivana; Barvík, I.; Pohl, Radek; Buděšínský, Miloš; Rosenberg, Ivan

    2011-01-01

    Roč. 9, č. 17 (2011), s. 6120-6126. ISSN 1477-0520 R&D Projects: GA ČR GA202/09/0193; GA AV ČR KAN200520801; GA MŠk(CZ) LC06061 Institutional research plan: CEZ:AV0Z40550506 Keywords : oligoribonucleotide * phosphonate * modified RNA Subject RIV: CC - Organic Chemistry Impact factor: 3.696, year: 2011

  7. Phosphonate biosynthesis and catabolism: a treasure trove of unusual enzymology.

    Peck, Spencer C; van der Donk, Wilfred A

    2013-08-01

    Natural product biosynthesis has proven a fertile ground for the discovery of novel chemistry. Herein we review the progress made in elucidating the biosynthetic pathways of phosphonate and phosphinate natural products such as the antibacterial compounds dehydrophos and fosfomycin, the herbicidal phosphinothricin-containing peptides, and the antimalarial compound FR-900098. In each case, investigation of the pathway has yielded unusual, and often unprecedented, biochemistry. Likewise, recent investigations have uncovered novel ways to cleave the CP bond to yield phosphate under phosphorus starvation conditions. These include the discovery of novel oxidative cleavage of the CP bond catalyzed by PhnY and PhnZ as well as phosphonohydrolases that liberate phosphate from phosphonoacetate. Perhaps the crown jewel of phosphonate catabolism has been the recent resolution of the longstanding problem of the C-P lyase responsible for reductively cleaving the CP bond of a number of different phosphonates to release phosphate. Taken together, the strides made on both metabolic and catabolic fronts illustrate an array of fascinating biochemistry. PMID:23870698

  8. Hierarchical mesostructured titanium phosphonates with unusual uniform lines of macropores.

    Ma, Tian-Yi; Lin, Xiu-Zhen; Zhang, Xue-Jun; Yuan, Zhong-Yong

    2011-04-01

    Organic-inorganic hybrid materials of mesostructured titanium phosphonates with unusual uniform lines of macropores were synthesized by using bis(hexamethylenetriamine) penta(methylenephosphonic acid) (BHMTPMP) as the coupling molecule, through a one-pot hydrothermal process without any surfactant assistance. A wormhole-like mesostructure and many uniform parallel lines of macropores divided by solid ridges in the same direction were confirmed by N(2) sorption, SEM and TEM observations. This novel macropore architecture has never been observed in other metal phosphonate materials, which may be directly related to the structure nature of BHMTPMP with extra long alkyl chains. The structural characterization of FT-IR and MAS NMR revealed the integrity of organic groups inside the hybrid framework. The hybrid materials were also used as adsorbents for heavy metal ions and CO(2), in order to clarify the impacts of the organic contents and organic types on the physicochemical properties of the synthesized hierarchical macro-/mesoporous phosphonate materials. PMID:21344079

  9. Morphology and Proton Transport in Humidified Phosphonated Peptoid Block Copolymers

    2016-01-01

    Polymers that conduct protons in the hydrated state are of crucial importance in a wide variety of clean energy applications such as hydrogen fuel cells and artificial photosynthesis. Phosphonated and sulfonated polymers are known to conduct protons at low water content. In this paper, we report on the synthesis phosphonated peptoid diblock copolymers, poly-N-(2-ethyl)hexylglycine-block-poly-N-phosphonomethylglycine (pNeh-b-pNpm), with volume fractions of pNpm (ϕNpm) values ranging from 0.13 to 0.44 and dispersity (Đ) ≤ 1.0003. The morphologies of the dry block copolypeptoids were determined by transmission electron microscopy and in both the dry and hydrated states by synchrotron small-angle X-ray scattering. Dry samples with ϕNpm > 0.13 exhibited a lamellar morphology. Upon hydration, the lowest molecular weight sample transitioned to a hexagonally packed cylinder morphology, while the others maintained their dry morphologies. Water uptake of all of the ordered samples was 8.1 ± 1.1 water molecules per phosphonate group. In spite of this, the proton conductivity of the ordered pNeh-b-pNpm copolymers ranged from 0.002 to 0.008 S/cm. We demonstrate that proton conductivity is maximized in high molecular weight, symmetric pNeh-b-pNpm copolymers. PMID:27134312

  10. A novel diketo phosphonic acid that exhibits specific, strand-transfer inhibition of HIV integrase and anti-HIV activity

    Chi, Guochen; Nair, Vasu; Semenova, Elena; Pommier, Yves

    2006-01-01

    We have synthesized novel phosphonic acid analogues of β-diketo acids. Interestingly, the phosphonic acid isostere, 2, of our anti-HIV compound, 1, was an inhibitor of only the strand transfer step, in stark contrast to 1. Compound 2 had lower anti-HIV activity than 1, but was more active and less toxic than the phosphonic acid analogue of L-708906. These isosteric compounds represent the first examples of β-diketo phosphonic acids of structural, synthetic and antiviral interest.

  11. Algebraic modelling and performance evaluation of acyclic fork-join queueing networks

    Krivulin, Nikolai K.

    2012-01-01

    Simple lower and upper bounds on mean cycle time in stochastic acyclic fork-join queueing networks are derived using a (max,+)-algebra based representation of network dynamics. The behaviour of the bounds under various assumptions concerning the service times in the networks is discussed, and related numerical examples are presented.

  12. Bounds on mean cycle time in acyclic fork-join queueing networks

    Krivulin, Nikolai K.

    2012-01-01

    Simple lower and upper bounds on mean cycle time in stochastic acyclic fork-join networks are derived using the $(\\max,+)$-algebra approach. The behaviour of the bounds under various assumptions concerning the service times in the networks is discussed, and related numerical examples are presented.

  13. Parallel simulation algorithm for maintenance optimization based on directed Acyclic Graph

    An efficient simulation algorithm for the quantification of reliability performance indicators of a complex system is demonstrated in the paper that is based on Monte Carlo method. A directed Acyclic Graph is used as a useful system representation. A parallel simulation technique is used in the algorithm which is based on the construction of the special course of life sequence of transformed transition times subjected to the corresponding part of the Acyclic Graph. The parts of the Acyclic Graph represent individual subsystems of a given system and may be effectively evaluated from the reliability point of view. The wide range of models for both deterministic and stochastic processes applied on the terminal nodes of the Acyclic Graph is allowed in the algorithm. The use of the algorithm for comparative theoretical calculations as well as for industrial applications is shown by a visual demonstration. A cost-optimization problem is shortly introduced which may be fully solved by the algorithm using additional genetic algorithms as an applicable optimization technique. The problem takes into account also additional objective that is defined as a prescribed constraint of a selected reliability performance indicator. The solution of the cost-optimization problem is demonstrated on two practical examples

  14. CAUSALITY AMONG FED CATTLE MARKET VARIABLES: DIRECTED ACYCLIC GRAPHS ANALYSIS OF CAPTIVE SUPPLY

    Lee, Andrew C.; Kim, Man-Keun

    2004-01-01

    In quantitative research, direction of causality among the variables is often assumed without a rigorous test. In this study, the directed acyclic graph (DAG) method was used to illuminate causal relationships among fed cattle industry variables, in particular, it was shown that captive supply causes spot market price to change.

  15. Carbocyclic pyrimidine nucleosides as inhibitors of S-adenosylhomocysteine hydrolase.

    Mosley, Sylvester L; Bakke, Brian A; Sadler, Joshua M; Sunkara, Naresh K; Dorgan, Kathleen M; Zhou, Zhaohui Sunny; Seley-Radtke, Katherine L

    2006-12-01

    The design, synthesis, and unexpected inhibitory activity against S-adenosyl-homocysteine (SAH) hydrolase (SAHase, EC 3.3.1.1) for a series of truncated carbocyclic pyrimidine nucleoside analogues is presented. Of the four nucleosides obtained, 10 was found to be active with a Ki value of 5.0 microM against SAHase. PMID:16904326

  16. Carbocyclic nucleosides with norbornane pseudosugar moiety locked in North conformation

    Dejmek, Milan; Hřebabecký, Hubert; Šála, Michal; Nencka, Radim

    Crete : University of Crete, 2011. P2.121-P2.121. [ESOC 2011. European Symposium on Organic Chemistry /17./. 10.07.2011-15.07.2011, Crete] R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : norbornane * conformationally lock ed nucleosides * carbocyclic nucleosides Subject RIV: CC - Organic Chemistry

  17. Phosphonates as alternative to tributyl phosphate for the separation of actinides from fission products

    The present work investigates the role of increase in the basicity of organophosphorus extractant (dialkylalkyl phosphonates) on the uptake of actinides and fission products vis-a-vis tributyl phosphate (TBP), currently employed as a universal extractant. Two dialkylalkyl phosphonates viz. dibutylpropyl phosphonate (DBPrP) and dibutylpentyl phosphonate (DBPeP) were synthesized, characterized and evaluated for their solvent extraction behavior towards U(VI), Th(IV), Eu(III) and Tc(VII) in nitric acid medium ranging from 0.01-6 M. It was observed that increasing the basicity of the phosphoryl oxygen enhanced the uptake of the actinides and the distribution coefficient values were significantly larger as compared to TBP. The limiting organic concentration (LOC) value was estimated for Th(IV) for these extractants and compared with the TBP system. The separation factors of actinides with phosphonates over Tc(VII) are distinctly better than that with TBP.

  18. Phosphonates as alternative to tributyl phosphate for the separation of actinides from fission products

    Vyas, Chirag K.; Joshirao, Pranav M.; Manchanda, Vijay K. [Sungkyunkwan Univ., Suwon (Korea, Republic of). Dept. of Energy Science; Rao, C.V.S. Brahmmananda; Jayalakshmi, S. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India). Fuel Chemistry Div.

    2015-06-01

    The present work investigates the role of increase in the basicity of organophosphorus extractant (dialkylalkyl phosphonates) on the uptake of actinides and fission products vis-a-vis tributyl phosphate (TBP), currently employed as a universal extractant. Two dialkylalkyl phosphonates viz. dibutylpropyl phosphonate (DBPrP) and dibutylpentyl phosphonate (DBPeP) were synthesized, characterized and evaluated for their solvent extraction behavior towards U(VI), Th(IV), Eu(III) and Tc(VII) in nitric acid medium ranging from 0.01-6 M. It was observed that increasing the basicity of the phosphoryl oxygen enhanced the uptake of the actinides and the distribution coefficient values were significantly larger as compared to TBP. The limiting organic concentration (LOC) value was estimated for Th(IV) for these extractants and compared with the TBP system. The separation factors of actinides with phosphonates over Tc(VII) are distinctly better than that with TBP.

  19. Structural variations in layered alkaline earth metal cyclohexyl phosphonates

    Ramaswamy Murugavel; Nayanmoni Gogoi

    2009-06-01

    Two series of alkaline earth metal cyclohexyl phosphonates, M(C6H11PO3H)2(H2O) (M = Ca, Sr and Ba) (1–3) and M(C6H11PO3)(H2O) (M = Mg, Ca, Sr, and Ba) (4–7) have been synthesized under mild reaction conditions. All new compounds have been characterized using elemental analysis, IR, TGA and powder X-ray diffraction techniques. The molecular structure of compound 2 determined using single crystal X-ray diffraction technique reveals a layered polymeric structure.

  20. An improved method for the enzymatic transformation of nucleosides into 5'-monophosphates.

    Barai, Vladimir N; Kvach, Sergei V; Zinchenko, Anatoli I; Mikhailopulo, Igor A

    2004-12-01

    An improved method to transform nucleosides into 5'-monophosphates using nucleoside phosphotransferase from Erwinia herbicola is reported. The method is based on the shift in the equilibrium state of the reaction to the formation of desired product due to its precipitation by Zn2+. Under optimal conditions, the extent of nucleoside transformations into nucleoside-5'-monophosphates were 41-91% (mol). PMID:15672226

  1. An Efficient and Facile Methodology for Bromination of Pyrimidine and Purine Nucleosides with Sodium Monobromoisocyanurate (SMBI

    Roger Stromberg

    2013-10-01

    Full Text Available An efficient and facile strategy has been developed for bromination of nucleosides using sodium monobromoisocyanurate (SMBI. Our methodology demonstrates bromination at the C-5 position of pyrimidine nucleosides and the C-8 position of purine nucleosides. Unprotected and also several protected nucleosides were brominated in moderate to high yields following this procedure.

  2. Plasmodium vivax hypoxanthine-guanine phosphoribosyltransferase: A target for anti-malarial chemotherapy

    Keough, D. T.; Hocková, Dana; Krečmerová, Marcela; Česnek, Michal; Holý, Antonín; Naesens, L.; Brereton, I. M.; Winzor, D. J.; de Jersey, J.; Guddat, L. W.

    2010-01-01

    Roč. 173, č. 2 (2010), s. 165-169. ISSN 0166-6851 R&D Projects: GA MŠk 1M0508 Grant ostatní: National Health and Medical Research Council(AU) 569703 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * Plasmodium vivax * 6-oxopurine phosphoribosyltransferase Subject RIV: CC - Organic Chemistry Impact factor: 2.875, year: 2010

  3. Synthesis of purine N9-[2-hydroxy-3-O-(phosphonomethoxy)propyl] derivatives and their side-chain modified analogues as potential antimalarial agents

    Krečmerová, Marcela; Dračínský, Martin; Hocková, Dana; Holý, Antonín; Keough, D. T.; Guddat, L. W.

    2012-01-01

    Roč. 20, č. 3 (2012), s. 1222-1230. ISSN 0968-0896 R&D Projects: GA MŠk 1M0508; GA ČR GAP207/11/0108 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * Malaria * Plasmodium falciparum * Plasmodium vivax * hypoxanthine-guanine-(xanthine)-phosphoribosyltransferase Subject RIV: CC - Organic Chemistry Impact factor: 2.903, year: 2012

  4. Use of 1,3-dioxolanes in the syntheses of alpha-branched alkyl and aryl N-9-[2-(phosphonomethoxy)ethyl]purines

    Pomeisl, Karel; Holý, Antonín; Krečmerová, Marcela

    Praha: Institute of Organic Chemistry and Biochemistry AS CR, v. v. i., 2011 - (Hocek, M.), s. 438-440. (Collection Symposium Series. 12). ISBN 978-80-86241-37-1. [Chemistry of Nucleic Acid Components /15./. Český Krumlov (CZ), 05.06.2011-10.06.2011] R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * dioxolanes * malaria * Mitsunobu reaction Subject RIV: CC - Organic Chemistry

  5. Syntheses of alpha-branched alkyl and aryl N-9-[2-(phoshonomethoxy)ethyl]-purines

    Pomeisl, Karel; Holý, Antonín; Krečmerová, Marcela

    Crete: University of Crete, 2011. P1.163-P1.163. [ESOC 2011. European Symposium on Organic Chemistry /17./. 10.07.2011-15.07.2011, Crete] R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : malaria * acyclic nucleoside phosphonates * dioxolanes * Mitsunobu reaction * hypoxanthine-guanine-xanthine phosphoribosyltransferase Subject RIV: CC - Organic Chemistry

  6. Synthesis and biological properties of the 2’-trifluoromethyl analogues of tenofovir

    Jansa, Petr; Kolman, Viktor; Janeba, Zlatko

    Praha: Institute of Organic Chemistry and Biochemistry AS CR, v. v. i., 2011 - (Hocek, M.), s. 370-371. (Collection Symposium Series. 12). ISBN 978-80-86241-37-1. [Chemistry of Nucleic Acid Components /15./. Český Krumlov (CZ), 05.06.2011-10.06.2011] R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : ANPs * acyclic nucleoside phosphonates * trifluoromethyl group Subject RIV: CC - Organic Chemistry

  7. Efficient one-pot synthesis of polysubstituted 6-[(1H-1,2,3-triazol-1-yl)methyl]uracils through the "click" protocol

    Jansa, Petr; Špaček, Petr; Holý, Antonín; Votruba, Ivan; Janeba, Zlatko

    Praha : Institute of Organic Chemistry and Biochemistry AS CR, v. v. i., 2011 - (Hocek, M.), s. 467-468 ISBN 978-80-86241-37-1. - (Collection Symposium Series. 12). [ Chemistry of Nucleic Acid Components /15./. Český Krumlov (CZ), 05.06.2011-10.06.2011] R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : ANPs * acyclic nucleoside phosphonates * Huisgen cycloaddition * decarboxylation Subject RIV: CC - Organic Chemistry

  8. Introduction of the ethylphosphonate moiety to secondary hydroxyl as a tool for the synthesis of 3-fluoro-2-(phosphonoethoxy)propyl (FPEP) compounds

    Baszczyňski, Ondřej; Jansa, Petr; Hocková, Dana; Janeba, Zlatko; Dračínský, Martin; Holý, Antonín; Keough, D. T.; de Jersey, J.; Guddat, L. W.

    Crete : University of Crete, 2011. -. [ESOC 2011. European Symposium on Organic Chemistry /17./. 10.07.2011-15.07.2011, Crete] R&D Projects: GA MŠk 1M0508; GA ČR GAP207/11/0108 Grant ostatní: National Health and Medicinal Research Council(AU) 569703 Institutional research plan: CEZ:AV0Z40550506 Keywords : phosphorus * acyclic nucleoside phosphonates * biological activities * fluorine * Michael addition Subject RIV: CC - Organic Chemistry

  9. Pd-catalyzed Suzuki-Miyaura coupling reaction in the synthesis of 5-aryl-1-[2-(phosphonomethoxy)ethyl]uracils as potential multisubstrate inhibitors of thymidine phosphorylase

    Pomeisl, Karel; Holý, Antonín; Pohl, Radek

    2007-01-01

    Roč. 48, č. 17 (2007), s. 3065-3067. ISSN 0040-4039 R&D Projects: GA MŠk 1M0508 Grant ostatní: Descartes Prize(XE) HPAW-CT-2002-9001 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * thymidine phosphorylase * Suzuki coupling * pyrimidine Subject RIV: CC - Organic Chemistry Impact factor: 2.615, year: 2007

  10. Syntheses of base and side-chain modified pyrimidine 1-[2-(phosphonomethoxy)propyl] derivatives as potent inhibitors of thymidine phosphorylase (PD-ECGF) from SD-lymphoma

    Pomeisl, Karel; Votruba, Ivan; Holý, Antonín; Pohl, Radek

    2006-01-01

    Roč. 71, č. 4 (2006), s. 595-624. ISSN 0010-0765 R&D Projects: GA ČR(CZ) GA203/03/0089 Grant ostatní: Descartes Prize(US) HPAW-CT-2002-9001 Institutional research plan: CEZ:AV0Z40550506 Keywords : acyclic nucleoside phosphonates * thymidine phosphorylase * fluorination * pyrimidines Subject RIV: CC - Organic Chemistry Impact factor: 0.881, year: 2006