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  1. Article ; Online: Push-pull quinoidal porphyrins.

    Smith, Martin J / Blake, Iain M / Clegg, William / Anderson, Harry L

    Organic & biomolecular chemistry

    2018  Volume 16, Issue 19, Page(s) 3648–3654

    Abstract: A family of push-pull quinoidal porphyrin monomers has been prepared from a meso-formyl porphyrin by bromination, thioacetal formation, palladium-catalyzed coupling with malononitrile and oxidation with DDQ. Attempts at extending this synthesis to a push- ...

    Abstract A family of push-pull quinoidal porphyrin monomers has been prepared from a meso-formyl porphyrin by bromination, thioacetal formation, palladium-catalyzed coupling with malononitrile and oxidation with DDQ. Attempts at extending this synthesis to a push-pull quinoidal/cumulenic porphyrin dimer were not successful. The crystal structures of the quinoidal porphyrins indicate that there is no significant contribution from singlet biradical or zwitterionic resonance forms. The crystal structure of an ethyne-linked porphyrin dimer shows that the torsion angle between the porphyrin units is only about 3°, in keeping with crystallographic results on related compounds, but contrasting with the torsion angle of about 35° predicted by computational studies. The free-base quinoidal porphyrin monomers form tightly π-stacked layer structures, despite their curved geometries and bulky aryl substituents.
    Language English
    Publishing date 2018-04-30
    Publishing country England
    Document type Journal Article
    ZDB-ID 2097583-1
    ISSN 1477-0539 ; 1477-0520
    ISSN (online) 1477-0539
    ISSN 1477-0520
    DOI 10.1039/c8ob00491a
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Publisher Correction: A new fundamental type of conformational isomerism.

    Canfield, Peter J / Blake, Iain M / Cai, Zheng-Li / Luck, Ian J / Krausz, Elmars / Kobayashi, Rika / Reimers, Jeffrey R / Crossley, Maxwell J

    Nature chemistry

    2018  Volume 10, Issue 9, Page(s) 989

    Abstract: In the version of this Article originally published, the word 'stereoisomerism' was erroneously included in the label of the upper-right box of Fig. 1. The label within the box has been corrected and it now reads: "Constitutional isomerism (same formula, ...

    Abstract In the version of this Article originally published, the word 'stereoisomerism' was erroneously included in the label of the upper-right box of Fig. 1. The label within the box has been corrected and it now reads: "Constitutional isomerism (same formula, different connectivity)". This has been corrected in the online version of the Article.
    Language English
    Publishing date 2018-07-18
    Publishing country England
    Document type Journal Article ; Published Erratum
    ZDB-ID 2464596-5
    ISSN 1755-4349 ; 1755-4330
    ISSN (online) 1755-4349
    ISSN 1755-4330
    DOI 10.1038/s41557-018-0117-5
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: A new fundamental type of conformational isomerism.

    Canfield, Peter J / Blake, Iain M / Cai, Zheng-Li / Luck, Ian J / Krausz, Elmars / Kobayashi, Rika / Reimers, Jeffrey R / Crossley, Maxwell J

    Nature chemistry

    2018  Volume 10, Issue 6, Page(s) 615–624

    Abstract: Isomerism is a fundamental chemical concept, reflecting the fact that the arrangement of atoms in a molecular entity has a profound influence on its chemical and physical properties. Here we describe a previously unclassified fundamental form of ... ...

    Abstract Isomerism is a fundamental chemical concept, reflecting the fact that the arrangement of atoms in a molecular entity has a profound influence on its chemical and physical properties. Here we describe a previously unclassified fundamental form of conformational isomerism through four resolved stereoisomers of a transoid (BF)O(BF)-quinoxalinoporphyrin. These comprise two pairs of enantiomers that manifest structural relationships not describable within existing IUPAC nomenclature and terminology. They undergo thermal diastereomeric interconversion over a barrier of 104 ± 2 kJ mol
    Language English
    Publishing date 2018-05-21
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2464596-5
    ISSN 1755-4349 ; 1755-4330
    ISSN (online) 1755-4349
    ISSN 1755-4330
    DOI 10.1038/s41557-018-0043-6
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Synthetically tuneable biomimetic artificial photosynthetic reaction centres that closely resemble the natural system in purple bacteria.

    Lee, Sai-Ho / Blake, Iain M / Larsen, Allan G / McDonald, James A / Ohkubo, Kei / Fukuzumi, Shunichi / Reimers, Jeffrey R / Crossley, Maxwell J

    Chemical science

    2016  Volume 7, Issue 10, Page(s) 6534–6550

    Abstract: Porphyrin-based photosynthetic reaction centre (PRC) mimics, ...

    Abstract Porphyrin-based photosynthetic reaction centre (PRC) mimics,
    Language English
    Publishing date 2016-06-16
    Publishing country England
    Document type Journal Article
    ZDB-ID 2559110-1
    ISSN 2041-6539 ; 2041-6520
    ISSN (online) 2041-6539
    ISSN 2041-6520
    DOI 10.1039/c6sc01076h
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Finding the missing millions - the impact of a locally enhanced service for COPD on current and projected rates of diagnosis: a population-based prevalence study using interrupted time series analysis.

    Falzon, Christine / Soljak, Michael / Elkin, Sarah L / Blake, Iain D / Hopkinson, Nicholas S

    Primary care respiratory journal : journal of the General Practice Airways Group

    2012  Volume 22, Issue 1, Page(s) 59–63

    Abstract: Background: Many patients with chronic obstructive pulmonary disease (COPD) are not identified until their condition is relatively advanced and there is a considerable gap between the modelled and diagnosed prevalence of the disease. We have previously ... ...

    Abstract Background: Many patients with chronic obstructive pulmonary disease (COPD) are not identified until their condition is relatively advanced and there is a considerable gap between the modelled and diagnosed prevalence of the disease. We have previously shown that, in the first year after the introduction of a locally enhanced service (LES) for COPD in 2008, there was a significant step-up in the diagnosed prevalence.
    Aims: To investigate whether this initial increase in prevalence was sustained, and the impact of this increase on future projected rates of COPD diagnosis.
    Methods: Using data from 2005-2011, we compared the prevalence of diagnosed COPD in the LES Primary Care Trust (LES-PCT) before and after it was introduced. Data were compared with a neighbouring PCT, the London Strategic Health Authority, and England. The true prevalence of COPD was estimated based on data from the Health Survey for England. Trends were extrapolated to estimate the proportion of patients that would be diagnosed in 2017.
    Results: The introduction of the LES was associated with a significant acceleration in the annual increase in diagnosed COPD (p<0.0001). By 2011 the prevalence was 1.17% in the LES-PCT compared with a predicted value of 0.91% (95% CI 0.86% to 0.95%) based on the pre-LES trend. There was no change in the rate of increase in COPD prevalence for the neighbouring PCT or for London as a whole. The LES-PCT would be expected to diagnose 55.6% of COPD patients by 2017 compared with only 27.3% without the LES, and only 33.3% would be diagnosed in the neighbouring PCT.
    Conclusions: These data suggest that, with appropriate incentives, it is possible to achieve a sustained improvement in COPD case-finding in primary care and that such policies need to be implemented systematically.
    MeSH term(s) Humans ; Prevalence ; Pulmonary Disease, Chronic Obstructive/diagnosis ; Pulmonary Disease, Chronic Obstructive/epidemiology ; Time Factors
    Language English
    Publishing date 2012-10-05
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2129033-7
    ISSN 1475-1534 ; 1475-1534
    ISSN (online) 1475-1534
    ISSN 1475-1534
    DOI 10.4104/pcrj.2013.00008
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Can financial incentives for improvements in healthcare quality enhance identification of COPD in primary care?

    Falzon, Christine / Elkin, Sarah L / Kelly, Julia L / Lynch, Frankie / Blake, Iain D / Hopkinson, Nicholas S

    Thorax

    2011  Volume 66, Issue 7, Page(s) 630

    MeSH term(s) Humans ; London ; Primary Health Care/standards ; Pulmonary Disease, Chronic Obstructive/diagnosis ; Quality Improvement/economics ; Reimbursement, Incentive
    Language English
    Publishing date 2011-07
    Publishing country England
    Document type Letter ; Research Support, Non-U.S. Gov't
    ZDB-ID 204353-1
    ISSN 1468-3296 ; 0040-6376
    ISSN (online) 1468-3296
    ISSN 0040-6376
    DOI 10.1136/thx.2010.140913
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    In stock of ZB MED Cologne/Königswinter

    Ui III Zs.83: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular
    ab Jg. 2022: Lesesaal (EG)

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  7. Article ; Online: Regioselective reactivity of an asymmetric tetravalent di[dihydroxotin(IV)] bis-porphyrin host driven by hydrogen-bond templation.

    Brotherhood, Peter R / Luck, Ian J / Blake, Iain M / Jensen, Paul / Turner, Peter / Crossley, Maxwell J

    Chemistry (Weinheim an der Bergstrasse, Germany)

    2008  Volume 14, Issue 35, Page(s) 10967–10977

    Abstract: Local molecular environment effects on the rates of ligand exchange at an asymmetric di[dihydroxotin(IV)] bis-porphyrin 5 are examined. The host 5 possesses four non-equivalent tin(IV)-ligand binding sites that are distinguished by their position ... ...

    Abstract Local molecular environment effects on the rates of ligand exchange at an asymmetric di[dihydroxotin(IV)] bis-porphyrin 5 are examined. The host 5 possesses four non-equivalent tin(IV)-ligand binding sites that are distinguished by their position relative to a shallow cavity, by the steric environment at each binding site and by electronic-structure differences between the constituent porphyrin and quinoxalinoporphyrin macrocycles. These design features of the asymmetric host are confirmed by X-ray crystal structure analysis. Binding experiments with monodentate carboxylic acids and bidentate dicarboxylic acids show significant differences in the rate of ligand exchange at each of the four tin(IV) binding sites. For monodentate carboxylic acids, binding preferentially occurs at the exterior porphyrin site. Further addition of carboxylic acid results in sequential binding at the quinoxalinoporphyrin sites and lastly at the interior site on the porphyrin, with high regioselectivity. These selective binding outcomes are immediately apparent by NMR spectroscopy. A series of 2D NMR spectroscopy experiments allowed identification of the preferred binding sites at the host. This positively identifies that steric hindrance and electron-withdrawing functionality on the porphyrin macrocycle impede ligand exchange. However, these effects are overcome by dicarboxylic acid guests, which form ditopic hydrogen-bond interactions between the intracavity hydroxo ligands in the initial stage of ligand exchange, leading to regioselective binding between the tin(IV) sites within the cavity. It is envisaged that the factors identified herein that define regioselective ligand exchange at host 5 will find wider application in supramolecular systems incorporating tin(IV) porphyrins.
    MeSH term(s) Binding Sites ; Crystallography, X-Ray ; Dicarboxylic Acids/chemistry ; Hydrogen Bonding ; Kinetics ; Ligands ; Magnetic Resonance Spectroscopy ; Metalloporphyrins/chemistry ; Tin/chemistry
    Chemical Substances Dicarboxylic Acids ; Ligands ; Metalloporphyrins ; Tin (7440-31-5)
    Language English
    Publishing date 2008
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1478547-x
    ISSN 1521-3765 ; 0947-6539
    ISSN (online) 1521-3765
    ISSN 0947-6539
    DOI 10.1002/chem.200801775
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: [No title information]

    Webb, James E. / Maharaj, Felicia / Blake, Iain M. / Crossley, Maxwell J.

    Synlett

    2008  Volume 2008, Issue 14, Page(s) 2147–2149

    Abstract: Synthesis of a new ‘capped’ porphyrin 3 with rigid 1,2,3-triazole linkers between the porphyrin and ‘capping’ group has been achieved. A ‘click’ reaction, the copper(I)-catalysed variant of the Huisgen 1,3-dipolar cycloaddition, is used to create four ... ...

    Abstract Synthesis of a new ‘capped’ porphyrin 3 with rigid 1,2,3-triazole linkers between the porphyrin and ‘capping’ group has been achieved. A ‘click’ reaction, the copper(I)-catalysed variant of the Huisgen 1,3-dipolar cycloaddition, is used to create four linkages concomitantly under anhydrous conditions in N,N-dimethylformamide.
    Keywords porphyrin ; alkyne ; azide ; 1,2,3-triazoles
    Language English
    Publishing date 2008-07-02
    Publishing place Stuttgart ; New York
    Document type Article
    ZDB-ID 2042012-2
    ISSN 1437-2096 ; 0936-5214
    ISSN (online) 1437-2096
    ISSN 0936-5214
    DOI 10.1055/s-2008-1077899
    Database Thieme publisher's database

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  9. Article: Fusion and planarization of a quinoidal porphyrin dimer.

    Blake, Iain M / Krivokapic, Alexander / Katterle, Martin / Anderson, Harry L

    Chemical communications (Cambridge, England)

    2002  , Issue 16, Page(s) 1662–1663

    Abstract: The crystal structure, near-infrared spectrum and electrochemistry of a quinoidal triply-linked porphyrin dimer are compared with those of its singly-linked precursor; fusing the two porphyrins planarizes the pi-system and reduces the optical HOMO-LUMO ... ...

    Abstract The crystal structure, near-infrared spectrum and electrochemistry of a quinoidal triply-linked porphyrin dimer are compared with those of its singly-linked precursor; fusing the two porphyrins planarizes the pi-system and reduces the optical HOMO-LUMO gap while increasing the gap between the first oxidation and reduction potentials.
    Language English
    Publishing date 2002-10-01
    Publishing country England
    Document type Journal Article
    ZDB-ID 1472881-3
    ISSN 1364-548X ; 1359-7345 ; 0009-241X
    ISSN (online) 1364-548X
    ISSN 1359-7345 ; 0009-241X
    DOI 10.1039/b204265g
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Fusion and planarization of a quinoidal porphyrin dimer

    Blake, Iain M / Krivokapic, Alexander / Katterle, Martin / Anderson, Harry L

    Chemical communications. 2002 July 26, , no. 16

    2002  

    Abstract: The crystal structure, near-infrared spectrum and electrochemistry of a quinoidal triply-linked porphyrin dimer are compared with those of its singly-linked precursor; fusing the two porphyrins planarizes the π-system and reduces the optical HOMO–LUMO ... ...

    Abstract The crystal structure, near-infrared spectrum and electrochemistry of a quinoidal triply-linked porphyrin dimer are compared with those of its singly-linked precursor; fusing the two porphyrins planarizes the π-system and reduces the optical HOMO–LUMO gap while increasing the gap between the first oxidation and reduction potentials.
    Keywords crystal structure ; electrochemistry ; oxidation ; porphyrins
    Language English
    Dates of publication 2002-0726
    Size p. 1662-1663.
    Publishing place The Royal Society of Chemistry
    Document type Article
    ZDB-ID 1472881-3
    ISSN 1364-548X ; 1359-7345 ; 0009-241X
    ISSN (online) 1364-548X
    ISSN 1359-7345 ; 0009-241X
    DOI 10.1039/b204265g
    Database NAL-Catalogue (AGRICOLA)

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