Furan-Based Porphyrins: Tetraoxa[4n+2]porphyrin Dications with 18π-, 22π-, or 26π-Electron Systems

Vogel, Emanuel; Jux, Norbert; Dörr, Joachim; Pelster, Thomas; Berg, Thorsten; Böhm, Horst-Stefan; Behrens, Frank; Lex, Johann; Bremm, Dominik; Hohlneicher, Georg

doi:10.1002/(sici)1521-3773(20000317)39:6<1101::aid-anie1101>3.0.co;2-f

Cited by 41 publications

(27 citation statements)

References 12 publications

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“…The extreme downfield and upfield positions of the resonances of the outside and inside perimeter protons, respectively, confirm the aromaticity of this expanded porphyrinoid. The rough aromaticity measure Δ δ , defined as the greatest difference between chemical shifts of the outer and inner protons, equals 19.12 ppm, which is close to the Δ δ range of 20–23 ppm observed for planar [22]porphyrins . The signals broadening, visible in Figure A, is a result of dynamic equilibria in solution, where interactions with anions and water play an important role (see below).…”

Section: Resultssupporting

confidence: 57%

Shaping a Porphyrinoid Frame by Heteroatoms Extrusion: Formation of an Expanded [22]Triphyrin(6.6.0)

Pacholska‐Dudziak

Latos‐Grażyński

Białońska

2019

Chemistry A European J

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An aromatic expanded triphyrin, [22]triphyrin(6.6.0) 2, containing a pyrrole unit, a bipyrrole moiety, and annulene links, was obtained from a tellurium‐containing precursor meso‐tetraaryl‐26,28‐ditellurasapphyrin 1. The reaction path proceeds through an acid‐promoted tellurium extrusion from 1 yielding directly 2, characterized in a dicationic form by X‐ray crystallography. In solution the neutral macrocycle 2 reveals flexibility typical for annulenes and it exists as a mixture of conformers that differ by the configuration of the annulene fragments, as proven by 1H NMR studies and analyzed by DFT methods. The conformation is controlled by protonation state, the nature of an interacting anion, solvent identity, and by interaction with water.

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Section: Resultssupporting

confidence: 57%

Shaping a Porphyrinoid Frame by Heteroatoms Extrusion: Formation of an Expanded [22]Triphyrin(6.6.0)

Pacholska‐Dudziak

Latos‐Grażyński

Białońska

2019

Chemistry A European J

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“…Extension of the porphycene core, as in 22π and 26π acetylene-cumulene porphycenes, also shows a clear red-shift pattern, consistent with the increased size of the conjugation pathway from 18 to 22 and 26 π electrons, respectively [78,179]. Finally, red shifts can also be induced by introduction of heteroatoms in the porphycene core [92,110,[115][116][117][118][119][120].…”

Section: Absorption Spectramentioning

confidence: 56%

“…Finally, red shifts can also be induced by introduction of heteroatoms in the porphycene core [92,110,[115][116][117][118][119][120]. The batho-and hyperchromic effects brought about by aza substitution in porphyrins encouraged exploration of whether such effects would also occur in porphycenes.…”

Section: The Ideal Pdt Sensitizermentioning

confidence: 99%

Porphycenes: Facts and Prospects in Photodynamic Therapy of Cancer

Stockert¹,

Cañete²,

Juarranz³

et al. 2007

CMC

177

130

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The photodynamic process induces cell damage and death by the combined effect of a photosensitizer (PS), visible light, and molecular oxygen, which generate singlet oxygen ((1)O(2)) and other reactive oxygen species that are responsible for cytotoxicity. The most important application of this process with increasing biomedical interest is the photodynamic therapy (PDT) of cancer. In addition to hematoporphyrin-based drugs, 2nd generation PSs with better photochemical properties are now studied using cell cultures, experimental tumors and clinical trials. Porphycene is a structural isomer of porphyrin and constitutes an interesting new class of PS. Porphycene derivatives show higher absorption than porphyrins in the red spectral region (lambda > 600 nm, epsilon > 50000 M-(1)cm(-1)) owing to the lower molecular symmetry. Photophysical and photobiological properties of porphycenes make them excellent candidates as PSs, showing fast uptake and diverse subcellular localizations (mainly membranous organelles). Several tetraalkylporphycenes and the tetraphenyl derivative (TPPo) induce photodamage and cell death in vitro. Photodynamic treatments of cultured tumor cells with TPPo and its palladium(II) complex induce cytoskeletal changes, mitotic blockage, and dose-dependent apoptotic or necrotic cell death. Some pharmacokinetic and phototherapeutic studies on experimental tumors after intravenous or topical application of lipophilic alkyl-substituted porphycene derivatives are known. Taking into account all these features, porphycene PSs should be very useful for PDT of cancer and other biomedical applications.

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“…An acetylenic carbon chain as a construction element of porphyrinoids has been employed to enlarge these macrocycles [50,51]. In triphyrin 18, one pyrrole is replaced by the -C≡C-element which is given a chance to get close to a coordinated metal ion [42].…”

Section: Triphyrinsmentioning

confidence: 99%