Journal articles: 'Porphyrin compounds'

1

Egemen, Gamze, Mustafa Hayvalı, Zeynel Kılıç, A. Osman Solak, and Zafer Üstündağ. "Phosphorus-nitrogen compounds Part 17: The synthesis, spectral and electrochemical investigations of porphyrino-phosphazenes." Journal of Porphyrins and Phthalocyanines 14, no. 03 (March 2010): 227–34. http://dx.doi.org/10.1142/s1088424610001945.

Full text

Abstract:

The reactions of unsymmetrical porphyrins (1 and 2) with Ni(OAc)2·4H2O in boiling DMF produce porphyrin complexes (3 and 4). From the reactions of free porphyrin ligands 1 and 2 with hexachlorocyclotriphosphazatriene, N3P3Cl6 , the new free porphyrino-phosphazene derivatives (5 and 6) are obtained. On the other hand, the reactions of N3P3Cl6 with porphyrin complexes (3 and 4) afford the new porphyrino-phosphazene complexes (7 and 8). In the literature there are a few examples of the porphyrino-phosphazene architectures. The structural investigations of all the compounds have been made by elemental analyses, MS, FTIR, 1H NMR, 31P NMR and UV-visible techniques. The cyclic voltammograms (CVs) are examined in acetonitrile (MeCN) containing 0.1 M tetrabutylammonium-tetrafluoroborate (TBATFB) to investigate the surface attachment properties at the glassy carbon electrode (GCE) and the influence of the presence of metal cations in the porphyrin ring.

APA, Harvard, Vancouver, ISO, and other styles

2

Uemori, Yoshio, Masato Sakurai, Atsuko Osada, Hiroki Munakata, Hiroyasu Imai, and Shigeo Nakagawa. "Synthesis and properties of water-soluble porphyrins bearing multidentate ligands." Journal of Porphyrins and Phthalocyanines 08, no. 08 (August 2004): 1047–54. http://dx.doi.org/10.1142/s1088424604000416.

Full text

Abstract:

Water-soluble porphyrins bearing multidentate ligands were prepared by covalent binding of nitrilotriacetic acid to 5,10,15,20-tetrakis(4-aminophenyl)porphyrin or three atropisomers of 5,10,15,20-tetrakis(2-aminophenyl)porphyrin. The acid-base properties and monomer-dimer behavior of the porphyrins were affected by the positions of the multidentate ligands with respect to the porphyrin plane. Among the porphyrins, the porphyrin bearing multidentate ligands at the para position of the phenyl groups dimerized in an aqueous solution. The association constants of the porphyrins with various aromatic compounds were studied in water at pH 7.4 containing 10 mM HEPES at 25°C. These values varied with the structure and charges of both the porphyrins and the aromatic compounds. The association constants of the porphyrin bearing multidentate ligands at the 2-position of the phenyl groups were small compared to those of the porphyrin bearing multidentate ligands at the 4-position.

APA, Harvard, Vancouver, ISO, and other styles

3

Senge, Mathias O., and Mia Davis. "Porphyrin (porphine) — A neglected parent compound with potential." Journal of Porphyrins and Phthalocyanines 14, no. 07 (July 2010): 557–67. http://dx.doi.org/10.1142/s1088424610002495.

Full text

Abstract:

Porphine is the parent compound of a family of biologically and chemically relevant compounds called porphyrins. The potential of these compounds is enormous and it would be advantageous to use the porphine (porphyrin) unit as a building block for the synthesis of diverse porphyrin complexes with a wide range of applications. However, despite first being synthesized over 70 years ago, porphine has not been utilized to its full extent due to low yield syntheses and poor solubility. Recent advances have now overcome many of these problems. The purpose of this review is to illustrate the advances made in porphine chemistry to illustrate the inherent potential of this simple compound.

APA, Harvard, Vancouver, ISO, and other styles

4

Neagu, Monica, Gina Manda, Carolina Constantin, Eugen Radu, and Rodica-Mariana Ion. "Synthetic porphyrins in experimental photodynamic therapy induce a different antitumoral effect." Journal of Porphyrins and Phthalocyanines 11, no. 01 (January 2007): 58–65. http://dx.doi.org/10.1142/s1088424607000084.

Full text

Abstract:

The aim of the study was to investigate the influence of discrete structural differences in synthetic porphyrins on the antineoplastic effect induced in myelocitic cell line K562 after experimental photodynamic therapy procedure. For this study, we used 5,10,15,20-tetra(1-naphthyl)porphyrin, 5,10,15,20-tetra(4-sulfonatophenyl)porphyrin and their Zn complexes. For all these compounds, the following photodynamic therapy parameters were optimized: cell concentration, dye loading concentration, loading time and irradiation procedure. The non-toxic doses of porphyrins were different according to their structure: for 5,10,15,20-tetra(1-naphthyl)porphyrin compounds, the dose was of 10 μg.mL-1, and for 5,10,15,20-tetra(4-sulfonatophenyl)porphyrin compounds, the dose was 20 μg.mL-1. Cell functionality was assessed as membrane integrity, viability, and number of metabolically active cells. Photodynamic cell degradation kinetics showed that during irradiation tumor cells are actively destroyed, in contrast to unloaded cells. K562 cells loaded with the above-mentioned compounds and subjected to irradiation, displayed lower proliferative capacity compared to the control, for a period of 72 h after irradiation. The proliferative capacity of K562 cell line was more strongly inhibited by the 5,10,15,20-tetra(1-naphthyl)porphyrin family of compounds than by the 5,10,15,20-tetra(4-sulfonatophenyl)porphyrin family. The tested synthetic porphyrins showed effective antineoplastic activity against K562 leukemia cells in our in vitro photodynamic therapy experimental model.

APA, Harvard, Vancouver, ISO, and other styles

5

Ou, Zhongping, Xueyan Chen, Lina Ye, Songlin Xue, Yuanyuan Fang, Xiaoqin Jiang, and Karl M. Kadish. "N-confusedmeso-tetraaryl-substituted free-base porphyrins: determination of protonation and deprotonation constants in nonaqueous media." Journal of Porphyrins and Phthalocyanines 19, no. 01-03 (January 2015): 251–60. http://dx.doi.org/10.1142/s1088424614501132.

Full text

Abstract:

The protonation and deprotonation reactions for a series N-confused meso-tetraaryl-substituted free-base porphyrins containing electron-donating or electron-withdrawing substituents was monitored in CHCl3and DMF by UV-visible spectroscopy during titrations with trifluoroacetic acid or tetra-n-butylammonium hydroxide. The spectroscopic data was also used to calculate equilibrium constants for these reactions. The examined compounds are represented as (XPh)4NCPH2, where "NCP" represents the N-confused porphyrin π-conjugated macrocycle and X is a CH3O , CH3, H or Cl para-substituent on the four meso-phenyl rings (Ph) of the compound. The porphyrins can exist in two tautomeric forms depending upon the solvent and each tautomer undergoes two stepwise protonation reactions leading to formation of the mono- and bis-protonated porphyrins, [(XPh)4NCPH3]+and [(XPh)4NCPH4]2+. A single step deprotonation is observed for the same compounds in DMF and the product is assigned as [(XPh)4NCPH]-. Comparisons are made between UV-visible spectra of the protonated, neutral and deprotonated forms of the porphyrin and the effect of the porphyrin ring substituents and tautomeric form of the neutral porphyrin on the UV-visible spectra and protonation constants is discussed along with data from DFT calculations.

APA, Harvard, Vancouver, ISO, and other styles

6

Espitia-Almeida, Fabián, Carlos Diaz-Uribe, William Vallejo, Doris Gómez-Camargo, Arnold R. Romero Bohórquez, and Cristian Linares-Flores. "Photophysical study and in vitro approach against Leishmania panamensis of dicloro-5,10,15,20-tetrakis(4-bromophenyl)porphyrinato Sn(IV)." F1000Research 10 (July 1, 2021): 379. http://dx.doi.org/10.12688/f1000research.52433.2.

Full text

Abstract:

Background: Photodynamic therapy activity against different biological systems has been reported for porphyrins. Porphyrin modifications through peripheral groups and/or by metal insertion inside the ring are main alternatives for the improvement of its photo-physical properties. In this study, we synthesized and characterized 5,10,15,20-tetrakis(4-bromophenyl)porphyrin and the dicloro-5,10,15,20-tetrakis(4-bromophenyl)porphyrinato Sn(IV). Methods: Metal-free porphyrin was synthesized using the Alder method, while the Sn(IV)-porphyrin complex was prepared by combining metal-free porphyrin with stannous chloride in DMF; the reaction yields were 47% and 64% respectively. Metal-free porphyrin was characterized by UV-Vis, FT-IR, ESI-mass spectrometry and 13C-NMR. Additionally, the Sn(IV) -porphyrin complex was characterized using UV-Vis and FT-IR. Cyclic voltammetry tests in four different solvents. The fluorescence quantum yield (Φf) was measured using fluorescein as a standard, the singlet oxygen quantum yield (ΦD) was estimated using the standard 5,10,15,20-(tetraphenyl)porphyrin (H2TPP) and the quencher of singlet oxygen 1,3-diphenylisobenzofuran (DPBF). Results: UV-Vis assay showed typical Q and Soret bands for porphyrin and its metallo-porphyrin complex. Compounds showed photoluminescence at the visible range of electromagnetic spectrum. The inclusion of the metal in the porphyrin core changed the Φf from 0.15 to 0.05 and the ΦD increased from 0.55 to 0.59. Finally, the effect of the compounds on the viability of L. panamensis was evaluated by means of the MTT test. The results showed that both compounds decreased the viability of the parasite; this inhibitory activity was greater under light irradiation; the porphyrin compound had IC50 of 16.5 μM and the Sn(IV)-porphyrin complex had IC50 of 19.2 μM. Conclusion: The compounds were synthesized efficiently, their characterization was carried out by different spectroscopy techniques and their own signals were evidenced for both structures, both compounds decreased the cell viability of L. panamensis.

APA, Harvard, Vancouver, ISO, and other styles

7

Oliveira, Anabela Sousa, Dumitru Licsandru, Rica Boscencu, Radu Socoteanu, Veronica Nacea, and Luis Filipe Vieira Ferreira. "A Singlet Oxygen Photogeneration and Luminescence Study of Unsymmetrically Substituted Mesoporphyrinic Compounds." International Journal of Photoenergy 2009 (2009): 1–10. http://dx.doi.org/10.1155/2009/413915.

Full text

Abstract:

This paper deals with a series of new unsymmetrically substituted mesoporphyrins: 5-(2-hydroxyphenyl)-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHO), 5-(3-hydroxyphenyl)-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHM), 5-(4-hydroxyphenyl)-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHP), 5-(2-hydroxyphenyl)-10,15,20-tris-butyl-21,23-H-porphyrin (TBPOHO), and their parent nonsubstituted compounds, respectively, 5,10,15,20-tetrakis-phenyl-21,23-H-porphyrin (TPP) and 5,10,15,20-tetrakis-butyl-21,23-H-porphyrin (TBP). Several photophysical studies were carried out to access the influence of the unsymmetrical substitution at the porphyrinic macrocycle on porthyrin's photophysical properties, especially porthyrin's efficiency as singlet oxygen sensitizers. The quantum yields of singlet oxygen generation were determined in benzene (ΦΔ(TPP) = 0.66 ± 0.05;ΦΔ(TPPOHO) = 0.69 ± 0.04;ΦΔ(TPPOHM) = 0.62 ± 0.04;ΦΔ(TPPOHP) = 0.73 ± 0.03;ΦΔ(TBP) = 0.76 ± 0.03;ΦΔ(TBPOHO) = 0.73 ± 0.02) using the 5,10,15,20-tetraphenyl-21,23-H-porphine (ΦΔ(TPP) = 0.66) and Phenazine (ΦΔ(Phz) = 0.83) as reference compounds. Their fluorescence quantum yields were found to be (Φf(TPPOHO) = 0.10 ± 0.04;Φf(TPPOHM) = 0.09 ± 0.03;Φf(TPPOHP) = 0.13 ± 0.02;Φf(TBP) = 0.08 ± 0.03 andΦf(TBPOHO) = 0.08 ± 0.02 using 5,10,15,20-tetraphenyl-21,23-H-porphine as referenceΦf(TPP) = 0.13). Singlet state lifetimes were also determined in the same solvent. All the porphyrins presented very similar fluorescence lifetimes (mean values ofτS(withO2, air equilibrated) = 9.6 ± 0.3 nanoseconds and (withoutO2, argon purged) = 10.1 ± 0.6 nanoseconds, resp.). The phosphorescence emission was found to be negligible for this series of unsymmetrically substituted mesoporphyrins, but an E-type, thermally activated, delayed fluorescence process was proved to occur at room temperature.

APA, Harvard, Vancouver, ISO, and other styles

8

Quan, Gia Co, Morgane Denis, Brian Abeykoon, Jean-Bernard Tommasino, Erwann Jeanneau, Catherine Journet, Thomas Devic, and Alexandra Fateeva. "Supramolecular assemblies of phenolic metalloporphyrins: Structures and electrochemical studies." Journal of Porphyrins and Phthalocyanines 23, no. 01n02 (January 2019): 103–16. http://dx.doi.org/10.1142/s108842461950007x.

Full text

Abstract:

The reactivity of two phenolic porphyrins bearing respectively catechol and gallol-derived meso substituents (5,10,15,20-tetrakis(3,4-dihydroxyphenyl)porphyrin and 5,10,15,20-tetrakis(3,4,5-trihydroxyphenyl)porphyrin) with trivalent metallic ions (Fe, Mn, In) was studied. Six supramolecular compounds were obtained and structurally characterized by single crystal X-ray diffraction. In each compound, the supramolecular assembly was based on the axial coordination of a phenolate function to the metallic ion lying in the porphyrinic core. A great diversity of supramolecular architectures was accessible through such simple arrangements, and objects ranging from dimers to one-dimensional polymers were isolated. Some of these assemblies were further investigated in solution by mass spectrometry and by UV-vis absorption spectroscopy. For the iron-based materials, the redox behavior was studied in solution through cyclic voltammetry experiments in inert conditions and under air.

APA, Harvard, Vancouver, ISO, and other styles

9

BREGADZE, VLADIMIR I., IGOR B. SIVAEV, DETLEF GABEL, and DIETER WÖHRLE. "Polyhedral boron derivatives of porphyrins and phthalocyanines." Journal of Porphyrins and Phthalocyanines 05, no. 11 (November 2001): 767–81. http://dx.doi.org/10.1002/jpp.544.

Full text

Abstract:

The synthesis of compounds containing polyhedral boron cages and porphyrin or phthalocyanine units connected covalently in one molecule is reviewed. The importance of these compounds arises, on the one hand, from the use of polyhedral boron derivatives in neutron capture therapy for cancer; on the other hand, porphyrins and phthalocyanines are known as photosensitizers in photodynamic tumor therapy. Current interest in the binding of polyhedral boron compounds to porphyrins and phthalocyanines is due to the observation that porphyrins and phthalocyanines show improved uptake and good persistence in tissues. Medical applications of compounds containing polyhedral boron cages and porphyrin or phthalocyanine units in one molecule are briefly discussed.

APA, Harvard, Vancouver, ISO, and other styles

10

Kingsbury, Christopher J., Keith J. Flanagan, Hans-Georg Eckhardt, Marc Kielmann, and Mathias O. Senge. "Weak Interactions and Conformational Changes in Core-Protonated A2- and Ax-Type Porphyrin Dications." Molecules 25, no. 14 (July 13, 2020): 3195. http://dx.doi.org/10.3390/molecules25143195.

Full text

Abstract:

Individual chemical motifs are known to introduce structural distortions to the porphyrin macrocycle, be it in the core or at the periphery of the macrocycle. The interplay when introducing two or more of these known structural motifs has been scarcely explored and is not necessarily simply additive; these structural distortions have a chance to compound or negate to introduce new structural types. To this end, a series of compounds with complementary peripheral (5,15-disubstitution) and core (acidification) substitution patterns were investigated. The single-crystal X-ray structures of 18 5,15-diphenylporphyrin, 5,15-diphenylporphyrindi-ium diacid, and related compounds are reported, including the first example of a 5,15-dialkylporphyrindi-ium. Normal-coordinate structural decomposition (NSD) analysis is used for a detailed analysis of the conformation of the porphyrin subunit within the crystal structures. An elongation of porphyrin macrocycles along the C5,C15- axis (B2g symmetry) is observed in all of the free base porphyrins and porphyrin dications; distance across the core is around 0.3 Å in the free base and diacid compounds, and more than doubled in 5,15-dipentylporphyrin and 5,15-dipentylporphyrindi-ium diacid. While the free base porphyrins are largely planar, a large out-of-plane distortion can be observed in 5,15-diphenylporphyrin diacids, with the expected “projective saddle” shape characteristic for such systems. The combination of these two distortions (B2u and B2g) from regular porphyrin structure results in a macrocycle best characterized in the chiral point-group D2. A rare structural type of a cis-hydrogen bond chelate is observed for 5,15-dipentylporphyrindi-ium diacid, which adopts an achiral C2v symmetry. Crystallographic data indicate that the protonated porphyrin core forms hydrogen bonding chelates (N-H⋯X⋯H-N) to counter-anions. Weaker interactions, such as induced intramolecular C-H⋯O interactions from the porphyrin periphery are described, with distances characteristic of charge-assisted interactions. This paper offers a conceptual framework for accessing porphyrin macrocycles with designable distortion and symmetry, useful for the selective perturbation of electronic states and a design-for-application approach to solid state porphyrin materials.

APA, Harvard, Vancouver, ISO, and other styles

11

Zhdanova, Kseniya A., Inga O. Savelyeva, Artem V. Ezhov, Andrey P. Zhdanov, Konstantin Yu Zhizhin, Andrey F. Mironov, Natal’ya A. Bragina, et al. "Novel Cationic Meso-Arylporphyrins and Their Antiviral Activity against HSV-1." Pharmaceuticals 14, no. 3 (March 8, 2021): 242. http://dx.doi.org/10.3390/ph14030242.

Full text

Abstract:

This work is devoted to the search for new antiherpes simplex virus type 1 (HSV-1) drugs among synthetic tetrapyrroles and to an investigation of their antiviral properties under nonphotodynamic conditions. In this study, novel amphiphilic 5,10,15,20-tetrakis(4-(3-pyridyl-n-propanoyl)oxyphenyl)porphyrin tetrabromide (3a), 5,10,15,20-tetrakis(4-(6-pyridyl-n-hexanoyl)oxyphenyl)porphyrin tetrabromide (3b) and known 5,10,15,20-tetrakis(1-methyl-4-pyridinio)porphyrin tetraiodide (TMePyP) were synthesized, and their dark antiviral activity in vitro against HSV-1 was studied. The influence of porphyrin’s nanosized delivery vehicles based on Pluronic F127 on anti-HSV-1 activity was estimated. All the received compounds 3a, 3b and TMePyP showed virucidal efficiency and had an effect on viral replication stages. The new compound 3b showed the highest antiviral activity, close to 100%, with the lowest concentration, while the maximum TMePyP activity was observed with a high concentration; porphyrin 3a was the least active. The inclusion of the synthesized compounds in Pluronic F-127 polymeric micelles had a noticeable effect on antiviral activity only at higher porphyrin concentrations. Action of the received compounds differs by influence on the early or later reproduction stages. While 3a and TMePyP acted on all stages of the viral replication cycle, porphyrin 3b inhibited viral replication during the early stages of infection. The resulting compounds are promising for the development of utilitarian antiviral agents and, possibly, medical antiviral drugs.

APA, Harvard, Vancouver, ISO, and other styles

12

Sooambar, Chloé, Vincent Troiani, Hongjin Qiu, Sunichi Fukuzumi, Lucia Flamigni, Régis Rein, and Nathalie Solladié. "Chirality and spatially pre-organized multi-porphyrinoids." Journal of Porphyrins and Phthalocyanines 22, no. 04 (April 2018): 291–302. http://dx.doi.org/10.1142/s1088424618500396.

Full text

Abstract:

We report herein that chiral and enantiopure compounds such nucleosides and peptides can pre-organize multi-porphyrinic systems and influence their properties. The first example given concerns star-shaped mutli-porphyrins with chiral and enantiopure nucleosidic linkers. If the configuration is indeed a star-shaped nanomolecule, it appears that the induced conformation is nothing as expected. The four peripheral Zn(II) porphyrins collapse over the free-base central one, inducing totally different photo-physical properties. Despite a minor expected light energy harvesting behavior, the principal capability of this system is to quench the collected light energy and convert it from radiative to non-radiative de-activation. The second example concerns polypeptides with pendant porphyrins. The peptidic backbone confers to the systems, after a certain degree of oligomerization, a 3[Formula: see text] right handed helical conformation which induces cavities within the multi-porphyrinc architecture, ready to welcome guests and render, for example, the complexation of C[Formula: see text] much easier. We thus have constructed novel organic photovoltaic systems using supramolecular complexes of porphyrin–peptide oligomers with fullerene clusters. The composite cluster OTE/SnO[Formula: see text] electrode prepared with (P(ZnP)[Formula: see text] C[Formula: see text], exhibits an impressive incident photon-to-photocurrent efficiency (IPCE) with values reaching as high as 56%. The power conversion efficiency of the (P(H[Formula: see text]P)[Formula: see text] C[Formula: see text] modified electrode reaches 1.6%, which is 40 times higher than the value (0.043%) of the porphyrin monomer (P(H[Formula: see text]P)[Formula: see text] [Formula: see text] C[Formula: see text] modified electrode. Thus, the organization approach between porphyrins and fullerenes with polypeptide structures is promising, and may make it possible to further improve the light energy conversion properties by using a larger number of porphyrins in a polypeptide unit.

APA, Harvard, Vancouver, ISO, and other styles

13

Ol’shevskaya, Valentina A., Viktoriya M. Alpatova, Nadejda V. Konovalova, Elena G. Kononova, Evgeny G. Rys, and Natalya A. Bragina. "Fluorinated derivatives of meso-(aminophenyl)porphyrins: Synthesis and some transformation." Journal of Porphyrins and Phthalocyanines 22, no. 11 (October 18, 2018): 989–96. http://dx.doi.org/10.1142/s1088424618500967.

Full text

Abstract:

Condensation of amino groups in 5-(4-aminophenyl)-10,15,20-triphenylporphyrin and 5,10,15,20-tetrakis(4-aminophenyl)porphyrin with pentafluorobenzaldehyde resulted in corresponding Schiff bases and was shown to be a convenient route for the preparation of fluorinated porphyrin derivatives. Compounds thus obtained were easily transformed into the corresponding amines using sodium borohydride. Fluorinated carboranyl porphyrins were prepared via the nucleophilic substitution of the para-fluorine atom of pentafluorophenyl-substituted amine porphyrin derivatives with carborane S-nucleophiles. The alternative synthetic route to the fluorinated carboranyl porphyrins included the condensation of para-carboranyl-substituted tetrafluorobenzaldehyde with corresponding meso-aminoporphyrins. All prepared porphyrins were characterized by different spectroscopic techniques such as UV-vis, IR, 1H, 11B, 19F NMR and mass spectra.

APA, Harvard, Vancouver, ISO, and other styles

14

Tutel, Yusuf, Gökhan Sevinç, Betül Küçüköz, Elif Akhuseyin Yildiz, Ahmet Karatay, Fatih Mehmet Dumanoğulları, Halil Yılmaz, Mustafa Hayvali, and Ayhan Elmali. "Ultrafast Electron/Energy Transfer and Intersystem Crossing Mechanisms in BODIPY-Porphyrin Compounds." Processes 9, no. 2 (February 8, 2021): 312. http://dx.doi.org/10.3390/pr9020312.

Full text

Abstract:

Meso-substituted borondipyrromethene (BODIPY)-porphyrin compounds that include free base porphyrin with two different numbers of BODIPY groups (BDP-TTP and 3BDP-TTP) were designed and synthesized to analyze intramolecular energy transfer mechanisms of meso-substituted BODIPY-porphyrin dyads and the effect of the different numbers of BODIPY groups connected to free-base porphyrin on the energy transfer mechanism. Absorption spectra of BODIPY-porphyrin conjugates showed wide absorption features in the visible region, and that is highly valuable to increase light-harvesting efficiency. Fluorescence spectra of the studied compounds proved that BODIPY emission intensity decreased upon the photoexcitation of the BODIPY core, due to the energy transfer from BODIPY unit to porphyrin. In addition, ultrafast pump-probe spectroscopy measurements indicated that the energy transfer of the 3BDP-TTP compound (about 3 ps) is faster than the BDP-TTP compound (about 22 ps). Since the BODIPY core directly binds to the porphyrin unit, rapid energy transfer was seen for both compounds. Thus, the energy transfer rate increased with an increasing number of BODIPY moiety connected to free-base porphyrin.

APA, Harvard, Vancouver, ISO, and other styles

15

Ariga, Katsuhiko, Jonathan P. Hill, Yutaka Wakayama, Misaho Akada, Esther Barrena, and Dimas G. de Oteyza. "New aspects of porphyrins and related compounds: self-assembled structures in two-dimensional molecular arrays." Journal of Porphyrins and Phthalocyanines 13, no. 01 (January 2009): 22–34. http://dx.doi.org/10.1142/s1088424609000061.

Full text

Abstract:

The advanced state of development of molecular design and synthetic chemistry of porphyrins and related molecules makes these compounds good candidates for technological appli cations, in which well characterized and designed structures and properties are required. In particular, 2-dimensional molecular level control of porphyrin array structures should reveal new aspects of nanotechnology. In this review, recent research on porphyrin assemblies, including 2-dimensional porphyrin arrays, is described with emphasis on phenol- and quinone-substituted tetrapyrrole units. A series of research aimed at developing strategies for preparation of porphyrin molecular arrays, where several novel aspects of molecular arrays, including phase transitions, ordered 2-D phase boundaries, and hydrogen-bonding networks, are introduced.

APA, Harvard, Vancouver, ISO, and other styles

16

Genady, Afaf R., and Detlef Gabel. "Synthesis and optical properties of novel covalent and non-covalent porphyrin dimers." Journal of Porphyrins and Phthalocyanines 06, no. 06 (June 2002): 382–88. http://dx.doi.org/10.1142/s1088424602000476.

Full text

Abstract:

A new series of porphyrin dimers in different geometry have been synthesized. The reductive amination of dicarbonyl compounds, especially 2,5-hexadione and isophthaldhyde, with porphyrin monomers, α,α,α,α-5-(p-aminophenyl)-10,15,20-tris-(4-tolyl)porphyrin, α,α,α,α- and α,α,β,β-5,10,15,20-tetrakis-(o-aminophenyl)porphyrin in the presence of excess of NaBH 3 CN , afforded novel dimeric single and double bridged dimers of free base porphyrins, covalently linked through aliphatic or aromatic spacers. All the synthesized compounds were characterized by NMR, IR, UV-vis, and MS spectroscopy. Significant spectral changes occurred in the absorption spectra of these covalent porphyrin dimers comparing with that of the reference monomers, indicating strong electronic interaction between the adjacent porphyrin units. The UV-vis spectra showed the presence of another kind of non-covalent aggregation, which was observed at pH = 2.5-3 for some of these synthesized dimers. A similar behavior of association was also detected when α,β,α,β-5,10,15,20-tetrakis-(o-aminophenyl)porphyrin was measured at pH = 3.5 in acetone.

APA, Harvard, Vancouver, ISO, and other styles

17

Beyler, Maryline, Valérie Heitz, Julien Taesch, and Jean-Pierre Sauvage. "Templated synthesis of catenanes incorporating Zn(II) or Rh(III)-complexed porphyrins: the coordination chemistry-only approach." Journal of Porphyrins and Phthalocyanines 15, no. 09n10 (September 2011): 848–57. http://dx.doi.org/10.1142/s1088424611004002.

Full text

Abstract:

Porphyrin-containing [2]catenanes were obtained from relatively simple organic precursors thanks to "coordination chemistry-only". When the central porphyrin metal is Zn2+ the [2]catenanes were assembled in two steps by using Cu(I)–N interactions to assemble acyclic complexes and Zn(II)–N interactions to generate rings. These sophisticated architectures were obtained in excellent yield since the formation of the thermodynamic products is favored over that of kinetic products. This also explains why a perfect fit in terms of distances and angles between the components to assemble leads to highly stable coordination chemistry-assembled species. When a second row metal with an inert coordination sphere, like Rh(III) was chosen as metal centre of the porphyrins, direct metalation of porphyrinic compounds with [Rh(CO)2Cl]2 was not met with success when the bidentate chelate used as connector was metal free. A three-step strategy was used for the synthesis of a tetra-rhodiumporphyrin[2]-catenane: (i) copper(I)-driven entwining of two free-base porphyrin-bearing bidentate chelates followed (ii) by insertion of rhodium in the porphyrin nuclei and finally (iii) cyclisation via formation of N-Rh coordination bonds.

APA, Harvard, Vancouver, ISO, and other styles

18

Walaszek, Dominika J., Ksenia Maximova, Katarzyna Rybicka-Jasińska, Agnieszka Lipke, and Dorota Gryko. "Synthesis of chiral porphyrins and their use in photochemical oxidation of carbonyl compounds." Journal of Porphyrins and Phthalocyanines 18, no. 06 (June 2014): 493–505. http://dx.doi.org/10.1142/s1088424614500229.

Full text

Abstract:

A series of chiral A4, A2B2, and AB3 porphyrins bearing proline moieties at the meso-phenyl group has been synthesized. Photostability studies revealed that the number of L-proline units and their position on meso-phenyl rings strongly influence the decomposition rate of the catalyst. 5,10,15-Tris(mesityl)-20-(3-prolinanilidylphenyl)-21,23H-porphyrin is the most stable while porphyrin bearing four 3-prolinanilidylphenyl substituents completely decomposes in CHCl 3 within 3 h. Singlet oxygen quantum yields of the conjugates were determined by measuring the peak areas of the NIR emission of 1 O 2 (1280 nm) generated by these compounds and compared to that generated by the reference standard TPP. Selected porphyrins were tested as catalysts in the photooxidation of carbonyl compounds at the α-position.

APA, Harvard, Vancouver, ISO, and other styles

19

Razavi, Hossein, Ezzedin Mohajerani, Naser Safari, Hashem Shahroosvand, and Amir Khabbazi. "Electroluminescence and photoluminescence in porphyrin derived compounds in a new polymeric PVK:PBD host." Journal of Porphyrins and Phthalocyanines 16, no. 04 (April 2012): 396–402. http://dx.doi.org/10.1142/s1088424612500642.

Full text

Abstract:

The electroluminescence (EL) and photoluminescence (PL) of five porphyrin compounds have been investigated. Each of the porphyrin derivations were doped with different concentrations in a PVK(polyvinyl carbazole):PBD(2-(4-biphenyl)-5-(4-t-butyl-phenyl)-1,3,4-oxadiazole) blend as the host. The effect of the porphyrin type on the variation of the peak wavelength, FWHM (wavelength peak of emission spectra), CIE (1931 color Space standard) Coordinate, I–V characteristics have been studied in the same host, and the PL and EL spectra for all porphyrins were compared. It has been shown that the electrical and optical properties of the fabricated device can be controlled by altering the structure and concentration of the dopant.

APA, Harvard, Vancouver, ISO, and other styles

20

Kulikov, Oleg V., Izabela Schmidt, Ana Z. Muresan, Marcia A. P. Lee, David F. Bocian, and Jonathan S. Lindsey. "Synthesis of porphyrins for metal deposition studies in molecular information storage applications." Journal of Porphyrins and Phthalocyanines 11, no. 10 (October 2007): 699–712. http://dx.doi.org/10.1142/s1088424607000801.

Full text

Abstract:

Porphyrins may serve as the active charge-storage medium in memory chips. A series of 14 porphyrins (trans-A2B2, trans-AB2C, or A4 type; free base, copper or zinc chelate) has been synthesized for investigation of metal deposition on porphyrin monolayers. Each trans-AB2C porphyrin is equipped with a surface attachment group and a distal functional group (or flanking functional groups). The surface attachment groups include S-acetylthiomethyl, hydroxymethyl, TMS-ethynyl, allyl, and triallylmethyl; the functional groups include amino, cyano, dipyrrin-5-yl, formyl, and nitro; all of which are attached to the p-position of a porphyrin meso-phenyl group. Two non-redox-active triallylmethyl-substituted arenes were also prepared for use as control compounds.

APA, Harvard, Vancouver, ISO, and other styles

21

Zhu, Pei Hua, Cheng Zhu, Yang Fang Zhao, Qin Wei, and Yan Li Chen. "Switching Porphyrin Fluorescence on and off through Redox." Advanced Materials Research 79-82 (August 2009): 1703–6. http://dx.doi.org/10.4028/www.scientific.net/amr.79-82.1703.

Full text

Abstract:

Three new zinc porphyrins ( [5,15-bisferrocenyl-porphyrinato]-zinc(II)(4), [5,15-bisferrocenyl-10,20-bis(4-nitro-phenyl)-porphyrinato]-zinc(II)(5), and [5,10,15,20- tetraferrocenyl-porphyrinato]-zinc(II) (6)) with ferrocenyl units at the meso-positions of porphyrin ring have been prepared and characterized. Towards further understanding the fluorescence quenching and recovery of ferrocene-porphyrins, the fluorescence spectra of these compounds was detailedly studied.

APA, Harvard, Vancouver, ISO, and other styles

22

Chambron, Jean-Claude, Jean-Paul Collin, Isabelle Dixon, Valérie Heitz, Xavier J. Salom-Roig, and Jean-Pierre Sauvage. "Synthesis of one-dimensional bis-porphyrinic compounds with a transition metal complex as bridging unit." Journal of Porphyrins and Phthalocyanines 08, no. 01 (January 2004): 82–92. http://dx.doi.org/10.1142/s1088424604000076.

Full text

Abstract:

Linear multicomponent systems, consisting of two porphyrins attached to a central transition metal center, have been prepared and some of their electron- or energy transfer properties have been studied. Each porphyrin is covalently bound to a bidentate or a terdentate ligand, these coordinating molecules being gathered around the metal to afford the desired structure. The spatial arrangement is such that the porphyrinic components are located at both ends of an axis, the transition metal occupying its center. The edge-to-edge distance between the porphyrins is relatively large (~ 20 to 25 Å) and, due to the rigidity of the connectors, it is very well controlled. Three different strategies have been used to construct such assemblies. In the first approach, the porphyrinic fragments are attached at the back of 2,2′,6′,2″-terpyridine ligands (terpy), on the central position (4′). After reaction with an appropriate metal center (ruthenium(II) or iridium(III)), an octahedral complex is obtained which constitutes the central part of the assembly, whereas the porphyrins are at the periphery of the central complex. The second strategy involves the preparation of a 5,5′-disubstituted 2,2′-bipyridine (bipy) ligand followed by its coordination to ruthenium(II). Subsequently, the porphyrinic nuclei are constructed at both ends of the substituents, leading to a linear geometry with a central complex and two laterally-disposed porphyrins. Finally, a very special ligand has been designed and synthesized, which incorporates two 1,10-phenanthroline nuclei (phen). This ligand can wrap itself around an octahedral center (ruthenium(II)) so as to generate a helical arrangement. Both ends of the single-stranded helix can subsequently be attached to porphyrins.

APA, Harvard, Vancouver, ISO, and other styles

23

Maqueira, Luis, Aristides C. Valdés, Augusto Iribarren, and Celso P. de Melo. "Preparation and characterization of hydrophobic porphyrin nanoaggregates dispersed in polyvinyl alcohol films." Journal of Porphyrins and Phthalocyanines 17, no. 04 (April 2013): 283–88. http://dx.doi.org/10.1142/s1088424613500028.

Full text

Abstract:

It is known that among other applications porphyrin aggregates can be used in the detection of volatile organic compounds (VOC) and gases and vapors in general. However, the use of porphyrins for this purpose has been limited by the fact that usually the porphyrin and the polymer employed as a matrix are soluble in different media, such as polyvinyl alcohol and tetraphenylporphyrin, respectively. In this paper, we discuss how starting from stable aqueous solutions of hydrophobic porphyrins one can use the drop coating method to prepare polyvinyl alcohol polymer matrices containing porphyrin aggregates. The resulting solid films were characterized by optical techniques, and we have used UV-vis absorption spectroscopy to analyze how they interact with vapors of HCl , NO2 and NH3 .

APA, Harvard, Vancouver, ISO, and other styles

24

Habib, Md Ahsan, Ashish Kumar Sarker, and Masaaki Tabata. "Interactions of DNA with H2TMPyP4+and Ru(II)TMPyP4+: Probable Lead Compounds for African Sleeping Sickness." Bangladesh Pharmaceutical Journal 17, no. 1 (February 21, 2015): 79–85. http://dx.doi.org/10.3329/bpj.v17i1.22321.

Full text

Abstract:

Interactions of DNA with free base porphyrin, tetrakis(1-methylpyridium-4-yl)porphyrin (H2TMPyP4+) and its metallo-derivative of ruthenium(II) have been investigated by UV-Vis, fluorescence and circular dichroism (CD) spectroscopy at 0.1 M NaCl, 7.5 pH and 25 °C. The results suggest that Ru(II)TMPyP4+ interacts with DNA via outside binding in self-stacking manner as indicated by UV-Vis data, a small red shift (?? =3 nm) and a minimal hypochromicity (10%) upon addition of DNA. CD spectra showed the presence of a new peak in the Soret region on addition of Ru(II)TMPyP4+ to DNA solution. On the other hand, the interaction of free base porphyrin, H2TMPyP4+ with DNA revealed a significant hypochromicity (30%) and a large red shift (??=20 nm)in the UV-Vis results which conforms intercalation of free base porphyrin with DNA. In this case, the CD results showed only a negative peak developed in the Soret region during titration with DNA. Fluorescence spectroscopy revealed that initially aggregated porphyrin species were de-aggregated after addition of DNA. This phenomenon has been verified with the fluorescence experiments for the porphyrins in the presence of different concentrations of NaCl and ethanol. Ru(II)TMPyP4+ showed enhanced DNA cleavage in the presence of EcoR1 restriction enzyme, where the enzyme did not cleave DNA. Metallo-porphyrins having the ability to cleave DNA could be used as chemotherapeutic agents for the treatment of African sleeping sickness (Trypanosomiasis). DOI: http://dx.doi.org/10.3329/bpj.v17i1.22321 Bangladesh Pharmaceutical Journal 17(1): 79-85, 2014

APA, Harvard, Vancouver, ISO, and other styles

25

Liang, Min, Yuanyuan Li, Mingbo Zhou, Yutao Rao, Bangshao Yin, Ling Xu, Tingting Gu, et al. "Synthesis and characterization of porphyrin–pyrene hybrids." Journal of Porphyrins and Phthalocyanines 24, no. 01n03 (January 2020): 278–85. http://dx.doi.org/10.1142/s1088424619501025.

Full text

Abstract:

Palladium-catalyzed Suzuki–Miyaura coupling of 5-functionalized Ni(II) porphyrins with 1,3,6,8-tetrafunctionalizedpyrenes was carried out to obtain two kinds of porphyrin–pyrene hybrids. These compounds were comprehensively characterized by nuclear magnetic resonance (NMR), high-resolution mass spectrometry and ultraviolet-visible (UV-vis) absorption spectrometry, and their electrochemical properties were studied by both cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Fluorescence spectra for zinc compounds and free-base compounds were performed. In addition, the structure of 4Zn, a porphyrin tetramer, was determined by X-ray diffraction analysis, in which two planes formed by the porphyrin unit and the pyrene moiety adopt nearly perpendicular geometry with two sets of dihedral angles displaying 85.14 (4)[Formula: see text] and 83.90 (4)[Formula: see text], respectively. In the UV-vis absorption spectra, the maximum wavelengths of Soret bands and Q bands for these hybrids were observed at 434 and 648 nm. As the number of porphyrin units increases, the corresponding molar extinction coefficient rises markedly, in which the maximal value is 7.4 × 105 M[Formula: see text] • cm[Formula: see text] belonging to 4Zn. Moreover, the presence of energy transformation from the pyrene moiety to the porphyrin unit has been proved by emission spectra. Finally, the electrochemical properties of these porphyrin–pyrene hybrids were analyzed by using cyclic voltammetry and differential pulse voltammetry, which show that the nickel hybrids possessed the maximal electrochemical highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap and the zinc compounds displayed the minimum electrochemical HOMO–LUMO gap.

APA, Harvard, Vancouver, ISO, and other styles

26

Dekkiche, Hervé, Yoshihiro Kikkawa, Lydia Karmazin, Christophe Jeandon, and Romain Ruppert. "Synthesis of porphyrins bearing alkynyl- or arylalkynyl-meso-groups." Journal of Porphyrins and Phthalocyanines 20, no. 01n04 (January 2016): 292–301. http://dx.doi.org/10.1142/s108842461650005x.

Full text

Abstract:

The synthesis of new porphyrins bearing external coordination sites and long alkyl chains is described. In particular, the possibility to use the Sonogashira coupling to introduce long alkynyl chains and the synthetic pathway to obtain these compounds is detailed. Two crystal structures of these new porphyrin derivatives were obtained. The synthesis of porphyrin dimers linked by a palladium(II) ion is also reported and some electronic consequences presented.

APA, Harvard, Vancouver, ISO, and other styles

27

Ojaimi, Maya El, Benoit Habermeyer, Claude P. Gros, and Jean-Michel Barbe. "Towards the synthesis of substituted porphyrins by a pyridyl group bearing a reactive functionality." Journal of Porphyrins and Phthalocyanines 14, no. 06 (June 2010): 469–80. http://dx.doi.org/10.1142/s108842461000232x.

Full text

Abstract:

Pyridyl-substituted porphyrins bearing a reactive functionality were prepared via Suzuki cross-coupling reactions and resulted in very good yields. These compounds are precursors of new porphyrin architectures able to coordinate two metals: one in the porphyrin core and the second around the pyridyl moiety. During the coupling reactions, a higher reactivity of a chloro picolyl group was evidenced compared to a bromo function on the same reacting molecule.

APA, Harvard, Vancouver, ISO, and other styles

28

Heffron, Joe, Matthew Bork, Brooke K. Mayer, and Troy Skwor. "A Comparison of Porphyrin Photosensitizers in Photodynamic Inactivation of RNA and DNA Bacteriophages." Viruses 13, no. 3 (March 23, 2021): 530. http://dx.doi.org/10.3390/v13030530.

Full text

Abstract:

Effective broad-spectrum antiviral treatments are in dire need as disinfectants and therapeutic alternatives. One such method of disinfection is photodynamic inactivation, which involves the production of reactive oxygen species from dissolved oxygen in response to light-stimulated photosensitizers. This study evaluated the efficacy of functionalized porphyrin compounds for photodynamic inactivation of bacteriophages as human virus surrogates. A blue-light light emitting diode (LED) lamp was used to activate porphyrin compounds in aqueous solution (phosphate buffer). The DNA bacteriophages ΦX174 and P22 were more resistant to porphyrin TMPyP photodynamic inactivation than RNA bacteriophage fr, with increasing rates of inactivation in the order: ΦX174 << P22 << fr. Bacteriophage ΦX174 was therefore considered a resistant virus suitable for the evaluation of three additional porphyrins. These porphyrins were synthesized from TMPyP by inclusion of a central palladium ion (PdT4) and/or the addition of a hydrophobic C14 chain (PdC14 or C14). While the inactivation rate of bacteriophage ΦX174 via TMPyP was similar to previous reports of resistant viruses, ΦX174 inactivation increased by a factor of approximately 2.5 using the metalloporphyrins PdT4 and PdC14. The order of porphyrin effectiveness was TMPyP < C14 < PdT4 < PdC14, indicating that both Pd2+ ligation and C14 functionalization aided virus inactivation.

APA, Harvard, Vancouver, ISO, and other styles

29

FENYO, DAVID, BRIAN T. CHAIT, THOMAS E. JOHNSON, and JONATHAN S. LINDSEY. "Laser Desorption Mass Spectrometry of Synthetic Multiporphyrin Arrays." Journal of Porphyrins and Phthalocyanines 01, no. 01 (January 1997): 93–99. http://dx.doi.org/10.1002/(sici)1099-1409(199701)1:1<93::aid-jpp11>3.0.co;2-x.

Full text

Abstract:

Laser desorption mass spectrometry and matrix-assisted laser desorption mass spectrometry (MALDI-MS) have been investigated for the analysis of a set of synthetic compounds containing one, two, five, eight or nine porphyrins. Intact singly ionized molecule ions were observed for each compound and the spectra were readily interpretable. The use of a matrix of 4-hydroxy-α-cyano-cinnamic acid greatly diminished the extent of fragmentation. Examination of the resulting mass spectra provides insight into aspects of the MALDI process. The present results show that high molecular weight photochemically active materials that absorb strongly at the wavelength of laser illumination can be analysed effectively and that MALDI-MS is a powerful analytical tool for synthetic chemistry of porphyrin-based molecules with dimensions ranging to 10 nm. The strong molecule ions observed for the largest compounds investigated ( Zn 8-octamer, Zn 9-nonamer) indicates that this method should be applicable to even larger porphyrin arrays.

APA, Harvard, Vancouver, ISO, and other styles

30

Michalak, Julien, Kiril P. Birin, Sankar Muniappan, Elena Ranyuk, Yulia Yu Enakieva, Yulia G. Gorbunova, Christine Stern, Alla Bessmertnykh-Lemeune, and Roger Guilard. "Synthesis of porphyrin-bis(polyazamacrocycle) triads via Suzuki coupling reaction." Journal of Porphyrins and Phthalocyanines 18, no. 01n02 (January 2014): 35–48. http://dx.doi.org/10.1142/s1088424614500084.

Full text

Abstract:

Suzuki–Miyaura cross-coupling reaction has been used for the synthesis of tricyclic architectures based on trans-A2B2-porphyrins and bisaminal-protected polyazamacrocycles which are linked directly or by a p-phenylene spacer. This modular approach allowed the synthesis of ligands with various substituted porphyrin macrocycles and bisaminal-protected tetraazamacrocycles possessing different cavity sizes. These molecules can be assembled into dimers using a DABCO linker. Deprotection of these compounds afforded porphyrin-bis(polyazamacrocycle) triads.

APA, Harvard, Vancouver, ISO, and other styles

31

Gajewski, Mariusz, and Leszek Czuchajowski. "Phosphorus (V) porphyrin diaxially substituted with Leu-enkephalin." Open Chemistry 2, no. 3 (September 1, 2004): 446–55. http://dx.doi.org/10.2478/bf02476200.

Full text

Abstract:

AbstractSynthesis of the first phosphorus (V) porphyrin-peptide conjugate was successfully accomplished. A biologically active peptide, leucine enkephalin, was constructed on the phosphorus atom of the 5,10,15,20-meso-tetraphenylporphinato dichlorophosphorus (V) chloride. The method involved solution phase peptide synthesis. The first C-terminal amino acid in the sequence of the peptide was axially attached to the porphyrin through a linker, 3-aminopropanol, and the remainder of leucine enkephalin was synthesized by subsequent additions of amino acids. Leucine enkephalin-P(V) porphyrin conjugate represents a new group of compounds, and its synthesis broadens potential applications of P(V) porphyrine, e.g. in photodynamic therapy.

APA, Harvard, Vancouver, ISO, and other styles

32

Kingsbury, Christopher J., Keith J. Flanagan, Marc Kielmann, Brendan Twamley, and Mathias O. Senge. "Crystal structures of 2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetrakis(pentafluorophenyl)porphyrin as the chloroform monosolvate and tetrahydrofuran monosolvate." Acta Crystallographica Section E Crystallographic Communications 76, no. 2 (January 17, 2020): 214–20. http://dx.doi.org/10.1107/s2056989020000432.

Full text

Abstract:

The crystal structures of the title compounds, two solvates (CHCl3 and THF) of a symmetric and highly substituted porphyrin, C44H2Br8F20N4 or OBrTPFPP, are described. These structures each feature a non-planar porphyrin ring, exhibiting a similar conformation of the strained ring independent of solvent identity. These distorted porphyrins are able to form hydrogen bonds and sub-van der Waals halogen interactions with enclathrated solvent; supramolecular interactions of proximal macrocycles are additionally affected by solvent choice. The crystal studied for compound 1·CHCl3 was refined as an inversion twin. One pentafluorophenyl group was modelled as disordered over two sites [occupancy ratio = 0.462 (7):0.538 (7)]. The chloroform solvate was also modelled as disordered over two orientations [occupancy ratio = 0.882 (7): 0.118 (7).

APA, Harvard, Vancouver, ISO, and other styles

33

Gangemi, Chiara M. A., Bruno D’Agostino, Rosalba Randazzo, Massimiliano Gaeta, Maria E. Fragalà, Roberto Purrello, and Alessandro D’Urso. "Interaction of spermine derivative porphyrin with DNA." Journal of Porphyrins and Phthalocyanines 22, no. 07 (July 2018): 581–87. http://dx.doi.org/10.1142/s1088424618500645.

Full text

Abstract:

Porphyrinoids are ideal compounds to be incorporated into DNA due to their peculiar spectroscopic characteristics, fascinating photochemistry and synthetic versatility. The ability to act as photosensitizers in the presence of oxygen promoted interest of the scientific community to study the non-covalent binding of porphyrins with DNA in order to use them in photodynamic therapy. Thus, the understanding of the mechanisms involved in the binding of porphyrins with DNA can help to find a porphyrin with specific base degradation activity. In this work we characterized the binding modes of spermine derivative porphyrin with three different polynucleotides: ct-DNA, poly(dG-dC)[Formula: see text] in both B- and Z-conformation using several spectroscopic techniques (UV-vis, Electronic Circular Dichroism and Resonance Light Scattering).

APA, Harvard, Vancouver, ISO, and other styles

34

Kang, Guo Jun, Chao Song, and Xue Feng Ren. "Effect of Meso-Submissions to Electronic Structure and Optical Properties of Ruffled Si Porphyrins Relatives." Advanced Materials Research 1028 (September 2014): 7–13. http://dx.doi.org/10.4028/www.scientific.net/amr.1028.7.

Full text

Abstract:

A series of silicon (VI) porphyrins compounds with varying meso substitutions Si (TPP)Cl2 (where X=5,10,15,20-tetraphenylporphyrin), Si (TFP)Cl2 (X=5,10,15,20-tetrafluorenylporphyrin), Si (TQP)Cl2(X=5‚10‚15‚20-tetra (2,3,6,7-tetrahydro-1H,5H-benzo [ij] puinolizine) porphyrin),Si (TMP)Cl2(X=5,10,15,20-tetra (N,N-dimethylphenyl) porphyrin) have been investigated using density functional theory (DFT) to assess the influence of ruffled conformation on the electronic structures, frontier molecular orbital, charge carrier transport, electronic spectra. The electronic structures reveal that all these Si porphyrins display visible ruffling distortion, as the dihedral angle Cα2-N2-N4-Cα4 are ca. 30 ̊. And calculations confirm that ruffed distortion result in higher LUMO energies, lower EA values than corresponding planed Zn porphyrins, especial for similar λhole and λelectron values. These calculations suggest that the ruffled conformation bring about better charge injection and transport, which would broaden the application of distorted porphyrin in several different fields.

APA, Harvard, Vancouver, ISO, and other styles

35

Gajewski, Mariusz P., and Leszek Czuchajowski. "p-nitrobenzamide substituted phosphorus(V) porphyrins: synthesis and interactions with DNA." Journal of Porphyrins and Phthalocyanines 09, no. 07 (July 2005): 453–62. http://dx.doi.org/10.1142/s1088424605000563.

Full text

Abstract:

Four new phosphorus(V) porphyrins were designed and synthesized. The compounds were diaxially substituted with 4-nitrobenzamide. The axial ligands were attached to the P(V) center of the porphyrins through methylene linkers of different lengths. DNA titrations showed the expected porphyrin binding. When exposed to 532 nm laser light, which corresponds to the porphyrin Q band, the photosensitizers induced DNA nicking. Inhibition of the nicking by sodium azide suggested participation of singlet oxygen in the process. Photoexcitation with 305 nm laser light, which corresponds to absorption of 4-nitrobenzamide, also resulted in DNA damage. Due to the lack of electronic communication between the axial ligands and the porphyrin, the desired pathway of DNA cleavage was chosen by selecting a proper wavelength of the light used for photoexcitation. The activities of the porphyrins in photoinduced DNA nicking were very similar in both experiments: irradiation with 305 and 532 nm light, and were inversely correlated with the length of the linkers.

APA, Harvard, Vancouver, ISO, and other styles

36

Feng, Liang, Kun-Yu Wang, Elizabeth Joseph, and Hong-Cai Zhou. "Catalytic Porphyrin Framework Compounds." Trends in Chemistry 2, no. 6 (June 2020): 555–68. http://dx.doi.org/10.1016/j.trechm.2020.01.003.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Stout, Kathleen, Theo P. J. Peters, Mathijs F. J. Mabesoone, Fabian L. L. Visschers, Eline M. Meijer, Joëlle‐Rose Klop, Jeroen Berg, et al. "Double Porphyrin Cage Compounds." European Journal of Organic Chemistry 2020, no. 45 (November 16, 2020): 7087–100. http://dx.doi.org/10.1002/ejoc.202001211.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Mercorillo, Giuseppa, Roberta Puglisi, Emanuela Spina, and Daniele Vitalini. "Synthesis and characterization of new porphyrin/β-cyclodextrin derivatives covalently connected by aliphatic chains of different length." Journal of Porphyrins and Phthalocyanines 20, no. 06 (June 2016): 700–707. http://dx.doi.org/10.1142/s1088424616500644.

Full text

Abstract:

Covalently linked porphyrin/β-cyclodextrin derivatives have been synthesized by reaction between 5,10,15-tris-{p-[9-methoxy-tris-(ethyleneoxy)-phenyl]}-20-(p-hydroxyphenyl)-porphyrin, β-cyclodextrin-6-alcoholate and di-brominated aliphatic chains of different length, and characterized by MALDI-TOF mass spectrometry, 1H NMR and UV-vis spectroscopy. As a function of chain length, these compounds exhibit different degrees of water solubility, becoming higher with increasing chain length. The lack of self-assemblies between porphyrins and β-cyclodextrins (which renders the two sub-units completely free to perform their activities) and their water solubility, make these compounds excellent candidates in fields like drug-delivery or photodynamic therapy.

APA, Harvard, Vancouver, ISO, and other styles

39

Buczyńska, Joanna, Agnieszka Gajewska, Aleksander Gorski, Barbara Golec, Krzysztof Nawara, Renata Rybakiewicz, and Jacek Waluk. "Synthesis and Photostability of Cyclooctatetraene-Substituted Free Base Porphyrins." Chemistry 3, no. 1 (January 21, 2021): 104–15. http://dx.doi.org/10.3390/chemistry3010008.

Full text

Abstract:

A series of free base meso-tetraarylporphyrins functionalized with substituents containing one, two, and four cyclooctatetraene (COT) moieties have been obtained and characterized by spectral and photophysical studies. Three COT-free porphyrins served as reference compounds. COT is a triplet quencher, well-known to enhance the photostability of several, but not all, fluorophores. In the case of porphyrins, substitution with COT improves photostability in zinc derivatives, but for free bases, the effect is the opposite. We show that placing the COT moiety further from the free base porphyrin core enhances the photostability when the COT group lies in the direct vicinity of the macrocycle. The quantum yields of photobleaching inversely correlate with porphyrin oxidation potentials. An improvement in photostability in both COT-containing and COT-free porphyrins can be achieved by screening the porphyrin core from oxygen by switching from tolyl to mesityl substituents. This leads to a decrease in the photobleaching quantum yield, even though triplet lifetimes are longer. The results confirm the involvement of oxygen in the photodegradation of porphyrins.

APA, Harvard, Vancouver, ISO, and other styles

40

Kong, A., C. Mao, Y. Wang, Q. Lin, X. Bu, and P. Feng. "Hierarchically porous few-layer porphyrinic carbon nanosheets formed by a VOx-templating method for high-efficiency oxygen electroreduction." Journal of Materials Chemistry A 4, no. 19 (2016): 7305–12. http://dx.doi.org/10.1039/c6ta00154h.

Full text

Abstract:

Few-layer porous porphyrinic carbon nanosheets with highly efficient oxygen electroreduction performance were obtained by thermal conversion of Fe-porphyrin/V₂O₅ intercalation compounds.

APA, Harvard, Vancouver, ISO, and other styles

41

Sheng, Ning, Jing Sun, Yongzhong Bian, Jianzhuang Jiang, and Dong Xu. "Synthesis and third-order nonlinear optical properties of novel ethynyl-linked heteropentamer composed of four porphyrins and one pyrene." Journal of Porphyrins and Phthalocyanines 13, no. 02 (February 2009): 275–82. http://dx.doi.org/10.1142/s1088424609000346.

Full text

Abstract:

Novel heteropentameric porphyrins-pyrene arrays, in which four meso-tetraphenyl porphyrins are linked to the center unit of pyrene by four acetylenyl bonds, were designed and synthesized. The newly synthesized heteropentameric compounds have been characterized by a wide range of spectroscopic methods. The third-order nonlinear optical (NLO) properties of both the metal-free and zinc compounds of the three-dimensional arrays were investigated by Z-scan experiments, showing enhanced NLO properties compared with that of the porphyrin and pyrene monomers.

APA, Harvard, Vancouver, ISO, and other styles

42

AMAO, YUTAKA, TOSHIAKI KAMACHI, and ICHIRO OKURA. "Photoinduced Hydrogen Evolution with Hydrogenase and Water-soluble Viologen-linked Zinc Porphyrins." Journal of Porphyrins and Phthalocyanines 02, no. 03 (May 1998): 201–7. http://dx.doi.org/10.1002/(sici)1099-1409(199805/06)2:3<201::aid-jpp64>3.0.co;2-x.

Full text

Abstract:

A series of water-soluble viologen-linked zinc porphyrins with different methylene chain lengths (n = 3−6) between porphyrin and viologen, ZnP ( C n V )4, were synthesized and characterized. The intra- molecular electron transfer rate constants from the porphyrin moiety of ZnP (Cn V )4 to viologen were measured by using fluorescence lifetime and laser flash photolysis. Both the photoexcited singlet state and the triplet state of the porphyrin were quenched by the bonded viologen. These compounds were applied to photoinduced hydrogen evolution in the system containing nicotinamide-adenine dinucleotide phosphate (reduced form NADPH), ZnP ( C n V )4 and hydrogenase under steady-state irradiation.

APA, Harvard, Vancouver, ISO, and other styles

43

Xu, Weijie, Yuanyuan Fang, Zhongping Ou, Mingyuan Chen, and Karl M. Kadish. "Synthesis, electrochemical and spectroelectrochemical characterization of iron(III) tetraarylporphyrins containing four β,β′-butano and β,β′-benzo fused rings." Journal of Porphyrins and Phthalocyanines 22, no. 06 (June 2018): 521–34. http://dx.doi.org/10.1142/s1088424618500517.

Full text

Abstract:

Six iron(III) tetraarylporphyrins containing four [Formula: see text]-butano or [Formula: see text]-benzo fused rings were synthesized and characterized by electrochemistry and spectroelectrochemistry in nonaqueous media. The examined compounds are represented as butano(TpYPP)FeCl and benzo(TpYPP)FeCl, where TpYPP is a dianion of the meso-substituted porphyrin, Y is a CH[Formula: see text], H or Cl substituent on the para-position of the four meso-phenyl rings and butano and benzo are the [Formula: see text]-substituents on each of the four pyrrole rings of the compound. Up to three reductions are observed for each Fe(III) butano- and benzoporphyrin in CH[Formula: see text]Cl[Formula: see text] or pyridine containing 0.1 M TBAP, the first of which is assigned in each case to a metal-centered electron transfer. The second reduction is also metal-centered in CH[Formula: see text]Cl[Formula: see text] and leads to formation of an Fe(I) porphyrin, but it is porphyrin ring-centered and gives an Fe(II) porphyrin [Formula: see text]-anion radical reduction product when pyridine is used as the solvent. The effects of the solvent and type of fused ring system (butano or benzo) on the UV-vis spectra and electrochemical properties of the Fe(III) porphyrins are discussed and comparisons are made to both the structurally related non-[Formula: see text]-substituted iron porphyrins and earlier described butano- or benzotetraarylporphyrins containing Cu(II) or Co(II) central metal ions.

APA, Harvard, Vancouver, ISO, and other styles

44

Premovic, Pavle, Ivana Tonsa, Dragan Djordjevic, and Mirjana Pavlovic. "Air oxidation of the kerogen/asphaltene vanadyl porphyrins: An electron spin resonance study." Journal of the Serbian Chemical Society 65, no. 2 (2000): 113–21. http://dx.doi.org/10.2298/jsc0002113p.

Full text

Abstract:

The thermal behavior of vanadyl porphyrins was studied by electron spin resonance during heating of kerogens, isolated from the La Luna (Venezuela) and Serpiano (Switzerland) bituminous rocks, at 250?C for 1 to 20 days in the presence of air. During the thermal treatment of the kerogens, the vanadyl porphyrins resonance signals decrease monotonically and become quite small after 6 days of heating. Concomitantly, new vanadyl signals appear and, at longer heating times, dominate the spectrum. It is suggested that the secondary vanadyl species must have been formed from vanadyl porphyrins. Similar conversions of vanadyl porphyrins are observed under the same experimental conditions for asphaltenes extracted from the La Luna and Serpiano rocks, and floating asphalt from the Dead Sea (Israel). A comparison of the spin-Hamiltonian parameters for vanadyl porphyrins and the vanadyl compounds obtained during pyrolysis of the kerogens/asphaltenes suggests that the latter are of a non-porphyrin type. For comparison a study was conducted on Western Kentucky No. 9 coal enriched with vanadium (>400 ppm) from six mines. All the coal samples show only the presence of predominant by non-porphyrin vanadyl compounds, similar to those generated through laboratory heating of the kerogens/asphaltenes in air. In addition, some samples also contain a minor amount of vanadyl porphyrins.

APA, Harvard, Vancouver, ISO, and other styles

45

Caicedo, Carolina, Gerardo Zaragoza-Galán, Joaquim Crusats, Zoubir El-Hachemi, Ana Martínez, and Ernesto Rivera. "Design of novel luminescent porphyrins bearing donor–acceptor groups." Journal of Porphyrins and Phthalocyanines 18, no. 03 (March 2014): 209–20. http://dx.doi.org/10.1142/s1088424613501083.

Full text

Abstract:

In this work, we report the synthesis and characterization of a novel series of porphyrins, some of them bearing donor-acceptor groups. meso-substituted free-base porphyrins:5-(4-amino-phenyl)-10,15,20-triphenylporphyrin (TPPNH2) and 5-(4-acetamidophenyl)-10,15,20-triphenylporphyrin (TPPNHAc), as well as their tribromo (Br3TPPNH2 and Br3TPPNHAc) and trimethylsilyl-substituted homologs (TMS3TPPNH2 and TMS3TPPNHAc were synthesized and characterized. The optical properties of all compounds have been studied by absorption and fluorescence spectroscopy. Theoretical calculations were performed in order to recognize the optimized geometry and the correlation with the optical properties. On the other hand, an azobenzene containing porphyrin (TPPN2PhC14H29) was also prepared to study the influence of the trans-cis photoisomerization on its optical properties. Almost all porphyrin derivatives exhibited a Soret band at ca. λ = 419–422 nm followed by four Q-bands in the range between 500–700 nm. Besides, these porphyrins showed two emission bands located at ca. λ = 654 nm and 714 nm with different intensities, depending on the substituents. The relative quantum yields were calculated for these compounds with respect to the most emissive species.

APA, Harvard, Vancouver, ISO, and other styles

46

Hamer, Mariana, Rolando M. Caraballo, Peter J. Eaton, and Craig Medforth. "Nanoparticles as template for porphyrin nanostructure growth." Journal of Porphyrins and Phthalocyanines 23, no. 04n05 (April 2019): 526–33. http://dx.doi.org/10.1142/s1088424619500469.

Full text

Abstract:

Porphyrins and metalloporphyrins are one of the most widely studied platforms for the construction of supramolecular structures. These compounds have an extended aromatic system that allows [Formula: see text]–[Formula: see text] stacking interactions which, together with hydrogen bonds, electrostatic forces and the formation of inter-metallic complexes arising from peripheral groups, offer a versatile platform to control the self-assembly mechanism. In this work, we present the study of nanostructures formed by self-assembly of the water-soluble porphyrins meso-tetra([Formula: see text]-methyl-4-pyridyl)porphyrin (TMPyP) and meso-tetra(4-sulfonatophenyl)porphyrin (TPPS) in the presence of hard nanotemplates. Different nanoparticles (silica, gold, and polystyrene), concentrations and synthetic procedures were explored. The obtained materials were characterized by SEM and AFM microscopies, UV-vis absorption spectroscopy and dynamic light scattering measurements. A clear modification of the SiO2 NP surface roughness using one-pot synthesis was observed. The results were variable depending on the porphyrin–surface interactions and concentrations used. At lower porphyrin concentrations, a shift of the Soret band was observed, while at higher concentrations, free NS were formed. This reflects a competition between surface and solution directed self-assembly.

APA, Harvard, Vancouver, ISO, and other styles

47

Byrne, CJ, and AD Ward. "The Preparation of Analogs of the Ether-Linked Dimer and Oligomer Components of Hematoporphyrin Derivative." Australian Journal of Chemistry 44, no. 3 (1991): 411. http://dx.doi.org/10.1071/ch9910411.

Full text

Abstract:

The preparation of ether-linked porphyrin dimers and oligomers which are analogues of those present in the anticancer drugs hematoporphyrin derivative and Photofrin IIR is described. These materials are prepared from the appropriately substituted porphyrins containing a 1-hydroxyethyl or a vinyl side chain through an intermediate 1-bromoethyl derivative. Ether-linked porphyrin dimers with ethyl, formyl , hydroxymethyl and 1-alkoxyethyl side chains were prepared, together with trimers and tetramers containing ethyl side chains. Some of the spectroscopic and biological properties of these compounds are discussed.

APA, Harvard, Vancouver, ISO, and other styles

48

Vzorov, Andrei N., Dabney W. Dixon, Jenna S. Trommel, Luigi G. Marzilli, and Richard W. Compans. "Inactivation of Human Immunodeficiency Virus Type 1 by Porphyrins." Antimicrobial Agents and Chemotherapy 46, no. 12 (December 2002): 3917–25. http://dx.doi.org/10.1128/aac.46.12.3917-3925.2002.

Full text

Abstract:

ABSTRACT We have evaluated the anti-human immunodeficiency virus (HIV) activity of a series of natural and synthetic porphyrins to identify compounds that could potentially be used as microbicides to provide a defense against infection by sexually transmitted virus. For assays we used an epithelial HeLa-CD4 cell line with an integrated long terminal repeat-β-galactosidase gene. For structure-activity analysis, we divided the porphyrins tested into three classes: (i) natural porphyrins, (ii) metallo-tetraphenylporphyrin tetrasulfonate (metallo-TPPS4) derivatives, and (iii) sulfonated tetra-arylporphyrin derivatives. None of the natural porphyrins studied reduced infection by more than 80% at a concentration of 5 μg/ml in these assays. Some metal chelates of TPPS4 were more active, and a number of sulfonated tetra-aryl derivatives showed significantly higher activity. Some of the most active compounds were the sulfonated tetranaphthyl porphyrin (TNapPS), sulfonated tetra-anthracenyl porphyrin (TAnthPS), and sulfonated 2,6-difluoro-meso-tetraphenylporphine [TPP(2,6-F2)S] and its copper chelate [TPP(2,6-F2)S,Cu], which reduced infection by 99, 96, 94, and 96%, respectively. Our observations indicate that at least some of these compounds are virucidal, i.e., that they render the virus noninfectious. The active compounds were found to inhibit binding of the HIV type 1 gp120 to CD4 and also to completely inhibit the ability of Env proteins expressed from recombinant vectors to induce cell fusion with receptor-bearing target cells. These results support the conclusion that modified porphyrins exhibit substantial activity against HIV and that their target is the HIV Env protein.

APA, Harvard, Vancouver, ISO, and other styles

49

Walter, Michael G., Alexander B. Rudine, and Carl C. Wamser. "Porphyrins and phthalocyanines in solar photovoltaic cells." Journal of Porphyrins and Phthalocyanines 14, no. 09 (September 2010): 759–92. http://dx.doi.org/10.1142/s1088424610002689.

Full text

Abstract:

This review summarizes recent advances in the use of porphyrins, phthalocyanines, and related compounds as components of solar cells, including organic molecular solar cells, polymer cells, anddye-sensitized solar cells. The recent report of a porphyrin dye that achieves 11% power conversion efficiency in a dye-sensitized solar cell indicates that these classes of compounds can be as efficient as the more commonly used ruthenium bipyridyl derivatives.

APA, Harvard, Vancouver, ISO, and other styles

50

BAKER, GARY A., FRANK V. BRIGHT, MICHAEL R. DETTY, SIDDHARTH PANDEY, COREY E. STILTS, and HUIRONG YAO. "The influence of phenylethynyl linkers on the photo-physical properties of metal-free porphyrins." Journal of Porphyrins and Phthalocyanines 04, no. 07 (November 2000): 669–83. http://dx.doi.org/10.1002/1099-1409(200011)4:7<669::aid-jpp287>3.0.co;2-m.

Full text

Abstract:

Series of 5,10,15,20-tetraarylporphyrins 1 and 5,10,15,20-tetrakis[4-(arylethynyl)phenyl]porphyrins 2 were prepared via condensation of pyrrole with the appropriate benzaldehyde or 4-(arylethynyl)benzaldehyde derivative (3). Condensation of meso-phenyldipyrromethane with mixtures of benzaldehyde and 4-(trimethylsilyl-ethynyl)benzaldehyde gave a separable mixture of mono- (6), bis- (both cis-7 and trans-8) and tris[4-(trimethylsilylethynyl)phenyl]porphyrin (9). Following removal of the trimethylsilyl groups of 6–9, the 4-ethynylphenyl groups of 11–14 were coupled to 1-iodo-3,5-di(trifluoromethyl)benzene with Pd ( OAc )2 to give 15–18 bearing one, two (both cis- and trans-) and three 4-[bis-3,5-(trifluoromethyl)phenylethynyl]phenyl groups respectively. Coupling of 11 and 1-iodo-4-nitrobenzene with Pd ( OAc )2 gave porphyrin 19 with one 4-(4-nitrophenylethynyl)phenyl group. Porphyrin 24 with a p-quinone linked to the porphyrin core via a phenylethynyl group was prepared via similar chemistry. The absorbance spectra, emission maxima, excited-state fluorescence lifetimes, quantum yields of fluorescence, rates of fluorescence and rates of non-radiative decay were measured for each of the porphyrins. Absorbance spectra and emission maxima were nearly identical for all the porphyrins of this study, which suggests that the aryl groups and 4-(arylethynyl)phenyl groups are not strongly coupled to the porphyrin core in these metal-free compounds. Fluorescence quantum yields and rates of radiative decay were larger for porphyrins bearing 4-(arylethynyl)phenyl groups, while excited-state fluorescence lifetimes were somewhat shorter. These effects were additive for each additional 4-(arylethynyl)phenyl group.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Porphyrin compounds'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles