Syntheses and photochemical properties of octasubstituted phthalocyaninato zinc complexes

2001 ◽  
Vol 05 (11) ◽  
pp. 782-792 ◽  
Author(s):  
SUZANNE E. MAREE ◽  
TEBELLO NYOKONG
Keyword(s):  
Thin Layer ◽  
Singlet Oxygen ◽  
Electrochemical Reduction ◽  
Zinc Complexes ◽  
Quantum Yields ◽  
Photochemical Properties ◽  
High Concentrations ◽  
Electron Donating Groups ◽  
Selection Of

In this work a selection of octasubstituted phthalocyaninato zinc complexes were synthesized and their photochemistry studied. The substituents included cholesterol (3a), estrone (3b), naphthol (3c) and phenoxy groups substituted with CH3 (3d), C ( CH 3)3 (at two positions, 3e), C ( CH 3)3 (3f), NO2 (3g), NH 2 (3h), COH (3i), COOH (3j), and H (3k). In general, complexes containing electron-donating groups attached to the phenoxy ring (e.g. 3e and 3f) were found to be photochemically unstable with photobleaching quantum yields of the order of 10-3. In the presence of electron-withdrawing groups (3g, 3i, and 3j) the photobleaching quantum yields were of the order of 10-6 to 10-5. Singlet oxygen quantum yields (ΦΔ) ranged from 0.01 to 0.73. The lowest ΦΔ was observed for the highly aggregated complex 3c. All the complexes showed aggregation at high concentrations. Electrochemical reduction using a thin-layer spectroelectrochemistry cell showed that the complexes become more monomeric following reduction.

New soluble 4-(4-formyl-2,6-dimethoxyphenoxy) substituted phthalocyanines: Synthesis, characterization, photophysical and photochemical properties

2021 ◽  
pp. 1-10
Author(s):  
Ibrahim Erden ◽  
Betül Karadoğan ◽  
Fatma Aytan Kılıçarslan ◽  
Göknur Yaşa Atmaca ◽  
Ali Erdoğmuş
Keyword(s):  
Quantum Yield ◽  
Singlet Oxygen ◽  
Fluorescence Quantum Yield ◽  
Metal Ion ◽  
Mass Spectra ◽  
Quantum Yields ◽  
Therapeutic Outcomes ◽  
Ft Ir ◽  
Photochemical Properties ◽  
New Compounds

This work describes the synthesis, spectral and fluorescence properties of bis 4-(4-formyl-2,6-dimethoxyphenoxy) substituted zinc (ZnPc) and magnesium (MgPc) phthalocyanines. The new compounds have been characterized by elemental analysis, UV-Vis, FT-IR, 1H-NMR and mass spectra. Afterward, the effects of including metal ion on the photophysicochemical properties of the complexes were studied in biocompatible solvent DMSO to analyze their potential to use as a photosensitizer in photodynamic therapy (PDT). The fluorescence and singlet oxygen quantum yields were calculated as 0.04–0.15 and 0.70–0.52 for ZnPc and MgPc, respectively. According to the results, MgPc has higher fluorescence quantum yield than ZnPc, while ZnPc has higher singlet oxygen quantum yield than MgPc. The results show that the synthesized complexes can have therapeutic outcomes for cancer treatment.

New peripherally substituted lutetium mono and bis phthalocyanines: Synthesis and comparative photophysical and photochemical properties

2019 ◽  
Vol 23 (11n12) ◽  
pp. 1542-1550
Author(s):  
Nagihan Kocaağa ◽  
Öznur Dülger Kutlu ◽  
Ali Erdoğmuş
Keyword(s):  
Mass Spectrometry ◽  
Photodynamic Therapy ◽  
Singlet Oxygen ◽  
Photophysical Properties ◽  
Quantum Yields ◽  
Synthesis And Characterization ◽  
Type Ii ◽  
H Nmr ◽  
Photochemical Properties

In this study, the synthesis and characterization of mono-(phthalocyaninato) lutetium(III) (1-Cl and 1-F) [Lu[Formula: see text](AcO)(Pc)] (Pc [Formula: see text] phthalocyaninato, AcO [Formula: see text] acetate) and bis-(phthalocyaninato) lutetium(III) (2-Cl and 2-Br) [Lu[Formula: see text]Pc[Formula: see text]] bearing halogenated (F, Cl and Br) phenoxy–phenoxy groups are described and verified by IR, [Formula: see text]H-NMR, UV-vis and mass spectrometry. Photochemical and photophysical properties of 1-F, 1-Cl 2-Cl and 2-Br in DMSO are also presented. A comparison between photophysical and photochemical parameters of mono and bis derivatives showed that mono phthalocyanines are better photosensitizers than bis phthalocyanines. Photophysical and photochemical properties of phthalocyanines are very useful for photodynamic therapy applications. Singlet oxygen quantum yields [Formula: see text] give an indication of the potential of the complexes as photosensitizers in photodynamic therapy applications. The chloro, fluoro, bromo-phenoxy–phenoxy substituted mono-(phthalocyaninato) lutetium(III) complexes (1-Cl and 1-F) gave good singlet oxygen quantum yields (from 0.86 to 0.80) in DMSO. Thus, these complexes show potential as Type II photosensitizers for PDT of cancer.

scholarly journals Red and Near-Infrared Absorbing Dicyanomethylene Squaraine Cyanine Dyes: Photophysicochemical Properties and Anti-Tumor Photosensitizing Effects

Materials ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2083
Author(s):  
Tiago D. Martins ◽  
Eurico Lima ◽  
Renato E. Boto ◽  
Diana Ferreira ◽  
José R. Fernandes ◽  
...  
Keyword(s):  
Singlet Oxygen ◽  
Near Infrared ◽  
Cyanine Dyes ◽  
Quantum Yields ◽  
Squaraine Dyes ◽  
Photodynamic Activity ◽  
Photochemical Properties ◽  
Radiation Treatments ◽  
Species Production

Photodynamic therapy is a medical modality developed for the treatment of several diseases of oncological and non-oncological etiology that requires the presence of a photosensitizer, light and molecular oxygen, which combined will trigger physicochemical reactions responsible for reactive oxygen species production. Given the scarcity of photosensitizers that exhibit desirable characteristics for its potential application in this therapeutic strategy, the main aims of this work were the study of the photophysical and photochemical properties and the photobiological activity of several dicyanomethylene squaraine cyanine dyes. Thus, herein, the study of their aggregation character, photobleaching and singlet oxygen production ability, and the further application of the previously synthesized dyes in Caco-2 and HepG2 cancer cell lines, to evaluate their phototherapeutic effects, are described. Dicyanomethylene squaraine dyes exhibited moderate light-stability and, despite the low singlet oxygen quantum yields, were a core of dyes that exhibited relevant in vitro photodynamic activity, as there was an evident increase in the toxicity of some of the tested dyes exclusive to radiation treatments.

Synthesis and characterization of novel 7-oxy-3-ethyl-6-hexyl-4-methylcoumarin substituted metallo phthalocyanines and investigation of their photophysical and photochemical properties

2019 ◽  
Vol 48 (34) ◽  
pp. 13046-13056 ◽  
Author(s):  
Mücahit Özdemir ◽  
Begümhan Karapınar ◽  
Bahattin Yalçın ◽  
Ümit Salan ◽  
Mahmut Durmuş ◽  
...  
Keyword(s):  
Singlet Oxygen ◽  
Quantum Yields ◽  
Synthesis And Characterization ◽  
Photochemical Properties ◽  
Lipophilic Groups

Coumarin functionalized metallo phthalocyanines shows increased singlet oxygen quantum yields when included lipophilic groups.

Synthesis, DNA photocleavage, singlet oxygen photogeneration and two photon absorption properties of ruthenium-phenanthroline porphyrins

2015 ◽  
Vol 19 (09) ◽  
pp. 1046-1052 ◽  
Author(s):  
Ze-Bin Xu ◽  
Fa-Quan Yu ◽  
Fengshou Wu ◽  
Heng Zhang ◽  
Kai Wang ◽  
...  
Keyword(s):  
Singlet Oxygen ◽  
Cross Section ◽  
Therapeutic Agents ◽  
Photon Absorption ◽  
Quantum Yields ◽  
Absorption Properties ◽  
Dna Photocleavage ◽  
Two Photon Absorption ◽  
Two Photon ◽  
Photochemical Properties

Through a new synthetic route, three ruthenium-phenanthroline porphyrins (RPP1, RPP2 and RPP3) were prepared. Their photophysical and photochemical properties, such as DNA photocleavage activity, singlet-oxygen photogeneration and two-photon absorption (2PA) were evaluated. These porphyrins 1–3 had substantial photocleavage activities, with 71%, 74% and 38% observed at 20 μM. The porphyrins with different substituents on phenathroline group had similar singlet oxygen quantum yields, with ΦΔ values at 0.52, 0.47 and 0.41, respectively. The 2PA cross-section (σ(2)) values of RPP 1–3, measured by the Z-scan method, were calculated to be 152, 172 and 135 GM, respectively, which were around 5-fold higher than that of H2TPP . Thus, these porphyrins, with their good photocleavage activities, 1 O 2 quantum yields and high 2PA cross section, suggest great potential as photodynamic therapeutic agents.

Influence of protonation of peripheral substituents on photophysical and photochemical properties of tetrapyrazinoporphyrazines

2010 ◽  
Vol 14 (07) ◽  
pp. 582-591 ◽  
Author(s):  
Veronika Novakova ◽  
Eva H. Mørkved ◽  
Miroslav Miletin ◽  
Petr Zimcik
Keyword(s):  
Charge Transfer ◽  
Sulfuric Acid ◽  
Singlet Oxygen ◽  
Electron Pair ◽  
Intramolecular Charge Transfer ◽  
Quantum Yields ◽  
Considerable Decrease ◽  
Fluorescence Quantum Yields ◽  
Photochemical Properties ◽  
Free Electron Pair

Octasubstituted zinc tetrapyrazinoporphyrazines with four N,N-dimethylaminophenyls and four phenyl or pyridin-3-yl substituents were synthesized and fully characterized. Their fluorescence quantum yields in DMF or pyridine were very low, almost undetectable, as a consequence of ultrafast intramolecular charge transfer. Titration of their DMF solutions with sulfuric acid led to increase of the fluorescence quantum yields by two orders of magnitude when the full protonation of peripheral substituents was achieved. Intramolecular charge transfer is no longer a favorable way of excited-state relaxation at full protonation of N,N-dimethylaminophenyl substituents because of loss of donor centers (free electron pair on its nitrogen). Similarly, singlet oxygen quantum yields also increased by two orders of magnitude when sulfuric acid was added to tetrapyrazinoporphyrazine solutions in DMF. Protonation at azomethine nitrogens of tetrapyrazinoporphyrazine macrocycle was observed at higher acid concentrations and it led to considerable decrease of fluorescence quantum yields. Octaphenyl zinc tetrapyrazinoporphyrazine and octa(pyridin-3-yl) zinc tetrapyrazinoporphyrazine were used as controls without intramolecular charge transfer. Their fluorescence and singlet oxygen quantum yields were high in DMF and decreased at higher concentrations of sulfuric acid due to protonation of azomethine nitrogens. The results suggest that the photophysical and photochemical properties of studied compounds may be controlled by changes of pH of medium.

Bis-indole substituted phthalocyanines: Photophysical and photochemical properties

2020 ◽  
Vol 25 (01) ◽  
pp. 66-74
Author(s):  
Kevser Harmandar ◽  
Esra N. Kaya ◽  
Mehmet F. Saglam ◽  
Ibrahim F. Sengul ◽  
Devrim Atilla
Keyword(s):  
Photodynamic Therapy ◽  
Singlet Oxygen ◽  
Spectral Data ◽  
Quantum Yields ◽  
Oxygen Generation ◽  
Fluorescence Quantum Yields ◽  
H Nmr ◽  
Singlet Oxygen Generation ◽  
Photochemical Properties ◽  
C Nmr

Tetra substituted peripheral and non-peripheral Zn(II) phthalocyanines were successfully synthesized employing 4-(bis(3-methyl-1H-indol-2-yl)methyl)phenol as a starting material. The structure of these synthesized compounds was confirmed using 1H NMR, [Formula: see text]C NMR, infrared (IR), UV-vis, and MALDI-TOF spectral data. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen generation) properties of all synthesized peripheral and non-peripheral compounds were investigated in order to determine the potential of these compounds for application in photodynamic therapy.

Photochemical properties of substituted tetraazachlorins

2014 ◽  
Vol 18 (06) ◽  
pp. 457-464 ◽  
Author(s):  
Anton P. Lastovoy ◽  
Nina A. Kuznetsova ◽  
Ludmila K. Slivka ◽  
Elena A. Makarova
Keyword(s):  
Singlet Oxygen ◽  
Colloidal Solution ◽  
Quantum Yields ◽  
Aromatic Rings ◽  
Oxygen Generation ◽  
Singlet Oxygen Generation ◽  
Micelle Core ◽  
Photodegradation Mechanism ◽  
Photochemical Properties ◽  
Aqueous Micellar Solutions

The photochemical properties of water-insoluble metal-free tetraazachlorin derivatives in organic solvents and aqueous micellar solutions of nonionic surfactants were investigated. The quantum yields of fluorescence, singlet oxygen generation and photodegradation were evaluated in benzene. The highest photostability and singlet oxygen quantum yield (ΦΔ = 0.7) was found for 2,2,3,3-tetramethyl-7,8,12,13,17,18-hexaphenyltetraazachlorin. The moderate ΦΔ values (0.21–0.35) of triarenotetraazachlorins in benzene were established. Expansion of tetraazachlorin π-system by fusion of three aromatic rings leads to reduction of efficiency of singlet oxygen generation. The study of photodegradation mechanism shows that radical photooxidation apparently is most plausible, though 1 O 2 may partly contribute to photodestruction of some tetraazachlorins. In aqueous colloidal solution of nonionic surfactant (Cremophor EL) the same, as in benzene, effect of sensitizer structure upon efficacy of singlet oxygen production was observed. It was shown that 1 O 2 diffusion from micelle core into solution and then to target slows its oxidation rate substantially in comparison to the case where sensitizer and target are localized in the same micelle.

Azaphthalocyanines with extended conjugation through heteroaryl and aryl substituents: Photochemical and photophysical properties

2007 ◽  
Vol 11 (02) ◽  
pp. 130-138 ◽  
Author(s):  
Eva H. Mørkved ◽  
Nils Kr. Afseth ◽  
Petr Zimcik
Keyword(s):  
Singlet Oxygen ◽  
Absorption Spectra ◽  
Photophysical Properties ◽  
Point Of View ◽  
Zinc Complexes ◽  
Quantum Yields ◽  
Sterical Hindrance ◽  
20 Nm ◽  
Mg Complexes

Magnesium and zinc complexes of azaphthalocyanines (AzaPc) with eight peripheral aromatic (phenyl) or heteroaromatic (pyridyl, thienyl, furyl) substituents are studied from the point of view of their singlet oxygen (ΦΔ) and fluorescence (Φ F ) quantum yields, and UV-vis absorption spectra. Zn complexes have higher ΦΔ than Mg complexes by a factor of two, whereas the Mg complexes have higher Φ F than Zn complexes, also by a factor of two. Thienyl AzaPc have the highest ΦΔ among all studied substances (0.635 for Zn complex) followed by phenyl and pyridyl derivatives. The order of Φ F values is then reversed - the highest values were reached for pyridyl and phenyl derivatives followed by thienyl AzaPc. Both furyl AzaPc were unstable towards light and decomposed giving very low ΦΔ and Φ F . The Q-bands of the furyl and thienyl AzaPc were red-shifted for approx. 20 nm compared to phenyl and pyridyl derivatives indicating lower sterical hindrance between five-membered rings and thus allowing better conjugation of π-systems. Pyridyl-, thienyl- and furyl-substituted pyrazino[2,3-b]pyrazine-2,3-dicarbonitriles were also prepared but decomposed during attempted cyclotetramerizations.

Novel carboxylic acid terminated silicon(IV) and zinc(II) phthalocyanine photosensitizers: Synthesis, photophysical and photochemical studies

2018 ◽  
Vol 22 (11) ◽  
pp. 1010-1021 ◽  
Author(s):  
Arif Hışır ◽  
Gülşah Gümrükcü Köse ◽  
Göknur Yaşa Atmaca ◽  
Ali Erdoğmuş ◽  
Gülnur Keser Karaoğlan
Keyword(s):  
Carboxylic Acid ◽  
Singlet Oxygen ◽  
Quantum Yields ◽  
Cooh Group ◽  
Experimental Conditions ◽  
Oxygen Generation ◽  
Fluorescence Quantum Yields ◽  
H Nmr ◽  
Silicon Phthalocyanines ◽  
Photochemical Properties

In order to improve the efficacy of photochemical properties for photodynamic therapy (PDT) applications, carboxylic acid groups axially conjugated with silicon(IV) and at the peripheral position with zinc(II) phthalocyanine skeletons for new photosensitizers to investigate the influence of the COOH group positions on the photophysicochemical performance are described in this study. Silicon (IV) (3 and 5) and zinc (II) (7) phthalocyanines were characterized by UV-vis, FTIR, 1H-NMR, MALDI-TOF MS and elemental analysis spectral data. Furthermore, the photophysical (fluorescence quantum yields and fluorescence quenching studies), photochemical (photodegradation and singlet oxygen generation) and aggregation properties of the newly synthesized phthalocyanines were investigated in dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) solutions. The results were compared with that of zinc and silicon phthalocyanines. Singlet oxygen quantum yields ranged from 0.23 to 0.63 via Type II mechanism under the experimental conditions studied. The fluorescence of the phthalocyanine complexes (3, 5 and 7) is effectively quenched by 1,4-benzoquinone (BQ) in DMSO, DMF and THF.

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