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1.
Molecules ; 26(17)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34500746

RESUMO

In this study, we report the preparation of new mono-charged benzoporphyrin complexes by reaction of the appropriate neutral benzoporphyrin with (2,2'-bipyridine)dichloroplatinum(II) and of the analogs' derivatives synthesized through alkylation of the neutral scaffold with iodomethane. All derivatives were incorporated into polyvinylpyrrolidone (PVP) micelles. The ability of the resultant formulations to generate reactive oxygen species was evaluated, mainly the singlet oxygen formation. Then, the capability of the PVP formulations to act as photosensitizers against bladder cancer cells was assessed. Some of the studied formulations were the most active photosensitizers causing a decrease in HT-1376 cells' viability. This creates an avenue to further studies related to bladder cancer cells.

2.
J Photochem Photobiol B ; 222: 112258, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34399205

RESUMO

Photodynamic therapy (PDT) is an approved therapeutic approach and an alternative to conventional chemotherapy for the treatment of several types of cancer with the advantages of reducing the side effects and developing resistance mechanisms. Here, was evaluated the photosensitization capabilities of 5,10,15,20-tetrakis[4-(pyridinium-1-yl-methyl)phenyl]porphyrin (3), its N-confused isomer (4) and of the neutral precursors (1) and (2) and the results were compared with the ones obtained with the cationic 5,10,15,20-tetrakis(1-methylpyridinium-4-yl)porphyrin (TMPyP). Both regular porphyrin derivatives 1 and 3 showed higher efficiency to generate singlet oxygen than TMPyP. The PDT assays towards MCF-7 cells under red light irradiation (λ > 640 nm, 23.7 mW cm-2) demonstrated that the cationic porphyrin 3 is an efficient photosensitizer to kill MCF-7 breast cancer cells. The study of the cell death mechanisms induced by the photodynamic process showed that the studied porphyrin 3 and TMPyP caused cell death by autophagic flux and necrosis.


Assuntos
Apoptose/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Apoptose/efeitos da radiação , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Feminino , Humanos , Luz , Células MCF-7 , Microscopia Confocal , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/química , Porfirinas/uso terapêutico , Oxigênio Singlete/metabolismo
3.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34445313

RESUMO

High levels of hyaluronic acid (HA) in tumors correlate with poor outcomes with several types of cancers due to HA-driven support of adhesion, migration and proliferation of cells. In this study we explored how to enhance the degradation of HA into low-molecular fragments, which cannot prevent the immune system to fight tumor proliferation and metastases. The physiological solution of HA was exposed to oxidative degradation by ascorbate and cupric ions in the presence of either one of three ortho isomeric Mn(III) substituted N-alkyl- and alkoxyalkylpyridylporphyrins or para isomeric Mn(III) N-methylpyridyl analog, commonly known as mimics of superoxide dismutase. The changes in hyaluronan degradation kinetics by four Mn(III) porphyrins were monitored by measuring the alteration in the dynamic viscosity of the HA solution. The ortho compounds MnTE-2-PyP5+ (BMX-010, AEOL10113), MnTnBuOE-2-PyP5+ (BMX-001) and MnTnHex-2-PyP5+ are able to redox cycle with ascorbate whereby producing H2O2 which is subsequently coupled with Cu(I) to produce the •OH radical essential for HA degradation. Conversely, with the para analog, MnTM-4-PyP5+, no catalysis of HA degradation was demonstrated, due to its inertness towards redox cycling with ascorbate. The impact of different Mn(III)-porphyrins on the HA decay was further clarified by electron paramagnetic resonance spectrometry. The ability to catalyze the degradation of HA in a biological milieu, in the presence of cupric ions and ascorbate under the conditions of high tumor oxidative stress provides further insight into the anticancer potential of redox-active ortho isomeric Mn(III) porphyrins.


Assuntos
Ácido Ascórbico/química , Ácido Hialurônico/química , Metaloporfirinas/química , Cobre/química , Magnésio/química , Oxirredução , Superóxido Dismutase/metabolismo
4.
Int J Mol Sci ; 22(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923523

RESUMO

Microorganisms, usually bacteria and fungi, grow and spread in skin wounds, causing infections. These infections trigger the immune system and cause inflammation and tissue damage within the skin or wound, slowing down the healing process. The use of photodynamic therapy (PDT) to eradicate microorganisms has been regarded as a promising alternative to anti-infective therapies, such as those based on antibiotics, and more recently, is being considered for skin wound-healing, namely for infected wounds. Among the several molecules exploited as photosensitizers (PS), porphyrinoids exhibit suitable features for achieving those goals efficiently. The capability that these macrocycles display to generate reactive oxygen species (ROS) gives a significant contribution to the regenerative process. ROS are responsible for avoiding the development of infections by inactivating microorganisms such as bacteria but also by promoting cell proliferation through the activation of stem cells which regulates inflammatory factors and collagen remodeling. The PS can act solo or combined with several materials, such as polymers, hydrogels, nanotubes, or metal-organic frameworks (MOF), keeping both the microbial photoinactivation and healing/regenerative processes' effectiveness. This review highlights the developments on the combination of PDT approach and skin wound healing using natural and synthetic porphyrinoids, such as porphyrins, chlorins and phthalocyanines, as PS, as well as the prodrug 5-aminolevulinic acid (5-ALA), the natural precursor of protoporphyrin-IX (PP-IX).


Assuntos
Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas/farmacologia , Reepitelização , Dermatopatias Infecciosas/terapia , Animais , Humanos , Fármacos Fotossensibilizantes/química , Protoporfirinas/química , Pele/efeitos dos fármacos , Pele/metabolismo
5.
Molecules ; 26(2)2021 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-33477299

RESUMO

New porphyrin-pyrrolidine/pyrroline conjugates were prepared by revisiting 1,3-dipolar cycloaddition reactions between a porphyrinic azomethine ylide and a series of dipolarophiles. Cationic conjugates obtained by alkylation of the pyrrolidine/pyrroline cycloadducts showed ability to generate singlet oxygen and to produce iodine in presence of KI when irradiated with visible light. Some of the cationic derivatives showed photobactericidal properties towards a Gram-negative bioluminescent E. coli. In all cases, these features were significantly improved using KI as coadjutant, allowing, under the tested conditions, the photoinactivation of the bacterium until the detection limit of the method with a drastic reduction of the required photosensitizer concentration and irradiation time. The obtained results showed a high correlation between the ability of the cationic porphyrin derivative to produce singlet oxygen and iodine and its E. coli photoinactivation profile.


Assuntos
Antibacterianos , Escherichia coli/crescimento & desenvolvimento , Fármacos Fotossensibilizantes , Porfirinas/química , Pirróis/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Oxigênio Singlete/química
6.
Int J Mol Sci ; 22(1)2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33379392

RESUMO

The concept behind photodynamic therapy (PDT) is being successfully applied in different biomedical contexts such as cancer diseases, inactivation of microorganisms and, more recently, to improve wound healing and tissue regeneration. The effectiveness of PDT in skin treatments is associated with the role of reactive oxygen species (ROS) produced by a photosensitizer (PS), which acts as a "double agent". The release of ROS must be high enough to prevent microbial growth and, simultaneously, to accelerate the immune system response by recruiting important regenerative agents to the wound site. The growing interest in this subject is reflected by the increasing number of studies concerning the optimization of relevant experimental parameters for wound healing via PDT, namely, light features, the structure and concentration of the PS, and the wound type and location. Considering the importance of developing PSs with suitable features for this emergent topic concerning skin wound healing, in this review, a special focus on the achievements attained for each PS class, namely, of the non-porphyrinoid type, is given.


Assuntos
Fármacos Fotossensibilizantes/farmacologia , Pele/patologia , Cicatrização/efeitos dos fármacos , Animais , Humanos , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Porfirinas , Espécies Reativas de Oxigênio , Pele/efeitos dos fármacos
7.
Bioorg Chem ; 101: 103994, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32569896

RESUMO

The synthesis of new porphyrin-indazole hybrids by a Knoevenagel condensation of 2-formyl-5,10,15,20-tetraphenylporphyrin and N-methyl-nitroindazolylacetonitrile derivatives is reported. The target compounds were isolated in moderate to good yields (32-57%) and some of the isolated porphyrin-indazole conjugates showed good performance in the generation of singlet oxygen when irradiated with visible light. Their efficiency as photosensitizers in the photoinactivation of methicillin resistant Staphylococcus aureus-MRSA was evaluated. All derivatives showed to be able to photoinactivate the MRSA bacteria. Compound 3a appears to be the most promising photosensitiser (PS) in the photoinactivation of these bacteria, despite being the least efficient in singlet oxygen generation. The addition of potassium iodide (KI) significantly potentiated the antimicrobial Photodynamic Therapy (aPDT) process mediated by all the analysed porphyrin-indazole conjugates. The combined action of nitroindazole-porphyrins with potassium iodide (KI) action appears to be promising in the photoinactivation of MRSA.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Indazóis/química , Indazóis/farmacologia , Porfirinas/química , Porfirinas/farmacologia , Antibacterianos/síntese química , Indazóis/síntese química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/síntese química , Oxigênio Singlete/química , Análise Espectral/métodos
8.
Molecules ; 25(7)2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32260294

RESUMO

Azides and porphyrinoids (such as porphyrin and corrole macrocycles) can give rise to new derivatives with significant biological properties and as new materials' components. Significant synthetic approaches have been studied. A wide range of products (e.g., microporous organic networks, rotaxane and dendritic motifs, dendrimers as liquid crystals, as blood substitutes for transfusions and many others) can now be available and used for several medicinal and industrial purposes.


Assuntos
Azidas/química , Porfirinas/química , Estrutura Molecular
9.
Molecules ; 25(7)2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32290240

RESUMO

The reaction between organic azides and alkyne derivatives via the Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) is an efficient strategy to combine phthalocyanines and analogues with different materials. As examples of such materials, it can be considered the following ones: graphene oxide, carbon nanotubes, silica nanoparticles, gold nanoparticles, and quantum dots. This approach is also being relevant to conjugate phthalocyanines with carbohydrates and to obtain new sophisticated molecules; in such way, new systems with significant potential applications become available. This review highlights recent developments on the synthesis of phthalocyanine, subphthalocyanine, and porphyrazine derivatives where CuAAC reactions are the key synthetic step.


Assuntos
Azidas/química , Indóis/química , Azidas/síntese química , Catálise , Técnicas de Química Sintética , Química Click , Eletrodos , Indóis/síntese química , Estrutura Molecular , Polímeros/química
10.
Molecules ; 25(3)2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31972976

RESUMO

Natural and synthetic macrocycles like porphyrins, corroles and phthalocyanines are considered strong candidates to be used in different fields, such as catalysis, sensing, medicine, materials science, or in the development of advanced biomimetic models. All these applications are strongly dependent on the availability of compounds with adequate and specific structural features. This Special Issue has collected 13 contributions which consolidate and expand our knowledge on the application of these macrocycles in different fields accompanied by innovative synthetic methodologies to afford and to functionalize this type of compounds.


Assuntos
Compostos Macrocíclicos/síntese química , Tetrapirróis/síntese química , Catálise , Compostos Macrocíclicos/química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/síntese química , Porfirinas/química , Telomerase/metabolismo , Tetrapirróis/química
11.
Int J Mol Sci ; 20(10)2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31121942

RESUMO

The post-functionalization of 5,10,15-tris(1-methylpyridinium-4-yl)-20-(pentafluorophenyl)porphyrin tri-iodide, known as a highly efficient photosensitizer (PS) for antimicrobial photodynamic therapy (aPDT), in the presence of 3- or 4-mercaptobenzoic acid, afforded two new tricationic porphyrins with adequate carboxylic pending groups to be immobilized on chitosan or titanium oxide. The structural characterization of the newly obtained materials confirmed the success of the porphyrin immobilization on the solid supports. The photophysical properties and the antimicrobial photodynamic efficacy of the non-immobilized porphyrins and of the new conjugates were evaluated. The results showed that the position of the carboxyl group in the mercapto units or the absence of these substituents in the porphyrin core could modulate the action of the photosensitizer towards the bioluminescent Gram-negative Escherichia coli bacterium. The antimicrobial activity was also influenced by the interaction between the photosensitizer and the type of support (chitosan or titanium dioxide). The new cationic porphyrins and some of the materials were shown to be very stable in PBS and effective in the photoinactivation of E. coli bacterium. The physicochemical properties of TiO2 allowed the interaction of the PS with its surface, increasing the absorption profile of TiO2, which enables the use of visible light, inactivating the bacteria more efficiently than the corresponding PS immobilized on chitosan.


Assuntos
Antibacterianos/química , Quitosana/análogos & derivados , Fármacos Fotossensibilizantes/química , Porfirinas/química , Titânio/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Cátions/síntese química , Cátions/química , Cátions/farmacologia , Quitosana/síntese química , Quitosana/farmacologia , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Humanos , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/síntese química , Porfirinas/farmacologia , Titânio/farmacologia
12.
Molecules ; 24(4)2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30769770

RESUMO

Porphyrins show great promise for future purification demands. This is largely due to their unique features as host binding molecules that can be modified at the synthetic level, and largely improved by their incorporation into inorganic based materials. In this study, we assessed the efficacy of a hybrid material obtained from the immobilization of 5,10,15,20-tetrakis(pentafluorophenyl)-porphyrin on silica surface to remove Pb(II), Cu(II), Cd(II), and Zn(II) ions from water. The new organic-inorganic hybrid adsorbent was fully characterized by adequate techniques and the results show that the hybrid exhibits good chemical and thermal stability. From batch assays, it was evaluated how the efficacy of the hybrid was affected by the pH, contact time, initial metal concentration, and temperature. The adsorption kinetic and isotherms showed to fit the recent developed fractal-like pseudo-second-order model and Langmuir⁻Freundlich model respectively. The highest adsorption capacities for Pb(II), Cu(II), Cd(II), and Zn(II) ions were 187.36, 125.17, 82.45, and 56.23 mg g-1, respectively, at pH 6.0 and 25 °C. This study also shows that metal cations from real river water samples can be efficient removed in the presence of the new adsorbent material.


Assuntos
Metais Pesados/isolamento & purificação , Porfirinas/química , Purificação da Água , Água/química , Cádmio/química , Cádmio/isolamento & purificação , Cobre/química , Cobre/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , Íons/química , Íons/isolamento & purificação , Cinética , Chumbo/química , Chumbo/isolamento & purificação , Metais Pesados/toxicidade , Dióxido de Silício , Poluentes Químicos da Água
13.
Molecules ; 25(1)2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31905680

RESUMO

The alkylation of a series of nitroindazole derivatives with 1,2-dibromoethane afforded the corresponding N-(2-bromoethyl)- and N-vinyl-nitro-1H-indazoles. The Cu(I)-catalysed azide- alkyne 1,3-dipolar cycloaddition was selected to substitute the nitroindazole core with 1,4-disubstituted triazole units after converting one of the N-(2-bromoethyl)nitroindazoles into the corresponding azide. The reactivity in 1,3-dipolar cycloaddition reactions with nitrile imines generated in situ from ethyl hydrazono-α-bromoglyoxylates was studied with nitroindazoles bearing a vinyl unit. The corresponding nitroindazole-pyrazoline derivatives were obtained in good to excellent yields.


Assuntos
Reação de Cicloadição , Pirazóis/síntese química , Triazóis/síntese química , Catálise , Estrutura Molecular , Pirazóis/química , Triazóis/química
14.
J Hazard Mater ; 370: 80-90, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29150138

RESUMO

The pollution of water resources due to the disposal of toxic heavy metals has been a growing global concern for the last decades. For this purpose, the search for effective and economic material based adsorbents is required, due to the efficiency of the process. In this work, a novel inorganic-organic hybrid material based on silica chemically modified with a porphyrin (SiNTPP), with a high metal removal efficiency, was developed. The new material was characterized using a set of suitable techniques such as 13C NMR of the solid state, elemental analysis, FTIR, nitrogen adsorption-desorption isotherm, BET surface area, BJH pore sizes and scanning electron microscopy (SEM). The new material surface exhibits good chemical and thermal stability based on the obtained thermogravimetric curves (TGA). An adsorption study was accomplished to investigate the effect of porphyrin-silica hybrid on the removal of Pb(II), Zn(II), Cd(II) and Cu(II) from aqueous solutions using a batch method. The effect of various parameters, such as initial metal concentration, pH, temperature, as well as the kinetics and thermodynamics for sorption on SiNTPP were investigated. The studies demonstrate that adsorption is fast, as proved by the equilibrium achievement within 25min. The metals removal from aqueous solution are better adapted to the Langmuir isotherm model than to the Freundlich model. The thermodynamic parameters (ΔG°, ΔH° and ΔS°) disclose that the process was endothermic and spontaneous in nature, and the adsorption process follows a pseudo-second order kinetics. The adsorbent can be regenerated continuously without affecting its extraction percentage. Its effectiveness is highly justified compared to previous described materials.

15.
Front Microbiol ; 9: 2665, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30510542

RESUMO

Antimicrobial photodynamic therapy (aPDT) is gaining a special importance as an effective approach against multidrug-resistant strains responsible of fatal infections. The addition of potassium iodide (KI), a non-toxic salt, is recognized to increase the aPDT efficiency of some photosensitizers (PSs) on a broad-spectrum of microorganisms. As the reported cases only refer positive aPDT potentiation results, in this work we selected a broad range of porphyrinic and non-porphyrinic PSs in order to gain a more comprehensive knowledge about this aPDT potentiation by KI. For this evaluation were selected a series of meso-tetraarylporphyrins positively charged at meso positions or at ß-pyrrolic positions and the non-porphyrinic dyes Methylene blue, Rose Bengal, Toluidine Blue O, Malachite Green and Crystal Violet; the assays were performed using a bioluminescent E. coli strain as a model. The results indicate that KI has also the ability to potentiate the aPDT process mediated by some of the cationic PSs [Tri-Py(+)-Me, Tetra-Py(+)-Me, Form, RB, MB, Mono-Py(+)-Me, ß-ImiPhTPP, ß-ImiPyTPP, and ß-BrImiPyTPP] allowing a drastic reduction of the treatment time as well as of the PS concentration. However, the efficacy of some porphyrinic and non-porphyrinic PSs [Di-Py(+)-Me opp , Di-Py(+)-Me adj , Tetra-Py, TBO, CV, and MG] was not improved by the presence of the coadjuvant. For the PSs tested in this study, the ones capable to decompose the peroxyiodide into iodine (easily detectable by spectroscopy or by the visual appearance of a blue color in the presence of amylose) were the most promising ones to be used in combination with KI. Although these studies confirmed that the generation of 1O2 is an important fact in this process, the PS structure (charge number and charge position), aggregation behavior and affinity for the cell membrane are also important features to be taken in account.

16.
ChemSusChem ; 11(16): 2681-2694, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-29975819

RESUMO

A green, template-free and easy-to-implement strategy was developed to access holey g-C3 N4 (GCN) nanosheets doped with carbon. The protocol involves heating dicyandiamide with ß-cyclodextrin (ßCD) prior to polymerization. The local symmetry of the GCN skeleton is broken, yielding CxGCN (x corresponds to the initial amount of ßCD used) with pores and a distorted structure. The electronic, emission, optical and textural properties of the best-performing material, C2GCN, were significantly modified as compared to bulk GCN. The spectroscopic and luminescent features of C2GCN show the characteristic π-π* electronic transition of GCN, accompanied by much stronger n-π* electronic transitions owing to the porous and distorted network. These new electronic transitions, along with the presence of additional carbon synergistically contributed to enhanced visible light absorption and restrained recombination of electron-hole pairs. Steady-state and time-resolved photoluminescence showed an effective quench of the fluorescence emission, accompanied by a decrease of fluorescence lifetime of C2GCN (2.20 ns) in comparison with GCN (5.85 ns), owing to the delocalization of electron and holes to new recombination centers. The photocatalytic activity of C2GCN was attributed to efficient charge carrier separation and improved visible-light absorbing ability. As result, C2GCN exhibited ∼5 times higher photocatalytic H2 generation under visible light than bulk GCN.

17.
J Org Chem ; 83(9): 5282-5287, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29644855

RESUMO

The synthesis of two triads with two porphyrinyl units linked by oligopyridine derivatives and a new ß-functionalized porphyrin-dihydroazepine is described. One of the porphyrin-oligopyridine triads has a quinquepyridine unit connecting the porphyrins ß-pyrrolic positions, while the other one has an asymmetric quaterpyridine with one of the pyridines fused to the porphyrin. All compounds have fluorescence emission quantum yields in the range of meso-tetraphenylporphyrin (16-22%).

18.
Molecules ; 23(4)2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29642601

RESUMO

In this work, the N-confused porphyrin 5,10,15,20-tetraphenyl-2-aza-21-carbaporphyrin (NCTPP) was immobilized on neutral or cationic supports based on silica and on Merrifield resin. The new materials were characterized by appropriate techniques (UV-Vis spectroscopy, SEM, and zeta potential analysis). Piezoelectric quartz crystal gold electrodes were coated with the different hybrids and their ability to interact with heavy metals was evaluated. The preliminary results obtained showed that the new materials can be explored for metal cations detection and the modification of the material surface is a key factor in tuning the metal selectivity.


Assuntos
Metais Pesados/análise , Porfirinas/química , Técnicas Biossensoriais , Eletrodos , Estrutura Molecular , Poliestirenos/química , Dióxido de Silício/química , Propriedades de Superfície
19.
ACS Omega ; 3(9): 11184-11191, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31459228

RESUMO

Telomerase inhibition has been an important strategy in cancer therapies, but for which effective drugs are still required. Here, noncovalent hybrid nanoplatforms containing the tetracationic 5,10,15,20-tetrakis(1-methyl-pyridinium-4-yl)porphyrin (TMPyP) and graphene oxide (GO) were prepared for promoting telomerase inhibition through the selective detection and stabilization of DNA guanine-quadruplex (G-Q) structures. Upon binding TMPyP to the GO sheets, the typical absorption bands of porphyrin have been red-shifted and the fluorescence emission was quenched. Raman mapping was used for the first time to provide new insights into the role of the electrostatic and π-π stacking interactions in the formation of such hybrids. The selective recovery of fluorescence observed during the titration of TMPyP@GO with G-Q, resembles a selective "turn-off-on" fluorescence sensor for the detection of G-Q, paving the way for a new class of antitumor drugs.

20.
Molecules ; 22(8)2017 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-28758915

RESUMO

Porphyrins bearing formyl or vinyl groups have been explored as starting materials to prepare new compounds with adequate features for different applications. In this review it is discussed mainly synthetic strategies based on the reaction of meso-tetraarylporphyrins bearing those groups at ß-pyrrolic positions. The use of some of the obtained porphyrin derivatives for further transformations, namely via pericyclic reactions, is also highlighted.


Assuntos
Porfirinas/química , Porfirinas/síntese química , Animais , Humanos
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