- Sequential Protonation of meso-(p-(Dimethylamino)phenyl)porphyrins: Charge-Transfer Excited States Producing Hyperporphyrins
-
Successive protonation by trifluoroacetic acid of meso-tetraphenylporphyrin derivatives bearing one, two or four p-dimethylamino groups gives rise to new types of spectra.With one free amino group, the spectrum of the centrally protonated porphyrin shows a strong far-red band, a broad, flat absorption in the visible, and a less intense Soret band.With two or more free amino groups, the Soret band of the centrally protonated porphyrin is further split into two components.Complete protonation, including the peripheral amino groups, in all cases restores the spectral structure of the unsubstituted tetraphenylporphyrin dication.The spectra of the dianions of tetraanilino- and tetraphenylporphyrins are also similar.These results, and the related behavior of p-oxyphenylporphyrins and protonated Schiff base porphyrins, lead to a general interpretation of hyperporphyrin spectra in terms of charge-transfer excited states, involving charge movement either into or out of the porphyrin ring.
- Ojadi, Emmanuel C. A.,Linschitz, Henry,Gouterman, Martin,Walter, Robert I.,Lindsey, Jonathan S.,et al.
-
-
Read Online
- Synthesis of tetraphenylporphins with reactive groups in the phenyl rings. 7. Salts of tetrakis(N,N,N-trimethylaminophenyl)porphins
-
Tetrakis(N,N-dimethylaminophenyl)porphins and water-soluble salts of tetrakis(N,N,N-tnmelhylaminophenyl)porphins have been obtained by the alkylation of tetrakis(aminophenyl)porphins with methyl iodide. 1996 Plenum Publishing Corporation.
- Syrbu,Semeikin,Syrbu
-
-
Read Online
- Docking studies, antitumor and antioxidant evaluation of newly synthesized porphyrin and metalloporphyrin derivatives
-
In this work, we have synthesized a series of novel porphyrin derivatives, 1–5, in high yields. The metal complexes of two of the newly synthesized porphyrin derivatives, 1a–d and 2a–d, have also been synthesized in high yields and characterized. In the synthesis of the new porphyrins and metalloporphrins, we employed our reported strategy in which we utilized N,N-dimethylformamide (DMF) as a capping agent in the reaction of pyrrole with different hetero-aryl aldehydes. The new porphyrin derivatives are equipped with different aromatic substituents and hetero-cycles at the peripheral position. The structures of the new compounds were confirmed by elemental and spectral analyses. The geometry and magnetic properties of the new metalloporphyrins 1a–d and 2a–d have also been studied. Antioxidant and cytotoxic activities of the new compounds were evaluated and structure-activity relationships were performed. Porphyrin derivatives 2a and 4 showed exceptional antioxidant activity compared to ascorbic acid as a reference. While the derivatives 2, 3, and 5 exhibited very strong cytotoxic activity against two human cell lines, HePG-2 and MCF-7. Docking for the most promising antioxidant porphyrins, 2a and 4, into the binding active site of antioxidant protein Human Peroxiredoxin (code: 1HD2) has been carried out to detect the degree of recognition antioxidant activity. Molecular docking of the most cytotoxic active porphyrins, 3 and 5, into the biding site of telomerase inhibitor enzyme has been carried out to assess the degree of recognition cytotoxic activity.
- Abou-Zeid, Laila,Ahmed, Asmaa,El-Asmy, Hala A.,Fadda, Ahmed A.,Omar, Walaa A. E.
-
-
- Porphyrin supramolecular arrays formed by weakly interacting meso-functional groups on Au(111)
-
The formation of a binary porphyrinic self-assembled system between meso-tetrakis(4-carboxyphenyl) porphyrin (TCPP) and meso-tetrakis(4-dimethyl amino) porphyrin (TDAP) was easily designed through non-covalent interactions in solution and adsorbed on a gold substrate. It was found that non-covalent interactions and geometrical conformations between porphyrins allow their self-assembly into a well-defined arrangement, which was confirmed by UV-Vis spectroscopy, electrochemistry, atomic force microscopy and density functional theory (DFT) studies.
- Sánchez-Mu?oz, Esteban,Gárate-Morales, José L.,Sandoval-Lira, Jacinto,Hernández-Pérez, Julio M.,Aguilar-Sánchez, Rocío
-
-
- Palladium(II) tetrakis(4-N,N,N-trimethylammoniumphenylene)porphyrin supported on ion-exchange resins as efficient and reusable catalysts for C-C coupling reactions
-
In this research, the Heck and Suzuki reactions catalyzed by tetrakis(4-N,N,N-trimethylammoniumphenylene)porphyrinatopalladium(II) iodide, [Pd(TTMAPP)]I4, immobilized on ion-exchange resins such as Dowex 50 WX8 and Amberlite IR-120 are reported. In this manner, first, tetrakis(4-N,N-dimethylaminophenylene)porphyrin was converted to tetrakis(4-N,N,N-trimethylammoniumphenylene)porphyrin iodide, [H 2TTMAPP]I4, with methyl iodide. Then this water soluble porphyrin was metalated by palladium(II) chloride and the [Pd(TTMAPP)]I 4 was produced. This cationic palladium porphyrin was immobilized onto the ionic supports via electrostatic interactions. The catalysts, [Pd(TTMAPP)]@Dowex 50 WX8 and [Pd(TTMAPP)]@Amberlit IR-120, were characterized by FT-IR and diffuse reflectance UV-Vis spectroscopic methods, and scanning electron microscopy. These heterogeneous catalysts are thermally stable, oxygen insensitive, phosphine-free, air- and moisture-stable in the C-C coupling reactions and are reusable several times without significant loss of their catalytic activity.
- Sadegh, Faranak,Bagheri, Omid,Moghadam, Majid,Mirkhani, Valiollah,Tangestaninejad, Shahram,Mohammadpoor-Baltork, Iraj
-
-
- Synthesis and pharmacological screening of novel meso-substituted porphyrin analogs
-
A novel series of mesotetrakis[aryl]-21H,23H-porphyrin derivatives 2a-j was synthesized from the condensation of aldehyde derivatives 1a-j with pyrrole in the presence of p-toluenesulfonic acid. The synthesized porphyrins were considered as a model to stu
- Fadda, Ahmed A.,El-Mekawy, Rasha E.,El-Shafei, Ahmed I.,Freeman, Harold
-
-
- Unusual Spectral Properties of meso-(N,N'-Dialkylaminophenyl)porphyrins
-
The behaviour of the porphyrins meso-tetrakis(4'-dialkylaminophenyl)porphyrin and 5,15-bis(4'-dimethylaminophenyl)-2,8,12,18-tetraethyl-3,7,13,17-tetramethylporphyrin in acidic solution is examined by ultraviolet-visible and 1H n.m.r. spectroscopy.The unu
- Gunter, Maxwell J.,Robinson, Byron C.
-
p. 1897 - 1905
(2007/10/02)
-