Structural Dynamics and Relaxation Processes with Participation of Excited Singlet and Triplet States in Sterically Hindered Porphyrins and Their Chemical Dimers

Abstract

Paper presents an overview of mutual Belarussian-Russian collaboration

Magnetic Circular Dichroism of meso-Phenyl-Substituted Pd-Octaethylporphyrins

“…According to the experimental data, 5 , 59 mono- and symmetrically (5,15Ph) di- meso -phenyl substituted β-alkylporphyrins (free bases) are planar, and correspondingly, the absorption and fluorescence properties are close to those characteristic of ordinary planar porphyrins. 60 As was shown previously 5 , 8 , 59 , 61 , 62 for free base β-alkyl-porphyrins, an increase in the number of bulky meso -phenyl substituents ( n > 2), which experience steric interactions with closely located peripheral β-alkyl groups, leads to spatial distortions of the tetrapyrrole macrocycle, considerably changing its geometric structure not only in the T 1 state but also in S 0 : Out-of-plane distortions of the π-conjugated tetrapyrrole macrocycle have been confirmed by NMR data. Computer modeling 61 , 63 shows that out-of-plane deformations of the porphyrin macrocycle for molecules of OEP-Ph type manifest themselves in the rotation of pyrrolic rings (flanking the phenyl ring) around the C α –C α axis.…”

Antitumor effects evaluation of a novel porphyrin derivative in photodynamic therapy

“…PDT has been regarded as a promising method for the treatment of various cancer and vascular proliferative diseases; developments of suitable photosensitizers (PSs) are highly desired to improve the prospect for the use of PDT [13]. While there is considerable attention in the synthesis of new PSs with improved PDT characteristics, porphyrin derivatives are particularly strong under investigations in preclinical and clinical PDT of tumors [14][15][16].…”

Deactivation of Excited States in Nanostructures Containing Cu-Porphyrin Subunit

“…In this paper, the subject of the discussion will be the dimers in which tetrapyrrolic subunits are covalently linked via spacers of various nature: i) ethane-bisporphyrins with a single -CH 2 -CH 2 -via meso-positions, [34,[61][62][63][64][65][66][67] ii) cyclodimers where cyclopentaneporphyrin molecules are coupled via isocycles, [68][69][70][71][72][73] and iii) chemical dimers of octaethylporphyrins with the phenyl bridge via meso-positions. [17,18,27,[74][75][76] It should be noted that in order to clarify spectral-kinetic properties that are characteristic for the dimers namely, we have especially prepared and characterized the precursor monomeric species with side substituents of the same nature and in the same positions like the corresponding spacers.…”

“…[54] First results of our group in this field have been obtained for mixed ethanebisporphyrins in [1983][1984]. [62,63,105] In the [17,18,27,[74][75][76] Me: H 2 , Zn and/or Cu.…”

“…[4][5][6][7][8][9] Correspondingly, a significant interest of numerous scientific groups is devoted to the design and investigation of biomimetic models based on tetrapyrrole compounds that fold or self-assemble predictably in order to form multicomponent well-defined arrays with effective energy transfer and charge separation like in photosynthetic objects in vivo. [10][11][12][13][14][15][16][17][18][19][20][21][22] On the other hand, there are many promising self-organized systems or nanoassemblies (including even organic-inorganic counterparts) which offer exciting opportunities for the engineering and preparation of various man-made molecular nanodevices in the modern fields of molecular electronics (photoinduced molecular switches, photonic wires, solar cells, optoelectronic gates, information storage, etc.) and nanobiophotonics (nanoprobes for biomedical imaging, biosensing and photodynamic therapy of cancer, etc).…”