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Combined viral and photodynamic therapy for oncological diseases has great potential to treat aggressive tumors such as glioblastomas. A conjugate of vesicular stomatitis virus (VSV) with protoporphyrin IX was prepared, and its oncolytic effects were studied and compared to the effects of the individual components. The VSV showed an oncolytic effect on glioblastoma cell lines T98G and LN229 at a virus titer of 105 TCID50/mL. A VSV titer of 104 TCID50/mL was sufficient for neuroblastoma cell death. A study of the effect of VSV in tumor 3D cell modeling found that VSV had a clear viral cytopathic effect on spheroids of T98G and LN229 cells. Conjugation with the porphyrin significantly reduced the viral titer, but when irradiated, lysis of cells was observed. Photodynamic treatment of T98G and LN229 cells and spheroids with protoporphyrin IX as a photosensitizer also had a cytotoxic effect on cells and, to a lesser extent, on the tumoroids, as complete cell death was not achieved for the tumoroids. The combination therapy, which involved sequential photodynamic therapy using protoporphyrin IX as a photosensitizer and treatment with VSV, was shown to significantly enhance efficacy, resulting in complete cell death of both T98G and LN229 cells and tumoroids. The combination treatment allowed for the use of a lower viral titer (103–104 TCID50/mL) and a lower porphyrin concentration (0.5 μg/mL) to achieve a significant cytotoxic effect. As a result, the implementation of this combination therapy would likely lead to fewer side effects from the treatment. This study clearly demonstrated the excellent perspectives of combination therapy for the treatment of highly aggressive tumors such as glioblastomas. [ABSTRACT FROM AUTHOR]

Conjugated porphyrin dyads have valuable electron-optical properties that make them useful for a variety of applications. Two dyads of palladium(II) β-octaethylporphyrin linked with a butenyne bridge to nickel(II) meso-diphenylporphyrin and methyl pyropheophorbide-a were synthesized using the Sonogashira cross-coupling reaction. Both dyads exhibited optical properties considerably different from their corresponding components, which indicated strong electronic interaction between the units in the dyads in both the ground and excited states, providing fast energy flow between the chromophores. DFT calculations revealed the structural features of the dyads in interconnection with their electronic properties. Conjugation energy gain forced a decrease in the dihedral angle between the porphyrin plane and the linking carbon–carbon double bond, although at the expense of distortion of the diphenylporphyrin ring. Electron transitions upon excitation comprise molecular orbitals centered on both chromophores, and their interaction led to an emerging new bathochromically shifted Soret band component at 460 nm. The palladium porphyrinate–chlorin dyad exhibits luminescence properties in the red visible range at room temperature and phosphorescence in the near-infrared (NIR) range at 77 K. In contrast, the palladium–nickel porphyrinate dyad does not emit light but absorbs light more efficiently across the entire visible spectrum. Both dyads feature broad and strong absorption representing panchromatic-like dyes. These dyads could be useful as potential photosensitizers for solar light conversion devices. [ABSTRACT FROM AUTHOR]

A series of diamidophosphite ligands of various structures and denticities were synthesized from (11S,12S)-bis(hydroxymethyl)-9,10-dihydro-9,10-ethanoanthracene as a "roof shaped" 1,4-diol. On the basis of these ligands, we obtained three types of Pd(II) allylic complexes: a P,P-chelate, a P,S-bridged head-to-tail dinuclear complex, and complexes each containing a pair of P-monodentately coordinated P-, P,N- or P,S-ligands. The structures of the ligands and their complexes were determined using 2D NMR spectroscopy. Four diamidophosphites were also characterized via their X-ray structural data. This kind of stereoselector exhibited up to 98% ee in the Pd-mediated allylic substitution of (E)-1,3-diphenylallyl acetate with C- and N-nucleophiles. In the Pd-catalyzed allylic alkylation of cinnamyl acetate with various C-nucleophiles, ee values of up to 90% were obtained. In addition, up to 71% ee was achieved in the Pd-catalyzed asymmetric amination of 2-(diethoxyphosphoryl)-1-phenylallyl acetate with aniline, which is a pioneering example of diamidophosphite-type ligand involvement in this challenging reaction. The effects of the diamidophosphite moiety and the denticity of the ligands on the catalytic activity and enantioselectivity were investigated. [ABSTRACT FROM AUTHOR]

The meso‐imino derivatives of the palladium (II) and nickel (II) complexes of coproporphyrins I and II and β‐octaethylporphyrin were obtained by the Vilsmeier formylation followed by interaction with amines. The metal complexes of the azomethines obtained were transformed to the corresponding complexes of cyclopentane and cyclopentane‐pyrrolidone fused porphyrin derivatives by thermolysis. The plausible mechanism of such transformations was suggested and substantiated with quantum chemical calculations. Meso‐cyano‐, meso‐hydroxy‐, and meso‐aminocarbonyl derivatives of β‐octaethylporphyrin were obtained by treatment of the corresponding meso‐imino derivatives with bases. Demetalation of the nickel complex of the meso‐ hydroxy‐β‐octaethylporphyrin led to formation of the free base derivative. The structures of new types of the porphyrin derivatives were determined via X‐ray powder diffraction analysis. The obtained types of porphyrins are promising candidates to use as photosensitizers in medicine applications due to their longer wave absorption combined with high stability. New types of meso‐functionalization of porpyrins through formylation, Schiff base formation followed by thermal annulation or base treatment leading to cyclopentane‐condensed or meso‐cyano‐, meso‐amido‐, and meso‐hydroxy‐porphyrins. [ABSTRACT FROM AUTHOR]

A recyclable and effective polymer-immobilized ligandless palladium catalyst for the Suzuki reaction has been investigated. Palladium nanoparticles are formed in situ and stabilized by poly( N-vinylimidazole- co- N-vinylcaprolactam). A series of aryl bromides have been studied in the reaction with phenylboronic acid under mild conditions with water-alcohol systems as a solvent that complies with 'Green Chemistry' demands. The catalyst can be recycled eight times without appreciable loss in activity and a low degree of palladium leaching. Kinetic studies reveal unusual behavior of the reaction; this can be explained on the basis of the observation of changes to the sizes of the particles during recycling, as determined by TEM results. The suggested mechanism of the reaction is in accordance with the concept of the role of leaching in the process. [ABSTRACT FROM AUTHOR]

New complexes of neptunyl(V) isothiocyanate with 4'-aryl-substituted 2,2':6',2″-terpyridines (Terpy) and N , N -dimethylacetamide (DMA) were obtained: [(NpO 2 )(4'-Ph-Terpy)(DMA)(NCS)]·DMA, [(NpO 2 )(4'-(4-(CF 3 )C 6 H 4 )-Terpy)(DMA)(NCS)]·2H 2 O·DMA, [(NpO 2 )(4'-(3-BrC 6 H 4 )-Terpy)(DMA)(NCS)]·DMA, and [(NpO 2 )(4'-(2-(COOH)C 6 H 4 )-Terpy)(DMA)(NCS)]·DMA. The structures of the compounds were determined with X-ray diffraction analysis. The neptunium coordination polyhedra were found to be pentagonal bipyramids with O atoms of the NpO 2 groups in the apical positions and the equatorial planes formed by three N atoms of the terpyridine ligand, a N atom of the isothiocyanate anion, and an O atom of DMA. The influence of the substituents of the Ar group on the crystal structure is discussed. The IR spectra contain well-resolved bands of characteristic vibrations of all groups in the complex. The electronic absorption spectra are typical for neptunium(V) complexes and contain an intense narrow absorption band belonging to an f-f transition with a maximum of 988 nm and several long-wave satellites of lower intensity. The substituted terpyridines were shown to be efficient for the extraction of various valence forms of neptunium from the isothiocyanate solutions.