ObjectiveTo synthesize novel inhibitors of the nuclear enzyme poly(adenosine 5′-diphosphate [ADP]-ribose) synthetase (PARS), also known as poly(ADP-ribose) polymerase (PARP), and to test them in in vitro models of oxidant-induced cytotoxicity and in endotoxin and splanchnic occlusion-reperfusion-ind

Novel phenanthridinone inhibitors of poly (adenosine 5'-diphosphate-ribose) synthetase: potent cytoprotective and antishock agents.

The present work is devoted to the study of a certain class of nonlocal evolution problem, in which we combine the Dirichlet boundary condition with the integral boundary condition. The study is based on a priori estimates of operator generated by the considered probems.

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République Algérienne Démocratique et Populaire Ministère de l'Enseignement Supérieur et de la Recherche Scientifique Université Mentouri - Constantine

Aromatic nucleophilic denitrocyclization reactions

An efficient palladium catalyzed C-H bond activation for the synthesis of benzo[c]chromen-6-ones using diazonium salts is described. In the presence of Pd(OAc)2, dppp, PivOH and K2CO3, the diazonium salt can be transformed into the product through a denitrogenation/C-H bond activation/cyclization sequence in acetonitrile. Altogether, nine structurally diverse substituted benzoLc]chromen-6-ones were prepared in excellent yields through two different methods.

https://journals.sagepub.com/doi/pdf/10.1177/1934578X1701200419

Syntheses of Benzo[c]Chromen-6-ones by Palladium Catalyzed C-H Bond Activation using Diazonium Salts

Synthesis and transformations of 3,8,10-trinitro-6H-dibenzo[b,d]pyran-6-one in DMSO and DMF

Treatment of 2,4,8,10-tetranitro-6(5H)-phenanthridinone with hexamethylphosphoric triamide leads to intermolecular nucleophilic substitution of the nitro group by a hydroxy group, the source of which is the water contained in the solvent, to give 10-hydroxy-2,4,8-trinitro-6(5H)-phenanthridinone. An intramolecular interaction with the participation of a proton of the aromatic ring and an oxygen atom of the hydroxy or acetoxy group of the 10-hydroxy- or 10-acetoxy-2,4,8,-trinitro-6(5H)-phenanthridinone, the properties of which are characteristic for an intramolecular hydrogen bond, was detected by x-ray diffraction analysis and PMR spectroscopy.

Synthesis and structures of 10-hydroxy- and 10-acetoxy-6(5H)phenanthridinones

The photoconductivity of vacuum evaporated thin films of fluorenone and its nitro-substituted derivatives is investigated. A substantial effect of the molecular structure on photoelectric properties is revealed. It is demonstrated that the increase of the number of nitro groups in the molecule leads to photosensitivity enhancement from 0.018 for nitrofluorenone to 0.60 for tetranitrofluorenone. The enhancement is caused by the increased probability of the electron-hole pair formation during the initial stage of photogeneration. The average radius for a thermalized pair decreases from 2.75 to 2.0 nm with the substitution. The activation energy of steady-state photoconductivity for the nitro derivatives coincides with the photogeneration activation energy calculated from the Onsager model.

Relationship between molecular structure and photoelectric properties in a series of nitro-substituted fluorenone derivatives

Methods for the preparation of nitro-substituted 6(5h)-phenanthridinones were examined. The nitration of 6(5H)-phenanthridinone, 5-methyl-6-(5H)- phenanthridinone, and 2-bromo-6(5H)-phenanthridinone was studied, and 2-, 3-, 4-nitro-, 2,4-, 2,8-, 4,8-dinitro-, 2,4,8-trinitro-, and 2,4,8,10-tetranitro-6(5H)-phenanthridinones, 2,4,8-trinitro- and 2,4,8,10-tetranitro-6-(5H)-phenanthridinones, and 2-bromo-4,8-dinitro- and 2-bromo-4,8,10-trinitro-6-(5H)-phenanthridinones were obtained. Proton magnetic resonance spectroscopy was used to identify the structure and predict the orientation of substitution in the nitration of 6(5H)-phenanthridinone and its nitro-substituted derivatives. The distribution of the electron density in these compounds was evaluated from an analysis of the chemical shifts of the protons.

Synthesis and structure of nitro-substituted 6(5H)-phenanthridinones

Methods for the synthesis of tri- and tetranitro-substituted 5,9-dioxo-4,5,9,10-tetrahydro-4,10-dioxapyrenes, 5,10-dioxo-4,5,9,10-tetrahydro-4,9-dioxapyrenes, and 6H-dibenzo[b,d]pyran-6-one were developed in a search for effective sensitizers for electrophotographic layers based on carbazole-containing polymers. The possibility of the production of nitro compounds that contain three vicinal nitro groups was demonstrated. Under severe nitration conditions 2,4,8-trinitro-6H-dibenzo[b,d]pyran-6-one is cleaved to give 2-hydroxy-2′-carboxy-3,5,4′-trinitro-biphenyl, which is resistant to cyclization to give the starting compound, evidently because of the existence of an intramolecular hydrogen bond between the hydroxy group and the nitro group.

A. N. Poplavskii

Papers

Synthesis and transformations of 3,8,10-trinitro-6H-dibenzo[b,d]pyran-6-one in DMSO and DMF

Synthesis and structures of 10-hydroxy- and 10-acetoxy-6(5H)phenanthridinones

Relationship between molecular structure and photoelectric properties in a series of nitro-substituted fluorenone derivatives

Synthesis and structure of nitro-substituted 6(5H)-phenanthridinones

Synthesis of nitro-substituted dioxotetrahydrodioxapyrenes and 6H-dibenzo[b,d]pyran-6-one