The reactions of isatins, 3-amino-1-pheyl-1H-pyrazol-5(4H)-one, and monocyclic ketones, have been developed for preparation spiro[indoline-3,4'-pyrazolo[3,4-b]quinoline]-2,3'(6'H)-dione, spiro[cyclohepta[b]pyrazolo[4,3-e]pyridine-4,3'-indoline]-2′,3-dione, spiro[cycloocta[b]pyrazolo[4,3-e]pyridine-4,3'-indoline]-2′,3(6H)-dione, spiro[cyclo dodeca[b]pyrazolo[4,3-e]pyridine-4,3'-indoline]-2′,3(6H...

In the last few years, imidazo[1,5-a]pyridine scaffolds and derivatives have attracted growing attention due to their unique chemical structure optical behaviors. this work, a series of pyridylimidazo[1,5-a]pyridine corresponding pyridinium salts were synthesized properties investigated evaluate effect quaternization on features both in solution polymeric matrix. A critical analysis based spect...

Recent advances in pyridine synthesis are described. Modification of traditional condensation strategies continues to be a recurrent theme in contemporary literature. Advancements in transition-metal-catalyzed cyclization and cross-coupling procedures offer new routes to functionalized pyridine derivatives. These recently developed methodologies are a valuable addition to azaheterocycle synthesis.

New denitrifying bacteria that could degrade pyridine under both aerobic and anaerobic conditions were isolated from industrial wastewater. The successful enrichment and isolation of these strains required selenite as a trace element. These isolates appeared to be closely related to Azoarcus species according to the results of 16S rRNA sequence analysis. An isolated strain, pF6, metabolized pyr...

The adsorption of pyridine onto silver colloids has been investigated by Raman spectroscopy experiments and by ab initio DFT and MP2 calculations. The solvation dynamics of the pyridine in water has been studied by a molecular dynamics simulation. The results are compared with the latest available experimental and theoretical data. It is found that the pyridine is essentially hydrogen bonded to...

Dacarbazine is an antitumor prodrug which is used for the treatment of malignant metastatic melanoma and Hodgkin’s disease. It requires initial activation in liver through an N-demethylationreaction. The active metabolite prevents the progress of disease via alkylation of guanine bases in DNA strands. In order to investigate the importance of imidazole ring and its dynamictautomerization in ant...

A series of Schiff Bases of Ni(II) and Cu(II) using acetylacetone (acac), salicylaldehyde (sal), ethylenediamine (en), and o-phenylendiarnine (dabe) were prepared and characterized. The electronic spectra of some copper chelates in various organic solvents depend strongly on the solvent used and the d-d band of Cu(II) shifts to red with the increase of the Donor Number (DN) of solvent. The ...

The cathodic polarographic wave observed for solutions of AlCl, in pyridine is due not to reduction of Al(III), but to reduction of the solvent, in which process Al(II1) plays an essential role, apparently by polarizing the pyridine through the formation of a Lewis acid-base adduct with the pyridine nitrogen. Macroscale electrolysis of pyridine solutions of AlCl, at a mercury cathode results in...

The title co-crystal, C(9)H(9)NO(2)·C(6)H(6)O(2), is composed of one 2,6-diacetyl-pyridine mol-ecule and one resorcinol mol-ecule as the asymmetric unit. In the 2,6-diacetyl-pyridine mol-ecule, the two carbonyl groups are anti-periplanar to the pyridine N atom. In the crystal, the 2,6-diacetyl-pyridine and resorcinol mol-ecules are connected by two O-H⋯O hydrogen bonds, forming planar chains of...

Polymer-supported oxidic osmium catalysts based on cross-linked poly(4-vinyl pyridine) were synthesized by various routes and characterized by a number of physical techniques (Raman, IR, XPS, “C and 15N solid-state NMR spectroscopy). Model compounds of type Os,O,L, (L = pyridine, 4-iso-propyl pyridine, and 4-tert-butyl pyridine) were obtained under the conditions of the catalyst synthesis. The ...