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Complexes of organotin compounds RSnCl with bisand trisphosphonate derivatives of 2,6-di- tert-butyl-4-methylphenol (ionol) were synthesized. X-ray diffraction studies were carried out for some of them. The redox properties of the synthesized compounds were characterized by cyclic voltammetry. Antioxidant/prooxidant activity of the complexes was studied using a new electrochemical method based on measuring the rate of hydrogen atom transfer to the stable radical 2,2´-diphenyl-1-picrylhydrazyl (DPPH). The data obtained were compared with the results of studying activity of the compounds during lipid peroxidation (LP) in biological samples. A correlation is observed between the results on antioxidant activity obtained by electrochemical DPPH test and using biological samples. Unlike the initial organotin compounds, the synthesized complexes have antioxidant activity, whereas phosphorus-containing phenols exhibit the properties of efficient antioxidants and chelating agents. [ABSTRACT FROM AUTHOR]

The article focuses on the synthesis of 10-vertex closo-nickelacarborane, metallacarborane catalysts and cage carbon atoms. Details regarding 11-vertex clusters, complex 1, radioactive isotopes, NMR spectroscopy, and ellipsoids are also mentioned. An overview of structural identification and polyhedral positions of 10-vertex closo-nickelacarborane are also offered.

A series of new 1-[4-(aminosulfonyl)phenyl]-5-oxopyrrolidine-3-carboxylic acids were synthesized by the solvent-free condensation of 4-aminobenzenesulfonamides with itaconic acid at 140–165 °C. The synthesized compounds were examined for antimicrobial activity. [ABSTRACT FROM AUTHOR]

commo-Ferracarboranes and [8-{(nido-7″,8″-C2B9H11-9″(11″)-)Ph2PCH2CH2PPh2}-commo-3,3′-Fe-{1,2-C2H9B10}{1′2′-C2B9H11}] were prepared as minor products in the metallation reaction of [K]+[nido-7,8-C2B9H12]− with the 14-electron iron complex [Ph2P(CH2)2PPh2]FeCl2. The structures of the complexes were determined by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

A series of new heterocyclic ensembles, derivatives of 5-oxo-1-(1,3,4-thiadiazol-2-yl)-pyrrolidine-3-carboxylic acid, was synthesized by heating 5-substituted 1,3,4-thiadiazol-2-amines and itaconic acid under solvent-free conditions or with the addition of acetic acid at 140–150 °C. The resulting acids can be used as building blocks in the synthesis of new potentially biologically active heterocyclic compounds. [ABSTRACT FROM AUTHOR]

New biologically active substances isolated from natural sources provide valuable information on structural motifs that are important for a specific type of activity and can also be used as drugs or serve as raw materials for chemical modification in order to develop new pharmaceuticals. This review considers natural antibiotics combining two pharmacophores in their structure: a redox-active naphthoquinone moiety and a membrane-active polyol macrolide. Data on their structures and the spectrum of biological activity are summarized. [ABSTRACT FROM AUTHOR]

Representatives of the new heterocyclic system, pyrimido[5’,4’:3,4]pyrrolo[1,2-f]phenanthridine, were obtained via the intramolecular C-H-arylation of 6-aryl-5-(2-bromophenyl) pyrrolo[3,4-d]pyrimidine-2,4-diones catalyzed by palladium complexes with N-heterocyclic carbene ligands (Pd/NHC). [ABSTRACT FROM AUTHOR]

Condensed pregnano[17,16-d]triazolines were produced in 1,3-dipolar cycloaddition of 16-dehydropregnenolone acetate with organic azides at 10 kbar. The structure of the synthesized compounds was determined by using two-dimensional NMR spectroscopy (1H—1H COSY, NOESY, HSQC, and HMBC). [ABSTRACT FROM AUTHOR]

New 3'-(4-chlorophenyl)-5',5'-dimethyl-2'-oxospiro[(2 H)-chromene-2,4'-1,3-oxazolidine] was synthesized to study the donor influence of the chlorine atom at the N-phenyl substituent on the structure and photochromic properties of 1,3-oxazolidine-containing spiropyrans. Photochemical properties of synthesized 1,3-oxazolidine derivatives were studied at room temperature in toluene. The X-ray diffraction parameters for the new compound were compared with the data obtained earlier for similar spiropyrans. [ABSTRACT FROM AUTHOR]

An approach to the synthesis of earlier unknown androstano[17,16-d]pyrazoles containing a monothiooxamide fragment at the nitrogen atom of the pyrazole ring has been suggested. The method is based on the reaction of NH-unsubstituted androstano[17,16-d]pyrazole with chloroacetyl chloride with subsequent involvement of the obtained N-chloroacetylpyrazole into the reaction with elementary sulfur in the presence of aromatic amines. The synthesized androstano[17,16-d]pyrazoles containing a monothiooxamide fragment at the nitrogen atom of the pyrazole ring exhibit high antiparasitic activity. [ABSTRACT FROM AUTHOR]