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New ditopic organic ligands with (pyridylmethylidene)imidazolone and pyridylbenzothi-azole moieties were synthesized by Cu-catalyzed azide-alkyne cycloaddition of 6-(prop-2-yn-1yloxy)-2-(pyridin-2-yl)benzothiazoleto3-azidoalkyl-5-[(Z-(pyridin-2-yl)methylidene]-2-(methylthio)dihydro-4H-imidazol-4-ones. The synthesized ligands (L) react with copper(ii) chloride to give coordination compounds of general formula LCuCl2 with coordination of the copper ion on the pyridylbenzothiazole fragment. [ABSTRACT FROM AUTHOR]

New type dispiroindolinones, dispiroimidazolidine-4,3′-pyrrolidine-2′,3″-indolinones unsubstituted at position 4′ of the central pyrrolidine ring, were synthesized by the 1,3-dipolar cycloaddition of azomethine ylides, generated from N-alkyl-substituted amino acids and isatines, to 5-methylidene-substituted 3-phenylhydantoin. [ABSTRACT FROM AUTHOR]

A method has been developed for the preparation of a new type of dispiro derivative, 5''-bromo-2-[(4-chlorophenyl)sulfanyl]-1'-methyl-1,4'-diphenyldispiro[imidazole-4,3'-pyrrolidine-2',3''-indoline]-2'',5(1H)-dione, starting from 2-thiohydantoin and using a 1,3-dipolar cycloaddition reaction. The configuration of the target dispiro derivative was unambiguously established by physicochemical methods. [ABSTRACT FROM AUTHOR]

Regioselective synthesis of new dispiro indolinones combining both an indolinone and an oxazolone fragment in their structure comprised the 1,3-dipolar cycloaddition of azomethine ylides, generated in situ from isatin and sarcosine, at 2-aryl-5-arylmethylidene-substituted 1,3-oxazol-5(4H)-ones. When ortho and para halogen atoms were present in the aromatic substituents of the starting oxazolones, complex mixtures containing large amounts of oxazoline ring opening products and their dispiro derivatives were formed. The cytotoxicity of compounds was tested by MTT on LNCaP, PC3, HCT116, MCF7, A549, HEK, and VA13 cell lines. The compound possessing the best cytotoxicity revealed the IC50 = 1.08±0.96 μM towards the p53- expressing LNCaP cells and lower activity (IC50 = 3.21±1.45 μM) towards the non-expressing p53 protein PC3 cells, however, it has proved inactive towards the HCT cells, both expressing (HCТ+/+) and non-expressing (HCT-/-) p53. [ABSTRACT FROM AUTHOR]

By six examples, it was demonstrated that nitrosylsulfuric acid can be successfully used for oxidation of 3,5-diaryl-4,5-dihydroisoxazoles to the corresponding 3,5-diarylisoxazoles. If the starting isoxazolines contain the aromatic substituents activated towards electrophilic substitution, nitration of both newly formed isoxazole and substituted benzene rings occurred. [ABSTRACT FROM AUTHOR]

Arylcyclopropanes react with nitrosyl chloride activated by sulfur(VI) oxide to give the corresponding 5-aryl-4,5-dihydro-1,2-oxazoles in quantitative yields. The complex NOC1·2SO3 is a highly efficient nitrosating agent which makes it possible to involve in the process arylcyclopropanes having both donor and acceptor substituents in the aromatic ring. [ABSTRACT FROM AUTHOR]

Arylcyclopropanes readily react with nitrosyl chloride in liquid sulfur dioxide to give the corresponding 5-aryl-4,5-dihydroisoxazoles in good yield. The reaction is most selective at -40 to -50°C; at higher temperature, the contribution of side processes becomes appreciable. The complete conversion of arylcyclopropanes containing donor substituents is attained with the use of 1.5 equiv of nitrosyl chloride, while the rate of the transformation of compounds with nonactivated aromatic rings considerably increases on raising the molar ratio NOCl-arylcyclopropane. [ABSTRACT FROM AUTHOR]