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1.
Bioorg Khim ; 39(2): 206-11, 2013.
Artigo em Russo | MEDLINE | ID: mdl-23964521

RESUMO

The reaction of betulonic acid chloride with 4-amino-2,2,6,6-tetramethylpeperidine-1-oxyl, 3-amino-2,2,5,5-tetramethylpyrrolidine-1-oxyl and 3-aminomethyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl gave corresponding triterpenoid amides. It was found that new derivatives exhibit cytotoxic activity against tumor cells CEM-13, U-937, MT-4. CCID50 value for most activity compound--N-[3-oxolup-20(29)-en-30-yl]-(2,2,6,6-tetramethylpiperidine-4-yl)-1-oxyl--was 5.7-33.1 microM.


Assuntos
Amidas/síntese química , Ácido Oleanólico/análogos & derivados , Terpenos/síntese química , Amidas/química , Amidas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Ácido Oleanólico/síntese química , Ácido Oleanólico/química , Ácido Oleanólico/farmacologia , Marcadores de Spin , Terpenos/química , Terpenos/farmacologia
2.
Bioorg Khim ; 38(1): 127-36, 2012.
Artigo em Russo | MEDLINE | ID: mdl-22792716

RESUMO

Condensation of methyl 16-aminomethyllambertianate with N-Boc-omega-amino acids leads smoothly to 16-(N-Boc-aminononan)- and 16-(N-Boc-aminoundecan)amidomethyllabdanoids. The amide of bicyclo[2.2.1]heptan-1,2-dicarbocylic acid with a labdanoid substituent was obtained under the reaction of methyl aminomethyllambertianate with bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic anhydride. Intereaction of methyl 16-aminomethyllambertianate with chloroacetyl chloride leads to methyl 16-(chloroacetylaminomethyl)lambertianate; condensation of this compound with amino acid methyl ethers the corresponding amides of methyl lambertianate was obtained. The resulting compounds are more (compared with lambertianic acid) cytotoxicity in the cell lines CEM-13, MT-4 and U-937 with an CCID50 concentration of 3.9-9.9 microM.


Assuntos
Citotoxinas , Diterpenos , Citotoxinas/síntese química , Citotoxinas/química , Citotoxinas/farmacologia , Diterpenos/síntese química , Diterpenos/química , Diterpenos/farmacologia , Relação Dose-Resposta a Droga , Humanos , Células U937
3.
Bioorg Khim ; 31(4): 372-84, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16119456

RESUMO

Photoactivatable derivatives Ar-NH-(CH2)n-NHpppB (where Ar = p-azidophenyl (A1), 5-azido-2-nitrobenzoyl (A2), or 4-azido-2,3,5,6-tetrafluorobenzoyl (A3) group; B = Ado or Guo; n = 2, 3, or 4) were synthesized. The phosphoroamidate bond stability was found to depend on the structure of both the heterocyclic and the photoactivatable groups. The derivative with A3, Ado, and n=3 is hydrolyzed with regeneration of aryl azide and ATP, whereas the other derivatives are stable in aqueous solutions. The photoanalogues with A1 and A2, B = Ado, and n = 2 or 4 were found to behave as initiating substrates toward the RNA polymerase II from Saccharomyces cerevisiae under the conditions of specific transcription initiation and control of the adenovirus late promoter. The photolysis of N-(4-azidophenyl)-1,4-diaminobutane and N-(5-azido-2-nitrobenzoyl)-1,3-diaminopropane, two functional fragments of the photoaffinity reagents, in aqueous solutions was established to result in the formation of p-benzoquinone diimine and p-nitro-N-arylhydroxylamine derivatives, respectively. The arylhydroxylamine derivatives undergo a number of transformations in aqueous solution leading to nitroso derivatives. We concluded that it is these nitroso derivatives (products of nitrene transformation, rather than the nitrene itself) that may modify proteins with reagents containing p-nitrophenylazide fragment.


Assuntos
Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/síntese química , Azidas/química , RNA Polimerase II/química , Eletroforese em Gel de Poliacrilamida , Hidroxilaminas/química , Estrutura Molecular , Marcadores de Fotoafinidade , Fotoquímica , RNA Polimerase II/metabolismo , Saccharomyces cerevisiae/enzimologia , Especificidade por Substrato
4.
Prikl Biokhim Mikrobiol ; 41(1): 107-12, 2005.
Artigo em Russo | MEDLINE | ID: mdl-15810741

RESUMO

Qualitative and quantitative compositions of extracts of birch (Betula pendula Roth.) leaves after natural and artificial defoliations were studied. Composition of the fraction of total lipids was determined. Overall, 11 fatty acids were identified. Differences between the fatty acid compositions of total lipids in the trees subjected to defoliation, consisting in the increase in quantities of short-chain saturated fatty acids and trienoic acids, were detected. Nine individual compounds--six flavones, two flavanones, and one flavanonol--were isolated from the flavonoid fraction by column chromatography. It was found that the total content of extractive substances in birch leaves as well as amounts of free sterols, triterpene compounds, and flavones decreased 1 year after an artificial defoliation and 1 month after depredation of 75% of birch stands by gypsy moth. On the contrary, the contents of flavanones and flavanonol increased. The assay method proposed may be used for studying the compositions of plant extracts.


Assuntos
Betula/química , Extratos Vegetais/química , Folhas de Planta/química , Ácidos Graxos/análise , Flavonoides/análise , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
5.
Nucleosides Nucleotides Nucleic Acids ; 23(6-7): 921-5, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15560082

RESUMO

Photoanlogues of the initiation substrates of the RNA polymerase II, N3ArNH(CH2)(n)NHpppA where N3Ar is 5-azido-2-nitrobenzoyl group (n = 2 or 4) were synthesized, allowing the preparation of photoreactive oligonucleotides in situ by RNA polymerase II for application as photolabels. Photolysis of p-nitro-substituted aromatic azide in aqueous medium was investigated. Using the azoxy-coupling reaction it was possible to determine whether a nitrene or p-nitrophenyl hydroxylamine azoxy compound is the trappable intermediate that is generated at ambient temperature in aqueous solution.


Assuntos
Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/química , Azidas/química , Hidroxilaminas/química , RNA Polimerase II/antagonistas & inibidores , Autorradiografia , Eletroforese em Gel de Poliacrilamida , Fotoquímica , RNA Polimerase II/metabolismo , Especificidade por Substrato
7.
J Photochem Photobiol B ; 65(1): 39-46, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11748004

RESUMO

p-Azidophenyl phosphate (I) has been exposed to ultraviolet light (lambda=313 nm) in aqueous solution with or without Lys. Analysis of the photoproducts by means of UV-VIS, IR, (1)H, (13)C and (31)P NMR spectroscopy has revealed that under irradiation of I inorganic phosphate (P(i)) is released, and p-benzoquinone monoimine (II) and p-benzoquinone (III) have appeared. The electrophilic nature of the intermediate results in a high tendency to react with lysine molecules, whereas the reaction with water is less favourable when I is irradiated in the presence of Lys. The product formed in this case is a phosphoramidate whose structure has been tentatively supported by (31)P NMR spectroscopy. These results imply that a p-azidophenyl phosphate is a highly potent aryl nitrene-precursor, which can be transformed easily into p-benzoquinone monoimine and is able to phosphorylate nucleophilic groups of amino acids. This finding is of great importance for the discussions about the chemical nature of protein photomodification products when p-azidophenyl phosphate derivatives are used as modifying reagents.


Assuntos
Benzoquinonas/química , Iminas/química , Organofosfatos/química , Concentração de Íons de Hidrogênio , Lisina/química , Estrutura Molecular , Fosforilação , Soluções
8.
J Photochem Photobiol B ; 61(1-2): 68-77, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11485850

RESUMO

Irradiation of a complex between N-(5-azido-2-nitrobenzoyl)-N'-(D-biotinyl)-1,2-diaminoethane (I) and streptavidin with light of 313 nm led to the covalent attachment of the photobiotin analogue I to the protein. Streptavidin could also be labelled in the dark with prephotolyzed I. These results indicate that a long-lived reactive intermediate was formed upon irradiation. Moreover, after cleavage of labelled streptavidin with proteinase K this intermediate appears to be covalently attached to the same peptide as the one obtained by direct photoaffinity labelling. An iminosulfurane II derived from the reaction of biotin sulfur atom with aryl nitrene is responsible for the dark-labelling reaction. The photoproduct II converts in an aqueous solution almost completely into N-(5-amino-2-nitrobenzoyl)-N'-(D-(S-oxo)biotinyl)-1,2-diaminoethane (the half-life of II is 10 days).


Assuntos
Biotina/análogos & derivados , Biotina/química , Indicadores e Reagentes/química , Nitrobenzoatos/química , Estreptavidina/química , Estrutura Molecular , Fotoquímica , Fotólise , Fatores de Tempo , Raios Ultravioleta
9.
Chem Commun (Camb) ; (18): 1774-5, 2001 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-12240309

RESUMO

Previously unknown 1,2,4,3,5-benzotrithiadiazepine 1 was prepared by 1:1 condensation of Ph-N=S=N-SiMe3 with S2Cl2 followed by intramolecular ortho-cyclization of [Ph-N=S=N-S-S-Cl] intermediate, and hydrolyzed in pyridine to unusual macrocyclic 7H,14H-dibenzo[d,i][1,2,6,7,3,8]tetrathiadiazecine 2.

10.
Inorg Chem ; 39(18): 3999-4005, 2000 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-11198853

RESUMO

TAS+ salts (TAS = (Me2N)3S) of the sulfur diimide anions Me3XNSN- (X = C (1a), Si (1b)) were prepared by Si-N bond cleavage from the corresponding sulfur diimides Me3XNSNSiMe3 and TAS-fluoride ((Me2N)3S+Me3SiF2-) and characterized by X-ray crystallography and multinuclear NMR spectroscopy. According to the experimentally determined bond lengths and theoretical calculations, the Me3XNSN- anions are best described as thiazylamides Me3X-N-S identical to N rather than sulfur diimides Me3X-N=S=N. In agreement with the calculated and experimentally determined structures of the isoelectronic thionylimides RNSO, 1a adopts the Z-configuration, which is electronically favored due to anomeric effects. The electronically disfavored E-configuration of 1b in the solid state can be explained by weak anion-cation interaction.

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