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2.
Eur J Mass Spectrom (Chichester) ; 17(3): 227-35, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21828414

RESUMO

The electron-ionization mass spectra (EI-MS) of oxo- and thio-derivatives of minor tobacco alkaloids and structurally similar piperidine alkaloids, i.e. thiocotinine (1), 2'-oxo-N-methylanabasine (2), 2'-thio-N- methylanabasine (3), 2'-oxoanabasamine (4) and 2'-thioanabasamine (5) are discussed and general fragmentation routes of their molecular cations are proposed. Comparison of the data obtained for 1 with the EI-MS data of metameric metabolites of nicotine: 3'-hydroxycotinine, (A) and 5'-hydroxycotinine, (B) allows a differentiation between these metamers. The data will be useful for the identification of metabolites of alkaloids of these types in biological matrices.


Assuntos
Alcaloides/análise , Alcaloides/química , Nicotiana/química , Extratos Vegetais/análise , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray/métodos
3.
Int J Anal Chem ; 2011: 652589, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21760788

RESUMO

The unpublished in the literature FAB mass spectral fragmentation of seven oxosparteines (i.e., 2-oxosparteine, 15-oxosparteine, 17-oxosparteine, 2,17-dioxosparteine, 2,13-dioxosparteine, 2-oxo-13-hydroxysparteine, and 2-oxo-17-hydroxysparteine) is investigated. Fragmentation pathways, elucidation of which was assisted by FAB/collision-induced dissociation (CID) mass spectra measurements, are discussed. The data obtained create the basis for distinguishing positional isomers.

4.
ISRN Org Chem ; 2011: 610521, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-24052828

RESUMO

Six new 2-o-(m- and p-)chlorobenzylthio-6-methyl-5-piperidino-(or morpholino-) methyluracils have been prepared. The structures of these compounds were confirmed by spectroscopic (FT-IR, UV-Vis, (1)H NMR, (13)C NMR, and HMBC) and elemental analyses. Estimation of pharmacotherapeutic potential has been made for synthesized compounds on the basis of prediction of activity spectra for substances (PASS).

5.
Eur J Mass Spectrom (Chichester) ; 16(2): 187-98, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20212328

RESUMO

Electron ionization (EI) mass spectral fragmentation of 2-thio-5-methylenecarboxy (5- methylenecarbonylalkoxy)uracils and their derivatives, five new 2-alkoxycarbonylalkylthio-5-methylenecarboxy (5- methylenecarbonylalkoxy)uracils and three new 3-oxo-thiazolo-[3,2-a]-pyrimidine-6-methylenecarbonylalkoxy-5-ones are investigated. Fragmentation pathways whose elucidation is assisted by accurate mass measurements and metastable transitions are established. The correlations between the abundances of the selected fragment ions and the molecular ions of investigated compounds are discussed. The data obtained create the basis for differentiating structural isomers and can be used for distinction of the compounds investigated from the series of 2- (or 4-) alkoxycarbonylalkylthiouracils, 2-alkoxycarbonylalkylthio-6-carboxyuracils and 1-alkoxycarbonylalkyluracils from their isomers and metamers.


Assuntos
Pirimidinonas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Tiazóis/química , Uracila/análogos & derivados , Uracila/química , Isomerismo
6.
Eur J Mass Spectrom (Chichester) ; 15(4): 487-95, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19661557

RESUMO

The electron ionization (EI) and fast atom bombardment (FAB) mass spectral fragmentations of ten copper(II) dichloride (dibromide, diformate, diacetate and dithiocyanate) complexes of (-)-sparteine and (-)-alpha-isosparteine were investigated. Fragmentation pathways, elucidation of which was assisted by accurate mass measurements and metastable transitions (EI-MS), as well as FAB/collision-induced dissociation (CID) mass spectral measurements are discussed. The data obtained create the basis for the differentiation of the ligand (sparteine or alpha-isosparteine) in the investigated complexes. The comparison of the results with those obtained previously for corresponding zinc(II) complexes forms the basis for the differentiation of metals in these compounds. The results show that both EI-MS and FAB-MS are very useful tools for the differentiation of ligands, as well as metals in the series of Zn(II) and Cu(II) dichloride (dibromide, diacetate, diformate, dithioacetate) complexes of (-)-sparteine and (-)-alpha-isosparteine.

7.
Eur J Mass Spectrom (Chichester) ; 15(4): 497-506, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19661558

RESUMO

Electron ionisation (EI) and fast atom bombardment (FAB) mass spectral fragmentations of nine 2,4-(and 2,1-) disubstituted o-(m- and p-)nitro-(chloro- and bromo-)-2-thiocytosinium halides are investigated. Fragmentation pathways, whose elucidation is assisted by accurate mass measurements and metastable transitions [EI-mass spectrometry (MS)], as well as FAB/collision-induced dissociation (CID) mass spectra measurements are discussed. The correlations between the abundances of the (C(11)H(10)N(4)SO(2))(+) 1-3; (C(11)H(10)N(3)SCl)(+) 4-6 and (C(11)H(10)N(3)SBr)(+) 7-9 ions and the selected fragment ions (EI- MS), as well as (C(18)H(16)N(5)SO(4))(+) 1-3; (C(18)H(16)N(3)SCl(2))(+) 4-6 and (C(18)H(16)N(3)SBr(2))(+) 7-9 ions and the selected ions (C(7)H(6)NO(2))(+) 1-3; (C(7)H(6)Cl)(+) 4-6; (C(7)H(6)Br)(+) 7-9 (FAB-MS) are discussed. The data obtained can be used for distinguishing isomers.


Assuntos
Hidrocarbonetos Halogenados/análise , Espectrometria de Massas de Bombardeamento Rápido de Átomos/métodos , Compostos de Benzil/análise , Compostos de Bromo/análise , Compostos Clorados/análise , Íons/química , Isomerismo , Nitrocompostos/análise , Espectrometria de Massa de Íon Secundário/métodos
9.
Eur J Med Chem ; 41(4): 519-25, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16516352

RESUMO

The synthesis of twenty-one new (E)-4-[piperidino-(4;-methylpiperidino-, morpholino-)N-alkoxy] stilbenes is reported. The compounds were tested for antimicrobial activities against Gram-negative, Gram-positive bacteria, and fungi. In particular, compounds 3b, 3c, 3f, 3g, 3h, 3k, 3l showed good antibacterial activity against Staphylococcus aureus and 3h, 3k, 3m, 3n also against Bacillus subtilis, as well as 3h, 3n also against Streptococcus faecalis.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Morfolinas/síntese química , Morfolinas/farmacologia , Estilbenos/síntese química , Estilbenos/farmacologia , Cromatografia em Camada Fina , Dimetil Sulfóxido , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Relação Estrutura-Atividade
13.
J Mass Spectrom ; 39(5): 541-7, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15170750

RESUMO

The mass spectral fragmentations of 2-cyano-2-methylsparteine (1), 2-cyano-2-phenylsparteine (2), 2-cyano-2-(p-tolyl)sparteine (3), 17-cyanosparteine (4) and 17-cyanolupanine (5) were investigated. Fragmentation pathways, whose identification was assisted by accurate mass measurements and a correlation between the abundances of the M(+*) and the selected fragment ions of the investigated compounds, are discussed. The data obtained create the basis for distinguishing the structural metamers.

15.
Farmaco ; 57(8): 657-61, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12361233

RESUMO

Twelve new N-substituted (E)-azachalconium bromides were synthesized and tested for antimicrobial and antifungal activities. Compounds 5c, 5d and 5h-5l showed very good antimicrobial activity against Staphylococcus aureus, Enterococcusfaecalis as well as Bacillus subtilis and 5h-5j showed moderate activity against Escherichia coli. In particular, (E)-N-dodecyl-4-azachalconium bromide (5i) and (E)-N-tetradecyl-4-azachalconium bromide (5j) showed the most intensive activity against all tested microorganisms.


Assuntos
Anti-Infecciosos , Compostos Aza/química , Compostos Aza/farmacologia , Brometos/química , Brometos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia
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