Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Eur J Med Chem ; 86: 291-309, 2014 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-25173828

RESUMO

New series of polysubstituted (2SR,4RS)-2-heteroaryltetrahydro-1,4-epoxy-1-benzazepines and cis-2-heteroaryl-4-hydroxytetrahydro-1H-1-benzazepines were designed and synthesized in moderate to high yields using a three-step procedure from ortho-allylanilines. Their antiparasitic activity was evaluated against the extracellular and intracellular forms of Trypanosoma cruzi and Leishmania (Leishmania) infantum parasites. Their cytotoxicity was also determined on Vero and THP-1 mammalian cells. Many of the tested compounds inhibited significantly the growth of extracellular forms of T. cruzi and L. (L.) infantum without showing cytotoxicity on Vero and HTP-1 cells. Only compounds 10h and 14f demonstrated good activity against amastigotes of T. cruzi, but none was able to inhibit the growth of L. (L.) infantum amastigotes.


Assuntos
Antiparasitários/síntese química , Antiparasitários/farmacologia , Benzazepinas/síntese química , Benzazepinas/farmacologia , Leishmania infantum/efeitos dos fármacos , Trypanosoma cruzi/efeitos dos fármacos , Animais , Antiparasitários/química , Benzazepinas/química , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Estrutura Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Células Vero
2.
Protein J ; 32(2): 118-25, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23381689

RESUMO

Understanding of protein-urea interactions is one of the greatest challenges to modern structural protein chemistry. Based in enzyme kinetics experiments and (1)H NMR spectroscopic analysis we proposed that urea, at low concentrations, directly interacts with the protonated histidines of the active center of RNase A, following a simple model of competitive inhibition. These results were supported by theoretical analysis based on the frontier molecular orbital theory and suggest that urea might establish a favorable interaction with the cationic amino acids. Our experimental evidence and theoretical analysis indicate that the initials steps of the molecular mechanism of Urea-RNase A interaction passes through the establishment of a three center four electron adduct. Also, our results would explain the observed disruption of the (1)H NMR signals corresponding to H12 and H119 (involved in catalysis) of the RNase A studied in the presence of urea. Our interaction model of urea-amino acids (cationic) can be extended to explain the inactivation of other enzymes with cationic amino acids at the active site.


Assuntos
Ribonuclease Pancreático/química , Ureia/química , Animais , Biocatálise , Bovinos , Cinética , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Desnaturação Proteica
3.
Nat Prod Commun ; 8(12): 1731-2, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24555284

RESUMO

From the aerial parts of Hypericum laricifolium Juss., twelve compounds were isolated and identified. They were the xanthones: 1-hydroxy-7-methoxy-xanthone (1), 1,7-dihydroxy-xanthone (2), 2-hydroxy-xanthone (3), 6-deoxyisojacareubin (4), 1,3-dihydroxy-6-methoxy-xanthone (6), and 1,5,6-trihydroxy-7-methoxy-xanthone (7), together with beta-sitosterol, betulinic acid, vanillic acid, isoquercitrin and a mixture of quercetin and isorhamnetin. All the compounds were characterized by spectroscopic and mass spectrometric methods, and by comparison with literature data. Thisis the first report on the presence of xanthones in H.laricifolium. 1,3-Dihydroxy-6-methoxy-xanthone has been previously synthesized, but this is the first report of its isolation from a natural source.


Assuntos
Hypericum/química , Xantonas/isolamento & purificação , Componentes Aéreos da Planta/química
4.
Bioorg Med Chem ; 18(13): 4721-39, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20627590

RESUMO

Forty six new 1,4-epoxy-2-exo-aryl- and cis-2-aryl-4-hydroxytetrahydro-1-benzazepine derivatives were synthesized and fully characterized. All compounds were tested in vitro against both Trypanosoma cruzi and Leishmania chagasi parasites and also for cytotoxicity using Vero and THP-1 mammalian cell lines. Many of the evaluated compounds showed remarkable activity against the epimastigote and intracellular amastigote forms of T. cruzi, with IC50 values comparable with that of control drug nifurtimox, a nitrofuran derivative currently used in the treatment of Chagas' disease. Other derivatives were found to have good activity against L. chagasi promastigotes, with low toxicity against the mammalian cells, but neither of them was active on intracellular amastigotes of L. chagasi infecting THP-1 macrophages.


Assuntos
Antiprotozoários/síntese química , Benzazepinas/química , Leishmania donovani/efeitos dos fármacos , Trypanosoma cruzi/efeitos dos fármacos , Animais , Antiprotozoários/uso terapêutico , Antiprotozoários/toxicidade , Benzazepinas/uso terapêutico , Benzazepinas/toxicidade , Linhagem Celular , Doença de Chagas/tratamento farmacológico , Humanos , Espectroscopia de Ressonância Magnética , Conformação Molecular
5.
Acta Crystallogr C ; 66(Pt 6): o284-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20522946

RESUMO

5-Acetyl-2-chloro-8,11-dimethyl-5,6,11,12-tetrahydrodibenzo[b,f]azocine, C(19)H(20)ClNO, (I), crystallizes as a single fully ordered isomer, but 14-acetyl-8,11-dimethyl-7,8,13,14-tetrahydrobenzo[f]naphtho[1,2-b]azocine-14-acetyl-8,9-dimethyl-7,8,13,14-tetrahydrobenzo[f]naphtho[1,2-b]azocine (74/26), C(23)H(23)NO, (II), exhibits threefold whole-molecule disorder involving both configurational and structural isomers. In (I) and in the predominant form of (II), the azocine rings adopt very similar conformations, forming boat-shaped rings having approximate twofold rotational symmetry. There are no direction-specific intermolecular interactions in the crystal structure of (I), but the molecules of (II) are weakly linked into chains by an aromatic pi-pi stacking interaction. The compounds were made under green conditions using an acid-catalysed cyclization process having very high atom utilization.

6.
Acta Crystallogr C ; 66(Pt 4): o206-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20354312

RESUMO

Molecules of the title compound, C(18)H(16)FNO, are linked into a three-dimensional framework structure by a combination of two C-H...O hydrogen bonds and three C-H...pi(arene) hydrogen bonds. Comparisons are made with the (2R,4R) diastereoisomer and with the corresponding pair of diastereoisomeric 7-chloro analogues.

7.
Acta Crystallogr C ; 66(Pt 4): o209-14, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20354313

RESUMO

In (2SR,4RS)-2-exo-vinyl-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(12)H(13)NO, (I), the molecules are linked by two independent C-H...pi(arene) hydrogen bonds to form sheets, such that all of the molecules in a given sheet are of the same configuration. The molecules of (2SR,4RS)-7-chloro-2-exo-(2-methylprop-1-enyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(14)H(16)ClNO, (II), are linked by a C-H...O hydrogen bond into C(4) chains, where all the molecules in a given chain are of the same configuration, whereas the molecules of (2SR,4RS)-8-chloro-9-methyl-2-exo-(2-methylprop-1-enyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(15)H(18)ClNO, (III), are linked into centrosymmetric dimers by pairs of symmetry-related C-H...pi(arene) hydrogen bonds. (2RS,4RS)-8-Chloro-9-methyl-2-endo-(2-methylprop-1-enyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(15)H(18)ClNO, (IV), is a diastereoisomer of (III) and, as for (II), a single C-H...O hydrogen bond links the molecules into C(4) chains, each containing molecules of a single configuration. The structure of (2SR,4RS)-8-chloro-9-methyl-2-exo-(prop-1-en-2-yl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(14)H(16)ClNO, (V), contains a C-H...O hydrogen bond which links pairs of molecules into centrosymmetric R(2)(2)(6) dimers. (2SR,4RS)-7,9-Dichloro-2-exo-(prop-1-en-2-yl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(13)H(13)Cl(2)NO, (VI), is an inversion twin containing both the (2S,4R) and (2R,4S) enantiomers in the space group P2(1), and a C-H...O hydrogen bond links molecules of a given configuration into simple C(3) chains.

8.
Acta Crystallogr C ; 65(Pt 9): o465-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19726863

RESUMO

In (2RS,4SR)-7-chloro-2-exo-(2-chloro-6-fluorophenyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(16)H(12)Cl(2)FNO, (I), molecules are linked into chains by a single C-H...pi(arene) hydrogen bond. (2RS,4SR)-2-exo-(2-Chloro-6-fluorophenyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(16)H(13)ClFNO, (II), is isomorphous with compound (I) but not strictly isostructural with it, as the hydrogen-bonded chains in (II) are linked into sheets by an aromatic pi-pi stacking interaction. The molecules of (2RS,4SR)-7-methyl-2-exo-(4-methylphenyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(18)H(19)NO, (III), are linked into sheets by a combination of C-H...N and C-H...pi(arene) hydrogen bonds. (2S,4R)-2-exo-(2-Chlorophenyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(16)H(14)ClNO, (IV), crystallizes as a single enantiomer and the molecules are linked into a three-dimensional framework structure by a combination of one C-H...O hydrogen bond and three C-H...pi(arene) hydrogen bonds.


Assuntos
Benzazepinas/química , Compostos de Epóxi/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Estereoisomerismo
9.
Acta Crystallogr C ; 65(Pt 9): o479-82, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19726866

RESUMO

4,4'-(Phenylmethylene)bis(6-allyl-3-chloro-2-methylaniline), C(27)H(28)Cl(2)N(2), (I), and 4,4'-(2-thienylmethylene)bis(6-allyl-3-chloro-2-methylaniline), C(25)H(26)Cl(2)N(2)S, (II), adopt similar molecular conformations, although the thienyl group in (II) exhibits orientational disorder over two sets of sites with occupancies of 0.614 (3) and 0.386 (3). The amino groups in both compounds are pyramidal. A single N-H...N hydrogen bond links the molecules of (I) into cyclic centrosymmetric dimers. Molecules of (II) are linked by an ordered C-H...pi(arene) hydrogen bond to form cyclic centrosymmetric dimers, and these dimers are linked into statistically interrupted chains by a second C-H...pi(arene) hydrogen bond involving a donor in the minor component of the disordered thienyl unit.


Assuntos
Aminas/química , Compostos de Anilina/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares
10.
Acta Crystallogr C ; 65(Pt 9): o487-91, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19726868

RESUMO

The molecules of (2RS,4SR)-2-exo-(5-bromo-2-thienyl)-7-chloro-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(14)H(11)BrClNOS, (I), are linked into cyclic centrosymmetric dimers by C-H...pi(thienyl) hydrogen bonds. Each such dimer makes rather short Br...Br contacts with two other dimers. In (2RS,4SR)-2-exo-(5-methyl-2-thienyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(15)H(15)NOS, (II), a combination of C-H...O and C-H...pi(thienyl) hydrogen bonds links the molecules into chains of rings. A more complex chain of rings is formed in (2RS,4SR)-7-chloro-2-exo-(5-methyl-2-thienyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(15)H(14)ClNOS, (III), built from a combination of two independent C-H...O hydrogen bonds, one C-H...pi(arene) hydrogen bond and one C-H...pi(thienyl) hydrogen bond.


Assuntos
Benzazepinas/química , Compostos de Epóxi/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares
11.
Biochemistry ; 48(32): 7608-13, 2009 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-19580327

RESUMO

Understanding protein-solute interactions is one of the sizable challenges of protein chemistry; therefore, numerous experimental studies have attempted to explain the mechanism by which proteins unfold in aqueous urea solutions. On the basis of kinetic evidence at low urea concentrations, (1)H NMR spectroscopic analysis, and molecular orbital calculations, we propose a mechanistic model for the denaturation of RNase A in urea. Our results support a direct interaction between urea and protonated histidine as the initial step for protein inactivation followed by hydrogen bond formation with polar residues, and the breaking of hydrophobic collapse as the final steps for protein denaturation. With the proposed model, we can rationalize apparently conflicting results in the literature about the mechanism of protein denaturation with urea.


Assuntos
Conformação Proteica , Desnaturação Proteica , Ribonuclease Pancreático/química , Ureia/química , Modelos Teóricos , Ressonância Magnética Nuclear Biomolecular , Ribonuclease Pancreático/metabolismo , Termodinâmica , Ureia/metabolismo , Água/química
12.
Acta Crystallogr C ; 65(Pt 4): o140-5, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19346609

RESUMO

(2R,4S)-7-Bromo-2-phenyl-2,3,4,5-tetrahydro-1,4-epoxynaphtho[1,2-b]azepine, C(20)H(16)BrNO, (I), exhibits evidence of a modest degree (ca 10%) of inversion twinning, while both (2RS,4SR)-7-bromo-2-(4-chlorophenyl)-2,3,4,5-tetrahydro-1,4-epoxynaphtho[1,2-b]azepine, C(20)H(15)BrClNO, (II), and (2RS,4SR)-2-(4-fluorophenyl)-2,3,4,5-tetrahydro-1,4-epoxynaphtho[1,2-b]azepine, C(20)H(16)FNO, (III), crystallize as genuine racemic mixtures. The molecules of (I) are linked into sheets by a combination of one C-H...O hydrogen bond and two C-H...pi(arene) hydrogen bonds, while those of (II) are linked into sheets of pi-stacked hydrogen-bonded chains. A combination of one C-H...O hydrogen bond and four independent C-H...pi(arene) hydrogen bonds links the molecules of (III) into a three-dimensional framework. The significance of this study lies in its finding, via comparison with the structures of some closely-related epoxybenzazepine analogues, of significant changes in crystal structures consequent upon small changes in the peripheral substituents.


Assuntos
Azepinas/química , Modelos Moleculares , Cristalografia por Raios X , Ligação de Hidrogênio , Estrutura Molecular
13.
Acta Crystallogr C ; 65(Pt 3): o92-6, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19265230

RESUMO

4-Hydroxy-2-vinyl-2,3,4,5-tetrahydro-1-benzazepine, C(12)H(15)NO, (I), and its 7-fluoro and 7-chloro analogues, namely 7-fluoro-4-hydroxy-2-vinyl-2,3,4,5-tetrahydro-1-benzazepine, C(12)H(14)FNO, (II), and 7-chloro-4-hydroxy-2-vinyl-2,3,4,5-tetrahydro-1-benzazepine, C(12)H(14)ClNO, (III), are isomorphous, but with variations in the unit-cell dimensions which preclude in compound (III) one of the weaker intermolecular interactions found in compounds (I) and (II). Thus the compounds are not strictly isostructural in terms of the structurally significant intermolecular interactions, although the corresponding atomic coordinates are very similar. The azepine rings adopt chair conformations. The molecules are linked by a combination of N-H...O and O-H...N hydrogen bonds into chains of edge-fused R(3)(3)(10) rings, which in compounds (I) and (II) are further linked into sheets by a single C-H...pi(arene) hydrogen bond. The significance of this study lies in its observation of isomorphism in compounds (I)-(III), and its observation of a sufficient variation in one of the cell dimensions effectively to alter the range of significant hydrogen bonds present in the crystal structures.


Assuntos
Antiprotozoários/química , Benzazepinas/química , Hidrocarbonetos Clorados/química , Hidrocarbonetos Fluorados/química , Cristalografia por Raios X , Ligação de Hidrogênio , Estrutura Molecular
14.
Curr Microbiol ; 58(4): 378-83, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19067045

RESUMO

The mineral phosphate-solubilizing (MPS) activity of a Pantoea agglomerans strain, namely MMB051, isolated from an iron-rich, acidic soil near Ciudad Piar (Bolívar State, Venezuela), was characterized on a chemically defined medium (NBRIP). Various insoluble inorganic phosphates, including tri-calcium phosphate [Ca(3)(PO(4))(2)], iron phosphate (FePO(4)), aluminum phosphate (AlPO(4)), and Rock Phosphate (RP) were tested as sole sources of P for bacterial growth. Solubilization of Ca(3)(PO(4))(2) was very efficient and depended on acidification of the external milieu when MMB051 cells were grown in the presence of glucose. This was also the case when RP was used as the sole P source. On the other hand, the solubilization efficiency toward more insoluble mineral phosphates (FePO(4) and AlPO(4)) was shown to be very low. Even though gluconic acid (GA) was detected on culture supernatants of strain MMB051, a consequence of the direct oxidation pathway of glucose, inorganic-P solubilization seemed also to be related to other processes dependent on active cell growth. Among these, proton release by ammonium (NH(4)(+) ) fixation appeared to be of paramount importance to explain inorganic-P solubilization mediated by strain MMB051. On the contrary, the presence of nitrate (NO(3)(-) ) salts as the sole N source affected negatively the ability of MMB051 cells to solubilize inorganic P.


Assuntos
Sedimentos Geológicos/microbiologia , Minerais/metabolismo , Pantoea/metabolismo , Fosfatos/metabolismo , Microbiologia do Solo , Fosfatos de Cálcio/metabolismo , Meios de Cultura , Ferro/química , Pantoea/isolamento & purificação , Solo/análise , Solubilidade , Venezuela
15.
Acta Crystallogr C ; 64(Pt 9): o514-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18758024

RESUMO

(2SR,4RS)-7-Chloro-2-exo-[(E)-styryl]-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(18)H(16)ClNO, (I), crystallizes as a racemic twin in the space group P2(1) and the molecules are linked into a chain of edge-fused R(3)(3)(9) rings by a combination of C-H...O and C-H...N hydrogen bonds. The diastereoisomer (2RS,4RS)-7-chloro-2-endo-[(E)-styryl]-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, (II), also crystallizes as a racemic twin, but in the space group P2(1)2(1)2(1), and a two-centre C-H...N hydrogen bond and a three-centre C-H...(O,N) hydrogen bond combine to link the molecules into a complex chain of rings. In (2R,4R)-7-fluoro-2-endo-[(E)-styryl]-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(18)H(16)FNO, (III), which is not isomorphous with (II), the molecules are linked by a single C-H...O hydrogen bond into simple chains, but the molecular arrangements in (II) and (III) are nonetheless very similar. The significance of this study lies in its observation of the variations in molecular configuration and conformation, and in the variation in the supramolecular aggregation, consequent upon modest changes in the peripheral substituents.


Assuntos
Antiprotozoários/química , Benzazepinas/química , Cristalografia por Raios X , Ligação de Hidrogênio , Conformação Molecular
16.
Acta Crystallogr C ; 63(Pt 9): o543-5, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17762128

RESUMO

In the title compound, C(6)H(8)N(2)O(2)S, also known as N-acetyl-2-thiohydantoin-alanine, the molecules are joined by N-H...O hydrogen bonds, forming centrosymmetric R2(2)(8) dimers; these dimers are linked by C-H...O interactions to form R2(2)(10) rings, thus forming C2(2)(10) chains that run along the [101] direction.


Assuntos
Imidazolidinas/química , Tioidantoínas/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Compostos de Sulfidrila/química
17.
Acta Crystallogr C ; 63(Pt 8): o448-50, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17675693

RESUMO

The crystal structure of the title compound, C(10)H(10)N(2)O(2).H(2)O, also known as L-5-benzylhydantoin monohydrate, is described in terms of two-dimensional supramolecular arrays built up from infinite chains assembled via N-H...O and O-H...O hydrogen bonds among the organic molecules and solvent water molecules, with graph-set R(3)(3)(10)C(5)C(2)(2)(6). The hydrogen-bond network is reinforced by stacking of the layers through C-H...pi interactions.


Assuntos
Compostos de Benzil/química , Imidazolidinas/química , Cristalografia por Raios X , Eletroquímica , Ligação de Hidrogênio , Isomerismo , Modelos Químicos , Conformação Molecular , Estrutura Molecular , Solventes/química , Água/química , Difração de Raios X
18.
Acta Crystallogr C ; 63(Pt 5): o303-5, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17478918

RESUMO

In the title compound, also known as N-carbamoyl-L-proline, C(6)H(10)N(2)O(3), the pyrrolidine ring adopts a half-chair conformation, whereas the carboxyl group and the mean plane of the ureide group form an angle of 80.1 (2) degrees. Molecules are joined by N-H...O and O-H...O hydrogen bonds into cyclic structures with graph-set R(2)(2)(8), forming chains in the b-axis direction that are further connected via N-H...O hydrogen bonds into a three-dimensional network.

19.
Parasitol. latinoam ; 61(1/2): 17-22, jun. 2006. ilus
Artigo em Espanhol | LILACS | ID: lil-432844

RESUMO

En este trabajo se determinó cualitativa y cuantitativamente la composición química de un extracto en benceno de ejemplares de Rhodnius prolixus en diferentes estadios ninfales y edades reproductivas de las hembras. El análisis fue realizado mediante técnicas uni- y bidimensionales (1D y 2D) de Resonancia Magnética Nuclear (RMN). Se han clasificado los compuestos químicos presentes en el extracto como A, B y C, según sus zonas de desplazamiento químico. El compuesto A, situado en la zona entre d 5,0 y 5,33 ppm, puede ser atribuido a hidrógenos olefínicos (alquenos) y está presente en todo los estadios ninfales y edades reproductivas, por lo que no es de utilidad para ser marcador de edades. El Compuesto C, situado en la zona entre 2,5 ppm y 3,5 ppm, representa distintas señales las cuales presumiblemente según sus desplazamientos químicos corresponden a hidrógenos sobre carbonos nitrogenados y sirve como marcador de edad para diferenciar entre los estadios ninfales y el comienzo de la edad adulta. El Compuesto B, presente en la zona entre 4 y 5 ppm, corresponde a un triacilglicerol, y es un marcador importante para diferenciar entre las hembras no ovipositoras (HNO) y ovipositoras (HO), ya que esta última edad carece de este compuesto. También es útil usar la relación de concentraciones de los compuestos A y B, que viene dada por la integral de la señal para determinar la diferencia de edades entre los estadios ninfales. Se proponen estas técnicas para determinar los estadios ninfales y las edades reproductivas de las hembras en una muestra de triatominos colectados en condiciones de campo, lo que revelaría información importante para conocer algunas de las variables de las que depende la capacidad vectora de estos insectos en la transmisión de la Enfermedad de Chagas.


Assuntos
Animais , Feminino , Estágios do Ciclo de Vida , Espectroscopia de Ressonância Magnética , Rhodnius/crescimento & desenvolvimento , Rhodnius/química , Benzeno , Doença de Chagas , Insetos Vetores/química , Biomarcadores , Ressonância Magnética Nuclear Biomolecular , Ninfa/crescimento & desenvolvimento , Ninfa/química
20.
J Ethnopharmacol ; 106(3): 327-32, 2006 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-16574358

RESUMO

Several species of Ferula genus have been used in folk medicine in digestive disorders, rheumatism, headache, arthritis, and as tranquilizers, antispasmodic and aphrodisiac. From the dry and powdered roots of Ferula hermonis Boiss was extracted the oxygenated sesquiterpene 1,5-trans-daucane type: ferutinine (1). The structure of (1) was established by spectroscopic methods as: IR, (1)H RMN, (13)C RMN, COSY, HMBC, HMQC, NOESY, EIMS, and CIMS. The possible signaling pathway of ferutinin (1) in nervous tissue in vitro was assessed and the results showed that this compound is able to increase nitric oxide synthase activity and inositol monophosphate accumulation (49%, each) in the median eminence of the rat brain, suggesting that compound (1) is associated to the activation of phosphoinositide breakdown and nitric oxide production (NO), the last is a gaseous intercellular messenger known to play a broad role in human biology from homeostasis to pathology.


Assuntos
Afrodisíacos/farmacologia , Ferula , Eminência Mediana/efeitos dos fármacos , Óxido Nítrico Sintase/biossíntese , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Afrodisíacos/administração & dosagem , Afrodisíacos/química , Masculino , Eminência Mediana/metabolismo , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Raízes de Plantas , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...