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1.
Bioorg Med Chem Lett ; 25(20): 4657-63, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26338359

RESUMO

A new series of chloroquinoline-4H-chromene conjugates incorporating piperizine or azipane tethers were synthesized and their anti-malarial activity were evaluated against two Plasmodium falciparum strains namely 3D7 chloroquine sensitive (CQS) and K1 chloroquine resistant (CQR). Chloroquine was used as the standard and also reference for comparison. The conjugates exhibit intense UV absorption with λmax located at 342 nm (log ε=4.0), 254 nm (log ε=4.2), 223 nm (log ε=4.4) which can be used to spectrometrically track the molecules even in trace amounts. Among all the synthetic compounds, two molecules namely 6-nitro and N-piperazine groups incorporated 7d and 6-chloro and N-azapane incorporated 15b chloroquinoline-4H-chromene conjugates showed significant anti-malarial activity against two strains (3D7 and K1) of P. falciparum. These values are lesser than the values of standard antimalarial compound. Molecular docking results suggested that these two compounds showing strong binding affinity with P. falciparum lactate dehydrogenase (PfLDH) and also they occupy the co-factor position which indicated that they could be the potent inhibitors for dreadful disease malaria and specifically attack the glycolytic pathway in parasite for energy production.


Assuntos
Antimaláricos/farmacologia , Cloroquina/química , Cloroquina/farmacologia , Cromonas/química , Cromonas/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Animais , Antimaláricos/síntese química , Antimaláricos/química , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Simulação por Computador , Relação Dose-Resposta a Droga , Malária/tratamento farmacológico , Malária/parasitologia , Simulação de Acoplamento Molecular , Estrutura Molecular , Testes de Sensibilidade Parasitária , Plasmodium falciparum/metabolismo , Relação Estrutura-Atividade , Células Vero
2.
Org Biomol Chem ; 12(32): 6223-38, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-25007896

RESUMO

We have described the simple, convenient and high yielding one-pot synthesis of a library of highly functionalized hexa-substituted 1,4-dihydropyridines (1,4-DHPs) by 2-aminopyridine catalysed pseudo three-component reaction of nitroketene-N,S-acetals and aldehydes. This domino transformation involves formation of dihydropyridine ring by creation of two C-C bonds and one C-N bond, all of them taking place in a single synthetic operation. As the products precipitate out of the reaction simple filtration is enough to gather the products and thus, there is no need for work-up or column-chromatography. The C6-methylsulfanyl group in the product 1,4-DHPs was substituted with primary and secondary amines to provide 1,4-DHPs with further possibilities in structural diversity. As a demonstration of application of the method we have synthesised an analogue of nitenpyram, a neonicotinoid insecticide.

3.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 1): o180-1, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22259465

RESUMO

In the title compound, C(13)H(15)N(3)O(5), the O and N atoms of the nitro-methyl group and the methyl C atom of the ethyl group are disordered over two sets of sites with refined occupancies of 0.629 (7):0.371 (7) and 0.533 (8):0.467 (8), respectively. The dihydro-pyran ring has an extremely flattened conformation. An intra-molecular N-H⋯O hydrogen bond occurs. In the crystal, pairs of N-H⋯O hydrogen bonds link mol-ecules, forming inversion dimers. In addition, weak inter-molecular C-H⋯O hydrogen bonds are also present.

4.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 4): o898-9, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21754173

RESUMO

In the title compound, C(11)H(9)Cl(2)N(3)O(5), the dihydro-pyran ring adopts a near-half-chair conformation. The benzene ring makes a torsion angle of 5.02 (5)° with the dihydro-pyran ring. Adjacent mol-ecules are inter-linked through inter-molecular C-H⋯O, N-H⋯O and C-Cl⋯π [3.4743 (9) Å] inter-actions. The inter-molecular N-H⋯O hydrogen bond generates an R(2) (2)(12) motif, which is observed to contribute to the crystal packing stability. Moreover, the mol-ecular structure displays an S(6) motif formed by intra-molecular N-H⋯O hydrogen bonding.

5.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 5): o1276-7, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21754559

RESUMO

In the title compound, C(12)H(13)N(3)O(6), the dihydro-pyran ring adopts a near screw-boat conformation. The dihedral angle between the mean planes of the benzene and dihydro-pyran rings is 6.35 (5)°. An intra-molecular N-H⋯O hydrogen bond generates an S(6) motif, which stabilizes the mol-ecular conformation. In the crystal, weak inter-molecular C-H⋯O, N-H⋯O and C-H⋯π hydrogen bonds contribute to the stabilization of the packing.

6.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 6): o1395-6, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21754782

RESUMO

In the title compound, C(20)H(23)N(3)O(3), the dihydro-pyran ring adopts half-chair conformation. The chromene system makes a dihedral angle of 87.35 (5)° with the adjacent benzene ring. An intra-molecular N-H⋯O hydrogen bond generates an S(6) motif, which stabilizes the mol-ecular conformation. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds contribute to the stabilization of the packing.

7.
J Clin Neurosci ; 15(12): 1404-6, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18842416

RESUMO

Giant neurocysticercosis is a relatively rare condition. A 40-year-old woman presented with left focal seizures and progressive left hemiparesis. A CT scan of the brain showed multiple hypodense lesions in the right cerebral hemisphere with no contrast enhancement or perilesional edema. MRI showed multiple hypointense lesions in the right perisylvian area. At surgery, the lesion was found to be a single large parasitic cyst measuring approximately 5.0 x 4.5 x 5.0 cm and the same was excised. Histopathology showed a solitary cysticercus cyst with scolex. The patient made an uneventful recovery. This imaging appearance of giant neurocysticercosis is very unusual and only two similar instances have been reported thus far.


Assuntos
Encefalopatias/patologia , Imagem por Ressonância Magnética/métodos , Neurocisticercose/patologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Feminino , Humanos
8.
J Perinatol ; 27(11): 724-6, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17960144
10.
Diabet Med ; 13(8): 715-9, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8862945

RESUMO

A total of 105 subjects with impaired glucose tolerance were classified into two groups, 51 subjects with plasma glucose > 11.1 mmol l-1 in one of the blood samplings during OGTT, but at 2 h being less than < 11.1 mmol l-1 were classified as early hyperglycaemics. Fifty-four cases were classified as true IGT, with fasting plasma glucose < 7.8 mmol l-1 and post plasma glucose level between 7.8 and 11.1 mmol l-1. Age and sex matched groups of normals (healthy adults) and NIDDM cases without symptomatic secondary complications were also included in the study. Lipid peroxidation (LPO) product in plasma, erythrocyte, and erythrocyte cell membrane were found to be significantly elevated (p < 0.001) in IGT, early hyperglycaemia and diabetes mellitus while glycosylated haemoglobin was also higher. Antioxidant enzymes superoxide dismutase and catalase were significantly lower in red blood cells obtained from IGT and early hyperglycaemic groups. They were closer to the levels showed in NIDDM confirming that antioxidant deficiency is already present in subjects classified as impaired glucose tolerant. Among the antioxidant scavengers, reduced glutathione (GSH) and ascorbic acid are reduced by 15% and 20% in IGT and NIDDM, respectively. We conclude that antioxidant status is poor in both IGT and NIDDM, suggesting an overlap of frank diabetic state in those classified as IGT. It is possible that antioxidant therapy might retard progression from IGT to NIDDM.


Assuntos
Antioxidantes/análise , Diabetes Mellitus Tipo 2/sangue , Intolerância à Glucose/sangue , Adulto , Glicemia/análise , Estudos de Coortes , Membrana Eritrocítica/metabolismo , Eritrócitos/metabolismo , Feminino , Glutationa/sangue , Humanos , Peroxidação de Lipídeos , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Peroxidases/sangue , Valores de Referência , Superóxido Dismutase/sangue , Vitaminas/sangue
11.
Cell Biol Int ; 19(12): 987-93, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9721623

RESUMO

Erythrocytes isolated from 131 cases of Non-Insulin Dependent Diabetes Mellitus (NIDDM) were studied for lipid peroxidation, antioxidant defences, and the maximum peroxidisable substrate in the cell membrane. Antioxidant defences are lowered in NIDDM, followed by significant rise in lipid peroxidation products. However, in the erythrocyte membrane, the total polyunsaturated peroxidisable lipids are lower than in normal erythrocytes which may be a causative factor affecting the survival of the cells.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Membrana Eritrocítica/enzimologia , Peroxidação de Lipídeos/fisiologia , Estresse Oxidativo/fisiologia , Idoso , Antropometria , Ácido Ascórbico/sangue , Azidas/farmacologia , Catalase/metabolismo , Membrana Eritrocítica/efeitos dos fármacos , Feminino , Depuradores de Radicais Livres/metabolismo , Glutationa/sangue , Glutationa Peroxidase/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Masculino , Pessoa de Meia-Idade , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Vitamina A/sangue , Vitamina E/sangue
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