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1.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 43(2): 160-3, 2014 03.
Artigo em Chinês | MEDLINE | ID: mdl-24782371

RESUMO

OBJECTIVE: To determine the enantiomeric impurity contents of domestic timolol maleate in bulk drugs and eye drops. METHODS: Enantiomer impurity of timolol was assayed by chiral high performance liquid chromatography. The chromatographic conditions were as follows:chiralcel OD chiral column (4.6 mm ×150 mm, 5µm), detection wavelength:297 nm, mobile phase:hexane-isopropanol-diethylamine (480:20:1), column temperature:25 ℃, flow rate:1.0 ml/min, sample injection volume:5 µl. RESULTS: The resolution between R- and S-timolol was more than 4. The enantiomeric impurity contents were less than 0.67% on average in two batches of timolol maleate bulk drugs, and 0.31% on average in three batches of timolol maleate eye drops. CONCLUSION: Enantiomeric impurity contents in each batch of products all meet European Pharmacopoeia criteria, which can be used as references in Chinese Pharmacopoeia criteria.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Medicamentos , Soluções Oftálmicas/análise , Timolol/análise , Soluções Oftálmicas/normas , Estereoisomerismo , Timolol/normas
2.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 43(2): 164-7, 2014 03.
Artigo em Chinês | MEDLINE | ID: mdl-24782372

RESUMO

OBJECTIVE: To determine the contents of L-enantiomer impurity in valaciclovir hydrochloride. METHODS: Valaciclovir enantiomers were separated and determined by using chiral high performance liquid chromatography. Chromatographic conditions were as follows:CROWNPAK(®) CR(+) chiral column (4 mm×150 mm, 5 µm), detection wavelength:254 nm, mobile phase:water-methanol-perchloric acid (19:1:0.1), flow rate:0.75 ml/min, sample injection volume:10 µl. RESULTS: D-valaciclovir was completely separated from L-enantiomer impurity. The contents of L-enantiomer impurity were 0.65%-2.62% on average in 8 batches of valaciclovir hydrochloride. CONCLUSION: Enantiomeric impurity contents in each batch of products were all meet criteria of United States Pharmacopeia, which can be used in criteria of Chinese Pharmacopeia as references.


Assuntos
Aciclovir/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Valina/análogos & derivados , Aciclovir/análise , Estereoisomerismo , Valaciclovir , Valina/análise
3.
J Med Chem ; 52(23): 7732-52, 2009 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-19673490

RESUMO

A series of C7-O- and C20-O-amidated 2,3-dehydrosilybin (DHS) derivatives ((+/-)-1a-f and (+/-)-2), as well as a set of alkenylated DHS analogues ((+/-)-4a-f), were designed and de novo synthesized. A diesteric derivative of DHS ((+/-)-3) and two C23 esterified DHS analogues ((+/-)-5a and (+/-)-5b) were also prepared for comparison. The cell viability of PC12 cells, Fe(2+) chelation, lipid peroxidation (LPO), free radical scavenging, and xanthine oxidase inhibition models were utilized to evaluate their antioxidative and neuron protective properties. The study revealed that the diether at C7-OH and C20-OH as well as the monoether at C7-OH, which possess aliphatic substituted acetamides, demonstrated more potent LPO inhibition and Fe(2+) chelation compared to DHS and quercetin. Conversely, the diallyl ether at C7-OH and C20-OH was more potent in protection of PC12 cells against H(2)O(2)-induced injury than DHS and quercetin. Overall, the more lipophilic alkenylated DHS analogues were better performing neuroprotective agents than the acetamidated derivatives. The results in this study would be beneficial for optimizing the therapeutic potential of lignoflavonoids, especially in neurodegenerative disorders such as Alzheimer's and Parkinson's disease.


Assuntos
Alcenos/química , Amidas/química , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/farmacologia , Silimarina/síntese química , Silimarina/farmacologia , Doença de Alzheimer/tratamento farmacológico , Animais , Desenho de Fármacos , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/uso terapêutico , Humanos , Quelantes de Ferro/síntese química , Quelantes de Ferro/química , Quelantes de Ferro/farmacologia , Quelantes de Ferro/uso terapêutico , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Modelos Moleculares , Conformação Molecular , Neurônios/citologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/uso terapêutico , Células PC12 , Doença de Parkinson/tratamento farmacológico , Ratos , Silimarina/química , Silimarina/uso terapêutico , Relação Estrutura-Atividade , Xantina Oxidase/antagonistas & inibidores
4.
Zhongguo Zhong Yao Za Zhi ; 33(10): 1147-57, 2008 May.
Artigo em Chinês | MEDLINE | ID: mdl-18720865

RESUMO

OBJECTIVE: To investigate the chemical constituents of the herbs of Taraxacum mongolicum. METHOD: The chemical constituents were isolated by various column chromatographic methods and their structures elucidated mainly by NMR and MS evidences. RESULT: Forty-four components were obtained and identified were as artemetin (1), quercetin (2), quercetin-3', 4', 7-trime-thyl ether (3), luteolin (4), luteolin-7-O-beta-D-glucopyranoside (5), luteolin-7-O-beta-D-galactopyranoside (6), genkwanin (7), isoetin (8), hesperetin (9), genkwanin-4'-O-beta-D-lutinoside (10), hesperidin (11), quercetin-7-O-[beta-D-glucopyranosyl (1-->6) -beta-D-glucopyranoside (12), quercetin-3, 7-O-beta-D-diglucopyranoside (13), isoetin-7-O-beta-D-glucopyranosyl- 2'-O-alpha-L-arabinopyranoside (14), isoetin-7-O-beta-D-glucopyranosyl-2'-O-alpha-D-glucopyranoside (15), isoetin-7- O-beta-D-glucopyranosyl-2'-O-beta-D-xyloypyranoside (16), caffeic acid (17), furulic acid (18), 3-O-caffeoylquinic acid (19), 3, 5-di-O-caffeoylquinic acid (20), 3, 4-di-O-caffeoylquinic acid (21), 4, 5-di-O-caffeoylquinic acid (22), 1-hydroxymethyl-5-hydroxy-phenyl-2-O-beta-D-glucopyranoside (23), p-hydroxybenzoic acid (24), p-coumaric acid (25), 3, 5-dihydroxylbenzoic acid (26), gallic acid (27), gallicin (28), syringic acid (29), 3, 4-dihydroxybenzoic acid (30), caffeic acid ethyl ester (31), esculetin (32), rufescidride (33), mongolicumin A [6, 9, 10-trihydroxy-benzoxanthene-1, 2-dicarboxylic acid] (34), mongolicumin B [1 l-hydroxy-2-oxo-guaia-1 (10), 3, 5-trien-8, 12-lactone] (35), isodonsesquitin A (36), taraxacin (37), sesquiterpene ketolactone (38), taraxasteryl acetate (39), phi-taraxasteryl acetate (40) and lupenol acetate (41), palmitic acid (42), beta-sitosterol (43), and stigmasterol (44). CONCLUSION: Four compounds (14, 15, 34 and 35) were new compounds, compounds 1, 3, 6-13, 20-22, 30 and 31 were isolated from this genus for the first time, while compounds 18, 23-29, 32 and 37-42 were obtained from this species for the first time.


Assuntos
Medicamentos de Ervas Chinesas/química , Taraxacum/química , Flavonóis/química , Espectrometria de Massas
5.
J Nat Prod ; 71(1): 12-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18177011

RESUMO

Three new diarylheptanoids and one new monoterpenoid were isolated from the rhizomes of Zingiber officinale together with four known diarylheptanoids, 5-8. Their structures were elucidated mainly by spectroscopic methods, and they were deduced as 5-[4-hydroxy-6-(4-hydroxyphenethyl)tetrahydro-2 H-pyran-2-yl]-3-methoxybenzene-1,2-diol (1), sodium (E)-7-hydroxy-1,7-bis(4-hydroxyphenyl)hept-5-ene-3 S-sulfonate (2), sodium (E)-7-hydroxy-1,7-bis(4-hydroxyphenyl)hept-5-ene-3 R-sulfonate (3), and hydroxycineole-10-O-beta-D-glucopyranoside (4), respectively. Among the isolated compounds, compounds 1, 5, and 8 exhibited strong superoxide anion radical scavenging activities in a phenazine methosulfate-NADH system. In a more biological system, these compounds were demonstrated to exhibit potent protection against lipid peroxidation in mouse liver microsomes exposed to oxidative conditions. These compounds were subsequently tested on primary cultures of rat hepatocytes exposed to oxidative damage, and definitive cytoprotective actions were found.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Diarileptanoides/isolamento & purificação , Diarileptanoides/farmacologia , Monoterpenos/isolamento & purificação , Monoterpenos/farmacologia , Zingiber officinale/química , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Diarileptanoides/química , Sequestradores de Radicais Livres/farmacologia , Hepatócitos/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Masculino , Camundongos , Microssomos Hepáticos/efeitos dos fármacos , Estrutura Molecular , Monoterpenos/química , Ressonância Magnética Nuclear Biomolecular , Ratos , Ratos Sprague-Dawley , Rizoma/química
6.
J Biochem Biophys Methods ; 54(1-3): 103-13, 2002 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-12543494

RESUMO

Several important chiral phenethylamine agents such as mexiletine, fenfluramine, amphetamine, methamphetamine and N-n-propylamphetamine show stereoselective disposition in humans and large differences in therapeutic relevance and toxicity. To analyze the enantiomers of chiral amine drugs, stereoselective methods were developed to separate those enantiomers on an achiral capillary gas chromatography by pre-column chiral derivatization with S-(-)-N-(fluoroacyl)-prolyl chloride. The stereoselectivity and sensitivity can be improved by chiral derivatization. The methods established offer enantioselective, simple, flexible and economic approaches for the analysis of chiral amine drug enantiomers in biological fluids. The methods have been used to determine S-(+)-methamphetamine in human forensic samples and to analyze enantiomers of amphetamine and fenfluramine in rat liver microsomes.


Assuntos
Cromatografia Gasosa/métodos , Espectrometria de Massas/métodos , Fenetilaminas/análise , Prolina/análogos & derivados , Coloração e Rotulagem/métodos , Ionização de Chama/métodos , Fenetilaminas/química , Sensibilidade e Especificidade , Estereoisomerismo
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