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1.
Yao Xue Xue Bao ; 49(8): 1181-7, 2014 Aug.
Artículo en Zh | MEDLINE | ID: mdl-25322562

RESUMEN

To investigate theological properties of common hydrophilic gel excipients such as Carbopol based on viscosity, the viscosity was determined by rotation method and falling-ball method. Linear regression was made between ln(eta) and concentration, the slope of which was used to explore the relation between viscosity and concentration of different excipients. The viscosity flow active energy (E(eta)) was calculated according to Arrhenius equation and was used to investigate the relation between viscosity and temperature of different excipients. The results showed that viscosities measured by two methods were consistent. Concentration of guargum (GG) and hydroxypropylmethyl cellulose (HPMC) solution had a great influence on the viscosity, k > 5; while concentration of polyvinylpyrrolidone-K30 (PVP-K30) and polyethylene glycol 6000 (PEG6000) exerted a less effect on viscosity, k < 0.2; viscosity flow active energy of different excipients were close, which ranged from 30 to 40 kJ x mol(-1). Therefore, theological properties study could provide the basis for application of excipients and establish a foundation for the research of relation between excipients structure, property and function.


Asunto(s)
Excipientes/química , Geles/química , Reología , Polietilenglicoles/química , Polivinilos/química , Povidona/química , Temperatura , Viscosidad
2.
Drug Dev Ind Pharm ; 39(5): 744-51, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22694127

RESUMEN

The purpose of the present study is to develop a novel method to improve the dissolution of water-insoluble drug ibuprofen and the gastric tolerance of this non-steroidal anti-inflammatory drug which has potentially serious gastrointestinal side effects. This method is based on ion exchange of ion-exchange fibers. Water-insoluble drug ibuprofen was dispersed in deionized water, and then the ion-exchange fibers in OH(-) type was immersed in it. Ibuprofen and the active groups of the ion-exchange fibers combined into ion pairs based on the acid-base reaction. This drug carrier did not release drugs in deionized water, but in water solution containing other ions it would release the drugs into the solution by ion exchange. Confirmed by the X-ray diffraction and the scanning electron microscopy, the ibuprofen combined onto the ion-exchange fibers was in a highly molecular level dispersed state. The improved dissolution of ibuprofen ion-exchange fiber complexes is likely to originate from this ibuprofen's highly dispersed state. Due to this, ibuprofen's highly dispersed state, ibuprofen ion-exchange fiber complexes significantly decreases the gastrointestinal side effects of ibuprofen by avoiding the solid ibuprofen's educing. The present study showed that ibuprofen ion-exchange fiber complexes have the two-fold advantages. One is to improve the dissolution of ibuprofen. The other is to decrease the ibuprofen's gastrointestinal toxicity.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Química Farmacéutica , Tracto Gastrointestinal/efectos de los fármacos , Ibuprofeno/química , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/efectos adversos , Portadores de Fármacos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/prevención & control , Enfermedades Gastrointestinales/prevención & control , Ibuprofeno/administración & dosificación , Ibuprofeno/efectos adversos , Intercambio Iónico , Masculino , Ratas , Ratas Sprague-Dawley , Solubilidad
3.
Ying Yong Sheng Tai Xue Bao ; 34(1): 213-220, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36799396

RESUMEN

We examined the antifungal characteristics of linalool against Botrytis cinerea using plate inhibition assay and spore germination assay, and assessed the capacity of linalool in controlling tomato gray mold disease via tomato pot inoculation assay. The results showed that linalool exhibited strong inhibitive effects on mycelial growth of B. cinerea, with an EC50 value of 0.581 mL·L-1. In the spore germination test, linalool treatment inhibited spore germination in a dose-dependent manner. The electric conductivity and the malondialdehyde (MDA) contents were significantly increased in linalool-treated B. cinerea than that of the control, indicating that linalool induced oxidative damage and destroyed the cell membrane integrity in B. cinerea. The activities of the superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) in the linalool-treated B. cinerea were decreased significantly by 27.4%, 68.9% and 26.0%, respectively, suggesting that linalool inhibited the antioxidant activity of B. cinerea. In the pot experiment, the diameter of lesions in linalool-treated tomatoes was significantly smaller than that of the control. The activities of SOD, POD, CAT, polyphenol oxidase, and phenylalnine ammonialyase in the linalool-treated tomatoes increased, while the MDA content decreased, suggesting that linalool could alleviate the oxidative damage caused by B. cinerea and promote plant disease resistance. In summary, linalool had inhibitory effect on the growth of B. cinerea and could control gray mold disease in tomatoes. These findings could lay the foundation for developing bota-nical antifungal agents for management of tomato gray mold disease.


Asunto(s)
Solanum lycopersicum , Botrytis , Superóxido Dismutasa , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/microbiología
4.
Yao Xue Xue Bao ; 47(9): 1227-30, 2012 Sep.
Artículo en Zh | MEDLINE | ID: mdl-23227555

RESUMEN

The inclusion complex of isotretinoin was prepared by sealed-control temperature method and amylose was used as carrier. The formation of inclusion complex was confirmed by powder X-ray diffraction and DSC. The equation of enzymatically-controlled drug release was established by kinetic theory, and the release characteristic of drug was confirmed by using the kinetic equation. The results show that the drug release was attributed to first order reaction without alpha-amylase. However, with alpha-amylase, the drug release was an acceleration process by the effect of both dissociation and enzymatic hydrolysis simultaneously. The research indicates that drug release from the inclusion complex was modulated by the addition of alpha-amylase.


Asunto(s)
Amilosa/química , Fármacos Dermatológicos/química , Isotretinoína/química , Rastreo Diferencial de Calorimetría , Portadores de Fármacos/química , Hidrólisis , Cinética , Temperatura , Difracción de Rayos X , alfa-Amilasas/química
5.
J Asian Nat Prod Res ; 13(9): 861-8, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21830892

RESUMEN

The metabolites of baicalein in human plasma were investigated after taking baicalein, which is one of the main bioactive flavones in Scutellaria baicalensis Georgi. Five metabolites (M1-M5) together with the parent drug baicalein (P) were detected and identified by the HPLC-diode-array detector (DAD) and LC-MS/MS methods. Among them, 7-methoxybaicalein 6-O-glucuronide (M5) is a new metabolite. Based on the results, the proposed metabolic pathway of baicalein in humans was inferred.


Asunto(s)
Flavanonas/aislamiento & purificación , Glucurónidos/aislamiento & purificación , Scutellaria baicalensis/química , Cromatografía Líquida de Alta Presión , Flavanonas/análisis , Flavanonas/sangre , Flavanonas/química , Flavanonas/metabolismo , Glucurónidos/sangre , Glucurónidos/química , Humanos , Estructura Molecular
6.
Yao Xue Xue Bao ; 46(2): 221-6, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21539152

RESUMEN

The purpose of the present study is to use beta-cyclodextrin polymers (beta-CDP) with different cross-linked degree (CLD) to form inclusion complexes with ibuprofen and examine the effects of structural and compositional factors of beta-CDP on its drug loading and release behaviors. A series of beta-CDP with different CLD were synthesized and characterized by Fourier Transform Infrared Spectroscopy (FT-IR) and 13C NMR spectrum. The beta-CDP was systemically characterized for the relation between the CLD of beta-CDP and the drug loading and release as well. The results of FT-IR and 13C NMR showed that similar peak-shaped vibration of beta-CDP and beta-CD implies that the polymer keeps the original characteristic structure of beta-CD. The CLD of the beta-CDP played a critical role in the drug loading and release, increasing the CLD resulted in reduction of drug loading, but increase in drug release.


Asunto(s)
Reactivos de Enlaces Cruzados/química , Sistemas de Liberación de Medicamentos , Preparaciones Farmacéuticas/administración & dosificación , Polímeros/química , beta-Ciclodextrinas/química , Isótopos de Carbono , Preparaciones de Acción Retardada , Portadores de Fármacos , Composición de Medicamentos , Ibuprofeno/administración & dosificación , Ibuprofeno/química , Espectroscopía de Resonancia Magnética , Preparaciones Farmacéuticas/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier
7.
J Comb Chem ; 12(2): 260-5, 2010 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-20092329

RESUMEN

An efficient synthetic procedure for the preparation of the unusual charge-separated pyridinium-Meldrum acid and N,N-dimethylbarbiturate acid zwitterionic salts was developed though a unique one-pot four-component reaction involving pyridine, aromatic aldehyde, Meldrum acid or N,N-dimethylbarbituric acid, and p-nitrobenzyl bromide in acetonitrile. By varying combinations of four components involving nitrogen-containing heterocycles, we conveniently established reactive alpha-halomethylene compounds, aldehydes and beta-dicarbonyl compounds a library of zwitterionic salts.


Asunto(s)
Barbitúricos/química , Dioxanos/química , Compuestos de Piridinio/química , Sales (Química)/síntesis química , Compuestos Heterocíclicos/química , Modelos Moleculares
8.
Yao Xue Xue Bao ; 45(7): 909-13, 2010 Jul.
Artículo en Zh | MEDLINE | ID: mdl-20931791

RESUMEN

The inclusion compound of amylose and salicylic acid (SA) was prepared by a sealed temperature control method, and the formation of the inclusion compound was confirmed by IR spectrum and powder X-ray diffraction. The kinetic parameters of dissociation of amylose/SA compound were studied by the nonisothermal method which was defined as a relationship between the dissociation ratio and time. The values of activation energy (Ea) and frequency factors (InA) were calculated by a nonlinear least-square method. In this study, the formation of the inclusion compound of amylose/SA was confirmed by IR spectrum powder X-ray diffraction. SA existed in a molecule form in the spiral stouction of amylose. The dissociation of amylose/SA compound was attributed to first order reaction. The values of Ea calculated by the nor-isothermal method were 21.71 and 22.41 kJ x mol(-1) at heating rate 5 and 10 degrees C x h(-1), respectively. The corresponding isothermal method value of Ea was 22.17 kJ x mol(-1); the calculated InA values were 9.32 and 10.08 at heating rate 5 and 10 degrees C x h(-1), respectively. The corresponding isothermal method lnA value was 9.26. The results were in good agreement with Ea values and lnA values by isothermal method. These results indicated that the non-isothermal method described in this study could be adequately used for the stability study of inclusion compound and was a rapid and accurate method for the determination of kinetic parameters.


Asunto(s)
Amilosa/química , Ácido Salicílico/química , Estabilidad de Medicamentos , Calor , Cinética , Difracción de Polvo , Espectrofotometría Infrarroja , Termodinámica
9.
J Org Chem ; 74(19): 7403-6, 2009 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-19739607

RESUMEN

An efficient synthetic procedure for the preparation of fused 2,3-dihydrofuran derivatives was developed with the assistance of pyridinium ylide. A sequential one-pot, two-step tandem reaction starting from pyridine, aromatic aldehyde, dimedone, or 4-hydroxycoumarin and alpha-phenacyl bromide or p-nitrobenzyl bromide with triethylamine as catalyst proceeded smoothly in acetonitrile. (1)H NMR spectroscopy and single-crystal analysis demonstrated that the obtained 2,3-dihydrofurans are trans isomers.


Asunto(s)
Furanos/síntesis química , Compuestos de Piridinio/química , Furanos/química , Estructura Molecular , Estereoisomerismo
10.
J Org Chem ; 74(2): 710-8, 2009 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-19072237

RESUMEN

Polysubstituted pyrido[1,2-a]benzimidazole derivatives are efficiently produced in moderate yields in a novel one-pot, four-component reaction from pyridine or 3-picoline, chloroacetonitrile, malononitrile, and aromatic aldehyde in refluxing acetonitrile. The mechanism of this novel reaction was believed involving the formation of polysubstituted benzenes with subsequent substitution and annulation reaction of pyridine. All pyrido[1,2-a]benzimidazoles, polysubstituted benzenes, polysubstituted indoles, and some key reaction intermediates are characterized by (1)H and (13)C NMR, MS, IR spectra, and elemental analysis as well as X-ray crystallography.

11.
J Comb Chem ; 11(6): 1007-10, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19603746

RESUMEN

A sequential one-pot two-step tandem reaction for efficient synthesis of polysubstituted cyclopropanes has been developed. The three-component reaction of alpha-halogenated methylene compounds, aromatic aldehydes, and acetonitrile derivatives produced first the intermediates pyridinium salts and electron-deficient olefins, followed by cyclopropanation of pyridinium ylide with electron-deficient olefins in situ to afford polysubstituted cyclopropanes. Target compounds were obtained in high yields and were diastereomerically pure after recrystallization.


Asunto(s)
Técnicas Químicas Combinatorias/métodos , Ciclopropanos/síntesis química , Compuestos de Piridinio/síntesis química , Alquenos/síntesis química , Alquenos/química , Cristalografía por Rayos X , Ciclización , Ciclopropanos/química , Modelos Moleculares , Estructura Molecular , Compuestos de Piridinio/química , Estereoisomerismo
12.
Chem Commun (Camb) ; (12): 1440-2, 2008 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-18338049

RESUMEN

Polysubstituted benzene derivatives with an unprecedented substitution pattern are produced in a novel one-pot multi-component cyclization reaction from pyridine, ethyl alpha-bromoacetate, malononitrile and aromatic aldehyde in refluxing acetonitrile.


Asunto(s)
Acetatos/química , Aldehídos/química , Derivados del Benceno/síntesis química , Nitrilos/química , Derivados del Benceno/química , Cristalografía por Rayos X , Ciclización , Modelos Moleculares , Estructura Molecular , Estereoisomerismo
13.
Zhongguo Zhong Yao Za Zhi ; 32(3): 218-21, 2007 Feb.
Artículo en Zh | MEDLINE | ID: mdl-17432142

RESUMEN

OBJECTIVE: In the present study, using paeonol as model drug, a new sealed-control temperature method of preparing inclusion complex was developed, the effects of heating temperature, heating time, and crystallinity of beta-cyclodextrin (beta-CD) on formation of inclusion complex and release of the drug were investigated. METHOD: A physical mixture of paeonol and beta-CD was sealed in a container, and heated at the desired temperature for the specified time. The inclusion complex of paeonol and beta-CD was confirmed by IR spectrum and powder X-ray diffraction. RESULT: The results indicated that the inclusion complex formation of paeonol beta-CD by sealed-control temperature method was affected by heating temperature, heating time, and crystallinity of beta-CD. The inclusion complex was able to inhibit sublimation of paeonol, and dissolution rate of paeonol was increased when the paeonol was included by beta-CD. CONCLUSION: Preparation of inclusion complex was simple and quick by sealed-control temperature method.


Asunto(s)
Acetofenonas/química , Composición de Medicamentos/métodos , Temperatura , beta-Ciclodextrinas/química , Cristalización , Calor , Solubilidad , Espectrofotometría Infrarroja , Difracción de Rayos X
14.
Org Biomol Chem ; 5(6): 945-51, 2007 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-17340010

RESUMEN

A one-pot, effective synthesis of pyridines by a modified Kröhnke procedure is described. Polysubstituted annulated pyridines were synthesized in high yields by four-component, one-pot cyclocondensation reactions of N-phenacylpyridinium bromide, aromatic aldehydes, acetophenones or cyclic ketones in the presence of ammonium acetate and acetic acid, assisted by microwave irradiation. In this procedure, cyclic ketones with two alpha-CH(2) groups yield annulated pyridines with additional alpha-benzylidene groups, which are derived in situ from double aldol condensation of cyclic ketones with two moles of aromatic aldehydes.


Asunto(s)
Microondas , Piridinas/síntesis química , Cristalografía por Rayos X , Piridinas/química
15.
Zhongguo Zhen Jiu ; 26(2): 123-5, 2006 Feb.
Artículo en Zh | MEDLINE | ID: mdl-16541864

RESUMEN

OBJECTIVE: To promote the study on standardization of attitude of selecting point and posture of nee dling, so as to ensure safety of acupuncture and increase clinical therapeutic effect. METHODS: Study, analyze and clinically test and verify on literature of past dynasties, and differentiate and analyze differences and significances of attitude of selecting point and posture of needling, indicate the reasonable parts of ancient and modern various theories, and relative contents should be purified, corrected in time, and put forward a proposal on the standardization. CONCLUSION: Attitude of selecting point and posture of needling have close relation and have a certain difference; the experience of predecessors should be explored and systematized, and present confusion and out-of-date contents should be purified and relative standards should be established as early as possibly.


Asunto(s)
Terapia por Acupuntura , Acupuntura , Puntos de Acupuntura , Confusión , Humanos , Postura , Estándares de Referencia
16.
Zhongguo Zhen Jiu ; 25(3): 203-6, 2005 Mar.
Artículo en Zh | MEDLINE | ID: mdl-16312933

RESUMEN

OBJECTIVE: To promote the study on standardization of needling depth of acupoints, ensure safety of needling, and promote internationally academic exchanges of acupuncture and moxibustion. METHODS: Study, analyze ancient and present literature of acupuncture and moxibustion, and compare the differences in needling depth, measure unit, description methods, and the causes and trend, and indicate confusion at present, and put forward a proposition for establishing standardization of needling depth. CONCLUSION: There are a lot of confusions in needling depth of acupoints from the ancient times to the present, which produces severe unfavorable influence on standardization and international exchanges of acupuncture and moxibustion science, and it remains to be studied for the standardization as early as possibly.


Asunto(s)
Puntos de Acupuntura , Agujas , Acupuntura , Terapia por Acupuntura , Humanos , Moxibustión
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