RESUMEN
Electrochemical properties of eugenol were investigated on a graphene modified carbon paste electrode (CPE) by using voltammetric methods, which exhibited a well-defined irreversible peak at about 0.7V vs Ag/AgCl, NaCl (3M) in Britton-Robinson buffer at pH 2.0. Mechanism of the electrochemical reaction of eugenol was studied by performing density functional theory (DFT) computations and mass spectroscopic analysis. (CPCM:water)-wB97XD/aug-cc-PVTZ//(CPCM:water)-wB97XD/6-31G(d) level calculations predicted that the formation of product P2, possessing a para-quinoid structure, is preferred rather than the product P1, suggested in the literature, having an ortho-quinoid system. Determination of eugenol in a pharmaceutical sample was realized in the light of the electrochemical findings, and a validated voltammetric method for quantitative analysis of eugenol in a pharmaceutical formulation was proposed. The differential pulse voltammogram (DPV) peak currents were found to be linear in the concentration range of 1.0 × 10-7 to 1.7 × 10-5M. The limit of detection (LOD) and the limit of quantification (LOQ) were obtained to be 7.0 × 10-9 and 2.3 × 10-8, respectively.
Asunto(s)
Electroquímica/instrumentación , Eugenol/análisis , Eugenol/química , Grafito/química , Calibración , Electrodos , Concentración de Iones de Hidrógeno , Límite de Detección , Pomadas , Oxidación-ReducciónRESUMEN
Solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC) and nanoemulsion (NE) of lornoxicam (LRX) were prepared for the treatment of painful and inflammatory conditions of the skin. Compritol® 888 ATO, Lanette® O and oleic acid were used as solid and liquid lipids. SLN, NLC and NE were found physically stable at various temperatures for 6 months. Case I diffusional drug release was detected as the dominant mechanism indicating Fickian drug diffusion from nanoparticles and nanoemulsion. The highest rate of drug penetration through rat skin was obtained with NE followed by NLC, SLN and a gel formulation. Nanoformulations significantly increased drug penetration through rat skin compared to the gel (p<0.05). Thus, SLN, NLC and NE of LRX can be suggested for relieving painful and inflammatory conditions of the skin.
Asunto(s)
Portadores de Fármacos/química , Lípidos/química , Nanopartículas , Piroxicam/análogos & derivados , Administración Cutánea , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacocinética , Liberación de Fármacos , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Emulsiones , Ácidos Grasos/química , Alcoholes Grasos/química , Inflamación/tratamiento farmacológico , Inflamación/patología , Masculino , Ácido Oléico/química , Dolor/tratamiento farmacológico , Dolor/patología , Piroxicam/administración & dosificación , Piroxicam/química , Piroxicam/farmacocinética , Ratas , Ratas Wistar , Absorción Cutánea , Enfermedades de la Piel/tratamiento farmacológico , Enfermedades de la Piel/patología , Temperatura , Factores de TiempoRESUMEN
Simple, rapid spectrophotometric, and reverse-phase high performance liquid chromatographic methods were developed for the concurrent analysis of 17-beta-estradiol (ESR) and drospirenone (DRS). The spectrophotometric method was based on the determination of first derivative spectra and determined ESR and DRS using the zero-crossing technique at 208 and 282 nm, respectively, in methanol. The linear range was 0.5-32.0 µg·mL(-1) for DRS and 0.5-8.0 µg·mL(-1) for EST. The limit of detection (LOD) values were 0.14 µg·mL(-1) and 0.10 µg·mL(-1) and limit of quantification (LOQ) values were 0.42 µg·mL(-1) and 0.29 µg·mL(-1) for ESR and DRS, respectively. The chromatographic method was based on the separation of both analytes on a C18 column with a mobile phase containing acetonitrile and water (70 : 30, v/v). Detection was performed with a UV-photodiode array detector at 279 nm. The linear range was 0.08-2.5 µg·mL(-1) for DRS and 0.23-7.5 µg·mL(-1) for EST. LOD values were 0.05 µg·mL(-1) and 0.02 µg·mL(-1) and LOQ values were 0.15 µg·mL(-1) and 0.05 µg·mL(-1) for ESR and DRS, respectively. These recommended methods have been applied for the simultaneous determination of ESR and DRS in their tablets.
RESUMEN
Liquid chromatography coupled to a silver electrode based flow-through amperometric detector (LC-EC-Ag) was developed for the determination of aminothiols in white wines. The C18 reversed phase LC system operated in the isocratic mode at 0.7 mL min(-1) and used an acidic mobile phase composed of formic acid, EDTA, sodium nitrate, sodium hydroxide, and methanol 1% (v/v) at pH 4.5. The working electrode operated at 0.08 V vs Ag/AgCl, 3M KCl and its manual cleaning was realized once a month by smoothing on a polishing cloth. The analyzed aminothiols were resolved and eluted within 4 min, and all standard curves were linear in the range 2×10(-7)-2×10(-5) M. The analyzed wine samples needed no preparation other than dilution with the mobile phase. The concentration of cysteine (CYS), homocysteine (HCYS), glutathione (GSH) and N-acetylcysteine (NAC) in bottled white wines, determined by the method of standard addition, was found to be in the low µM range (0.2-2 mg L(-1)) depending on the wine type and its age.
Asunto(s)
Aminoácidos Sulfúricos/análisis , Glutatión/análisis , Electrodos de Iones Selectos , Plata/química , Compuestos de Sulfhidrilo/análisis , Vino/análisis , Cromatografía Liquida/métodos , Electroquímica/métodosRESUMEN
A new high-performance liquid chromatographic method is described for the determination of bisoprolol in human plasma. The proposed method was based on the derivatization of bisoprolol with 4-chloro-7-nitro-2,1,3-benzoxadiazole in borate buffer at pH 9.5 to yield a fluorescent product. Chromatographic separation of bisoprolol was achieved by using isocratic elution at a flow rate of 1.2 mL/min on a C18 reversed-phase column (Inertsil, 4 µm, 150 4.6 mm) at 40°C. The mobile phase used for the analysis was methanol-water (70:30, % v/v). Fluorescence detector was used at the excitation and emission wavelengths of 458 and 525 nm, respectively. The method was validated for linearity, limit of detection, limit of quantification, precision, accuracy, recovery and system suitability. The assay was linear over the concentration range of 10-2000 ng/mL. This method was applied in pharmacokinetic studies of bisoprolol preparations in healthy volunteers.
Asunto(s)
Bisoprolol/sangre , Cromatografía Líquida de Alta Presión/métodos , 4-Cloro-7-nitrobenzofurazano , Adulto , Bisoprolol/farmacocinética , Estabilidad de Medicamentos , Femenino , Humanos , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados , Espectrometría de FluorescenciaRESUMEN
A new, simple and sensitive spectrofluorimetric method has been developed for the determination of aliskiren (ALS) in dosage forms and human urine. The method is based on the reaction between ALS and fluorescamine in borate buffer solution, pH 9, to give a highly fluorescent derivative which is measured at 482 nm after excitation at 382 nm. The factors affecting the reaction were carefully studied. The fluorescence intensity concentration plots were rectilinear over the range 140-1400 ng/mL with a limit of detection 13.47 ng/mL and limit of quantitation 40.81 ng/mL. The developed method was successfully applied to the analysis of the drug in tablets and human urine; the average recoveries (n = 6) were 99.88 ± 0.38% and 99.57 ± 0.44%, respectively. The analytical performance of the method was fully validated and the results were satisfactory. The stability of the drug was studied by subjecting it to acidic, basic, oxidative and thermal degradation.
Asunto(s)
Amidas/análisis , Amidas/orina , Fumaratos/análisis , Fumaratos/orina , Espectrometría de Fluorescencia/métodos , Comprimidos/análisis , Amidas/química , Antihipertensivos/análisis , Antihipertensivos/orina , Boratos/química , Tampones (Química) , Calibración , Estabilidad de Medicamentos , Femenino , Fluorescamina/química , Fluorescencia , Fumaratos/química , Humanos , Concentración de Iones de Hidrógeno , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Temperatura , Factores de TiempoRESUMEN
A simple and sensitive method has been developed and validated for the determination of aliskiren (ALS) in its dosage forms and spiked plasma. The method was based on the reaction of the drug with dansyl chloride in the presence of bicarbonate solution of pH 10.5 to give a highly fluorescent derivative which was measured at 501 nm with excitition at 378 nm in dichloromethane. Different experimental parameters affecting the development of the method and stability were carefully studied and optimized. The calibration curves were linear over the concentration ranges of 100-700 and 50-150 ng/mL for standard solution and plasma, respectively. The limits of detection were 27.52 ng/mL in standard solution, 4.91 ng/mL in plasma. The developed method was successfully applied to the analysis the drug in the commercial tablets and spiked plasma samples. The mean recovery of ALS from tablets and plasma was 100.10 and 97.81%, respectively. A proposal of the reaction pathway was presented.
Asunto(s)
Amidas/análisis , Amidas/sangre , Compuestos de Dansilo/química , Fumaratos/análisis , Fumaratos/sangre , Amidas/química , Calibración , Fumaratos/química , Humanos , Concentración de Iones de Hidrógeno , Sensibilidad y Especificidad , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Comprimidos/químicaRESUMEN
Simple and sensitive spectrofluorometric and HPLC methods for the determination of ribavirin (RIB) were developed. The methods were based on the reaction of the 5'-hydroxyl group of the sugar moiety in RIB with dansyl chloride in a bicarbonate solution (pH 10.5) to form a fluorescent derivative. The first method was based on measuring the fluorescence intensity of the derivative in dichloromethane at 529 nm (excitation at 382 nm). The second method was HPLC separation of the derivative on a reversed-phase C(18) column with fluorescence detection. The linear ranges were 200-900 and 50-1000 ng/mL for the spectrofluorometric and HPLC methods, respectively. The derivatization product was characterized by spectroscopic methods. The proposed methods were successfully applied to analysis of the capsules.
Asunto(s)
Antivirales/análisis , Cápsulas/análisis , Cromatografía Líquida de Alta Presión/métodos , Compuestos de Dansilo/química , Ribavirina/análisis , Espectrometría de Fluorescencia/métodos , Fluorescencia , Colorantes Fluorescentes/química , Concentración de Iones de HidrógenoRESUMEN
The immobilization of tyrosinase onto glutaraldehyde activated streptavidine magnetic particles and subsequent retention onto a magnetized carbon paste electrode for the amperometric assay of tyrosinase inhibitors is described. Tyrosine was used as substrate as it is the first substrate in the melanogenesis process. The sensing mode is based on monitoring the decrease of the amperometric signal corresponding to the electrochemical reduction of dopaquinone enzymatically generated. This current decrease is due to the presence of inhibitors acting directly on the enzyme or inhibitors acting on the product of the enzymatic reaction, i.e. dopaquinone. The methodology is designed for the evaluation of the inhibitory potency of the most frequently used active substances in cosmetic marketed products against hyperpigmentation such as kojic acid, azelaic acid and benzoic acid. These compounds bind to the tyrosinase active center. Ascorbic acid is also investigated as it interrupts the synthesis pathway of melanin by reducing the melanin intermediate dopaquinone back to l-dopa. By comparing the obtained IC(50), under the same experimental conditions, the order of their inhibitory potency was: kojic acid (IC(50)=3.7 × 10(-6)M, K(i)=8.6 × 10(-7)M), ascorbic acid (IC(50)=1.2 × 10(-5)M), benzoic acid (IC(50)=7.2 × 10(-5)M, K(i)=2.0 × 10(-5)M) and azelaic acid (IC(50)=1.3 × 10(-4)M, K(i)=4.2 × 10(-5)M) in close agreement with literature spectrophotometric inhibition data using the soluble tyrosinase.
Asunto(s)
Técnicas Biosensibles/métodos , Blanqueadores/análisis , Inhibidores Enzimáticos/análisis , Magnetismo , Monofenol Monooxigenasa/química , Nanotecnología/métodos , Piel/efectos de los fármacos , Agaricales/enzimología , Blanqueadores/farmacología , Electroquímica , Inhibidores Enzimáticos/farmacología , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Melaninas/biosíntesis , Monofenol Monooxigenasa/metabolismo , Reproducibilidad de los Resultados , Piel/metabolismo , Estreptavidina/metabolismoRESUMEN
Two accurate, easy spectrophotometric methods for the determination of doxazosin mesylate were described. The first method was based on the formation of ion-pair complexes with the acidic sulfophthalein dyes bromocresol purple (BCP) and bromophenol blue (BPB) in pH 3.3 and 4.5 citrate-phosphate buffer, respectively. The formed complexes were extracted into dichloromethane, and their absorbance was measured at 403 and 410 nm for BCP and BPB, respectively. The second method was based on the charge transfer reaction of the drug as an n-electron donor with either 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) or 7,7,8,8-tetracyanoquinodimethane (TCNQ) as pi-acceptors, to give colored radical anions. The absorbances of products were measured at 457 nm in acetonitrile and 838 nm in methanol for DDQ and TCNQ, respectively. Under the optimum reaction conditions, Beer's law was obeyed with a good correlation coefficient (r = 0.9997-0.9999) in the concentration ranges 3.0-18.0, 3.0-20.0, 15.0-95.0, and 10.0-100.0 microg/mL for the BCP, BPB, DDQ, and TCNQ methods, respectively. Limits of detection of the BCP, BPB, DDQ, and TCNQ methods were 0.314, 0.408, 1.935, and 1.610 microg/mL, respectively. The limits of quantification were 1.045, 1.360, 6.449, and 5.367 microg/mL, respectively. The parameters molar absorptivity, precision, accuracy, recovery, robustness, and stability constant were studied. The proposed methods were successfully applied for determination of the drug in tablets with good accuracy and precision. Statistical comparison of the results with those obtained by a reported method showed good agreement and indicated no significant difference in accuracy and precision.
Asunto(s)
Doxazosina/análisis , Comprimidos/análisis , Antagonistas Adrenérgicos alfa/análisis , Púrpura de Bromocresol , Azul de Bromofenol , Indicadores y Reactivos , Iones , Metanol , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría/métodos , Espectrofotometría Infrarroja/métodosRESUMEN
A new, simple and sensitive spectrofluorimetric method has been developed for the determination of oseltamivir phosphate (OSP) in capsules. The method is based on the reaction between oseltamivir and fluorescamine in borate buffer solution of pH 8.50 to give highly fluorescent derivatives that are measured at 483 nm using an excitation wavelength of 381. The different experimental parameters effecting the development and stability of the reaction product were carefully studied and optimized. The fluorescence intensity concentration plot is rectilinear over the range 50-450 ng mL(-1) with a lower detection limit (LOD) of 1.219 ng mL(-1) and limit of quantitation (LOQ) of 4.064 ng mL(-1). Selectivity was validated by subjecting stock solution of OSP to acidic, basic, oxidative, and thermal degradation. No interference was observed from excipients present in formulations. The developed method was successfully applied to determination of the drug in capsules. The mean % recovery (n = 6) was 100.08. The results obtained were in good agreement with those obtained using a reported spectrophotometric method.
Asunto(s)
Fluorescamina/química , Oseltamivir/análisis , Cápsulas/química , Concentración de Iones de Hidrógeno , Conformación Molecular , Espectrometría de Fluorescencia/instrumentación , Espectrometría de Fluorescencia/métodos , Espectrofotometría Ultravioleta , Temperatura , Factores de TiempoRESUMEN
A new rapid and sensitive procedure assay is proposed for the spectrophotometric determination of tianeptine. The developed method involves formation of colored chloroform extractable ion-pair complexes of tianeptine with bromophenol blue (BPB), bromocresol green (BCG), bromothymol blue (BTB) and methyl orange (MO) in acidic medium. Beer's law is obeyed in the concentration ranges 3.0-12.0, 4.0-16.0, 4.0-14.0 and 2.0-10.0 microg ml(-1) with BPB, BCG, BTB and MO, respectively. The detection limit of tianeptine was found to be 1.8 microg ml(-1) for BPB, 2.0 for BCG, 2.0 microg ml(-1) for BTB and 1.0 microg ml(-1) for MO. Validation of the method was performed in terms of linearity, limit of detection (LOD), quantification (LOQ), accuracy and precision. Common excipients used as additives in pharmaceutical preparations do not interfere in the proposed method. The proposed method has been applied to determination of the examined drugs in pharmaceutical formulations and the results demonstrated that the method is equally accurate, precise, and reproducible as the official method. The t-test showed no significant difference at 95% confidence level.
Asunto(s)
Antidepresivos Tricíclicos/análisis , Tiazepinas/análisis , Química Farmacéutica , Concentración de Iones de Hidrógeno , Indicadores y Reactivos , Estándares de Referencia , Reproducibilidad de los Resultados , Solventes , Espectrofotometría Ultravioleta , Comprimidos , TemperaturaRESUMEN
A new sterol glucoside, (24R)-5 alpha-stigmast-9-(11)-en-3beta-D-glucopyranoside (1) has been isolated from a methanol extract of the red alga Gracilaria verrucosa, while cholesterol and (Z)-9-hexadecenoic acid (palmitoleic acid) have been isolated from a dichloromethane-acetone extract of the same alga. Additionally, an oily fraction of a dichloromethane-acetone extract has been investigated by gas chromatography/mass spectrometry (GC/MS). The main components in the oily fraction were heneicosanoic acid (49.8%), (Z)-9-octadecenoic acid (15.8%), and 15-tetracosenoic acid (15.6%) in addition to a few hydrocarbons, simple aromatics and a new compound, namely 3,4-dimethyl-5-carboxyclic acid-1-oxacyclopent-3-en-2-one. The structures of the isolated compounds have been elucidated by spectroscopic methods.
Asunto(s)
Gracilaria/química , 4-Butirolactona/análogos & derivados , Ácidos Grasos/química , Ácidos Grasos/aislamiento & purificación , Ácidos Grasos Monoinsaturados/química , Ácidos Grasos Monoinsaturados/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Glucósidos , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Estereoisomerismo , Estigmasterol/análogos & derivadosRESUMEN
Three sensitive, selective, accurate spectrophotometric and spectrofluorimetric methods have been developed for the determination of ropinirole hydrochloride in tablets. The first method was based on measuring the absorbance of drug solution in methanol at 250 nm. The Beer's law was obeyed in the concentration range 2.5-24 microg ml(-1). The second method was based on the charge transfer reaction of drug, as n-electron donor with 7,7,8,8-tetracyanoquinodimethane (TCNQ), as pi-acceptor in acetonitrile to give radical anions that are measured at 842 nm. The Beer's law was obeyed in the concentration range 0.6-8 microg ml(-1). The third method was based on derivatization reaction with 4-chloro-7-nitrobenzofurazan (NBD-Cl) in borate buffer of pH 8.5 followed by measuring the fluorescence intensity at 525 nm with excitation at 464 nm in chloroform. Beer's law was obeyed in the concentration range 0.01-1.3 microg ml(-1). The derivatization reaction product of drug with NBD-Cl was characterized by IR, 1H NMR and mass spectroscopy. The developed methods were validated. The following analytical parameters were investigated: the molar absorptivity (epsilon), limit of detection (LOD, microg ml(-1)) and limit of quantitation (LOQ, microg ml(-1)), precision, accuracy, recovery, and Sandell's sensitivity. Selectivity was validated by subjecting stock solution of ropinirole to acidic, basic, oxidative, and thermal degradation. No interference was observed from common excipients present in formulations. The proposed methods were successfully applied for determination of drug in tablets. The results of these proposed methods were compared with each other statistically.
Asunto(s)
Agonistas de Dopamina/análisis , Indoles/análisis , Espectrometría de Fluorescencia/métodos , Espectrofotometría/métodos , Comprimidos/análisis , Acetonitrilos/química , Benzofuranos/química , Boratos/química , Tampones (Química) , Calibración , Cloroformo/química , Agonistas de Dopamina/química , Concentración de Iones de Hidrógeno , Indoles/química , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Metanol/química , Estructura Molecular , Nitrilos/química , Fosfatos/química , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Two simple and sensitive extractive spectrophotometric methods have been developed for determination of zolmitriptan (ZTP) in tablets. These methods are based on the formation of yellow ion-pair complexes between ZTP and tropaeolin OO (TPOO) and bromothymol blue (BTB) in citrate-phosphate buffer of pH 4.0 and 6.0, respectively. The formed complexes were extracted with dichloromethane and measured at 411.5 and 410 nm for TPOO and BTB, respectively. The best conditions of the reactions were studied and optimized. Beer's law was obeyed in the concentration ranges of 2-20 and 1.5-17 microg/mL with molar absorptivities of 1.42 x 10(4) and 1.60 x 10(4) L/mol/cm for the TPOO and BTB methods, respectively. Correlation coefficients were 0.9998 and 0.9999 for TPOO and BTB methods, respectively. Limits of detection of the TPOO and BTB methods were 0.341 and 0.344 microg/mL, respectively, and the limits of quantitation were 1.034 and 1.051 microg/mL, respectively. Sandell's sensitivity and stability constant were also calculated. The proposed methods have been applied successfully for the analysis of the drug in its dosage forms. No interference was observed from excipients present in tablets. Statistical comparison of the results with those obtained by a high-performance liquid chromatography method showed excellent agreement and indicated no significant differences in accuracy and precision.
Asunto(s)
Técnicas de Química Analítica/métodos , Oxazolidinonas/análisis , Agonistas de Receptores de Serotonina/análisis , Espectrofotometría/métodos , Comprimidos/química , Triptaminas/análisis , Compuestos Azo/farmacología , Azul de Bromotimol/análisis , Cromatografía Líquida de Alta Presión/métodos , Concentración de Iones de Hidrógeno , Cloruro de Metileno/análisis , Modelos Químicos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Solventes/química , Espectrofotometría Ultravioleta/métodosRESUMEN
A new phenolic ester 2-( p-hydroxyphenyl)ethyl eicosaheptanoic acid ester (1) and a known one hexacosylferulate (2) were isolated from the acetone extract of Salvia microphylla. In addition, two sesquiterpenes beta-eudesmol (3) and 8alpha-hydroxy-beta-eudesmol (4), a diterpene carnosic acid 12-methyl ether (12-methoxycarnosic acid) (5), three triterpenes erithrodiol 3-acetate, oleanolic acid, lupeol and beta-sitosterol were obtained as known compounds from this plant extract. The structures of the isolated compounds were elucidated by spectroscopic methods, including one- and two- dimensional 1H- and 13C-NMR and MS spectroscopies. The selected compounds were tested for antimicrobial activity against standard bacterial strains, and only carnosic acid 12-methyl ether showed antimicrobial activity against S. aureus at 78 microg mL(-1).
Asunto(s)
Ésteres/aislamiento & purificación , Fenoles/aislamiento & purificación , Salvia/química , Terpenos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Sitoesteroles/aislamiento & purificaciónRESUMEN
A new sesquiterpene (1), and a halogenated C15 acetogenin (2), a stereoisomer of neoisoprelaurefucin were isolated from Laurencia obtusa. Four known compounds laurencienyne (3), rogiolenyne B (4), obtusenol (5), and (3E)-dactomelyne (6) were also isolated from this alga. Rogiolenyne B (4) and (3E)-dactomelyne (6) were found for the first from this species. The structures of these compounds were elucidated by spectroscopic methods. The unambiguous assignments of the 1H and 13C NMR spectral data of (5) and 13C NMR data of (6) were also reported for the first time.
Asunto(s)
Alcoholes Grasos/química , Alcoholes Grasos/aislamiento & purificación , Lactonas/química , Lactonas/aislamiento & purificación , Laurencia/química , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Acetogeninas , Halógenos/química , Laurencia/metabolismo , Espectroscopía de Resonancia MagnéticaRESUMEN
Four new sesquiterpenes, (8R)-8-bromo-10-epi-beta-snyderol (1), (8S)-8-bromo-beta-snyderol (2), 5-bromo-3-(3'-hydroxy-3'-methylpent-4'-enylidene)-2,4,4-trimethylcyclohexanone (3), and the epoxide 4, have been isolated from the chloroform-methanol extract of Laurencia obtusa, together with the three known compounds alpha-snyderol (5), alpha-snyderol acetate (6), and stigmasterol. The structures of the isolated compounds were elucidated through spectroscopic analyses. Compound 1 showed antimalarial activity, with IC(50) values of 2700 and 4000 ng/mL against the D6 and W2 clones of Plasmodium falciparum, respectively.
Asunto(s)
Antimaláricos/aislamiento & purificación , Hidrocarburos Bromados/aislamiento & purificación , Laurencia/química , Plasmodium falciparum/efectos de los fármacos , Sesquiterpenos/aislamiento & purificación , Animales , Antimaláricos/química , Antimaláricos/farmacología , Hidrocarburos Bromados/química , Hidrocarburos Bromados/farmacología , Concentración 50 Inhibidora , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos/farmacología , Estereoisomerismo , Estigmasterol/química , Estigmasterol/aislamiento & purificación , TurquíaRESUMEN
A new ursane-type triterpenoid, 3 beta,11 alpha,21 alpha-trihydroxyurs-12-ene, named salvistamineol (1), has been isolated from the methanol extract of Salvia staminea. In addition to 1, the methanol extract yielded four known compounds and the acetone extract yielded twelve known compounds consisting of two sesquiterpenes, six diterpenoids, a triterpenoid, two steroids and one flavone. DNA damaging properties of the extracts and some isolated diterpenes were investigated against three yeasts and only taxodione gave a positive response and also showed the highest cytotoxic activity against a panel of cell lines among the investigated compounds in this study.
Asunto(s)
Antineoplásicos/farmacología , Diterpenos/farmacología , Fitoterapia , Extractos Vegetales/farmacología , Salvia , Triterpenos/farmacología , Levaduras/efectos de los fármacos , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Diterpenos/administración & dosificación , Diterpenos/química , Diterpenos/uso terapéutico , Humanos , Concentración 50 Inhibidora , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Triterpenos/administración & dosificación , Triterpenos/química , Triterpenos/uso terapéutico , Células Tumorales Cultivadas/efectos de los fármacosRESUMEN
Bioassay-directed fractionation of an extract prepared from the dried leaves and stem barks of Ficus fistulosa Reinw. ex Blume (Moraceae) led to the isolation of verrucarin L acetate (1), together with 3alpha-hydroxyisohop-22(29)-en-24-oic acid, 3beta-gluco-sitosterol, 3,4-dihydro-6,7-dimethoxyisocarbostyril, 3,4,5-trimethoxybenzyl alcohol, alpha-methyl-3,4,5-trimethoxybenzyl alcohol, indole-3-carboxaldehyde, palmanine, and aurantiamide acetate. Roridin E (2) was identified in a subfraction from the dried leaves and stems of Rhaphidophora decursiva Schott (Araceae). Verrucarin L acetate and roridin E were characterized as macrocyclic trichothecene sesquiterpenoids and found to inhibit the growth of Plasmodium falciparum with IC 50 values below 1 ng/ml.