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1.
J Asian Nat Prod Res ; : 1-7, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38572987

RESUMO

A new triterpenoid saponin (1), along with five known compounds (2-6), was isolated from Bupleurum marginatum Wall. ex DC, of which compounds 2-4 were obtained for the first time from this plant. The structures were confirmed by the analysis of 1D, 2D NMR, and HR-ESIMS data, and comparison with previous spectral data. Anti-liver fibrotic activities of the isolates were determined as proliferation inhibition of LPS-induced activation of HSC-T6 in vitro.

2.
Zhongguo Zhong Yao Za Zhi ; 48(3): 707-714, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36872234

RESUMO

Chemical constituents in soft coral Sarcophyton glaucum were separated and purified by various chromatographic methods. Based on the spectral data, physicochemical properties, and comparison with the data reported in the literature, nine cembranoids, including a new cembranoid named sefsarcophinolide(1) together with eight known cembranoids, namely(+)-isosarcophine(2), sarcomilitatin D(3), sarcophytonolide J(4),(1S,3E,7E,13S)-11,12-epoxycembra-3,7,15-triene-13-ol(5), sarcophytonin B(6),(-)-eunicenone(7), lobophytin B(8), and arbolide C(9), were identified. As revealed by biological activity experiment results, compounds 2-6 had weak acetylcholinesterase inhibitory activity, and compound 5 displayed weak cytotoxicity against K562 tumor cell line.


Assuntos
Antozoários , Animais , Acetilcolinesterase , Linhagem Celular Tumoral
3.
Nat Prod Res ; 37(20): 3380-3387, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35574628

RESUMO

Two new triterpenoid saponins (1 and 2), together with two known saponins (3 and 4) were isolated from Bupleurum marginatum Wall. ex DC. Their structures were elucidated by the comprehensive spectroscopic analysis. Compounds 1 and 2 represented the rare example of an oleanane-type triterpenoid with two sugar moieties at C-3 and C-28. The cytotoxic activity of four compounds was evaluated against normal heptocell BRL-3A in vitro.

4.
J Asian Nat Prod Res ; 24(1): 88-95, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33533666

RESUMO

A new polychiral bisabolane sesquiterpene, bisabolanoic acid A (1), was isolated from the mangrove-derived fungus Colletotrichum sp. SCSIO KcB3-2. Its planar structure was identified on the basis of spectroscopic data analysis (HRESIMS, 1D, and 2D NMR), and the absolute configurations of three chiral carbons were determined by experimental and calculated electronic circular dichroism (ECD) and optical rotatory dispersion (ORD), together with Mo2(OAc)4-induced ECD methods. Bisabolanoic acid A (1) showed moderate inhibitory activity against acetylcholinesterase (AChE) with IC50 value of 2.2 µM, and the in silico molecular docking was also performed.


Assuntos
Inibidores da Colinesterase , Colletotrichum , Rhizophoraceae/microbiologia , Sesquiterpenos , Acetilcolinesterase , China , Colletotrichum/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Sesquiterpenos/farmacologia
5.
J Asian Nat Prod Res ; 23(12): 1156-1163, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33334190

RESUMO

Two new 2-(2-phenylethyl)chromone derivatives (1-2) were isolated from the ethyl acetate extract of artificial agarwood induced by holing method originating from Aquilaria sinensis (Lour.) Gilg, and they were isolated from this genus for the first time. The structures of these two new compounds were elucidated by extensive spectroscopic analyses, including UV, IR, one- and two-dimensional NMR and HRESIMS measurements. Bioassay tests of these two new compounds showed compounds 1 and 2 had weak inhibitory activity against acetylcholinesterase at a concentration of 50.0 µg/ml.


Assuntos
Acetilcolinesterase , Thymelaeaceae , Inibidores da Colinesterase/farmacologia , Flavonoides , Estrutura Molecular , Madeira
6.
Medicine (Baltimore) ; 99(23): e20646, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32502051

RESUMO

It is critical to accurately identify patients with severe acute pancreatitis (SAP) in a timely manner. This study aimed to develop a new simplified AP scoring system based on data from Chinese population.We retrospectively analyzed a consecutive series of 585 patients diagnosed with SAP at the Changhai hospital between 2009 and 2017. The new Chinese simple scoring system (CSSS) was derived using logistic regression analysis and was validated in comparison to 4 existing systems using receiver operating characteristic curves.Six variables were selected for incorporation into CSSS, including serum creatinine, blood glucose, lactate dehydrogenase, heart rate, C-reactive protein, and extent of pancreatic necrosis. The new CSSS yields a maximum total score of 9 points. The cut-offs for predicting mortality and severity (discriminating moderately SAP from SAP) were set as 6 points and 4 points respectively. Compared with 4 existing scoring systems, the area under the receiver operating characteristic of CSSS for prediction of mortality was 0.838, similar to acute physiology and chronic health evaluation II (0.844) and higher than Ranson's score (0.702, P < .001), bedside index of severity in acute pancreatitis (0.615), and modified computed tomography severity index (MCTSI) (0.736). For predicting SAP severity, CSSS was the most accurate (0.834), followed by acute physiology and chronic health evaluation II (0.800), Ranson's score (0.702), MCTSI (0.660), and bedside index of severity in acute pancreatitis (0.570). Further, the accuracy of predicting pancreatic infection with CSSS was the highest (0.634), similar to that of MCTSI (0.641).A new prognostic scoring system for SAP was derived and validated in a Chinese sample. This scoring system is a simple and accurate method for prediction of mortality.


Assuntos
Pancreatite Necrosante Aguda/mortalidade , Adulto , Idoso , Biomarcadores/sangue , Glicemia/metabolismo , Proteína C-Reativa/análise , China/epidemiologia , Creatinina/sangue , Feminino , Humanos , L-Lactato Desidrogenase/sangue , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pancreatite Necrosante Aguda/sangue , Valor Preditivo dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença
7.
J Dig Dis ; 20(12): 656-662, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31618520

RESUMO

OBJECTIVE: We conducted a randomized trial aiming at improving patients' informed consent for undergoing endoscopic retrograde cholangiopancreatography (ERCP) in clinical care by comparing the efficacy of an additional educational video to written informed consent with that of written informed consent alone. METHODS: This was a single-center, randomized controlled trial. Consecutive patients undergoing ERCP were randomized to a video education or a control group. An educational video detailing ERCP procedure plus standard written informed consent was administered to the video education group, while the control group reviewed standard written informed consent only. The primary outcome was the patients' perception of the risk or possibility of ERCP complications. Their perception of the benefits of ERCP, alternative treatments and overall satisfaction with the process of informed consent were also compared. RESULTS: In total 205 patients were included in the study (104 in the control group and 101 in the video education group). Patients' comprehension of ERCP-related complications in the video education group was significantly increased (P < 0.001), and these patients were more likely to correctly identify the incidence of such complications. Significantly more patients in the video education group were very satisfied with informed consent process (87.1% vs 76.0%, P = 0.040) and fewer patients needed additional explanations (31.7% vs 47.1%, P = 0.024). CONCLUSIONS: A supplementary educational video could greatly improve patient's understanding of ERCP procedure, in particular, its potential risks and complications, as well as their overall satisfaction with the process of informed consent (ClinicalTrials.gov no. NCT02810379).


Assuntos
Recursos Audiovisuais , Colangiopancreatografia Retrógrada Endoscópica , Consentimento Livre e Esclarecido , Educação de Pacientes como Assunto/métodos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Compreensão , Feminino , Humanos , Consentimento Livre e Esclarecido/psicologia , Consentimento Livre e Esclarecido/normas , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Melhoria de Qualidade , Medição de Risco , Gestão de Riscos/legislação & jurisprudência , Gestão de Riscos/métodos , Gestão de Riscos/normas
8.
Biosens Bioelectron ; 100: 565-570, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29024921

RESUMO

Polydopamine (PDA) can be formed by monomeric self-polymerization in water. This convenient behavior was exploited to prepare a molecularly imprinted polymer (MIP) layer on the surface of multi-walled carbon nanotubes (MWCNTs) with sunset yellow (SY) as a template molecule. The prepared nanocomposites were characterized, and their electrochemical behavior towards SY was investigated. Under the optimized conditions, a glassy carbon electrode modified with the imprinted nanocomposite showed a highly selective and ultrasensitive electrochemical response to SY compared with the performance of control electrodes and previously reported electrochemical sensors for SY. The improved behavior of the developed sensor can be attributed to its superficial highly matched imprinted cavities on the excellent electrocatalytic matrix of MWCNTs and the electronic barrier of the non-imprinted PDA to outside molecules. The fabricated sensor expressed a linear relationship to SY concentrations from 2.2nM to 4.64µM with a detection limit of 1.4nM (S/N = 3). The sensor also exhibited excellent selectivity for SY over its structural analogs, good stability, and adequate reproducibility. The prepared sensor was successfully used to detect SY in real spiked samples. This methodology has potential application value and may be readily adapted to design other PDA-based MIP sensors.


Assuntos
Compostos Azo/análise , Corantes/análise , Técnicas Eletroquímicas/métodos , Indóis/química , Impressão Molecular/métodos , Nanotubos de Carbono/química , Polímeros/química , Análise de Alimentos/métodos , Limite de Detecção , Reprodutibilidade dos Testes
9.
Arch Pharm Res ; 40(4): 429-434, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25149903

RESUMO

Three new glycoalkaloids, N-formyl-asimilobine-2-O-ß-D-glucoside (1), (-)-1-O-ß-D-glucoside-8-oxotetrahydropalmatine (2), and 1-N-monomethylcarbamate-argentinine-3-O-ß-D-glucoside (3) were isolated from tubers of Stephania succifera. The structures were established based on spectroscopic analysis, and the antimicrobial activities of the three glycoalkaloids are reported.


Assuntos
Alcaloides/farmacologia , Antibacterianos/farmacologia , Candida albicans/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Stephania/química , Alcaloides/química , Alcaloides/isolamento & purificação , Antibacterianos/química , Antibacterianos/isolamento & purificação , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade
10.
Nat Prod Commun ; 11(5): 573-5, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27319119

RESUMO

One new monoterpenoid, nerol oxide-8-carboxylic acid (1), and one new flavonoid glycoside, claulansoside A (2), together with six known compounds, clausenamide (3), quercetin (4), isorhamnetin (5), dihydromyric (6), 2",3"-dihydroxyanisolactone (7) and (E,E)-8-(7-hydroxy-3,7-dimethylocta-2,5-dienyloxy)psoralen (8), have been isolated from the peels of Clausena lansium (Lour.) Skeels. Their structures were determined using a combination of 1D, and 2D NMR (HMQC, HMBC, COSY and NOESY) techniques, and HR-ESI-MS analyses. Compounds 1 and 7 exhibited antibacterial activity against Staphylococcus aureus with the diameter of inhibition zones of 11.5 mm and 14.2 mm. Compounds 3 and 6 showed α-glucosidase inhibitory activity in vitro.


Assuntos
Clausena/química , Flavonoides/isolamento & purificação , Monoterpenos/isolamento & purificação , Monoterpenos Acíclicos , Flavonoides/química , Frutas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Monoterpenos/química
11.
Nat Prod Commun ; 11(3): 369-70, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27169183

RESUMO

A new degraded sesquiterpene, tectoionol C (1), together with five known compounds wilsonol F (2), heterodendrin (3), epi-heterodendrin (4), 7-deoxogeayine (5), and 1H-indole-3-carboxylicacid, methyl ester (6), was isolated from the twigs of Trigonostemon lutescens. Their structures were determined by spectroscopic methods including 1D and 2D NMR techniques, as well as by comparison with published data.


Assuntos
Euphorbiaceae/química , Sesquiterpenos/química , Modelos Moleculares , Estrutura Molecular
12.
Biosens Bioelectron ; 78: 31-36, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26584080

RESUMO

New techniques are required for the rapid and sensitive detection of Escherichia coli O157:H7 (E. coli O157:H7), a pathogenic bacterium responsible for serious and sometimes life-threatening diseases in humans. In this study, we developed a highly sensitive and efficient biosensor for the quantitative detection of E. coli O157:H7 by integrating fluorescein-releasable biolabels with a magnetism-separable probe. Hollow silica nanospheres with a diameter of approximately 350 nm were synthesized, enriched with fluorescein, and surface-protected with macromolecule layers of poly (acrylic acid) and poly (dimethyldiallylammonium chloride). These fluorescein-enriched hollow silica nanospheres were characterized using scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. They were further functionalized as immune labels of E. coli O157:H7 for a sandwich-type immune reaction between this bacterium and magnetic nanoparticles (Fe3O4@SiO2). Next, the E. coli O157:H7 cells were captured, magnetically separated, and quantified based on the fluorescence intensity of the fluorescein released from the biolabels of the fluorescein-enriched hollow silica nanospheres. This analytic process can be completed within 75 min, and the biosensor showed a linear relationship ranging from 4 to 4.0 × 10(8)cfu/mL with a detection limit of 3 cfu/mL. These results show that the developed fluorescent sensor has excellent specificity, and good reproducibility and stability. This study used real spiked samples for detection, indicating that this technique has a wide range of potential applications and may be readily adapted for detecting other pathogens.


Assuntos
Técnicas Biossensoriais/métodos , Escherichia coli O157/isolamento & purificação , Nanosferas/química , Dióxido de Silício/química , Escherichia coli O157/patogenicidade , Fluoresceína/química , Fluorescência , Humanos , Limite de Detecção
13.
J Asian Nat Prod Res ; 17(3): 280-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25492303

RESUMO

A new eremophilane sesquiterpene, sporogen AO-2 (1), and a new beyerane diterpene, thecacorin C (2), together with two known compounds, longifoamide-B (3) and methylcholestane-3ß,5α,6ß-triol (4), were isolated from the stems of Manihot esculenta. The structures of the two new compounds were determined by spectroscopic techniques (UV, IR, MS, 1D, and 2D NMR). Antimicrobial assay showed that compound 3 possessed modest inhibitory effects on Saphylococcus aureus and methicillin-resistant S.aureus, diameters of inhibition zones of which were 7.5 and 8.0 mm, respectively. Compound 4 possessed modest inhibitory effect on S. aureus, the diameter of inhibition zone of which was 6.8 mm.


Assuntos
Antibacterianos/isolamento & purificação , Diterpenos/isolamento & purificação , Manihot/química , Antibacterianos/química , Antibacterianos/farmacologia , Diterpenos/química , Diterpenos/farmacologia , Resistência a Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Caules de Planta/química , Sesquiterpenos/farmacologia
14.
Arch Pharm Res ; 38(5): 673-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25060947

RESUMO

Two new sesquiterpenoids, named 2α-hydroxyxylaranol B (1) and 4ß-hydroxyxylaranol B (2), together with a known diterpenoid 3,4-seco-sonderianol (3) were isolated from the fermentation of endophytic fungus J3 of Ceriops tagal. Their structures were elucidated based on spectroscopic methods including 1D and 2D NMR (HMQC, (1)H-(1)H COSY and HMBC). All compounds were evaluated for their cytotoxic activities by MTT method, and compound 3 exhibited cytotoxic activities against K562, SGC-7901, and BEL-7402 cell lines.


Assuntos
Endófitos/isolamento & purificação , Fungos/isolamento & purificação , Folhas de Planta , Rhizophoraceae , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Citotoxinas/química , Citotoxinas/isolamento & purificação , Humanos , Células K562
15.
J Dig Dis ; 15(7): 377-85, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24720587

RESUMO

OBJECTIVE: We aimed to identify the risk factors for predicting pancreatic infection in patients with severe acute pancreatitis (SAP). METHODS: In all, 163 patients with SAP were included and divided into two groups based on the presence or absence of pancreatic infection. Their demographic and clinical characteristics, laboratory examination results, complications and treatment modalities were collected from their medical records. Variables were initially screened by univariate analysis and those with statistical significance were then filtered by multivariate analysis to determine the independent risk factors for pancreatic infection in SAP. RESULTS: Patients having SAP with pancreatic infection had a lower partial pressure of arterial carbon dioxide (PaCO2 ), peripheral white blood cell count and alkaline phosphatase levels, together with a higher computed tomography severity index (CTSI) than those without pancreatic infection, while their lactate dehydrogenase (LDH) levels and blood urea nitrogen were much higher. Pancreatic infection was also more common in patients receiving late fluid resuscitation than in those receiving early fluid resuscitation. Multivariate analyses revealed that increased LDH level, high CTSI, delayed fluid resuscitation and hypoxemia were independent risk factors for pancreatic infection in SAP. The sensitivity, specificity, positive and negative predictive values for a model combining the parameters in predicting pancreatic infection were 84%, 97%, 88% and 96%, respectively, with a cut-off value of 0.393, and the area under the receiver operating characteristic curve was 0.923. CONCLUSION: Increased LDH, high CTSI, delayed fluid resuscitation and hypoxemia are independent risk factors for predicting pancreatic infection in patients with SAP.


Assuntos
Infecções Bacterianas/complicações , Infecções Oportunistas/complicações , Pancreatite Necrosante Aguda/complicações , Adulto , Idoso , Antibacterianos/uso terapêutico , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/tratamento farmacológico , Biomarcadores/sangue , Dióxido de Carbono/sangue , Feminino , Humanos , Hipóxia/complicações , L-Lactato Desidrogenase/sangue , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/diagnóstico , Infecções Oportunistas/tratamento farmacológico , Oxigênio/sangue , Pressão Parcial , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
16.
Nat Prod Commun ; 9(1): 7-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24660448

RESUMO

One new diterpenoid, 11alpha,12betaH-dolabella-4,8(17)-dien-3alpha,7beta,18-triol (1) and one new sesquilignan, 9-methoxy-7',8'-cis-7",8"-cis-buddlenol B (2), together with three known compounds, (+)-diasyringaresinol (3), N-methyl-5- hydroxy-delta3-pyrrolin-2-one (4) and marmin (5), have been isolated from Aglaia odorata var. microphyllina. Their structures were determined using 1D and 2D NMR spectroscopy. Compound 1 exhibited cytotoxic activity against the K562 cell line with an IC50 value of 12.5 microg/mL.


Assuntos
Aglaia/química , Diterpenos/isolamento & purificação , Diterpenos/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células K562 , Estrutura Molecular , Plantas Medicinais/química
17.
Molecules ; 18(10): 12324-45, 2013 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-24108398

RESUMO

Agarwood is the fragrant resinous heartwood obtained from certain trees in the genus Aquilaria belonging to the family Thymelaeaceae. 2-(2-Phenylethyl)chromones and characteristic sesquiterpenes are the main classes of aromatic compounds isolated from agarwood. Although there are many sesquiterpenes, relatively few 2-(2-phenylethyl)chromones have been determined in agarwood by GC-MS. After analysis of the MS spectra of eighteen 2-(2-phenylethyl)chromone derivatives isolated from agarwood and identified by NMR spectroscopy, together with the reported MS data and characteristic of structures of 2-(2-phenylethyl)chromones, the MS characterization, fragmentation patterns and characteristic fragment peaks for the compounds were deduced and a table summarizing MS characterization of 2-(2-phenylethyl)chromones in agarwood is presented. All the 2-(2-phenylethyl)chromones previously reported in agarwood are substituted by methoxy or/and hydroxy groups, except for one compound. Due to the fact they all possess the same basic skeleton (molecular weight: 250) and similar substituent groups (methoxy or hydroxy groups), a formula (30m + 16n = MW - 250) is provided to calculate the number of methoxy (m) or hydroxy (n) groups according to molecular ion peak or molecular weight (MW). We deduced that the characteristic fragmentation behaviors of the 2-(2-phenylethyl)chromones are the cleavages of the CH2-CH2 bond between chromone moiety and phenyl moiety. Thus, characteristic fragment ions, such as m/z 91 [C7H7], 107 [C7H6+OH], 121 [C7H6+OCH3], 137 [C7H5+OH+OCH3] are formed by different substituted benzyl moieties, while characteristic fragment ions such as m/z 160 [C10H8O2], 176 [C10H7O2+OH], 190 [C10H7O2+OCH3], 220 [C10H6O2+OCH3×2] are formed by different substituted chromone moieties. Furthermore, rules regarding to the relationship between the positions of hydroxy or methoxy groups and the relative abundances of benzyl and chromone fragment ions have been deduced. Elucidation of how the positions of hydroxy or methoxy groups affect the relative abundances of benzyl and chromone fragment peaks is also provided. Fifteen unidentified compounds of an artificial agarwood sample analyzed by GC-MS, were preliminary determined as 2-(2-phenylethyl)chromones by analysis of their MS characterization and by comparison of their MS spectra with those of 18 standard compounds or 2-(2-phenylethyl)chromones reported in literature according to the above-mentioned methods and rules. This report will be helpful for the analysis and structural elucidation of 2-(2-phenylethyl)chromones in agarwood by GC-MS, and provides fast and reliable characterization of the quality of agarwood.


Assuntos
Flavonoides/química , Thymelaeaceae/química , Madeira/química , Fracionamento Químico , Flavonoides/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Peso Molecular , Ácido Palmítico/química , Ácido Palmítico/isolamento & purificação , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação
18.
Planta Med ; 79(14): 1329-34, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23929247

RESUMO

Five new 2-(2-phenylethyl)chromone derivatives, qinanones A-E (1-5), together with eight known 2-(2-phenylethyl)chromone derivatives (6-13), were isolated from the Et2O extract of high-quality Chinese agarwood "Qi-Nan" originating from Aquilaria sinensis. The structures of the new 2-(2-phenylethyl)chromones were elucidated by spectroscopic techniques (UV, IR, 1D and 2D NMR) and MS analyses. In the bioassay for acetylcholinesterase inhibitors, compounds 1-6, 10, and 12 exhibited weak inhibitory activities (inhibition percentage ranged from 10 % to 24 % at the concentration of 50 µg/mL). Compared with other agarwoods, "Qi-Nan" was different in containing 2-(2-phenylethyl)chromones with unsubstituted chromone rings.


Assuntos
Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Flavonoides/isolamento & purificação , Thymelaeaceae/química , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Estrutura Molecular , Qi
19.
J Asian Nat Prod Res ; 15(8): 899-904, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23796077

RESUMO

Two new acridone alkaloids, 3-methoxy-1,4,5-trihydroxy-10-methylacridone (1) and 2,3-dimethoxy-1,4,5-trihydroxy-10-methylacridone (2), were isolated from the ethanol extract of the branch of Atalantia buxifolia. Their structures were elucidated by spectroscopic methods including 1D and 2D NMR. Compounds 1 and 2 exhibited significant antibacterial activity against Staphylococcus aureus and weak inhibitory effect on acetylcholinesterase.


Assuntos
Acridinas/isolamento & purificação , Acridinas/farmacologia , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Rutaceae/química , Acetilcolinesterase , Acridinas/química , Acridonas , Alcaloides/química , Antibacterianos/química , Inibidores da Colinesterase/química , Medicamentos de Ervas Chinesas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Staphylococcus aureus/efeitos dos fármacos
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(3): 636-41, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23705423

RESUMO

A white organic light-emitting device (WOLED) with a yellow phosphorescence material, bis[2-(4-tertbutylphenyl) benzothiazolato-N,C2 '] iridium (acetylacetonate) [(t-bt)2Ir(acac)], and two blue phosphorescence materials, iridium(Ill) bis (4', 6'-difluorophenylpyridinato) tetrakis(1-pyrazolyl) borate (FIr6) and bis[(4, 6-difluorophenyl)-pyridinato-N, C2 '] (picolinate) iridium (III) (FIrpic), were fabricated. Stable white emission was realized by using undoped ultrathin yellow emissive layer (EML), two doped blue EMLs together with the proper thickness of an interlayer confining the exciton. The WOLED performed pure white light emission with the Commissions Internationale de l'Eclairage (CIE) coordinates of (0.29+/-0.01, 0.34+/-0.01) from 6 to 14 V. Moreover, electroluminescence (EL) characteristics of the devices were also studied to verify the emissive mechanism from a phosphorescent system consisting of three iridium chelates. Also, the results showed that the triple-phosphor-element EMLs WOLED had lower efficiency roll-off owing to the stable recombination zone.

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