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2.
Sci Rep ; 14(1): 2928, 2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316909

RESUMO

The rising temperatures and levels of carbon dioxide in the atmosphere are anticipated to have a significant impact on the productivity of agricultural crops. Although, the individual effects of elevated CO2 and temperature have been extensively studied in C3 and C4 crops, there remains a scarcity of research investigating their interactive effects specifically on maize hybrids. The impact of elevated temperature and its interaction with elevated CO2 on phenology, physiology, biomass, and grain yield of maize hybrids was assessed in a field experiment using Free Air Temperature Elevation (FATE) facility. The results showed that elevated temperature (eT) increased the anthesis silking interval (ASI), while the presence of elevated CO2 along with elevated temperature (eT + eCO2) mitigated this effect. The differential expression were observed between hybrids depending on their genetic potential. Furthermore, the net photosynthetic rate (Anet), stomatal conductance (gs), and transpiration rate (Tr) of hybrids decreased under elevated temperature but eT + eCO2 condition helped in reverting its impact to some extent. In term of leaf composition, the highest level of total soluble sugars (TSS) and starch was observed under eT + eCO2 conditions, possibly due to improved Anet in the presence of elevated eCO2. The negative impact of eT was also evident through increased proline and MDA content, but eT + eCO2 ameliorated the adverse effect of eT. The biomass and grain yield also responded similarly, among the hybrids 900M GOLD recorded superior performance for grain yield at eT condition exceeding 35 °C. On the other hand, DHM117 experienced a significant reduction in grain yield under eT, but performed better under eT + eCO2 due to its improved physiological response to eCO2. The study indicated that elevated levels of carbon dioxide can actually mitigate the detrimental effects of elevated temperature on maize crop. This positive impact on maize crop can be attributed to an enhanced physiological performance in the presence of eCO2 which enables the plants to maintain satisfactory yield levels despite the challenging environmental conditions.


Assuntos
Dióxido de Carbono , Zea mays , Dióxido de Carbono/metabolismo , Temperatura , Fotossíntese/fisiologia , Grão Comestível/metabolismo , Produtos Agrícolas/metabolismo
3.
Sci Rep ; 13(1): 6788, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37100788

RESUMO

Gram pod borer, Helicoverpa armigera (Hub.) is the major insect pest of pigeonpea and prediction of number of generations (no. of gen.) and generation time (gen. time) using growing degree days (GDD) approach during three future climate change periods viz., Near (NP), Distant (DP) and Far Distant (FDP) periods at eleven major pigeonpea growing locations of India was attempted. Multi-model ensemble of Maximum (Tmax) and Minimum (Tmin) temperature data of four Representative Concentration Pathways viz., RCP 2.6, 4.5, 6.0 and 8.5 of Coupled Model Inter comparison Project 5 (CMIP5) models was adopted here. The increase in projected Tmax and Tmin are significant during 3 climate change periods (CCPs) viz., the NP, DP and FDP over base line (BL) period under four RCP scenarios at all locations and would be higher (4.7-5.1 °C) in RCP 8.5 and in FDP. More number of annual (10-17) and seasonal (5-8) gens. are expected to occur with greater percent increase in FDP (8 to 38%) over base line followed by DP (7 to 22%) and NP (5to 10%) periods with shortened annual gen. time (4 to 27%) across 4 RCPs. The reduction of crop duration was substantial in short, medium and long duration pigeonpeas at all locations across 4 RCPs and 3 CCPs. The seasonal no.of gen. is expected to increase (5 to 35%) with shortened gen. time (4 to 26%) even with reduced crop duration across DP and FDP climate periods of 6.0 and 8.5 RCPs in LD pigeonpea. More no. of gen. of H. armigera with reduced gen. time are expected to occur at Ludhiana, Coimbatore, Mohanpur, Warangal and Akola locations over BL period in 4 RCPs when normal duration of pigeonpeas is considered. Geographical location (66 to 72%), climate period (11 to 19%), RCPs (5-7%) and their interaction (0.04-1%) is vital and together explained more than 90% of the total variation in future pest scenario. The findings indicate that the incidence of H. armigera would be higher on pigeonpea during ensuing CCPs in India under global warming context.


Assuntos
Mudança Climática , Mariposas , Animais , Aquecimento Global , Temperatura , Índia
4.
Bull Entomol Res ; : 1-15, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34629126

RESUMO

Fall armyworm, Spodoptera frugiperda (J. E. Smith) is a polyphagous and highly destructive invasive insect pest of many crops. It was recently introduced into India and widely reported in almost all parts of India. Development of a temperature-based phenology model for predicting its rate of development and distribution will help in understanding the establishment and further spread of introduced invasive insect pests. Development, survival and reproduction parameters of S. frugiperda at six constant temperature conditions (15, 20, 25, 27, 30 and 35°C) were investigated and further validated with data generated under fluctuating temperature conditions. The estimated lower developmental threshold temperatures were 12.1°C for eggs, 11°C for larvae, 12.2°C for pupae, 15.13°C for males and 12.66°C for females. Degree-day (DD) requirements for the development of the different stages of S. frugiperda were 50, 250 and 200 DD for egg, larva and pupa, respectively. The best-fitted functions were compiled for each life stage to yield a phenology model, which was stochastically simulated to estimate the life table parameters. The developed phenology model predicted temperature ranges between 27 and 30°C as favourable for S. frugiperda development, survival and reproduction. The results revealed that maximum net reproductive rate (215.66 females/female/generation) and total fecundity (981.08 individuals/female/generation) were attained at 30°C constant temperature. The mean length of generations decreased from 74.29 days at 15°C to 38.74 days at 30°C. The maximum intrinsic rate of increase (0.138 females/female/day) and shortest doubling time (4.9 days) were also observed at 30°C. Results of simulated life table parameters showed high temperature-dependent development of S. frugiperda and complete development within all the tested constant temperature ranges (15-35°C). Simulated life table parameters for predicting risk indices of S. frugiperda in India indicated a significant increase in activity indices and establishment risk indices with a higher number of generations during future (2050 and 2070) climatic change scenarios compared to present conditions. Our results indicate that India will be highly suitable for the establishment and survival of S. frugiperda in future time periods.

5.
J Therm Biol ; 94: 102749, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33292990

RESUMO

Multi-model ensemble of Maximum (Tmax) and Minimum (Tmin) temperature data of four Representative Concentration Pathways viz., RCP 2.6, RCP 4.5, RCP 6.0 and RCP 8.5 of Coupled Model Intercomparison Project 5 (CMIP5) models were generated for ten major groundnut growing locations of the India to predict the number of generations of Spodoptera litura (Fab.) using Growing Degree Days approach during three future climate viz., Near (NF), Distant (DF) and Very Distant (VDF) periods and were compared over 1976-2005 baseline period (BL). Projections indicate significant increase in Tmax (0.7-4.7 °C) and Tmin (0.7-5.1 °C) in NF, DF and VDF periods under the four RCP scenarios at the ten groundnut growing locations. Higher percent increase of the number of generations of S. litura was predicted to occur in VDF (6-38%) over baseline, followed by DF (5-22%) and NF (4-9%) periods with reduction of generation time (5-26%) across the four RCP scenarios. Reduction of crop duration was higher (12-22 days) in long duration groundnut than in medium and short duration groundnut. Decrease in crop duration was higher in VDF (12.1-20.8 days) than DF (8.26-13.15 days) and NF (4.46-6.15 days) climate change periods under RCP 8.5 scenario. Increase in number of generations of S. litura was predicted even with altered crop duration of groundnut. Among locations, more number of generations of S. litura with reduced generation time are likely at Vridhachalam and Tirupathi locations. Geographical location (74-77%) and climate period (15-19%), together explained over 90 percent of the total variation in the number of generations and generation time of S. litura. These findings suggest that the incidence of S. litura on groundnut could be higher in future.


Assuntos
Arachis/parasitologia , Mudança Climática , Interações Hospedeiro-Parasita , Modelos Teóricos , Spodoptera/fisiologia , Animais , Temperatura
6.
Bioorg Med Chem Lett ; 26(6): 1639-1644, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26873415

RESUMO

A series of new indole-2-carboxylic acid derived mono and bis 1,4-disubstituted 1,2,3 triazoles (I(1)-I(6) and I(7)-I(12)) were synthesized and screened for their anticancer (in vitro and in vivo), antibacterial, and DNA cleavage activities. All the synthesized compounds were characterized by spectral studies. The in vitro anticancer screening results revealed that compound I(12) has registered potential activity against MCF-7, HeLa and HEK293 as compared with the standard reference drug Cisplatin. Remaining compounds have exhibited moderate to good activity against three cancer cell lines. The antibacterial activity screening results revealed that compounds, I(6) and I(12) have registered excellent inhibition against Escherichia coli and Bacillus subtilis in comparison with the standard drug Streptomycin. Compounds I(2) and I(11) have partially cleaved the DNA at 100 µg mL(-1) concentration.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Clivagem do DNA/efeitos dos fármacos , Indóis/farmacologia , Triazóis/farmacologia , Animais , Antibacterianos/administração & dosagem , Antibacterianos/síntese química , Antineoplásicos/administração & dosagem , Antineoplásicos/síntese química , Bacillus subtilis/efeitos dos fármacos , Ácidos Carboxílicos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Escherichia coli/efeitos dos fármacos , Células HEK293 , Células HeLa , Humanos , Indóis/administração & dosagem , Indóis/síntese química , Células MCF-7 , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Relação Estrutura-Atividade , Triazóis/administração & dosagem , Triazóis/síntese química
7.
Ecotoxicol Environ Saf ; 121: 16-21, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26242967

RESUMO

Renewable energy plays a predominant role in solving the current energy requirement problems and biodiesel is a promising alternative fuel to tide over the energy crisis and conserve fossil fuels. The present work investigates an eco-friendly substitute for the replacement of fossil fuels and the experiments are designed to determine the effects of a catalyst in the biodiesel production processes. Pongamia pinnata oil was utilized to produce the biodiesel by using catalysts namely KOH and NaOH and the properties of the fuel were found by using Carbon Hydrogen Nitrogen Sulfur (CHNS) elemental analysis, Fourier Transform Infrared (FTIR) Spectroscopy, Gas Chromatography & Mass Spectrometry (GC-MS), and Proton Nuclear Magnetic Resonance ((1)H NMR) Spectroscopy and the thermophysical properties were compared with those of neat diesel. In continuation, the working characteristics of the biodiesel and biodiesel-water emulsions were accomplished in a four stroke compression ignition engine and the results were compared to those of neat diesel. It was found that the exhaust emission characteristics like brake specific carbon monoxide (BSCO), brake specific hydrocarbons (BSHC) and smoke opacity were better for neat biodiesel (except brake specific nitric oxide BSNO) than those of neat diesel.


Assuntos
Biocombustíveis/análise , Pongamia/química , Carbono/química , Monóxido de Carbono/análise , Esterificação , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos/análise , Hidróxidos/química , Espectroscopia de Ressonância Magnética , Óxido Nítrico/análise , Óleos de Plantas/química , Compostos de Potássio/química , Fumaça/análise , Hidróxido de Sódio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Enxofre/química , Emissões de Veículos/análise
8.
J Insect Sci ; 142014.
Artigo em Inglês | MEDLINE | ID: mdl-25528748

RESUMO

Predicted increase in temperature and atmospheric CO2 concentration will influence the growth of crop plants and phytophagous insects. The present study, conducted at the Central Research Institute for Dryland Agriculture, Hyderabad, India, aimed at (1) construction of life tables at six constant temperatures viz., 20, 25, 27, 30, 33, and 35 ± 0.5 °C for Spodoptera litura (Fabricius) (Noctuidae: Lepidoptera) reared on sunflower (Helianthus annus L.) grown under ambient and elevated CO2 (eCO2) (550 ppm) concentration in open top chambers and (2) prediction of the pest status in near future (NF) and distant future (DF) climate change scenarios at major sunflower growing locations of India. Significantly lower leaf nitrogen, higher carbon and higher relative proportion of carbon to nitrogen (C:N) were observed in sunflower foliage grown under eCO2 over ambient. Feeding trials conducted on sunflower foliage obtained from two CO2 conditions showed that the developmental time of S. litura (Egg to adult) declined with increase in temperature and was more evident at eCO2. Finite (λ) and intrinsic rates of increase (r(m)), net reproductive rate (Ro), mean generation time, (T) and doubling time (DT) of S. litura increased significantly with temperature up to 27-30 °C and declined with further increase in temperature. Reduction of 'T' was observed from maximum value of 58 d at 20 °C to minimum of 24.9 d at 35 °C. The DT of population was higher (5.88 d) at 20 °C and lower (3.05 d) at 30 °C temperature of eCO2. The data on these life table parameters were plotted against temperature and two nonlinear models were developed separately for each of the CO2 conditions for predicting the pest scenarios. The NF and DF scenarios temperature data of four sunflower growing locations in India is based on PRECIS A1B emission scenario. It was predicted that increased 'rm', 'λ', and 'Ro' and reduced 'T' would occur during NF and DF scenario over present period at all locations. The present results indicate that temperature and CO2 are vital in influencing the population growth of S. litura and pest incidence may possibly be higher in the future.


Assuntos
Dióxido de Carbono/farmacologia , Mudança Climática , Helianthus/efeitos dos fármacos , Spodoptera/efeitos dos fármacos , Spodoptera/crescimento & desenvolvimento , Animais , Helianthus/química , Índia , Estágios do Ciclo de Vida/efeitos dos fármacos , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Spodoptera/fisiologia , Temperatura
9.
Indian Heart J ; 66(5): 525-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25443606

RESUMO

BACKGROUND: Second generation bare metal stents made of cobalt chromium alloy are superior to first generation stain less steel stents. The thin struts are shown to reduce clinical and angiographic adverse outcomes. OBJECTIVE: To study the long term clinical and angiographic outcomes in patients who underwent coronary angioplasty with an indigenously made cobalt chromium bare metal stents with thin strut Cobal+C™ (Relisys). METHODS: A total of 268 consecutive patients who underwent coronary angioplasty with Cobal+C stents were studied retrospectively. Clinical follow up was done after a minimum period of nine months through telephonic interview and angiographic follow up was done in 80 patients chosen randomly. The end points analyzed included major adverse cardiac events (MACE) at nine months and the rate of binary restenosis at follow up angiogram done between 9 and 15 months post angioplasty. RESULTS: Thirty four percent were diabetic and 33% had acute myocardial infarction. Females constituted 17%. Mean stent diameter was 2.88 ± 0.28 and mean stent length 18.8 ± 4.2. MACE at nine months was 4.5% with TLR 0.3%. The rate of binary restenosis was 21%. Patients with longer stent lengths and non-compliance with medications had significantly higher rates of binary restenosis. CONCLUSIONS: The use of Relisys Cobal+C stents was associated with good long term clinical and angiographic outcomes as evidenced by low incidence of MACE and binary restenosis rates for a bare metal stent.


Assuntos
Doença das Coronárias/cirurgia , Desenho de Prótese , Stents , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia Coronária com Balão , Cromo , Cobalto , Angiografia Coronária , Reestenose Coronária/epidemiologia , Feminino , Seguimentos , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea , Estudos Retrospectivos , Resultado do Tratamento
10.
Epidemiol Infect ; 142(10): 2227-36, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24398247

RESUMO

Monitoring of malaria intensity in terrain regions of Arunachal Pradesh, India is very difficult as the dynamics of mosquito populations varies to a large extent due to altitude and frequent changes in climatic conditions. There is a scarcity of information on the influence of climatic factors on malaria morbidity in Arunachal Pradesh. Hence, a pilot study was conducted from 2006 to 2010 to understand malaria transmission dynamics, seasonal distribution and disease morbidity. Plasmodium vivax and P. falciparum are the two major parasites for malaria transmission in Arunachal Pradesh. Out of 142 558 malaria cases analysed from 2006 to 2010, P. vivax infection contributed 72·1% followed by P. falciparum (27·9%). However, the overall morbidity of malaria declined from 37/1000 in 2006 to 18/1000 population in 2010. From this study it was observed that the temporal distribution of malaria cases varied between districts and high morbidity rates were reported mostly during the wet season. To understand malaria transmission dynamics in the study area, the Richards model was used to predict malaria cases. The output of the results from this model predicted a higher number of malaria cases (K) during 2006 and a gradual decline in subsequent years. Similarly, the growth rate r, and exponential deviation α, were almost identical for all the years, which shows that the Richards model is the most suitable model for the prediction of malaria cases.


Assuntos
Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Estações do Ano , Animais , Humanos , Incidência , Índia/epidemiologia , Malária/epidemiologia , Malária/transmissão , Malária Falciparum/transmissão , Malária Vivax/transmissão , Modelos Estatísticos , Projetos Piloto , Prevalência
11.
Bioorg Med Chem Lett ; 22(17): 5639-47, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22871579

RESUMO

Novel polysubstituted pyrroles have been designed and accessed via a one-pot multicomponent reaction followed by Pd-mediated C-C bond forming reactions. All the compounds synthesized were tested for their PDE4B inhibitory properties in vitro and two of them obtained via Heck reaction showed significant inhibition. The docking results suggested that these alkenyl derivatives containing ester moiety interact well with the PDE4B protein in silico where the ester carbonyl oxygen played a key role. The pyrrole framework presented here could be a new template for the identification of small molecule based novel inhibitors of PDE4. The single crystal X-ray data of a representative compound is presented.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Inibidores da Fosfodiesterase 4/química , Inibidores da Fosfodiesterase 4/farmacologia , Pirróis/química , Pirróis/farmacologia , Animais , Catálise , Linhagem Celular , Cristalografia por Raios X , Modelos Moleculares , Paládio/química , Relação Estrutura-Atividade
12.
J Insect Sci ; 12: 103, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23437971

RESUMO

If the carbon dioxide (CO(2)) concentration in the atmosphere changes in the future, as predicted, it could influence crops and insect pests. The growth and development of the tobacco caterpillar, Spodoptera litura (Fabricius) (Noctuidae: Lepidoptera), reared on peanut (Arachis hypogea L.) foliage grown under elevated CO(2) (550 ppm and 700 ppm) concentrations in open top chambers at Central Research Institute for Dryland Agriculture, Hyderabad, India, were examined in this study. Significantly lower leaf nitrogen, higher carbon, higher relative proportion of carbon to nitrogen and higher polyphenols content expressed in terms of tannic acid equivalents were observed in the peanut foliage grown under elevated CO(2) levels. Substantial influence of elevated CO(2) on S. litura was noticed, such as longer larval duration, higher larval weights, and increased consumption of peanut foliage by S. litura larvae under elevated CO(2) compared with ambient CO(2). Relative consumption rate was significantly higher for S. litura larva fed plants grown at 550 and 700 ppm than for larvae fed plants grown at ambient condition. Decreased efficiency of conversion of ingested food, decreased efficiency of conversion of digested food, and decreased relative growth rate of larvae was observed under elevated CO(2). The present results indicate that elevated CO(2) levels altered the quality of the peanut foliage, resulting in higher consumption, lower digestive efficiency, slower growth, and longer time to pupation (one day more than ambient).


Assuntos
Arachis/crescimento & desenvolvimento , Dióxido de Carbono/farmacologia , Herbivoria , Spodoptera/fisiologia , Análise de Variância , Animais , Arachis/efeitos dos fármacos , Índia , Controle de Insetos , Larva/fisiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Espectrofotometria , Spodoptera/efeitos dos fármacos
13.
Bioorg Med Chem Lett ; 21(21): 6510-4, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21924612

RESUMO

Indole and its derivatives undergo smooth conjugate addition onto en-1,4-dione derived from isatin and acetophenone, in the presence of a catalytic amount of molecular iodine in acetonitrile under mild conditions to afford a novel class of 3-(1-(1H-indol-3-yl)-2-oxo-2-phenylethyl)indolin-2-one derivatives in good yields with high degree of 1,4-selectivity. Some of these compounds are found to exhibit modest antibacterial and antifungal properties.


Assuntos
Antibacterianos/química , Antifúngicos/química , Indóis/química , Iodo/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Catálise , Iodo/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Espectrofotometria Infravermelho
14.
Bioorg Med Chem Lett ; 21(13): 3890-3, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21641208

RESUMO

A simple and efficient synthetic approach toward a series of chiral aryl boronate esters, starting from D-xylose, as anti-microbial agents, is described herein. Minimum inhibitory concentration and zone of inhibition revealed that these derivatives exhibit potent anti-bacterial and anti-fungal properties. Herein, we report the first anti-microbial activity of this class of compounds. All products have been characterized by NMR ((1)H, (13)C and (11)B), IR, elemental and mass spectral study.


Assuntos
Antibacterianos , Antifúngicos , Bactérias/efeitos dos fármacos , Ésteres/síntese química , Ésteres/farmacologia , Fungos/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Boratos/síntese química , Boratos/química , Boratos/farmacologia , Ésteres/química , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Xilose/síntese química , Xilose/química , Xilose/farmacologia
15.
Pharmazie ; 65(5): 336-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20503924

RESUMO

Rivastigmine is a drug against Alzheimer's disease, and is a non-pharmacopoeial compound. During the preparation of rivastigmine in our laboratory, two impurities were detected and identified with a simple and sensitive reversed-phase liquid chromatography coupled with electrospray-mass spectrometry. The same impurities were also observed in commercial batches. These impurities were isolated by preparative HPLC and co-injected with rivastigmine sample to confirm the retention times in HPLC. These impurities were characterized as N,N-dimethyl-3-[1-dimethylaminoethyl]phenylcarboxylate (dimethyl-rivastigmine) and N,N-diethyl-3-[1-dimethylaminoethyl]phenylcarboxamide (diethyl-rivastigmine). Structural elucidation of these impurities by spectral data (1H NMR, 13C NMR and MS) is discussed.


Assuntos
Inibidores da Colinesterase/análise , Contaminação de Medicamentos , Fenilcarbamatos/análise , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Rivastigmina , Espectrometria de Massas por Ionização por Electrospray
16.
Pharmazie ; 63(1): 14-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18271296

RESUMO

In the process for the preparation of quetiapine fumarate (1), six unknown impurities and one known impurity (intermediate) were identified ranging from 0.05-0.15% by reverse-phase HPLC. These impurities were isolated from crude samples using reverse-phase preparative HPLC. Based on the spectral data, the impurities were characterized as 2-[4-dibenzo[b,f][1,4]thiazepine-11-yl-1 -piperazinyl]1 -2-ethanol (impurity I, desethanol quetiapine), 11-[(N-formyl)-1-piperazinyl]-dibenzo[b,f][1,4]thiazepine (impurity II, N-formyl piperazinyl thiazepine), 2-(2-hydroxy ethoxy)ethyl-2-[2-[4-dibenzo[b,f][1,4]thiazepine-11- piperazinyl-1-carboxylate (impurity III, quetiapine carboxylate), 11-[4-ethyl-1-piperazinyl]dibenzo [b,f][1,4] thiazepine (impurity IV, ethylpiperazinyl thiazepine), 2-[2-(4-dibenzo[b,f][1,4]thiazepin-11-yl-1-piperazinyl)ethoxy]1-ethyl ethanol [impurity V, ethyl quetiapine), 1,4-bis[dibenzo[b,f][1,4]thiazepine-11-yl] piperazine [impurity VI, bis(dibenzo)piperazine]. The known impurity was an intermediate, 11-piperazinyldibenzo [b,f][1,4]thiazepine (piperazinyl thiazepine). The structures were established unambiguously by independent synthesis and co-injection in HPLC to confirm the retention times. To the best of our knowledge, these impurities have not been reported before. Structural elucidation of all impurities by spectral data (1H NMR, 13C NMR, MS and IR), synthesis and formation of these impurities are discussed in detail.


Assuntos
Dibenzotiazepinas/química , Cromatografia Líquida de Alta Pressão , Contaminação de Medicamentos , Espectroscopia de Ressonância Magnética , Fumarato de Quetiapina , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Pediatr Surg Int ; 20(6): 467-8, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15095104

RESUMO

Oesophageal atresia is known to be associated with cardiovascular, gastrointestinal, genitourinary and skeletal anomalies. Its association with biliary atresia is very rare and only a few cases have been reported in the literature. Although biliary atresia could be part of a multiple anomaly syndrome, its isolated occurrence is even rare. We present a case of oesophageal atresia associated with biliary atresia.


Assuntos
Atresia Biliar/complicações , Atresia Esofágica/complicações , Anormalidades Múltiplas/epidemiologia , Humanos , Recém-Nascido , Masculino
18.
Phytochemistry ; 61(8): 931-6, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12453520

RESUMO

Crotaoprostrin, a chalcone not yet known as a plant constituent, was isolated from the aerial parts of the Indian medicinal plant Crotalaria prostrata. The structures of the chalcone polyarvin and the partially hydrogenated naturally occurring derivatives crotaramin, crotaramosmin, and crotin were confirmed by chemical synthesis.


Assuntos
Chalcona/análogos & derivados , Chalcona/isolamento & purificação , Chalcona/síntese química , Fabaceae/química , Estrutura Molecular , Componentes Aéreos da Planta/química
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