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Pesquisa : D02.455.426.559 [Categoria DeCS]
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[PMID]:29394011
[Au] Autor:Saladino R; Chiocchini U; Botta G; Delfino M; Conigliaro R; Mosesso P
[Ti] Título:Free radical scavenging capacity and protective effect of natural substances in peloids from the thermal spring pool Bagnaccio (Viterbo, Italy).
[So] Source:J Cosmet Sci;67(2):71-92, 2016 Mar-Apr.
[Is] ISSN:1525-7886
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Natural peloids from sulfurous thermal springs are largely used in cosmetic and pelotherapy for the treatment of different dermatological conditions, including skin aging, dermatitis, and other eczemas. The beneficial effects are correlated to mineralogical and other thermal properties, as well as to the presence of natural substances with specific antioxidant activity. Few data are available for the comparison between natural peloids and synthetic (i.e., artificially maturated) muds. In this context, the natural substances and antioxidant activity of natural white mud (WM) and dark mud (DM) peloids from the sulfurous thermal spring pool Bagnaccio (Viterbo, Italy) have been studied in detail to evaluate possible relationships between physicochemical properties and therapeutic effect. A large panel of natural substances in WM and DM were characterized for the first time by ³¹P-nuclear magnetic resonance and gas chromatography associated to mass spectrometry analysis. Polar fractions of WM and DM peloids were characterized by the presence of several bioactive natural compounds, showing high antioxidant activity and DNA protective effect, as evaluated by 2,2-diphenyl-1-picrylhydrazyl assay, and hydrogen peroxide­induced DNA breakage in the alkaline comet assay. The antioxidant activity and DNA protective effect could be attributed to radical scavenging rather than a modulatory effect on the induced DNA repair, and are of order of intensity higher than that reported for synthetic muds.
[Mh] Termos MeSH primário: Alcaloides/farmacologia
Depuradores de Radicais Livres/farmacologia
Hidrocarbonetos Aromáticos/farmacologia
Fenóis/farmacologia
Terpenos/farmacologia
[Mh] Termos MeSH secundário: Alcaloides/química
Alcaloides/isolamento & purificação
Alcanos/química
Alcanos/isolamento & purificação
Alcanos/farmacologia
Alcenos/química
Alcenos/isolamento & purificação
Alcenos/farmacologia
Animais
Compostos de Bifenilo/antagonistas & inibidores
Compostos de Bifenilo/química
Células CHO
Linhagem Celular Tumoral
Sobrevivência Celular/efeitos dos fármacos
Ensaio Cometa
Cricetulus
DNA/efeitos dos fármacos
Depuradores de Radicais Livres/química
Depuradores de Radicais Livres/isolamento & purificação
Fontes Termais
Seres Humanos
Hidrocarbonetos Aromáticos/química
Hidrocarbonetos Aromáticos/isolamento & purificação
Peróxido de Hidrogênio/antagonistas & inibidores
Peróxido de Hidrogênio/química
Itália
Espectroscopia de Ressonância Magnética
Camundongos
Terapia por Lama
Fenóis/química
Fenóis/isolamento & purificação
Picratos/antagonistas & inibidores
Picratos/química
Terpenos/química
Terpenos/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alkaloids); 0 (Alkanes); 0 (Alkenes); 0 (Biphenyl Compounds); 0 (Free Radical Scavengers); 0 (Hydrocarbons, Aromatic); 0 (Phenols); 0 (Picrates); 0 (Terpenes); 9007-49-2 (DNA); BBX060AN9V (Hydrogen Peroxide); DFD3H4VGDH (1,1-diphenyl-2-picrylhydrazyl)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180203
[St] Status:MEDLINE


  2 / 2915 MEDLINE  
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[PMID]:28917820
[Au] Autor:Ma P; Zhang P; Shu J; Yang B; Zhang H
[Ad] Endereço:State Key Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
[Ti] Título:Characterization of secondary organic aerosol from photo-oxidation of gasoline exhaust and specific sources of major components.
[So] Source:Environ Pollut;232:65-72, 2018 Jan.
[Is] ISSN:1873-6424
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:To further explore the composition and distribution of secondary organic aerosol (SOA) components from the photo-oxidation of light aromatic precursors (toluene, m-xylene, and 1,3,5-trimethylbenzene (1,3,5-TMB)) and idling gasoline exhaust, a vacuum ultraviolet photoionization mass spectrometer (VUV-PIMS) was employed. Peaks of the molecular ions of the SOA components with minimum molecular fragmentation were clearly observed from the mass spectra of SOA, through the application of soft ionization methods in VUV-PIMS. The experiments comparing the exhaust-SOA and light aromatic mixture-SOA showed that the observed distributions of almost all the predominant cluster ions in the exhaust-SOA were similar to that of the mixture-SOA. Based on the characterization experiments of SOA formed from individual light aromatic precursors, the SOA components with molecular weights of 98 and 110 amu observed in the exhaust-SOA resulted from the photo-oxidation of toluene and m-xylene; the components with a molecular weight of 124 amu were derived mainly from m-xylene; and the components with molecular weights of 100, 112, 128, 138, and 156 amu were mainly derived from 1,3,5-TMB. These results suggest that C -C light aromatic hydrocarbons are significant SOA precursors and that major SOA components originate from gasoline exhaust. Additionally, some new light aromatic hydrocarbon-SOA components were observed for the first time using VUV-PIMS. The corresponding reaction mechanisms were also proposed in this study to enrich the knowledge base of the formation mechanisms of light aromatic hydrocarbon-SOA compounds.
[Mh] Termos MeSH primário: Aerossóis/análise
Gasolina/análise
Processos Fotoquímicos
Emissões de Veículos/análise
[Mh] Termos MeSH secundário: Hidrocarbonetos Aromáticos
Espectrometria de Massas
Peso Molecular
Oxirredução
Tolueno
Xilenos/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Aerosols); 0 (Gasoline); 0 (Hydrocarbons, Aromatic); 0 (Vehicle Emissions); 0 (Xylenes); 3FPU23BG52 (Toluene); O9XS864HTE (3-xylene)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180208
[Lr] Data última revisão:
180208
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170918
[St] Status:MEDLINE


  3 / 2915 MEDLINE  
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[PMID]:28779665
[Au] Autor:Zheng N; Zhang J; Wang J
[Ad] Endereço:Department of Chemical Engineering for Energy, Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education, East China University of Science and Technology, 130 # Meilong Rd, Shanghai 200237, PR China.
[Ti] Título:Parametric study of two-stage hydropyrolysis of lignocellulosic biomass for production of gaseous and light aromatic hydrocarbons.
[So] Source:Bioresour Technol;244(Pt 1):142-150, 2017 Nov.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Non-catalytic hydropyrolysis of pinewood and its components was carried out using a two-stage reactor. The main aim of this work is to investigate the hydrodeoxygenation and hydrogenation of volatile matter in the post hydrocracking reactor for oriented production of gaseous and light aromatic hydrocarbons. A portion of volatile matter, which evolved from hemicellulose, neutral extractives and lignin below 275°C, was found to be thoroughly hydrodeoxygenated preventing the release of CO and CO. Increasing hydrocracking temperature from 600°C to 750°C and pressure from 1.0MPa to 5.0MPa strongly facilitated the hydrogenation reactions to target products. The summed yield of CH and C H (dry biomass basis) reached up to 33.2% at a hydrocracking temperature of 750°C and 5.0MPa, with a concomitant 5.1% yield of BTX. All components in pinewood significantly contributed to the production of CH and BTX by hydropyrolysis, differing from the case of pyrolysis.
[Mh] Termos MeSH primário: Hidrocarbonetos Aromáticos
[Mh] Termos MeSH secundário: Biomassa
Gases
Lignina
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Gases); 0 (Hydrocarbons, Aromatic); 9005-53-2 (Lignin)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171103
[Lr] Data última revisão:
171103
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170806
[St] Status:MEDLINE


  4 / 2915 MEDLINE  
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[PMID]:28754364
[Au] Autor:Yamauchi S; Wukirsari T; Ochi Y; Nishiwaki H; Nishi K; Sugahara T; Akiyama K; Kishida T
[Ad] Endereço:Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan; South Ehime Fisheries Research Center, 1289-1 Funakoshi, Ainan, Ehime 798-4292, Japan. Electronic address: syamauch@agr.ehime-u.ac.jp.
[Ti] Título:Syntheses of cytotoxic novel arctigenin derivatives bearing halogen and alkyl groups on aromatic rings.
[So] Source:Bioorg Med Chem Lett;27(17):4199-4203, 2017 09 01.
[Is] ISSN:1464-3405
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The new lignano-9,9'-lactones (α,ß-dibenzyl-γ-butyrolactone lignans), which showed the higher cytotoxicity than arctigenin, were synthesized. The well-known cytotoxic arctigenin showed activity against HL-60 cells (EC =12µM), however, it was inactive against HeLa cells (EC >100µM). The synthesized (3,4-dichloro, 2'-butoxy)-derivative 55 and (3,4-dichloro, 4'-butyl)-derivative 66 bearing the lignano-9,9'-lactone structures showed the EC values of 10µM and 9.4µM against HL-60 cells, respectively. Against HeLa cells, the EC value of the derivative 66 was 27µM. By comparing the activities with the corresponding 9,9'-epoxy structure (tetrahydrofuran compounds), the importance of the lactone structure of 55 and 66 for the higher activities was shown. The substituents on the aromatic ring of the lignano-9,9'-lactones affected the cytotoxicity level, observing more than 10-fold difference.
[Mh] Termos MeSH primário: Antineoplásicos/farmacologia
Furanos/farmacologia
Halogênios/farmacologia
Hidrocarbonetos Aromáticos/farmacologia
Lignanas/farmacologia
[Mh] Termos MeSH secundário: Antineoplásicos/síntese química
Antineoplásicos/química
Proliferação Celular/efeitos dos fármacos
Relação Dose-Resposta a Droga
Ensaios de Seleção de Medicamentos Antitumorais
Furanos/síntese química
Furanos/química
Células HL-60
Halogênios/química
Células HeLa
Seres Humanos
Hidrocarbonetos Aromáticos/química
Lignanas/síntese química
Lignanas/química
Conformação Molecular
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Antineoplastic Agents); 0 (Furans); 0 (Halogens); 0 (Hydrocarbons, Aromatic); 0 (Lignans); U76MR9VS6M (arctigenin)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171125
[Lr] Data última revisão:
171125
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170730
[St] Status:MEDLINE


  5 / 2915 MEDLINE  
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[PMID]:28650569
[Au] Autor:Sahoo B; Formenti D; Topf C; Bachmann S; Scalone M; Junge K; Beller M
[Ad] Endereço:Leibniz-Institut für Katalyse e.V. an der, Universität Rostock, Albert-Einstein-Straße 29a, 18059, Rostock, Germany.
[Ti] Título:Biomass-Derived Catalysts for Selective Hydrogenation of Nitroarenes.
[So] Source:ChemSusChem;10(15):3035-3039, 2017 Aug 10.
[Is] ISSN:1864-564X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Development of catalytically active materials from biowaste represents an important aspect of sustainable chemical research. Three heterogeneous materials were synthesized from inexpensive biomass-based chitosan and abundant Co(OAc) using complexation followed by pyrolysis at various temperatures. These materials were applied in the catalytic hydrogenation of nitroarenes using molecular hydrogen. A variety of diversely functionalized nitroarenes including some pharmaceutically active compounds were converted into aromatic amines in high yields, with high selectivity, and with excellent functional group tolerance. This green protocol has also been implemented for the synthesis of a biologically important TRPC3 inhibitor.
[Mh] Termos MeSH primário: Biomassa
Hidrocarbonetos Aromáticos/química
Nitrocompostos/química
[Mh] Termos MeSH secundário: Catálise
Hidrogenação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hydrocarbons, Aromatic); 0 (Nitro Compounds)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170829
[Lr] Data última revisão:
170829
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170627
[St] Status:MEDLINE
[do] DOI:10.1002/cssc.201700796


  6 / 2915 MEDLINE  
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[PMID]:28650097
[Au] Autor:Rakstys K; Paek S; Grancini G; Gao P; Jankauskas V; Asiri AM; Nazeeruddin MK
[Ad] Endereço:Group for Molecular Engineering of Functional Materials, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne, 1951, Sion, Switzerland.
[Ti] Título:Low-Cost Perovskite Solar Cells Employing Dimethoxydiphenylamine-Substituted Bistricyclic Aromatic Enes as Hole Transport Materials.
[So] Source:ChemSusChem;10(19):3825-3832, 2017 Oct 09.
[Is] ISSN:1864-564X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:The synthesis, characterization and photovoltaic performance of series of novel molecular hole transport materials (HTMs) based on bistricyclic aromatic enes (BAEs) are presented. The new derivatives were obtained following a simple and straightforward procedure from inexpensive starting reagents mimicking the synthetically challenging 9,9'-spirobifluorene moiety of the well-studied spiro-OMeTAD. The novel HTMs were tested in mixed cations and anions perovskite solar cells (PSCs) yielding a power conversion efficiency (PCE) of 19.2 % under standard global 100 mW cm AM1.5G illumination using 9-{2,7-bis[bis(4-methoxyphenyl)amino]-9H-fluoren-9-ylidene}-N ,N ,N ,N -tetrakis(4-methoxyphenyl)-9H-thioxanthene-2,7-diamine (coded as KR374). The power conversion efficiency data confirms the easily attainable heteromerous fluorenylidenethioxanthene structure as valuable core for low-cost and highly efficient HTM design and paves the way towards cost-effective PSC technology.
[Mh] Termos MeSH primário: Aminas/química
Compostos de Cálcio/química
Custos e Análise de Custo
Fontes de Energia Elétrica/economia
Hidrocarbonetos Aromáticos/química
Óxidos/química
Energia Solar
Titânio/química
[Mh] Termos MeSH secundário: Eletroquímica
Modelos Moleculares
Conformação Molecular
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amines); 0 (Calcium Compounds); 0 (Hydrocarbons, Aromatic); 0 (Oxides); 12194-71-7 (perovskite); D1JT611TNE (Titanium)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171106
[Lr] Data última revisão:
171106
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170627
[St] Status:MEDLINE
[do] DOI:10.1002/cssc.201700974


  7 / 2915 MEDLINE  
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[PMID]:28624700
[Au] Autor:Wang L; Bao BB; Song GQ; Chen C; Zhang XM; Lu W; Wang Z; Cai Y; Li S; Fu S; Song FH; Yang H; Wang JG
[Ad] Endereço:State-Key Laboratory and Research Institute of Elemento-Organic Chemistry, National Pesticide Engineering Research Center, College of Chemistry, Nankai University, Tianjin 300071, China.
[Ti] Título:Discovery of unsymmetrical aromatic disulfides as novel inhibitors of SARS-CoV main protease: Chemical synthesis, biological evaluation, molecular docking and 3D-QSAR study.
[So] Source:Eur J Med Chem;137:450-461, 2017 Sep 08.
[Is] ISSN:1768-3254
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:The worldwide outbreak of severe acute respiratory syndrome (SARS) in 2003 had caused a high rate of mortality. Main protease (M ) of SARS-associated coronavirus (SARS-CoV) is an important target to discover pharmaceutical compounds for the therapy of this life-threatening disease. During the course of screening new anti-SARS agents, we have identified that a series of unsymmetrical aromatic disulfides inhibited SARS-CoV M significantly for the first time. Herein, 40 novel unsymmetrical aromatic disulfides were synthesized chemically and their biological activities were evaluated in vitro against SARS-CoV M . These novel compounds displayed excellent IC data in the range of 0.516-5.954 µM. Preliminary studies indicated that these disulfides are reversible and mpetitive inhibitors. A possible binding mode was generated via molecular docking simulation and a comparative field analysis (CoMFA) model was constructed to understand the structure-activity relationships. The present research therefore has provided some meaningful guidance to design and identify anti-SARS drugs with totally new chemical structures.
[Mh] Termos MeSH primário: Antivirais/farmacologia
Dissulfetos/farmacologia
Descoberta de Drogas
Hidrocarbonetos Aromáticos/farmacologia
Simulação de Acoplamento Molecular
Inibidores de Proteases/farmacologia
Relação Quantitativa Estrutura-Atividade
Vírus da SARS/efeitos dos fármacos
Proteínas Virais/antagonistas & inibidores
[Mh] Termos MeSH secundário: Antivirais/síntese química
Antivirais/química
Cisteína Endopeptidases/metabolismo
Dissulfetos/síntese química
Dissulfetos/química
Relação Dose-Resposta a Droga
Hidrocarbonetos Aromáticos/síntese química
Hidrocarbonetos Aromáticos/química
Testes de Sensibilidade Microbiana
Estrutura Molecular
Inibidores de Proteases/síntese química
Inibidores de Proteases/química
Vírus da SARS/enzimologia
Proteínas Virais/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antiviral Agents); 0 (Disulfides); 0 (Hydrocarbons, Aromatic); 0 (Protease Inhibitors); 0 (Viral Proteins); EC 3.4.22.- (3C-like protease, SARS coronavirus); EC 3.4.22.- (Cysteine Endopeptidases)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170920
[Lr] Data última revisão:
170920
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170619
[St] Status:MEDLINE


  8 / 2915 MEDLINE  
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[PMID]:28558334
[Au] Autor:Zhao S; Zhang X; Wei P; Su X; Zhao L; Wu M; Hao C; Liu C; Zhao D; Cheng M
[Ad] Endereço:Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, PR China.
[Ti] Título:Design, synthesis and evaluation of aromatic heterocyclic derivatives as potent antifungal agents.
[So] Source:Eur J Med Chem;137:96-107, 2017 Sep 08.
[Is] ISSN:1768-3254
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:To further enhance the anti-Aspergillus efficacy of our previously discovered antifungal lead compounds (1), a series of aromatic heterocyclic derivatives were designed, synthesized and evaluated for in vitro antifungal activity. Many of the target compounds showed good inhibitory activity against Candida albicans and Cryptococcus neoformans. In particular, the isoxazole nuclei were more suited for improving the activity against Aspergillus spp. Among these compounds, 2-F substituted analogues 23g and 23h displayed the most remarkable in vitro activity against Candida spp., C. neoformans, A. fumigatus and fluconazole-resistant C.alb. strains, which is superior or comparable to the activity of the reference drugs fluconazole and voriconazole. Notably, the compounds 23g and 23h exhibited low inhibition profiles for various isoforms of human cytochrome P450 and excellent blood plasma stability.
[Mh] Termos MeSH primário: Antifúngicos/farmacologia
Aspergillus fumigatus/efeitos dos fármacos
Candida albicans/efeitos dos fármacos
Cryptococcus neoformans/efeitos dos fármacos
Compostos Heterocíclicos/farmacologia
Hidrocarbonetos Aromáticos/farmacologia
[Mh] Termos MeSH secundário: Antifúngicos/síntese química
Antifúngicos/química
Relação Dose-Resposta a Droga
Desenho de Drogas
Compostos Heterocíclicos/síntese química
Compostos Heterocíclicos/química
Hidrocarbonetos Aromáticos/síntese química
Hidrocarbonetos Aromáticos/química
Testes de Sensibilidade Microbiana
Estrutura Molecular
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antifungal Agents); 0 (Heterocyclic Compounds); 0 (Hydrocarbons, Aromatic)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170920
[Lr] Data última revisão:
170920
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170531
[St] Status:MEDLINE


  9 / 2915 MEDLINE  
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[PMID]:28533029
[Au] Autor:Nestola M; Schmidt TC
[Ad] Endereço:Axel Semrau GmbH & Co. KG, Stefansbecke 42, D-45549 Sprockhövel, Germany. Electronic address: Nestola@axelsemrau.de.
[Ti] Título:Determination of mineral oil aromatic hydrocarbons in edible oils and fats by online liquid chromatography-gas chromatography-flame ionization detection - Evaluation of automated removal strategies for biogenic olefins.
[So] Source:J Chromatogr A;1505:69-76, 2017 Jul 07.
[Is] ISSN:1873-3778
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The determination of mineral oil aromatic hydrocarbons (MOAH) in foodstuffs gained in importance over the last years as carcinogenicity cannot be excluded for certain MOAH. The existence of olefins in foodstuffs, such as edible oils and fats, can be problematic for the determination of MOAH by LC-GC-FID. Removal of these interfering substances by HPLC based on polarity differences is not possible. During gas chromatographic separation heavily overloaded peaks are observed rendering the detection of small mineral oil contaminations almost impossible. Therefore, removal of these olefins is necessary before subjection of the sample to LC-GC-FID. Epoxidation of olefins to increase their polarity proved to be a valuable tool in the past. Precision and trueness of the results as shown in a collaborative trial, however, are relying on exact reaction conditions. Additionally, it is known that certain MOAH are oxidized during epoxidation and therefore get lost. In the scope of this work, hydroboration, bromohydrin reaction, and epoxidation were examined for their potential for derivatization of unsaturated hydrocarbons with increased robustness and higher recovery of MOAH. Epoxidation by meta-chloroperoxybenzoic acid (mCPBA) delivered the best removal of olefins. Factors influencing this reaction were enlightened. Adaption of the reaction conditions and time-controlled automation increased the recovery of polycyclic MOAH. Good precision (RSD <1.5%) and recovery (95-102%) for MOAH were also observed for sunflower and olive oils spiked with a lubricating mineral oil (at 24.5mg/kg of MOAH). The trueness of the method was verified by analyzing collaborative trial samples.
[Mh] Termos MeSH primário: Alcenos/análise
Cromatografia Gasosa/métodos
Cromatografia Líquida de Alta Pressão/métodos
Gorduras/química
Contaminação de Alimentos/análise
Hidrocarbonetos Aromáticos/análise
Óleo Mineral/análise
Óleos Vegetais/química
[Mh] Termos MeSH secundário: Alcenos/isolamento & purificação
Cromatografia Gasosa/instrumentação
Cromatografia Líquida de Alta Pressão/instrumentação
Ionização de Chama
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alkenes); 0 (Fats); 0 (Hydrocarbons, Aromatic); 0 (Plant Oils); 8020-83-5 (Mineral Oil)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170524
[St] Status:MEDLINE


  10 / 2915 MEDLINE  
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[PMID]:28485585
[Au] Autor:Sellers BD; James NC; Gobbi A
[Ad] Endereço:Department of Discovery Chemistry, Genentech, Inc. , 1 DNA Way, South San Francisco, California 94080, United States.
[Ti] Título:A Comparison of Quantum and Molecular Mechanical Methods to Estimate Strain Energy in Druglike Fragments.
[So] Source:J Chem Inf Model;57(6):1265-1275, 2017 Jun 26.
[Is] ISSN:1549-960X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Reducing internal strain energy in small molecules is critical for designing potent drugs. Quantum mechanical (QM) and molecular mechanical (MM) methods are often used to estimate these energies. In an effort to determine which methods offer an optimal balance in accuracy and performance, we have carried out torsion scan analyses on 62 fragments. We compared nine QM and four MM methods to reference energies calculated at a higher level of theory: CCSD(T)/CBS single point energies (coupled cluster with single, double, and perturbative triple excitations at the complete basis set limit) calculated on optimized geometries using MP2/6-311+G**. The results show that both the more recent MP2.X perturbation method as well as MP2/CBS perform quite well. In addition, combining a Hartree-Fock geometry optimization with a MP2/CBS single point energy calculation offers a fast and accurate compromise when dispersion is not a key energy component. Among MM methods, the OPLS3 force field accurately reproduces CCSD(T)/CBS torsion energies on more test cases than the MMFF94s or Amber12:EHT force fields, which struggle with aryl-amide and aryl-aryl torsions. Using experimental conformations from the Cambridge Structural Database, we highlight three example structures for which OPLS3 significantly overestimates the strain. The energies and conformations presented should enable scientists to estimate the expected error for the methods described and we hope will spur further research into QM and MM methods.
[Mh] Termos MeSH primário: Fenômenos Mecânicos
Preparações Farmacêuticas/química
Teoria Quântica
[Mh] Termos MeSH secundário: Acetamidas/química
Hidrocarbonetos Aromáticos/química
Modelos Moleculares
Conformação Molecular
Estresse Mecânico
Tiazóis/química
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetamides); 0 (Hydrocarbons, Aromatic); 0 (Pharmaceutical Preparations); 0 (Thiazoles); 8XOE1JSO29 (acetamide)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170921
[Lr] Data última revisão:
170921
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170510
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jcim.6b00614



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