Base de dados : MEDLINE
Pesquisa : D02.113 [Categoria DeCS]
Referências encontradas : 1782 [refinar]
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  1 / 1782 MEDLINE  
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[PMID]:28674327
[Au] Autor:Trabelsi I; Essid K; Frikha MH
[Ad] Endereço:Laboratory of Physical and Organic Chemistry: Department of Chemistry, Faculty of Sciences in Sfax.
[Ti] Título:Esterification of Mixed Carboxylic-fatty Anhydrides Using Amberlyst-15 as Heterogeneous Catalyst.
[So] Source:J Oleo Sci;66(7):667-676, 2017.
[Is] ISSN:1347-3352
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:The article deals with the use of mixed anhydrides for the synthesis of fatty esters. Both aliphatic and aromatic acids are involved, indicating different behaviors according to the chain length of the aliphatic acid. We describe a novel and efficient method for the synthesis of fatty esters by the esterification reaction of primary, secondary and tertiary alcohols with mixed carboxylic-palmitic anhydrides using resin Amberlyst-15 as heterogeneous acid catalyst. Influence of various reaction parameters such as molar ratio (anhydride/alcohol), catalyst amount, type of alcohol and type of mixed anhydride were studied to optimize the conditions for maximum yield. Among tested anhydrides we quote mainly the 4-chlorobenzoic palmitic anhydride because it was both reactive and selective for the preparation of palmitic acid ester. This anhydride gave a good yield of palmitic ester.
[Mh] Termos MeSH primário: Anidridos/química
Ésteres/síntese química
Ácidos Graxos/química
Estirenos/química
[Mh] Termos MeSH secundário: Ácidos Carboxílicos/química
Catálise
Clorobenzoatos/química
Esterificação
Ácido Palmítico/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anhydrides); 0 (Carboxylic Acids); 0 (Chlorobenzoates); 0 (Esters); 0 (Fatty Acids); 0 (Styrenes); 0 (amberlyst-15); 2V16EO95H1 (Palmitic Acid); IC7888DF4L (4-chlorobenzoic acid)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171009
[Lr] Data última revisão:
171009
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170705
[St] Status:MEDLINE
[do] DOI:10.5650/jos.ess17008


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[PMID]:28380375
[Au] Autor:Wagner GR; Bhatt DP; O'Connell TM; Thompson JW; Dubois LG; Backos DS; Yang H; Mitchell GA; Ilkayeva OR; Stevens RD; Grimsrud PA; Hirschey MD
[Ad] Endereço:Sarah W. Stedman Nutrition and Metabolism Center, Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC 27710, USA; Division of Endocrinology, Metabolism, and Nutrition, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.
[Ti] Título:A Class of Reactive Acyl-CoA Species Reveals the Non-enzymatic Origins of Protein Acylation.
[So] Source:Cell Metab;25(4):823-837.e8, 2017 Apr 04.
[Is] ISSN:1932-7420
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The mechanisms underlying the formation of acyl protein modifications remain poorly understood. By investigating the reactivity of endogenous acyl-CoA metabolites, we found a class of acyl-CoAs that undergo intramolecular catalysis to form reactive intermediates that non-enzymatically modify proteins. Based on this mechanism, we predicted, validated, and characterized a protein modification: 3-hydroxy-3-methylglutaryl(HMG)-lysine. In a model of altered HMG-CoA metabolism, we found evidence of two additional protein modifications: 3-methylglutaconyl(MGc)-lysine and 3-methylglutaryl(MG)-lysine. Using quantitative proteomics, we compared the "acylomes" of two reactive acyl-CoA species, namely HMG-CoA and glutaryl-CoA, which are generated in different pathways. We found proteins that are uniquely modified by each reactive metabolite, as well as common proteins and pathways. We identified the tricarboxylic acid cycle as a pathway commonly regulated by acylation and validated malate dehydrogenase as a key target. These data uncover a fundamental relationship between reactive acyl-CoA species and proteins and define a new regulatory paradigm in metabolism.
[Mh] Termos MeSH primário: Acil Coenzima A/metabolismo
Proteínas/metabolismo
[Mh] Termos MeSH secundário: Acilação
Anidridos/metabolismo
Biocatálise
Ciclo do Ácido Cítrico
Lisina/metabolismo
Metaboloma
Mitocôndrias/metabolismo
Processamento de Proteína Pós-Traducional
Proteômica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acyl Coenzyme A); 0 (Anhydrides); 0 (Proteins); 1553-55-5 (3-hydroxy-3-methylglutaryl-coenzyme A); 3131-84-8 (glutaryl-coenzyme A); 604-98-8 (succinyl-coenzyme A); K3Z4F929H6 (Lysine)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170713
[Lr] Data última revisão:
170713
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170406
[St] Status:MEDLINE


  3 / 1782 MEDLINE  
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[PMID]:28235427
[Au] Autor:Kamath PR; Sunil D; Das S; Abdul Salam AA; Rao BS
[Ad] Endereço:Department of Chemistry, Manipal Institute of Technology, Manipal University, 576 104, Karnataka, India.
[Ti] Título:Efficient T3P mediated synthesis, differential cytotoxicity and apoptosis induction by indolo-triazolo-thiadiazoles in human breast adenocarcinoma cells.
[So] Source:Chem Biol Interact;268:53-67, 2017 Apr 25.
[Is] ISSN:1872-7786
[Cp] País de publicação:Ireland
[La] Idioma:eng
[Ab] Resumo:The limited efficacy of marketed anticancer agents demands the design of novel target-specific hybrid molecules incorporating multiple bioactive pharmacores to combat cancer. In the present study, a one-pot simple and efficient T3P mediated procedure for the preparation of twelve new 3-(substituted- [1,2,4]triazolo[3,4-b] [1,3,4]thiadiazolo)-1H-indoles with short reaction times, easy workup procedure, good yields, and purity of products is described. Cytotoxicity assay (MTT), flow-cytometric univariate cell cycle analysis, Annexin V-FITC staining and DNA fragmentation for cell death mechanism suggested that compound 3d with chloro-substituted phenyl ring induced enhanced cytotoxicity by an apoptotic pathway with high differential toxicity to breast adenocarcinoma cells (MCF-7) when compared with normal human dermal fibroblast cells. Additionally, the interaction between the BH3 domain of anti-apoptotic proteins Bcl-2 and Bcl-xL with the pharmacophore 3d was examined by molecular docking simulations to assess its potential to induce apoptosis. The docking solutions were proposed to explain the observed selectivity of 3d to Bcl-xL protein. From the present findings, the lead compound, 3d exhibited better anticancer activity when related to the other synthesized molecules with specific action on MCF-7 cells and hence can be considered as a plausible candidate chemo-therapeutic agent, although this warrants further experimentation.
[Mh] Termos MeSH primário: Adenocarcinoma/tratamento farmacológico
Anidridos/química
Antineoplásicos/farmacologia
Apoptose/efeitos dos fármacos
Neoplasias da Mama/tratamento farmacológico
Indóis/farmacologia
Organofosfonatos/química
Tiadiazóis/farmacologia
Triazóis/farmacologia
[Mh] Termos MeSH secundário: Antineoplásicos/síntese química
Antineoplásicos/química
Fragmentação do DNA/efeitos dos fármacos
Feminino
Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos
Química Verde
Seres Humanos
Indóis/síntese química
Indóis/química
Ligantes
Células MCF-7/efeitos dos fármacos
Simulação de Acoplamento Molecular
Proteínas Proto-Oncogênicas c-bcl-2/química
Relação Estrutura-Atividade
Tiadiazóis/síntese química
Tiadiazóis/química
Triazóis/síntese química
Triazóis/química
Proteína bcl-X/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anhydrides); 0 (Antineoplastic Agents); 0 (BCL2 protein, human); 0 (BCL2L1 protein, human); 0 (Indoles); 0 (Ligands); 0 (Organophosphonates); 0 (Proto-Oncogene Proteins c-bcl-2); 0 (Thiadiazoles); 0 (Triazoles); 0 (bcl-X Protein); 0 (propylphosphonic acid anhydride)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170425
[Lr] Data última revisão:
170425
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170226
[St] Status:MEDLINE


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[PMID]:28126516
[Au] Autor:Gajdács M; Spengler G; Sanmartín C; Marc MA; Handzlik J; Domínguez-Álvarez E
[Ad] Endereço:Department of Medical Microbiology and Immunobiology, Faculty of Medicine, University of Szeged, Dóm tér 10, 6720 Szeged, Hungary.
[Ti] Título:Selenoesters and selenoanhydrides as novel multidrug resistance reversing agents: A confirmation study in a colon cancer MDR cell line.
[So] Source:Bioorg Med Chem Lett;27(4):797-802, 2017 Feb 15.
[Is] ISSN:1464-3405
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Taking into account that multidrug resistance (MDR) is the main cause for chemotherapeutic failure in cancer treatment and as a continuation of our efforts to overcome this problem we report the evaluation of one cyclic selenoanhydride (1) and ten selenoesters (2-11) in MDR human colon adenocarcinoma Colo 320 cell line. The most potent derivatives (1, 9-11) inhibited the ABCB1 efflux pump much stronger than the reference compound verapamil. Particularly, the best one (9) was 4-fold more potent than verapamil at a 10-fold lower concentration. Furthermore, the evaluated derivatives exerted a potent and selective cytotoxic activity. In addition, they were strong apoptosis inducers as the four derivatives triggered apoptotic events in a 64-72% of the examined MDR Colo 320 human adenocarcinoma cells.
[Mh] Termos MeSH primário: Anidridos/química
Antineoplásicos/química
Ésteres/química
Compostos Organosselênicos/química
[Mh] Termos MeSH secundário: Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo
Antineoplásicos/metabolismo
Antineoplásicos/farmacologia
Apoptose/efeitos dos fármacos
Linhagem Celular Tumoral
Neoplasias do Colo/metabolismo
Neoplasias do Colo/patologia
Resistência a Medicamentos Antineoplásicos/efeitos dos fármacos
Seres Humanos
Compostos Organosselênicos/metabolismo
Compostos Organosselênicos/farmacologia
Ligação Proteica
Relação Estrutura-Atividade
Verapamil/metabolismo
Verapamil/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (ABCB1 protein, human); 0 (ATP Binding Cassette Transporter, Sub-Family B); 0 (Anhydrides); 0 (Antineoplastic Agents); 0 (Esters); 0 (Organoselenium Compounds); CJ0O37KU29 (Verapamil)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170128
[St] Status:MEDLINE


  5 / 1782 MEDLINE  
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[PMID]:28068545
[Au] Autor:Seetharaman G; Kallar AR; Vijayan VM; Muthu J; Selvam S
[Ad] Endereço:Polymer Science Division, BMT Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram 695012, Kerala, India.
[Ti] Título:Design, preparation and characterization of pH-responsive prodrug micelles with hydrolyzable anhydride linkages for controlled drug delivery.
[So] Source:J Colloid Interface Sci;492:61-72, 2017 04 15.
[Is] ISSN:1095-7103
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:We report a new prodrug micelle-based approach in which a model hydrophobic non-steroidal anti-inflammatory drug (NSAID), ibuprofen (Ibu), is tethered to amphiphilic methoxy polyethylene glycol-polypropylene fumarate (mPEG-PPF) diblock copolymer via hydrolytic anhydride linkages for potential controlled release applications of NSAIDs. Synthesized mPEG-PPF-Ibu polymer drug conjugates (PDCs) demonstrated high drug conjugation efficiency (∼90%) and self-assembled to form micellar nanostructures in aqueous medium with critical micelle concentrations ranging between 16 and 30µg/mL. The entrapment efficiency of Ibu in prepared PDC micelles was as high as 18% (w/w). Crosslinking of prodrug micelles with N,N'-dimethylaminoethyl methacrylate conferred pH-responsive characteristics. pH-responsive PDC micelles averaged 100nm in size at pH 7.4 and exhibited concomitant changes in size upon incubation in physiologically relevant mildly acidic conditions. Ibu release was observed to increase with increasing acidic conditions and could be controlled by varying the amount of crosslinker used. Furthermore, the prepared mPEG-PPF-based micelles demonstrated excellent cytocompatibility and cellular internalization in vitro. More importantly, PDC micelles exerted anti-inflammatory effects by significantly decreasing monosodium urate crystal-induced prostaglandin E2 levels in rabbit synoviocyte cultures in vitro. Cumulatively, our results indicate that this new prodrug micelle approach is promising for NSAID-based therapies in the treatment of arthritis and cancer.
[Mh] Termos MeSH primário: Liberação Controlada de Fármacos
Ibuprofeno/administração & dosagem
Ibuprofeno/química
Micelas
Pró-Fármacos/administração & dosagem
[Mh] Termos MeSH secundário: Anidridos/química
Animais
Anti-Inflamatórios não Esteroides/administração & dosagem
Anti-Inflamatórios não Esteroides/química
Anti-Inflamatórios não Esteroides/farmacologia
Linhagem Celular
Sobrevivência Celular/efeitos dos fármacos
Portadores de Fármacos
Fumaratos/química
Células HeLa
Seres Humanos
Concentração de Íons de Hidrogênio
Hidrólise
Interações Hidrofóbicas e Hidrofílicas
Ibuprofeno/farmacologia
Nanopartículas/química
Polietilenoglicóis/síntese química
Polietilenoglicóis/química
Polietilenoglicóis/farmacologia
Polipropilenos/síntese química
Polipropilenos/farmacologia
Pró-Fármacos/síntese química
Pró-Fármacos/química
Pró-Fármacos/farmacologia
Coelhos
Solubilidade
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anhydrides); 0 (Anti-Inflammatory Agents, Non-Steroidal); 0 (Drug Carriers); 0 (Fumarates); 0 (Micelles); 0 (Polypropylenes); 0 (Prodrugs); 0 (methoxy polyethylene glycol-polypropylene fumarate); 0 (poly(ethylene glycol fumarate)); 30IQX730WE (Polyethylene Glycols); WK2XYI10QM (Ibuprofen)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170713
[Lr] Data última revisão:
170713
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170110
[St] Status:MEDLINE


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[PMID]:27866846
[Au] Autor:Zhao J; Shin Y; Jin Y; Jeong KM; Lee J
[Ad] Endereço:School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea.
[Ti] Título:Determination of enantiomeric vigabatrin by derivatization with diacetyl-l-tartaric anhydride followed by ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1040:199-207, 2017 Jan 01.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Vigabatrin, one of the most widely used antiepileptic drugs, is marketed and administered as a racemic mixture, while only S-enantiomer is therapeutically effective. In the present study, diacetyl-l-tartaric acid anhydride was used as an inexpensive and effective chiral derivatization reagent to produce tartaric acid monoester derivatives of vigabatrin enantiomers that could be readily resolved by reversed phase chromatography. Derivatization conditions were statistically optimized by response surface methodology, resulting in an optimal reaction temperature of 44°C and an optimal reaction time of 30min. The derivatized diastereomers of vigabatrin and internal standard (gabapentin) were analyzed using ultra-high performance liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry. For this analysis, an Agilent ZORBAX Rapid Resolution High Definition Eclipse Plus C18 column (100mm×2.1mm, 1.8µm) was employed for chromatographic separation using 10mM ammonium formate (pH 3.0) and methanol as mobile phase at a flow rate of 0.2mLmin . The established method was validated in terms of specificity, linearity, precision, accuracy, dilution integrity, recovery, matrix effect, stability, and incurred sample reanalysis. It was linear over a range of 0.25-100.0mgL for both S- and R-enantiomers (R ≥0.9987 for both). Intra- and inter-day precisions and accuracies were within acceptable ranges. The method was successfully applied to determine the levels of vigabatrin enantiomers in mouse serum after administration of vigabatrin racemate.
[Mh] Termos MeSH primário: Anticonvulsivantes/sangue
Cromatografia Líquida de Alta Pressão/métodos
Vigabatrina/sangue
[Mh] Termos MeSH secundário: Anidridos/química
Animais
Anticonvulsivantes/análise
Diacetil/química
Masculino
Espectrometria de Massas/métodos
Camundongos Endogâmicos ICR
Estereoisomerismo
Tartaratos/química
Vigabatrina/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE; VALIDATION STUDIES
[Nm] Nome de substância:
0 (Anhydrides); 0 (Anticonvulsants); 0 (Tartrates); GR120KRT6K (Vigabatrin); K324J5K4HM (Diacetyl); W4888I119H (tartaric acid)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170313
[Lr] Data última revisão:
170313
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161122
[St] Status:MEDLINE


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[PMID]:27709801
[Au] Autor:Rocha Â; Teixeira R; Lourenço NM; Afonso CA
[Ad] Endereço:Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001, Lisboa, Portugal.
[Ti] Título:Enzymatic Kinetic Resolution of Secondary Alcohols Using an Ionic Anhydride Generated In Situ.
[So] Source:ChemSusChem;10(1):296-302, 2017 Jan 10.
[Is] ISSN:1864-564X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:We developed a method for the resolution of secondary alcohols using an ionic anhydride acylating agent prepared directly in the reaction medium containing the biocatalyst Candida antarctica lipase B (CALB). NMR studies showed that mixing all components at the same time does not interfere with the coupling reaction or the enzymatic activity. After optimization of the reaction conditions, the method allowed the resolution of a number of substrates in very high conversions (46-48 %) and enantiomeric ratios (E>170) along with an easy recovery of both enantiomers without the need for preparative chromatographic separation. Additionally, both the starting ionic acid and the biocatalyst could be recovered and reused up to nine cycles without significant loss of enantioselectivity.
[Mh] Termos MeSH primário: Álcoois/química
Anidridos/química
Proteínas Fúngicas/metabolismo
Lipase/metabolismo
[Mh] Termos MeSH secundário: Acilação
Biocatálise
Cinética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alcohols); 0 (Anhydrides); 0 (Fungal Proteins); EC 3.1.1.3 (Lipase); EC 3.1.1.3 (lipase B, Candida antarctica)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170523
[Lr] Data última revisão:
170523
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161007
[St] Status:MEDLINE
[do] DOI:10.1002/cssc.201600579


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[PMID]:27687638
[Au] Autor:Chinisaz M; Ebrahim-Habibi A; Dehpour AR; Yaghmaei P; Parivar K; Moosavi-Movahedi AA
[Ad] Endereço:Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran; Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran.
[Ti] Título:Structure and function of anhydride-modified forms of human insulin: In silico, in vitro and in vivo studies.
[So] Source:Eur J Pharm Sci;96:342-350, 2017 Jan 01.
[Is] ISSN:1879-0720
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Insulin is a therapeutic protein whose amyloid formation is reported in diabetic patients. Four anhydride compounds were used in the current study in order to experiment their potential reducing effect on insulin propensity to form amyloid fibrils. The modified forms (obtained with succinic-, 3,3-dimethylglutaric, 2-phenylglutaric-, and (2-Dodecen-1-yl) succinic anhydride), were first characterized with regard to melting temperature (Tm), changes in secondary structure percentage and hydrophobic surface. Fibril formation was then assessed by Congo red absorbance kinetics and transmission electron microscopy. Functionality was investigated with the use of an insulin tolerance test in NMRI mice. Finally, 10ns molecular dynamics simulations were performed during which structural changes, potential energy, gyration radius, RMSD, and accessible surface area were monitored. In all cases, α-helical structure content of the modified forms was reduced, but thermal stability and structural compactness of modified insulin were increased except in case of the dodecenylated species. All modified insulin forms undergo amorphous aggregation instead of amyloid fibrils formation, and dodecenylated insulin makes the largest amorphous aggregates. In silico results were overall in accordance with in vitro studies. Finally, only succinylated insulin was functional, although dimethylglutaric-modified insulin started to show some activity after 2h.
[Mh] Termos MeSH primário: Anidridos/química
Anidridos/farmacologia
Glicemia/efeitos dos fármacos
Simulação por Computador
Insulina/química
Insulina/farmacologia
[Mh] Termos MeSH secundário: Animais
Glicemia/metabolismo
Seres Humanos
Masculino
Camundongos
Distribuição Aleatória
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anhydrides); 0 (Blood Glucose); 0 (Insulin)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170904
[Lr] Data última revisão:
170904
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161001
[St] Status:MEDLINE


  9 / 1782 MEDLINE  
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[PMID]:27650312
[Au] Autor:Sandig B; Buchmeiser MR
[Ad] Endereço:Institut für Polymerchemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
[Ti] Título:Highly Productive and Enantioselective Enzyme Catalysis under Continuous Supported Liquid-Liquid Conditions Using a Hybrid Monolithic Bioreactor.
[So] Source:ChemSusChem;9(20):2917-2921, 2016 Oct 20.
[Is] ISSN:1864-564X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Enzyme-containing ionic liquids (ILs) were immobilized in cellulose-2.5-acetate microbeads particles embedded in a porous monolithic polyurethane matrix. This bioreactor was used under continuous liquid-liquid conditions by dissolving the substrates in a nonpolar organic phase immiscible with the ILs, thereby creating a biphasic system. Lipases (candida antarctica lipase B, CALB, candida rugosa lipase, CRL) were used to catalyze the enantioselective transesterification of racemic (R,S)-1-phenylethanol with vinyl butyrate and vinyl acetate, the esterification of (+/-)-2-isopropyl-5-methylcyclohexanol with propionic anhydride and the amidation of (R,S)-1-phenylethylamine with ethyl methoxyacetate. With this unique setup, very high productivities, that is, turnover numbers (TONs) up to 5.1×10 and space-time yields (STYs) up to 28 g product L h , exceeding the corresponding values for batch-type reactions by a factor of 3100 and 40, respectively, were achieved while maintaining or even enhancing enantioselectivity compared to batch reactions via kinetic resolution. To our best knowledge, this is the first continuously operated bioreactor using supported liquid-liquid conditions that shows these features in the synthesis of chiral esters and amides.
[Mh] Termos MeSH primário: Reatores Biológicos
Lipase/metabolismo
[Mh] Termos MeSH secundário: Anidridos/química
Catálise
Cicloexanonas/química
Esterificação
Fenetilaminas/química
Propionatos/química
Estereoisomerismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (2-isopropyl-5-methylcyclohexanone); 0 (Anhydrides); 0 (Cyclohexanones); 0 (Phenethylamines); 0 (Propionates); E3A2VV18E6 (propionic anhydride); EC 3.1.1.3 (Lipase); HZ9DM6B2MT (1-phenethylamine)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170531
[Lr] Data última revisão:
170531
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160922
[St] Status:MEDLINE
[do] DOI:10.1002/cssc.201600994


  10 / 1782 MEDLINE  
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[PMID]:27566227
[Au] Autor:Mahapatra RD; Dey J
[Ad] Endereço:Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, 721 302, India.
[Ti] Título:Instant gels from mixtures of amines and anhydrides at room temperature.
[So] Source:Colloids Surf B Biointerfaces;147:422-433, 2016 Nov 01.
[Is] ISSN:1873-4367
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:A series of novel two-component organogel systems comprising of amines and anhydrides was developed. These two-component systems in aromatic solvents exhibit instantaneous gelation during mixing at room temperature without the requirement of any external stimulus such as heat, sonication, etc. The corresponding alcohols, however, failed to produce gel under similar condition. The structure-property relationship was investigated. The effect of mixing ratio of the two components as well as the effect of solvents on gelation was studied. A detail characterization of the organogels using electron microscopy, FTIR, (1)H NMR and X-ray diffraction spectroscopy, differential scanning calorimetry and rheology suggested formation of a hydrogen-bonded complex that induces creation of three dimensional entangled network structures which immobilize the solvent showing macroscopic gelation. The packing of hydrocarbon chains of the amines and π-π stacking interaction in aromatic amines were observed to play a decisive role in altering the thermal and mechanical stability of the organogels. The organogels formed by mixing aromatic amines with the anhydride exhibit exceptional thermal and mechanical stability compared to the aliphatic amines.
[Mh] Termos MeSH primário: Aminas/química
Anidridos/química
Géis/química
Tensoativos/química
[Mh] Termos MeSH secundário: Varredura Diferencial de Calorimetria
Ligações de Hidrogênio
Espectroscopia de Ressonância Magnética
Reologia
Temperatura Ambiente
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amines); 0 (Anhydrides); 0 (Gels); 0 (Surface-Active Agents)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170904
[Lr] Data última revisão:
170904
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160828
[St] Status:MEDLINE



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