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Pesquisa : G01.358.500.505.810.500 [Categoria DeCS]
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[PMID]:29318312
[Au] Autor:Sharma V; Jaiswal PK; Yadav DK; Saran M; Prikhodko J; Mathur M; Swami AK; Mashevskaya IV; Chaudhary S
[Ti] Título:Microwave-assisted One-pot Efficient Synthesis of Functionalized 2-Oxo-2-phenylethylidenes-linked 2-Oxobenzo[1,4]oxazines and 2-Oxoquino[1,4]oxalines: Synthetic Applications, Antioxidant Activity, SAR and Cytotoxic Studies.
[So] Source:Acta Chim Slov;64(4):988-1004, 2017 Dec.
[Is] ISSN:1318-0207
[Cp] País de publicação:Slovenia
[La] Idioma:eng
[Ab] Resumo:A microwave-assisted, environmentally benign green protocol for the synthesis of functionalized (Z)-3-(2-oxo-2-phenylethylidene)-3, 4-dihydro-2H-benzo[b][1,4]oxazin-2-ones (11a-n) in excellent yields (upto 97%) and (Z)-3-(2-oxo-2-phenylethylidene)-3,4-dihydroquinoxalin-2(1H)-ones (14a-h) (upto 96% yield) are reported. The practical applicability of developed methodology were also confirmed by the gram scale synthesis of 11a, 14c and 14e; synthesis of anticancer alkaloid Cephalandole A 16 (89% yield). All the synthesized compounds 11a-n, 14a-h and 16 were assessed for their in vitro antioxidant activities in DPPH radical scavenging and FRAP assay. In DPPH assay, compounds 11a, 14c and 14e, the most active compounds of the series, were found to show IC50 value of 10.20 ± 0.08 µg/mL, 9.89 ± 0.15 µg/mL and 8.97 ± 0.13 µg/mL, respectively in comparison with standard reference (ascorbic acid, IC50 = 4.57 µg/mL). Whereas, in FRAP antioxidant assay seven compounds (11c, 11e, 11i, 11k, 11l, 14d and 14h) displayed higher antioxidant activity in comparison to the reference standard BHT (C0.5FRAP = 546.2 µM). Moreover, the cytotoxic studies of the compounds 11a, 14c, 14e and 14h were found to be non-toxic in nature in 3T3 fibroblast cell lines using MTT assay.
[Mh] Termos MeSH primário: Antineoplásicos/síntese química
Antioxidantes/síntese química
Oxazinas/síntese química
Quinoxalinas/síntese química
[Mh] Termos MeSH secundário: Células 3T3
Animais
Antineoplásicos/farmacologia
Antioxidantes/farmacologia
Camundongos
Micro-Ondas
Oxazinas/farmacologia
Quinoxalinas/farmacologia
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antineoplastic Agents); 0 (Antioxidants); 0 (Oxazines); 0 (Quinoxalines)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180306
[Lr] Data última revisão:
180306
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180111
[St] Status:MEDLINE


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[PMID]:29396378
[Au] Autor:Kori S; Parmar A; Goyal J; Sharma S
[Ad] Endereço:Institute of Forensic Science & Criminology, Panjab University, Chandigarh 160 014, India.
[Ti] Título:Cloud point extraction coupled with microwave-assisted back-extraction (CPE-MABE) for determination of Eszopiclone (Z-drug) using UV-Visible, HPLC and mass spectroscopic (MS) techniques: Spiked and in vivo analysis.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1074-1075:129-138, 2018 Feb 01.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:A procedure for the determination of Eszopiclone (ESZ) from complex matrices i.e. in vitro (spiked matrices), as well as in vivo (mice model) was developed using cloud point extraction coupled with microwave-assisted back-extraction (CPE-MABE). Analytical measurements have been carried using UV-Visible, HPLC and MS techniques. The proposed method has been validated according to ICH guidelines and legitimate reproducible and reliability of protocol is assessed through intraday and inter-day precision <3.61% and <4.70%, respectively. Limit of detection has been obtained as 0.083µg/mL and 0.472µg/mL respectively, for HPLC and UV-Visible techniques, corresponding to assessed linearity range. The coaservate phase in CPE was back extracted under microwaves exposure, with isooctane at pre-concentration factor ~50 when 5mL of sample solution was pre-concentrated to 0.1mL. Under optimized conditions i.e. Aqueous-Triton X-114 4% (w/v), pH4.0, NaCl 4% (w/v) and equilibrium temperature of 45°C for 20min, average extraction recovery has been obtained between 89.8 and 99.2% and 84.0-99.2% from UV-Visible and HPLC analysis, respectively. The method has been successfully applied to the pharmacokinetic estimation (post intraperitoneal administration) of ESZ in mice. MS analysis precisely depicted the presence of active N­desmethyl zopiclone in impales as well as in mice plasma.
[Mh] Termos MeSH primário: Cromatografia Líquida de Alta Pressão/métodos
Zopiclona/análise
Espectrometria de Massas/métodos
[Mh] Termos MeSH secundário: Animais
Fracionamento Químico
Zopiclona/química
Zopiclona/isolamento & purificação
Zopiclona/farmacocinética
Seres Humanos
Concentração de Íons de Hidrogênio
Limite de Detecção
Modelos Lineares
Masculino
Camundongos
Camundongos Endogâmicos BALB C
Micro-Ondas
Leite/química
Polietilenoglicóis
Reprodutibilidade dos Testes
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
30IQX730WE (Polyethylene Glycols); 9036-19-5 (Nonidet P-40); UZX80K71OE (Eszopiclone)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180204
[St] Status:MEDLINE


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[PMID]:29232606
[Au] Autor:Kotnala A; Senthilkumari S; Halder N; Kumar A; Velpandian T
[Ad] Endereço:Ocular Pharmacology & Pharmacy Division, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
[Ti] Título:Microwave assisted synthesis for A2E and development of LC-ESI-MS method for quantification of ocular bisretinoids in human retina.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1073:10-18, 2018 Jan 15.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:PURPOSE: To develop a microwave assisted method for the rapid synthesis of A2E and also to develop a method to quantify N-retinylidene-N-retinylethanolamine(A2E), all-trans retinal dimer (ATRD), A2-glycerophospho ethanolamine (A2GPE), dihydropyridine phosphatidyl ethanolamine (A2DHPE) and monofuran A2E (MFA2E) in age matched retina. METHODS: The development of microwave assisted synthesis of A2E, its purification and characterization for its utility in quantification in human retina. The semi-quantitative method development using LC-ESI-MS, LC-ESI-MS/MS and LC-APCI-MS/MS from pooled macula and peripheral retina for the bisretinoid analysis has been done. RESULTS: Maximum A2E conversion using microwave assisted process took place at 80°C for 45min with a yield of 55.01%. Highly sensitive and specific mass spectrometric method was developed using reverse phase C-18 separation with positive electrospray ionization and positive atmospheric phase chemical ionization of tandom mass spectrometry. A gradient mobile phase separation was achieved using water and methanol with 0.1% TFA. Multiple reaction monitoring acquisition for ESI and APCI was performed at ATRD m/z 551.2/522.2, A2GPE m/z 746.4/729.5, A2DHPEm/z 594.4/576.5, MFA2E m/z 608.2/591.2, A2E m/z 592.4/418.2. Method was validated using LC-ESI-SIM mode to determine selectivity, linearity, sensitivity, precision and accuracy. CONCLUSION: An attempt towards optimization of the synthetic procedure of A2E was made so as to reduce the lengthy reaction time without compromising the yield. Developed method was capable enough for the detection of low level of bisretinids in retina.
[Mh] Termos MeSH primário: Cromatografia Líquida/métodos
Micro-Ondas
Retina/química
Retinoides/análise
Retinoides/síntese química
Espectrometria de Massas por Ionização por Electrospray/métodos
[Mh] Termos MeSH secundário: Adulto
Idoso
Seres Humanos
Masculino
Meia-Idade
Retinoides/química
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (A2-E (N-retinylidene-N-retinylethanolamine)); 0 (Retinoids)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180302
[Lr] Data última revisão:
180302
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171213
[St] Status:MEDLINE


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[PMID]:28746408
[Au] Autor:Cantres-Rosario YM; Acevedo-Mariani FM; Pérez-Laspiur J; Haskins WE; Plaud M; Cantres-Rosario YM; Skolasky R; Méndez-Bermúdez I; Wojna V; Meléndez LM
[Ad] Endereço:Department of Microbiology and Medical Zoology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico.
[Ti] Título:Microwave & magnetic proteomics of macrophages from patients with HIV-associated cognitive impairment.
[So] Source:PLoS One;12(7):e0181779, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:OBJECTIVE: HIV-infected monocytes can infiltrate the blood brain barrier as differentiated macrophages to the central nervous system, becoming the primary source of viral and cellular neurotoxins. The final outcome is HIV-associated cognitive impairment (HACI), which remain prevalent today, possibly due to the longer life-span of the patients treated with combined anti-retroviral therapy. Our main goal was to characterize the proteome of monocyte-derived macrophages (MDM) from HACI patients, and its association with their cognitive status, to find novel targets for therapy. METHODS: MDM were isolated from the peripheral blood of 14 HIV-seropositive women characterized for neurocognitive function, including: four normal cognition (NC), five asymptomatic (A), and five with cognitive impaired (CI). Proteins from macrophage lysates were isobaric-labeled with the microwave and magnetic (M2) sample preparation method followed by liquid chromatography-tandem mass spectrometry-based protein identification and quantification. Differences in protein abundance across groups classified by HACI status were determined using analysis of variance. RESULTS: A total of 2,519 proteins were identified with 2 or more peptides and 28 proteins were quantified as differentially expressed. Statistical analysis revealed increased abundance of 17 proteins in patients with HACI (p<0.05), including several enzymes associated to the glucose metabolism. Western blot confirmed increased expression of 6-Phosphogluconate dehydrogenase and L-Plastin in A and CI patients over NC and HIV seronegatives. CONCLUSIONS: This is the first quantitative proteomics study exploring the changes in protein abundance of macrophages isolated from patients with HACI. Further studies are warranted to determine if these proteins may be target candidates for therapy development against HACI.
[Mh] Termos MeSH primário: Transtornos Cognitivos/metabolismo
Infecções por HIV/metabolismo
Macrófagos/metabolismo
Proteoma/análise
Proteômica/métodos
[Mh] Termos MeSH secundário: Análise de Variância
Western Blotting
Células Cultivadas
Cromatografia Líquida
Transtornos Cognitivos/complicações
Estudos de Coortes
Estudos Transversais
Feminino
Infecções por HIV/complicações
Seres Humanos
Magnetismo
Micro-Ondas
Mapas de Interação de Proteínas
Proteoma/metabolismo
Proteômica/instrumentação
Espectrometria de Massas em Tandem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Proteome)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0181779


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[PMID]:29248298
[Au] Autor:Chatkewitz LE; Halonski JF; Padilla MS; Young DD
[Ad] Endereço:Department of Chemistry, College of William & Mary, P.O. Box 8795, Williamsburg, VA 23187 USA.
[Ti] Título:Investigation of copper-free alkyne/azide 1,3-dipolar cycloadditions using microwave irradiation.
[So] Source:Bioorg Med Chem Lett;28(2):81-84, 2018 01 15.
[Is] ISSN:1464-3405
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The prevalence of 1,3-dipolar cycloadditions of azides and alkynes within both biology and chemistry highlights the utility of these reactions. However, the use of a copper catalyst can be prohibitive to some applications. Consequently, we have optimized a copper-free microwave-assisted reaction to alleviate the necessity for the copper catalyst. A small array of triazoles was prepared to examine the scope of this approach, and the methodology was translated to a protein context through the use of unnatural amino acids to demonstrate one of the first microwave-mediated bioconjugations involving a full length protein.
[Mh] Termos MeSH primário: Alquinos/química
Azidas/química
Micro-Ondas
Triazóis/síntese química
[Mh] Termos MeSH secundário: Reação de Cicloadição
Modelos Moleculares
Estrutura Molecular
Triazóis/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alkynes); 0 (Azides); 0 (Triazoles)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180216
[Lr] Data última revisão:
180216
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171218
[St] Status:MEDLINE


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[PMID]:29195214
[Au] Autor:Murugesan B; Sonamuthu J; Pandiyan N; Pandi B; Samayanan S; Mahalingam S
[Ad] Endereço:Advanced Green Chemistry Lab, Department of Industrial Chemistry, School of Chemical Sciences, Alagappa University, Karaikudi 630 003, Tamil Nadu, India.
[Ti] Título:Photoluminescent reduced graphene oxide quantum dots from latex of Calotropis gigantea for metal sensing, radical scavenging, cytotoxicity, and bioimaging in Artemia salina: A greener route.
[So] Source:J Photochem Photobiol B;178:371-379, 2018 Jan.
[Is] ISSN:1873-2682
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:In this work, we report the fabrication of green fluorescent reduced graphene oxide quantum dots (rGOQDs) from the latex of Calotropis gigantea by simple one-step microwave assisted greener route. The latex of Calotropis gigantea calcined at 300°C and its ethanolic extract is used for the synthesis of QDs, The rGOQDs showed particle size ranging from 2 to 8nm and it exhibited green fluorescent in longer UV region at 360-520nm. The rGOQDs graphitic nature was confirmed by RAMAN and XRD analysis. The FTIR, XPS demonstrate that presence of functional groups such as CO, COC, -OH, hence it's addressing them as rGOQDs. It is used to design the greener and economically adopted fluorescent probe for the detection of Pb ions. It provides simple and appropriate for the selective and sensitive detection of Pb ions in water purification process. It also trapped the free radicals and neutralized that and act as an excellent radical scavenger in DPPH radical scavenging assessment. These rGOQDs showed excellent biocompatibility on brine shrimp nauplii (Artemia salina) up to 160µg/mL for 24h incubation. Furthermore, rGOQDS were demonstrated as fluorescent bioimaging probe selectively in the inner digestion part of Artemia salina. In summary, stable, economically viable, highly biocompatible, greener method based rGOQDs were prepared for heavy metal ion detecting, radical scavenging, bioimaging applications which can play a vital role in the future nanotechnology-based biomedical field.
[Mh] Termos MeSH primário: Artemia/metabolismo
Calotropis/química
Depuradores de Radicais Livres/química
Grafite/química
Pontos Quânticos/química
[Mh] Termos MeSH secundário: Animais
Artemia/química
Artemia/efeitos dos fármacos
Materiais Biocompatíveis/química
Materiais Biocompatíveis/toxicidade
Calotropis/metabolismo
Técnicas Eletroquímicas
Corantes Fluorescentes/química
Íons/química
Látex/química
Chumbo/análise
Microscopia Eletrônica de Transmissão
Microscopia de Fluorescência
Micro-Ondas
Óxidos/química
Tamanho da Partícula
Pontos Quânticos/toxicidade
Espectroscopia de Infravermelho com Transformada de Fourier
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biocompatible Materials); 0 (Fluorescent Dyes); 0 (Free Radical Scavengers); 0 (Ions); 0 (Latex); 0 (Oxides); 2P299V784P (Lead); 7782-42-5 (Graphite)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171202
[St] Status:MEDLINE


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[PMID]:29363926
[Au] Autor:Kodentsova VM; Kochetkova AA; Risnik DV; Sarkisyan VA; Bessonov VV
[Ti] Título:[The effect of microwaves on the fat component and preserve vitamins in foods].
[So] Source:Vopr Pitan;84(5):16-30, 2015.
[Is] ISSN:0042-8833
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Mh] Termos MeSH primário: Culinária/métodos
Gorduras na Dieta
Gorduras/química
Micro-Ondas
Valor Nutritivo
Vitamina E/química
[Mh] Termos MeSH secundário: Seres Humanos
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Dietary Fats); 0 (Fats); 1406-18-4 (Vitamin E)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180205
[Lr] Data última revisão:
180205
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180125
[St] Status:MEDLINE


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[PMID]:27775555
[Au] Autor:Chretiennot T; Dubuc D; Grenier K
[Ad] Endereço:LAAS-CNRS, Université de Toulouse, CNRS, Toulouse 31031, France. thomas.chretiennot@gmail.com.
[Ti] Título:Microwave-Based Microfluidic Sensor for Non-Destructive and Quantitative Glucose Monitoring in Aqueous Solution.
[So] Source:Sensors (Basel);16(10), 2016 Oct 19.
[Is] ISSN:1424-8220
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:This paper presents a reliable microwave and microfluidic miniature sensor dedicated to the measurement of glucose concentration in aqueous solution. The device; which is integrated with microtechnologies; is made of a bandstop filter implemented in a thin film microstrip technology combined with a fluidic microchannel. Glucose aqueous solutions have been characterized for concentration ranging from 80 g/L down to 0.3 g/L and are identified with the normalized insertion loss at optimal frequency. The sensitivity of the sensor has consequently been estimated at 7.6 × 10 dB/(g/L); together with the experimental uncertainty; the resolution of the sensor comes to 0.4 g/L. These results demonstrate the potentialities of such a sensor for the quantitative analysis of glucose in aqueous solution.
[Mh] Termos MeSH primário: Glucose/análise
Microfluídica/métodos
Micro-Ondas
Água/química
[Mh] Termos MeSH secundário: Seres Humanos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
059QF0KO0R (Water); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180205
[Lr] Data última revisão:
180205
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161025
[St] Status:MEDLINE


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[PMID]:28456355
[Au] Autor:Chiang J; Nickel K; Kimple RJ; Brace CL
[Ad] Endereço:Department of Radiology, University of Wisconsin, 1111 Highland Ave., 1310-O, Madison, WI 53705. Electronic address: cjchiang@wisc.edu.
[Ti] Título:Potential Mechanisms of Vascular Thrombosis after Microwave Ablation in an in Vivo Liver.
[So] Source:J Vasc Interv Radiol;28(7):1053-1058, 2017 Jul.
[Is] ISSN:1535-7732
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:PURPOSE: To evaluate potential biologic and thermal mechanisms of the observed differences in thrombosis rates between hepatic vessels during microwave (MW) ablation procedures. MATERIALS AND METHODS: MW ablation antennae were placed in single liver lobes of 2 in vivo porcine liver models (n = 3 in each animal; N = 6 total) in the proximity of a large (> 5 mm) portal vein (PV) and hepatic veins (HVs). Each ablation was performed with 100 W for 5 minutes. Conventional ultrasound imaging and intravascular temperature probes were used to evaluate vessel patency and temperature changes during the ablation procedure. Vascular endothelium was harvested 1 hour after ablation and used to characterize genes and proteins associated with thrombosis in PVs and HVs. RESULTS: Targeted PVs within the MW ablation zone exhibited thrombosis at a significantly higher rate than HVs (54.5% vs 0.0%; P = .0046). There was a negligible change in intravascular temperature in PVs and HVs during the ablation procedure (0.2°C ± 0.4 vs 0.6°C ± 0.9; P = .46). PVs exhibited significantly higher gene expression than HVs in terms of fold differences in thrombomodulin (2.9 ± 2.0; P = .0001), von Willebrand factor (vWF; 7.6 ± 1.5; P = .0001), endothelial protein C receptor (3.50 ± 0.49; P = .0011), and plasminogen activator inhibitor (1.46 ± 0.05; P = .0014). Western blot analysis showed significantly higher expression of vWF (2.32 ± 0.92; P = .031) in PVs compared with HVs. CONCLUSIONS: Large PVs exhibit thrombosis more frequently than HVs during MW ablation procedures. Biologic differences in thrombogenicity, rather than heat transfer, between PVs and HVs may contribute to their different rates of thrombosis.
[Mh] Termos MeSH primário: Técnicas de Ablação/métodos
Veias Hepáticas/cirurgia
Fígado/irrigação sanguínea
Fígado/cirurgia
Micro-Ondas
Veia Porta/cirurgia
Trombose/etiologia
[Mh] Termos MeSH secundário: Animais
Biomarcadores/sangue
Western Blotting
Fígado/diagnóstico por imagem
Suínos
Temperatura Ambiente
Ultrassonografia/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biomarkers)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:180117
[Lr] Data última revisão:
180117
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170501
[St] Status:MEDLINE


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[PMID]:29199259
[Au] Autor:Nakao M
[Ad] Endereço:Graduate School of Pharmaceutical Sciences, Tokushima University.
[Ti] Título:[Development of Novel Functional Molecules Based on the Molecular Structure Characteristics of Diketopiperazines].
[So] Source:Yakugaku Zasshi;137(12):1505-1516, 2017.
[Is] ISSN:1347-5231
[Cp] País de publicação:Japan
[La] Idioma:jpn
[Ab] Resumo:This article focuses on our investigation of the molecular structure characteristics of diketopiperazines (DKPs), and application of these findings to the development of novel functional molecules. DKPs bearing a benzyl moiety are known to adopt a folded conformation, in which the benzyl moiety is folded over the DKP ring. In order to investigate the driving force behind the folded conformation, we synthesized DKPs bearing a benzyl moiety with different para-substituents, and demonstrated that the folded conformation likely arose from intramolecular CH/π interactions, based on the electronic effects of para-substituents on the benzyl group in H NMR spectroscopy. On the other hand, N4-methylation of DKPs bearing a benzyl moiety was found to change their folded conformation to an extended conformation, based on single crystal X-ray crystallography and H NMR spectroscopy analysis. Next, we attempted to synthesize both hydroxamate-type siderophores containing the DKP ring: rhodotorulic acid and erythrochelin. Facile synthesis of rhodotorulic acid and its N,N'-dimethylated derivative was achieved by microwave-assisted cyclization of the corresponding dipeptide precursors. Interestingly, N,N'-dimethylated rhodotorulic acid was found to be more soluble in various organic solvents than rhodotorulic acid. Moreover, erythrochelin was synthesized for the first time, and its metal-chelating ability with not only Fe(III) but also Mg(II) was confirmed based on electrospray ionization mass spectrometry (ESI-MS) analysis. Finally, we synthesized DKPs bearing a primary amino group, and found that they could catalyze the asymmetric aldol reaction between hydroxyacetone and p-nitrobenzaldehyde.
[Mh] Termos MeSH primário: Dicetopiperazinas/química
Dicetopiperazinas/síntese química
Conformação Molecular
[Mh] Termos MeSH secundário: Aldeídos/química
Catálise
Quelantes
Cristalografia por Raios X
Ciclização
Espectroscopia de Ressonância Magnética
Metilação
Micro-Ondas
Oligopeptídeos/síntese química
Fenômenos de Química Orgânica
Piperazinas/síntese química
Solventes
Espectrometria de Massas por Ionização por Electrospray
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Aldehydes); 0 (Chelating Agents); 0 (Diketopiperazines); 0 (Oligopeptides); 0 (Piperazines); 0 (Solvents); 0 (erythrochelin); 61F3VBQ4G5 (rhodotorulic acid); 8C6G962B53 (3-hydroxybutanal)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180112
[Lr] Data última revisão:
180112
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171205
[St] Status:MEDLINE
[do] DOI:10.1248/yakushi.17-00176



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