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1.
J Med Chem ; 62(13): 6063-6082, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31257875

RESUMO

(E)-3,4-Dihydroxybenzylideneacetone (compound 1) inhibited receptor activator of NF-κB ligand-induced osteoclastogenesis of C57BL/6 bone marrow monocyte/macrophages with IC50 of 7.8 µM (IC50 of alendronate, 3.7 µM) while stimulating the differentiation of MC3T3-E1 osteoblastic cells, accompanied by the induction of Runt-related transcription factor 2, alkaline phosphatase, and osteocalcin. (E)-4-(3-Hydroxy-4-methoxyphenyl)-3-buten-2-one (compound 2c) showed a dramatically increased osteoclast-inhibitory potency with IC50 of 0.11 µM while sustaining osteoblast-stimulatory activity. (E)-4-(4-Hydroxy-3-methoxyphenyl)-3-buten-2-one (compound 2g) stimulated alkaline phosphatase production 2-fold at 50 µM without changing osteoclast-inhibitory activity, compared with compound 1. Oral administration of compounds 1, 2c, and 2g prevented ovariectomy-induced osteoporosis in ddY mice to a degree proportional to their osteoclastogenesis-inhibitory potencies. The administration of 1 (mg/kg)/d compound 2c ameliorated histomorphometry of osteoporotic bone to a degree comparable with 10 (mg/kg)/d alendronate. Conclusively, the in vitro capacity of a few benzylideneacetone derivatives to inhibit osteoclastogenesis supported by independent osteoblastogenesis activation was convincingly reflected in in vivo management of osteoporosis, suggesting a potential novel therapeutics for osteopenic diseases.


Assuntos
Compostos de Benzilideno/uso terapêutico , Butanonas/uso terapêutico , Osteogênese/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Compostos de Benzilideno/síntese química , Compostos de Benzilideno/farmacocinética , Butanonas/síntese química , Butanonas/farmacocinética , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Feminino , Fêmur/patologia , Humanos , Camundongos , Estrutura Molecular , Subunidade p50 de NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Osteoclastos/metabolismo , Osteoporose/tratamento farmacológico , Células RAW 264.7 , Relação Estrutura-Atividade , Tíbia/patologia
2.
J Org Chem ; 84(11): 6982-6991, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31066559

RESUMO

Polyhydroxylated compounds are building blocks for the synthesis of carbohydrates and other natural products. Their synthesis is mainly achieved by different synthetic versions of aldol-coupling reactions, catalyzed either by organocatalysts, enzymes, or metal-organic catalysts. We have investigated the formation of 1,4-substituted 2,3-dihydroxybutan-1-one derivatives from para- and meta-substituted phenylacetaldehydes by three distinctly different strategies. The first involved a direct aldol reaction with hydroxyacetone, dihydroxyacetone, or 2-hydroxyacetophenone, catalyzed by the cinchona derivative cinchonine. The second was reductive cross-coupling with methyl- or phenylglyoxal promoted by SmI2, resulting in either 5-substituted 3,4-dihydroxypentan-2-ones or 1,4 bis-phenyl-substituted butanones, respectively. Finally, in the third case, aldolase catalysis was employed for synthesis of the corresponding 1,3,4-trihydroxylated pentan-2-one derivatives. The organocatalytic route with cinchonine generated distereomerically enriched syn-products (de = 60-99%), with moderate enantiomeric excesses (ee = 43-56%) but did not produce aldols with either hydroxyacetone or dihydroxyacetone as donor ketones. The SmI2-promoted reductive cross-coupling generated product mixtures with diastereomeric and enantiomeric ratios close to unity. This route allowed for the production of both 1-methyl- and 1-phenyl-substituted 2,3-dihydroxybutanones at yields between 40-60%. Finally, the biocatalytic approach resulted in enantiopure syn-(3 R,4 S) 1,3,4-trihydroxypentan-2-ones.


Assuntos
Butanonas/síntese química , Butanonas/metabolismo , Cinchona/química , Frutose-Bifosfato Aldolase/metabolismo , Pentanonas/síntese química , Pentanonas/metabolismo , Butanonas/química , Catálise , Estrutura Molecular , Pentanonas/química , Estereoisomerismo
3.
Curr Med Chem ; 26(15): 2601-2608, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30009704

RESUMO

Attachment of different tails to the well-known carbonic anhydrase (CA) pharmacophores has led to the development of several new CA inhibitors (CAIs). A very good example of such "tails" is constituted by carbohydrates, which represent a wide range of chemotypes, leading thus to a high number of new CAIs. In the last years, several C-cinnamoyl glycosides containing different scaffolds have been prepared and investigated as carbonic anhydrase inhibitors, showing that some of them are very potent and selective CAIs. This article will review the latest developments in the synthesis and biological activity of these Cglycosides.


Assuntos
Butanonas/química , Inibidores da Anidrase Carbônica/química , Glicosídeos/química , Antituberculosos/síntese química , Antituberculosos/química , Bactérias/efeitos dos fármacos , Bactérias/enzimologia , Butanonas/síntese química , Inibidores da Anidrase Carbônica/síntese química , Anidrases Carbônicas/química , Domínio Catalítico , Glicosídeos/síntese química , Humanos , Estrutura Molecular
4.
Chem Commun (Camb) ; 54(47): 6000-6003, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29796466
5.
Bioorg Chem ; 72: 359-366, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28302311

RESUMO

The first synthesis of (E)-4-(3-bromo-4,5-dihydroxyphenyl)but-3-en-2-one (1), (E)-4-(2-bromo-4,5-dihydroxyphenyl)but-3-en-2-one (2), and (E)-4-(2,3-dibromo-4,5-dihydroxyphenyl)but-3-en-2-one (3) was realized as natural bromophenols. Derivatives with mono OMe of 2 and 3 were obtained from the reactions of their derivatives with di OMe with AlCl3. These novel 4-phenylbutenone derivatives were effective inhibitors of the cytosolic carbonic anhydrase I and II isoenzymes (hCA I and II), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with Ki values in the range of 158.07-404.16pM for hCA I, 107.63-237.40pM for hCA II, 14.81-33.99pM for AChE and 5.64-19.30pM for BChE. The inhibitory effects of the synthesized novel 4-phenylbutenone derivatives were compared to acetazolamide as a clinical hCA I and II isoenzymes inhibitor and tacrine as a clinical AChE and BChE enzymes inhibitor.


Assuntos
Produtos Biológicos/farmacologia , Butanonas/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Inibidores da Colinesterase/farmacologia , Fenóis/farmacologia , Acetilcolinesterase/metabolismo , Produtos Biológicos/síntese química , Produtos Biológicos/química , Butanonas/síntese química , Butanonas/química , Butirilcolinesterase/metabolismo , Anidrase Carbônica I/antagonistas & inibidores , Anidrase Carbônica I/metabolismo , Anidrase Carbônica II/antagonistas & inibidores , Anidrase Carbônica II/metabolismo , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Fenóis/síntese química , Fenóis/química , Relação Estrutura-Atividade
6.
Chembiochem ; 18(4): 338-351, 2017 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-27992105

RESUMO

ß-Lactam antibiotics have been used for many years to treat bacterial infections. However the effective treatment of an increasing range of microbial infections is threatened by bacterial resistance to ß-lactams: the prolonged, widespread (and at times reckless) use of these drugs has spawned widespread resistance, which renders them ineffective against many bacterial strains. The cyclobutanone ring system is isosteric with ß-lactam: in cyclobutanone analogues, the eponymous cyclic amide is replaced with an all-carbon ring, the amide N is substituted by a tertiary C-H α to a ketone. Cyclobutanone analogues of various ß-lactam antibiotics have been investigated over the last 35 years, initially as prospective antibiotics in their own right and inhibitors of the ß-lactamase enzymes that impart resistance to ß-lactams. More recently they have been tested as inhibitors of other serine proteases and as mechanistic probes of ß-lactam biosynthesis. Cyclobutanone analogues of the penam ring system are the first reversible inhibitors with moderate activity against all classes of ß-lactamase; other compounds from this family inhibit Streptomyces R61 dd-carboxypeptidase/transpeptidase, human neutrophil elastase and porcine pancreatic elastase. But has their potential as enzyme inhibitors been fully exploited? Challenges in synthesising diversely functionalised cyclobutanone derivatives mean that only a limited number have been made (with limited structural diversity) and evaluated. This review surveys the different synthetic approaches that have been taken to these compounds, the investigations made to evaluate their biological activity and prospects for future developments in this area.


Assuntos
Inibidores de beta-Lactamases/síntese química , beta-Lactamas/química , beta-Lactamas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Butanonas/síntese química , Butanonas/química , Butanonas/farmacologia , Ciclização , Humanos , Inibidores de beta-Lactamases/química , Inibidores de beta-Lactamases/farmacologia
7.
Chemistry ; 22(21): 7033-5, 2016 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-26998826

RESUMO

The terminal bromomethoxydiene (BMD) moiety of the polyhydroxylated chain present in phormidolides and oscillariolides has been synthesized for first time. Several strategies for the stereoselective synthesis of the 4-bromo-3-methoxybut-3-en-2-ones are described. Furthermore, a preliminary study to successfully introduce the BMD within the polyol chain and the fatty acid allowed us to corroborate the end structure of the polyol.


Assuntos
Produtos Biológicos/síntese química , Bromo/química , Butanonas/síntese química , Macrolídeos/síntese química , Produtos Biológicos/química , Butanonas/química , Halogenação , Macrolídeos/química , Estereoisomerismo
8.
Chem Commun (Camb) ; 51(24): 5013-6, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25703698

RESUMO

An efficient metal free self-sorting tandem protocol for stereospecific synthesis of 2-thio-1,4-enediones involving C-C double bond formation via direct coupling of terminal alkynes has been developed. The method was also extended to the first synthesis of ß-thio-γ-keto-α,ß-unsaturated esters via a cross coupling reaction with ethyl glyoxylate. The reaction relies on a first of its kind use of Bronsted and Lewis acids to switch selectivity for the synthesis of an E or a Z-isomer respectively.


Assuntos
Alquinos/química , Butanonas/síntese química , Sulfetos/síntese química , Butanonas/química , Estrutura Molecular , Estereoisomerismo , Sulfetos/química
9.
Chemistry ; 21(3): 1337-42, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-25394565

RESUMO

A regioselective synthesis of symmetrical and unsymmetrical benzopinacolones through aerobic dehydrogenative α-arylation at the tertiary sp(3) C-H bond of substituted 1,1-diphenylketones with aromatic and heteroaromatic compounds, in the presence of K2S2O8 in CF3COOH at room temperature, is described. The reaction is proposed to go via a carbocation intermediate, which could be generated directly from cleavage of the sp(3) C-H bond of 1,1-diphenylketone. Subsequent α-arylation was achieved at the methene sp(3) carbon atom of the substituted ketone. A variety of substituted aromatic and heteroaromatic compounds were compatible with this reaction. In addition, benzopinacolones were converted into sterically hindered, tetrasubstituted alkenes and polycyclic aromatic compounds.


Assuntos
Alcenos/química , Butanonas/química , Cetonas/química , Hidrocarbonetos Policíclicos Aromáticos/química , Butanonas/síntese química , Carbono/química , Hidrogênio/química , Teoria Quântica , Estereoisomerismo
10.
Eur J Med Chem ; 69: 768-78, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24099996

RESUMO

In order to find the vitamin D receptor (VDR) ligand whose VDR agonistic activity is separated from the calcemic activity sufficiently, novel nonsecosteroidal analogs with phenyl-pyrrolyl pentane skeleton were synthesized and evaluated for the VDR binding affinity, antiproliferative activity in vitro and serum calcium raising ability in vivo (tacalcitol used as control). Among them, several compounds showed varying degrees of VDR agonistic and growth inhibition activities of the tested cell lines. The most effective compound 2g (EC50: 1.06 nM) exhibited stronger VDR agonistic activity than tacalcitol (EC50: 7.05 nM), inhibited the proliferations of HaCaT and MCF-7 cells with IC50 of 2.06 µM and 0.307 µM (tacalcitol: 2.07 µM and 0.057 µM) and showed no significant effect on serum calcium.


Assuntos
Antineoplásicos/farmacologia , Butanonas/farmacologia , Pirróis/farmacologia , Receptores de Calcitriol/agonistas , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Butanonas/síntese química , Butanonas/química , Cálcio/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Ligantes , Células MCF-7 , Camundongos , Camundongos Endogâmicos ICR , Modelos Moleculares , Estrutura Molecular , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade
11.
J Am Chem Soc ; 135(16): 6026-9, 2013 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-23586708

RESUMO

The first examples of catalytic cross-metathesis (CM) reactions that furnish Z-(pinacolato)allylboron and Z-(pinacolato)alkenylboron compounds are disclosed. Products are generated with high Z selectivity by the use of a W-based monoaryloxide pyrrolide (MAP) complex (up to 91% yield and >98:2 Z:E). The more sterically demanding Z-alkenylboron species are obtained in the presence of Mo-based MAP complexes in up to 93% yield and 97% Z selectivity. Z-selective CM with 1,3-dienes and aryl olefins are reported for the first time. The utility of the approach, in combination with catalytic cross coupling, is demonstrated by a concise and stereoselective synthesis of anticancer agent combretastatin A-4.


Assuntos
Compostos de Boro/síntese química , Butanonas/síntese química , Alcenos , Antineoplásicos Fitogênicos/química , Bibenzilas/química , Compostos de Boro/química , Butanonas/química , Catálise , Reagentes para Ligações Cruzadas , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Estereoisomerismo , Estirenos/química , Compostos de Vinila/química
12.
J Org Chem ; 77(19): 8840-4, 2012 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-22992005

RESUMO

The LHMDS-promoted in situ generation of difluoroenolates from readily available 1-aryl and 1-alkyl 2,2,4,4,4-pentafluorobutan-1,3-dione hydrates has been used to produce a series of pentafluorinated ß-hydroxy ketones in up to 95% yield. The reaction proceeds under mild conditions, tolerates a wide range of functional groups, and is complete within 10 min. Reduction toward the corresponding 1,3-diol with DIBAL gives quantitative amounts and favors the formation of the syn-isomer.


Assuntos
Butanonas/síntese química , Hidrocarbonetos Fluorados/síntese química , Cetonas/síntese química , Butanonas/química , Catálise , Hidrocarbonetos Fluorados/química , Cetonas/química , Estrutura Molecular , Estereoisomerismo
13.
Org Lett ; 14(12): 3040-3, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22626008

RESUMO

A formal [4 + 2] cycloaddition of 2,3-disubstituted indoles with vinyl methyl ketone was realized in the presence of a catalytic amount of quinine-derived primary amine and pentafluorobenzoic acid. This method provides bridged-ring indoline scaffolds containing two quaternary carbon centers with excellent yields and enantioselectivity (up to 98% yield and 98% ee).


Assuntos
Butanonas/síntese química , Indóis/síntese química , Compostos de Vinila/síntese química , Catálise , Ciclização , Indóis/química , Estrutura Molecular , Estereoisomerismo , Compostos de Vinila/química
14.
Bioorg Med Chem ; 20(6): 2119-30, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22364952

RESUMO

We wish to report the further design and improved synthesis that resulted in two series of target molecules, TM-1 and TM-2, with remarkably simplified structures containing ß-amino ketone of discrete nabumetone moiety. These were obtained via a 'one-pot, two-step, three-component' protocol of Mannich reaction with yield up to 97%. A total of 28 out of 31 new compounds were characterized using (1)H NMR, (13)C NMR, ESI MS and HRMS techniques. Studies on their antidiabetic activities, screened in vitro at 10 µg mL(-1) level, indicate that TM-2 possesses peroxisome proliferator-activated receptor activation and α-glucosidase inhibition activity significantly stronger than that of TM-1, and also that of the series B compounds that were previously synthesized by the group. Analysis of the structure-activity relationship points to the sulfanilamide unit as the most probable potent group of ß-amino ketone and, on the basis of which, a tangible strategy is presented for the development of new antidiabetic drugs.


Assuntos
Butanonas/química , Butanonas/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Cetonas/química , Cetonas/farmacologia , Aminas/síntese química , Aminas/química , Aminas/farmacologia , Butanonas/síntese química , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/metabolismo , Inibidores de Glicosídeo Hidrolases , Humanos , Hipoglicemiantes/síntese química , Cetonas/síntese química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Nabumetona , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Relação Estrutura-Atividade , Sulfanilamida , Sulfanilamidas/síntese química , Sulfanilamidas/química , Sulfanilamidas/farmacologia , alfa-Glucosidases/metabolismo
15.
J Phys Chem A ; 116(3): 1110-8, 2012 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-22242788

RESUMO

The (Z)-4,4,4-trifluoro-3-(2-hydroxyethylamino)-1-(2-hydroxyphenyl)-2-buten-1-one (C(12)H(12)F(3)NO(3)) compound was thoroughly studied by IR, Raman, UV-visible, and (13)C and (19)F NMR spectroscopies. The solid-state molecular structure was determined by X-ray diffraction methods. It crystallizes in the P2(1)/c space group with a = 12.1420(4) Å, b = 7.8210(3) Å, c = 13.8970(5) Å, ß = 116.162(2)°, and Z = 4 molecules per unit cell. The molecule shows a nearly planar molecular skeleton, favored by intramolecular OH···O and NH···O bonds, which are arranged in the lattice as an OH···O bonded polymer coiled around crystallographic 2-fold screw-axes. The three postulated tautomers were evaluated using quantum chemical calculations. The lowest energy tautomer (I) calculated with density functional theory methods agrees with the observed crystal structure. The structural and conformational properties are discussed considering the effect of the intra- and intermolecular hydrogen bond interactions.


Assuntos
Aminas/química , Butanonas/química , Etilaminas/química , Butanonas/síntese química , Cristalografia por Raios X , Etilaminas/síntese química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Teoria Quântica , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Análise Espectral Raman , Estereoisomerismo
16.
Yao Xue Xue Bao ; 46(4): 412-21, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21751495

RESUMO

Twenty five new beta-aminoalcohols containing nabumetone moiety were prepared via the reduction of potassium borohydride with a convenient and efficient procedure, starting from beta-aminoketones that have been synthesized by our group. Their chemical structures were determined by IR, MS, 1H NMR, 13C NMR, HR-MS and antidiabetic activities were screened in vitro. Preliminary results revealed that the antidiabetic activity of most beta-aminoalcohols were better than that of the corresponding beta-aminoketones. Although most compounds showed weak antidiabetic activity, the alpha-glucosidase inhibitory activity of compounds 5hd(1) and 5id(2) reached 74.37% and 90.15%, respectively, which were superior to the positive control. The relative peroxisome proliferator-activated receptor response element (PPRE) activity of five compounds were more than 60%, among them compound 5ca possessed the highest activity (112.59%). As lead molecules of antidiabetic agents, compounds 5hd(1), 5id(2) and 5ca deserve further study.


Assuntos
Amino Álcoois/síntese química , Butanonas/síntese química , Hipoglicemiantes/síntese química , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , alfa-Glucosidases/metabolismo , Amino Álcoois/química , Amino Álcoois/farmacologia , Butanonas/química , Butanonas/farmacologia , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Glicosídeo Hidrolases , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Nabumetona , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Elementos de Resposta
17.
J Org Chem ; 76(6): 1662-72, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21344895

RESUMO

New conditions for the conversion of simple tertiary amides to α-chloroenamines and their use in Zn(II)-catalyzed cycloaddition reactions with commercial α,ß-unsaturated carbonyl compounds allows rapid, regiocontrolled access to 3-acyl cyclobutanones. Reactions take place at ambient temperature without solvent, giving strained [2 + 2] adducts with all-carbon-substituted quaternary carbon atoms. Ab initio calculations of the putative keteniminium intermediate and studies with styrenyl olefins suggest a dual role for Zn(OTf)(2) during catalysis.


Assuntos
Alcenos/química , Aminas/química , Butanonas/química , Butanonas/síntese química , Elétrons , Zinco/química , Catálise , Transporte de Elétrons , Modelos Moleculares , Conformação Molecular , Teoria Quântica
18.
Environ Sci Technol ; 45(3): 923-9, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21175163

RESUMO

Formation yields of methacrolein (MAC), methyl vinyl ketone (MVK), and 3-methyl furan (3MF) from the hydroxyl radical (OH) initiated oxidation of isoprene were investigated under NO(x)-free conditions (NO(x) = NO + NO(2)) at 50 °C and 1 atm in a quartz reaction chamber coupled to a mass spectrometer. Yields of the primary products were measured at various OH and hydroperoxy (HO(2)) radical concentrations and were found to decrease as the HO(2)-to-isoprene-based peroxy radical (ISORO(2)) concentration ratio increases. This is likely the result of a competition between ISORO(2) self- and cross-reactions that lead to the formation of the primary products, with reactions between these peroxy radicals and HO(2) which can lead to the formation of peroxides. Under conditions with HO(2)/ISORO(2) ratios close to 0.1, yields of MVK (15.5% ± 1.4%) and MAC (13.0% ± 1.2%) were higher than the yields of MVK (8.9% ± 0.9%) and MAC (10.9% ± 1.1%) measured under conditions with HO(2)/ISORO(2) ratios close to 1. This radical dependence of the yields was reproduced reasonably well by an explicit model of isoprene oxidation, suggesting that the model is able to reproduce the observed products yields under a realistic range of atmospheric HO(2)/ISORO(2) ratios.


Assuntos
Acroleína/análogos & derivados , Poluentes Atmosféricos/química , Butadienos/química , Butanonas/síntese química , Hemiterpenos/química , Pentanos/química , Acroleína/análise , Acroleína/síntese química , Poluentes Atmosféricos/análise , Atmosfera/química , Butadienos/análise , Butanonas/análise , Hemiterpenos/análise , Hidróxidos/química , Óxidos de Nitrogênio/química , Oxirredução , Pentanos/análise
19.
Eur J Med Chem ; 45(12): 5998-6004, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20980079

RESUMO

Our continuing effort of searching bioactive substances from the Formosan soft coral Cladiella australis has led to the isolation of a bioactive substance austrasulfone (1), which possesses significant neuroprotective activities. A straightforward synthesis of 1 was achieved by a two-step reaction sequence. Dihydroaustrasulfone alcohol (3), the synthetic precursor of 1, not only exhibited in vitro anti-inflammatory activity, but also showed potent therapeutic ability in the treatment of neuropathic pain, atherosclerosis, and multiple sclerosis in rats.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aterosclerose/tratamento farmacológico , Butanonas/farmacologia , Esclerose Múltipla/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Dor/tratamento farmacológico , Sulfonas/farmacologia , Animais , Antozoários , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Butanonas/síntese química , Butanonas/química , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Masculino , Camundongos , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Medição da Dor , Ratos , Ratos Endogâmicos Lew , Ratos Wistar , Sulfonas/síntese química , Sulfonas/química
20.
J Hazard Mater ; 181(1-3): 1024-30, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20554382

RESUMO

Methyl ethyl ketone peroxide (MEKPO) is widely used in polymer industry. It is highly sensitive to heat, friction, shock, flame or other sources of ignition, causing risks in production, storage and transportation. In this article, MEKPO is synthesized at a high throughput with concentrated hydrogen peroxide in a microreactor for on-site and on-demand production. The influences of acid concentration, residence time, feeding rate and ratio, and reaction temperature on the yield and the mass fractions of residual methyl ethyl ketone (MEK) and active oxygen of the product are systematically investigated. Under optimized condition, the reaction is completed in a few seconds, and the product contains less than 2 wt% residual MEK and has a mass active oxygen fraction higher than 22 wt%, which meets the standard for industrial application.


Assuntos
Butanonas/síntese química , Peróxido de Hidrogênio/química , Oxigênio/química , Polímeros
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