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1.
JEMS ; 40(9): 44-7, 52, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26554181

RESUMO

High-potency marijuana wax smoked via dabbing is a newly encountered phenomenon with relevance to prehospital care providers and emergency physicians.The extract is only recently described in current peer-reviewed literature. The drug may produce paranoia and psychosis and mimic psychiatric problems. The synthetic process for this drug poses a risk for both fire and explosions creating burns and blast injuries. These four cases were encountered in a single ED in Los Angeles in a three-week period, suggesting this could be the tip of an emerging public health problem. All four of these patients were complex cases requiring advanced imaging and ICU care. Emergency personnel need to appreciate this new trend and the implications for pre-hospital care, disposition and ED treatment of these patients.


Assuntos
Traumatismos por Explosões/terapia , Butanos/síntese química , Cannabis , Cuidados Críticos/métodos , Adulto , Traumatismos por Explosões/fisiopatologia , Serviços Médicos de Emergência , Humanos , Masculino , Adulto Jovem
2.
J Org Chem ; 79(23): 11661-73, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25371047

RESUMO

The aim of this work was the synthesis of polyaromatic systems by cyclization of ß-polycarbonyls. Useful synthons for ß-polycarbonyl derivatives are branched 1,4-dienes generated by cobalt-catalyzed hydrovinylation of terminal alkenes and 2,3-dimethyl-1,3-butadiene. Thus, a series of tri-, tetra-, and pentacarbonyl synthons was successfully synthesized. Subsequently, these synthons were examined in an ozonolysis/cyclization reaction sequence. Polyaromatic derivatives were obtained in good yields and the method was applied in the synthesis of the natural product Kwanzoquinone A.


Assuntos
Aldeídos/química , Alcenos/química , Alcenos/síntese química , Antraquinonas/síntese química , Butanos/química , Butanos/síntese química , Cobalto/química , Polienos/química , Antraquinonas/química , Catálise , Ciclização , Estrutura Molecular
3.
Biotechnol Lett ; 34(4): 709-15, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22187074

RESUMO

(2R)-2-[4-(4-Cyano-2-fluorophenoxy)phenoxy]butylpropanoate (cyhalofop-butyl, CyB) was synthesized by a chemoenzymatic route involving enantioselective transesterification with Candida antarctica lipase B (Novozym 435). The optimum organic solvent, acyl donor, a ( w ), reaction temperature and shaking rate for the transesterification were acetonitrile, n-butanol, 0.11, 45°C and 200 rpm, respectively. Under the optimum conditions, the maximum substrate conversion and the enantiomeric purity of the product were 96.9 and >99%, respectively. The total yield and enantiomeric purity of CyB by this chemoenzymatic synthesis were 60.4 and >99%, respectively; 15.3 and 21% higher than that of the traditional way (45 and 78%).


Assuntos
Butanos/síntese química , Butanos/metabolismo , Lipase/metabolismo , Nitrilas/síntese química , Nitrilas/metabolismo , Acetonitrilas/metabolismo , Biotecnologia/métodos , Butanóis/metabolismo , Candida/enzimologia , Enzimas Imobilizadas/metabolismo , Esterificação , Proteínas Fúngicas , Temperatura
4.
J Am Chem Soc ; 132(5): 1450-1, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-20078044

RESUMO

Here we report the design of a new external electric field-controlled release system using functional dipolar molecules as nanoimpellers. The dipolar molecule 4-(3-cyanophenyl)butylene, which can reorient in response to external electric fields with different frequencies because of its strong inherent dipole moment, was synthesized and grafted onto the inner surfaces of mesopores. Under an alternating electric field, the swinging flexible molecular chains consequently push guest molecules out of the pore voids. This innovative approach to controlled release may provide important application opportunities in tumor treatment with a number of advantages in terms of local release with targetability, external remote control, and the nonelectrochemical nature of the process.


Assuntos
Analgésicos não Narcóticos/administração & dosagem , Butanos/química , Sistemas de Liberação de Medicamentos/métodos , Ibuprofeno/administração & dosagem , Nitrilas/química , Dióxido de Silício/química , Butanos/síntese química , Sistemas de Liberação de Medicamentos/instrumentação , Campos Eletromagnéticos , Estrutura Molecular , Nitrilas/síntese química , Porosidade
5.
Org Biomol Chem ; 8(7): 1588-95, 2010 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-20237669

RESUMO

The continuous flow synthesis of butane-2,3-diacetal protected derivatives has been achieved using commercially available flow chemistry microreactors in concert with solid supported reagents and scavengers to provide in-line purification systems. The BDA protected products are all obtained in superior yield to the corresponding batch processes.


Assuntos
Acetais/síntese química , Butanos/síntese química , Microquímica/instrumentação , Acetais/química , Butanos/química , Desenho de Equipamento , Microquímica/métodos
6.
Yakugaku Zasshi ; 130(10): 1339-46, 2010 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-20930486

RESUMO

1-Azabicyclo [1.1.0] butane (ABB) bearing the highly strained bicyclic structure, which is synthetically useful for the preparation of 3-substituted azetidines, was obtained by the cyclization of 2,3-dibromopropylamine hydrobromide derived from inexpensive allylamine only with organolithium compounds and lithium amides. When other bases were employed, such as potassium, sodium, and magnesium species, the reaction yielded almost no ABB. It was speculated that a lithium cation played an important role in the cyclization. Thus, we proposed that this reaction proceeded by the consecutive cyclization to aziridines via the SN2 process involving the activation of the C-Br bond based on the intermolecular Br…Li(+) coordination, as a result of studies of reaction mechanisms.


Assuntos
Compostos Azabicíclicos/síntese química , Butanos/síntese química , Amidas , Aziridinas , Ciclização , Compostos de Lítio , Propilaminas
7.
Curr Top Med Chem ; 20(9): 720-730, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32066360

RESUMO

AIMS: Computational modelling may help us to detect the more important factors governing this process in order to optimize it. BACKGROUND: The generation of hazardous organic waste in teaching and research laboratories poses a big problem that universities have to manage. METHODS: In this work, we report on the experimental measurement of waste generation on the chemical education laboratories within our department. We measured the waste generated in the teaching laboratories of the Organic Chemistry Department II (UPV/EHU), in the second semester of the 2017/2018 academic year. Likewise, to know the anthropogenic and social factors related to the generation of waste, a questionnaire has been utilized. We focused on all students of Experimentation in Organic Chemistry (EOC) and Organic Chemistry II (OC2) subjects. It helped us to know their prior knowledge about waste, awareness of the problem of separate organic waste and the correct use of the containers. These results, together with the volumetric data, have been analyzed with statistical analysis software. We obtained two Perturbation-Theory Machine Learning (PTML) models including chemical, operational, and academic factors. The dataset analyzed included 6050 cases of laboratory practices vs. practices of reference. RESULTS: These models predict the values of acetone waste with R2 = 0.88 and non-halogenated waste with R2 = 0.91. CONCLUSION: This work opens a new gate to the implementation of more sustainable techniques and a circular economy with the aim of improving the quality of university education processes.


Assuntos
Química Orgânica , Química Farmacêutica , Poluentes Ambientais/química , Laboratórios , Acetanilidas/síntese química , Butanos/síntese química , Simulação por Computador , Humanos , Aprendizagem , Aprendizado de Máquina , Modelos Estatísticos , Pentanóis/síntese química , Software , Estudantes , Ensino , Universidades
8.
Eur J Med Chem ; 186: 111910, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31801655

RESUMO

Drug efflux pumps confer multidrug resistance to dangerous bacterial pathogens which makes these proteins promising drug targets. Herein, we present initial chemical optimization and structure-activity relationship (SAR) data around a previously described efflux pump inhibitor, nordihydroguaretic acid (NDGA). Four series of novel NDGA analogues that target Escherichia coli AcrB were designed, synthesized and evaluated for their ability to potentiate the activity of antibiotics, to inhibit AcrB-mediated substrate efflux and reduce off-target activity. Nine novel structures were identified that increased the efficacy of a panel of antibiotics, inhibited drug efflux and reduced permeabilization of the bacterial outer and inner membranes. Among them, WA7, WB11 and WD6 possessing broad-spectrum antimicrobial sensitization activity were identified as NDGA analogues with favorable properties as potential AcrB inhibitors, demonstrating moderate improvement in potency as compared to NDGA. In particular, WD6 was the most broadly active analogue improving the activity of all four classes of antibacterials tested.


Assuntos
Anti-Infecciosos/farmacologia , Compostos de Benzil/farmacologia , Produtos Biológicos/farmacologia , Butanos/farmacologia , Descoberta de Drogas , Proteínas de Escherichia coli/antagonistas & inibidores , Escherichia coli/efeitos dos fármacos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Compostos de Benzil/síntese química , Compostos de Benzil/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Butanos/síntese química , Butanos/química , Relação Dose-Resposta a Droga , Técnicas Eletroquímicas , Proteínas de Escherichia coli/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Relação Estrutura-Atividade
9.
Chemistry ; 15(19): 4925-30, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19301341

RESUMO

In the conjugate addition reaction of a alpha,beta-unsaturated compound, the new stereogenic center is created in the beta-position. In contrast, conjugate addition to 1,4-dicarbonyl but-2-enes will generate an alpha-stereogenic center with respect to one of the carbonyl groups, which informally, can be considered as an inversion of normal reactivity patterns or Umpolung. In this paper, we demonstrate that chiral bicyclic guanidine can catalyze the addition of 1,3-dicarbonyl compounds to 1,4-dicarbonyl but-2-enes [(E)-4-oxo-4-arylbutenamides and (E)-4-oxo-4-arylbutenones] with high regioselectivity and enantioselectivity (ee values up to 97%).


Assuntos
Alcenos/síntese química , Amidas/síntese química , Butanos/síntese química , Guanidina/química , Cetonas/síntese química , Alcenos/química , Amidas/química , Butanos/química , Catálise , Cetonas/química , Estereoisomerismo
10.
J Org Chem ; 74(9): 3606-8, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19351149

RESUMO

The one-pot preparation of N-sulfinylamine diastereomers proceeds in excellent yields (84-98%) for a diverse set of N-sulfinyl imine addition products. The method is operationally simple and extractive isolation provides analytically pure mixtures of diastereomers as standards for the rapid and accurate determination of N-sulfinylamine diastereomeric purity.


Assuntos
Aminas/síntese química , Butanos/síntese química , Compostos de Sulfônio/síntese química , Aminas/química , Butanos/química , Estereoisomerismo , Especificidade por Substrato , Compostos de Sulfônio/química
11.
J Org Chem ; 74(19): 7544-7, 2009 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-19715283

RESUMO

Isobenzofurans (IBF)s have seen widespread use in the synthesis of both natural products and polycyclic aromatic hydrocarbons. There are few examples that have two IBF entities linked in a fused aromatic ring system. Here we present the synthesis and characterization of a bis(IBF), 2,7-di(tert-butyl)pyreno[4,5-c:9,10-c']difuran. Reaction with bis(maleimide) dienophiles gives pyrenophanes. The solid-state structures of the bis(IBF) and two cyclophanes are discussed.


Assuntos
Benzofuranos/química , Benzofuranos/síntese química , Butanos/química , Butanos/síntese química , Furanos/química , Furanos/síntese química , Compostos Policíclicos/química , Compostos Policíclicos/síntese química , Estrutura Molecular , Estereoisomerismo
14.
J Hazard Mater ; 150(2): 285-9, 2008 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-17544579

RESUMO

Separation with solvent extraction of Cu(II), Co(II) and Ni(II) from aqueous solution using N,N'-bis-(salicylaldehydene)-1,4-bis-(p-aminophenoxy)butane (H(2)L) as the new extractant has been studied. The new Schiff base, was synthesized by reaction of 1,4-bis-(p-aminophenoxy)butane and salicylaldehyde. Microanalytical data, elemental analysis, UV-vis (1)H NMR and (13)C NMR spectra and IR-spectra were used to confirm the structures. The extractability and selectivity of divalent cations was evaluated as a function of relationship between distribution ratios of the metal and pH or ligand concentration. Cu(+2) showed the highest extractability and selectivity at pH 7.8, whereas Ni(+2) and Co(+2) showed at pH 9.2. From the loaded organic phase, Cu(II), Co(II), Ni(II) stripping were carried out in one stage with aqueous acid solution including various concentrations of HCl. The stripping efficiency was found to be quantitative in case of 1.5M HCl. From quantitative evaluation of the extraction equilibrium data, it has been deduced that the complexes extracted are the simple 1:1 chelates, CuL, CoL, NiL.


Assuntos
Butanos/síntese química , Metais Pesados/química , Solventes/química , Cátions Bivalentes/química , Cobalto/química , Cobre/química , Concentração de Íons de Hidrogênio , Ligantes , Níquel/química , Compostos Orgânicos/química , Espectrofotometria , Água/química
15.
Eur J Med Chem ; 158: 534-547, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30243155

RESUMO

[M(sac)2(dppp)] (1 and 2), [M(dppp)2](sac)2 (3 and 4) and [M(sac)2(dppb)] (5 and 6) complexes, where M = PdII (1, 3 and 5) and PtII (2, 4 and 6), sac = saccharinate, dppp = 1,3-bis(diphenylphosphino)propane and dppb = 1,4-bis(diphenylphosphino)butane, were synthesized and characterized by IR, NMR, ESI-MS and X-ray diffraction. The anticancer activity of the complexes against human lung (A549), breast (MCF-7), prostate (DU145) and colon (HCT116) cancer cell lines showed that the cationic complexes of dppp (3 and 4) and neutral Pt complex of dppb (6) were the most active agents of series. 3 and 4 exhibited antiproliferative activity, while 6 was highly cytotoxic compared to cisplatin. These complexes were therefore subjected to further investigations to ascertain the possible role of lipophilicity, cellular uptake and DNA/HSA binding in their biological activity. Flow cytometry analysis revealed that complex 6 induced apoptotic cell death in A549 and HCT116 cells and caused the cell cycle arrest at the S phase and overproduction of reactive oxygen species (ROS), giving rise to mitochondrial depolarization and DNA damage.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Compostos Organoplatínicos/química , Compostos Organoplatínicos/farmacologia , Paládio/química , Paládio/farmacologia , Células A549 , Antineoplásicos/síntese química , Butanos/síntese química , Butanos/química , Butanos/farmacologia , Linhagem Celular Tumoral , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Células HCT116 , Humanos , Neoplasias/tratamento farmacológico , Compostos Organoplatínicos/síntese química , Fosfinas/síntese química , Fosfinas/química , Fosfinas/farmacologia , Propano/síntese química , Propano/química , Propano/farmacologia
16.
Eur J Med Chem ; 146: 381-394, 2018 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-29407965

RESUMO

A novel butanehydrazide derivatives of purine-2,6-dione designed using a ligand-based approach were synthesized and their in vitro activity against both PDE4B and PDE7A isoenzymes was assessed. The 7,8-disubstituted purine-2,6-dione derivatives 31, 34, 37, and 40 appeared to be the most potent PDE4/7 inhibitors with IC50 values in the range of that of the reference rolipram and BRL-50481, respectively. Moreover, docking studies explained the importance of N-(2,3,4-trihydroxybenzylidene)butanehydrazide substituent in position 7 of purine-2,6-dione core for dual PDE4/7 inhibitory properties. The inhibition of both the cAMP-specific PDE isoenzymes resulted in a strong anti-TNF-α effect. Compounds 31, 34, and 37 in the in vivo study in rats with LPS-induced endotoxemia decreased the maximum concentration of this proinflammatory cytokine by 53, 84 and 88%, respectively.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Butanos/farmacologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 7/antagonistas & inibidores , Desenho de Fármacos , Hidrazinas/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Purinonas/farmacologia , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Butanos/análise , Butanos/síntese química , Butanos/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 7/metabolismo , Relação Dose-Resposta a Droga , Endotoxemia/tratamento farmacológico , Humanos , Hidrazinas/síntese química , Hidrazinas/química , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Masculino , Estrutura Molecular , Inibidores de Fosfodiesterase/síntese química , Inibidores de Fosfodiesterase/química , Purinonas/síntese química , Purinonas/química , Ratos , Ratos Wistar , Relação Estrutura-Atividade
17.
J Phys Chem B ; 111(14): 3571-5, 2007 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-17388523

RESUMO

The appearance of the gamma phase of a polypropylene-containing terpolymer prepared with a Ziegler-Natta catalyst was analyzed, and a novel strategy to make a polypropylene terpolymer which contains a high content of the gamma phase was experimentally sought. Wide-angle X-ray scattering and differential scanning calorimetry measurements have been conducted to investigate gamma-phase formation. Using a mixed flow of both elongational and shear components (a foaming process), we could introduce a lot of nuclei in the melt by flow-induced crystallization (FIC). The large number of nuclei accounting for the structural disorder during crystallite formation was ascribed to be the reason for gamma-phase formation in the terpolymer crystallization. A uniform distribution of defects in the melt crystallization was the key to obtaining a high content of the gamma phase.


Assuntos
Butanos/química , Polipropilenos/química , Butanos/síntese química , Varredura Diferencial de Calorimetria , Catálise , Cristalização , Peso Molecular , Polipropilenos/síntese química , Temperatura , Fatores de Tempo , Difração de Raios X
19.
Ann Chim ; 97(5-6): 287-94, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17696007

RESUMO

The extraction of copper(II), nickel(II) and cobalt(II) from the aqueous phase with N,N'-bis(salicylaldehydene)-1,4-bis-(m-aminophenoxy)butane (MAS), which was synthesized from 1,4-bis(m-aminophenoxy)butane and salicylaldehyde, was studied. Microanalytical data, elemental analysis, UV-visible 1H and 13C n.m.r. spectra and IR-spectra were used to confirm the structures. The extractability and selectivity of divalent cations were evaluated as a function of relationship between distribution ratio of the metal and pH or ligand concentration. Cu+2 showed the highest extractability and selectivity at pH 6.0, whereas Ni+2 and Co+2 showed at pH 9.2. The stoichiometries of the compounds formed were estimated to be CuL, CoL, NiL, where L is N,N'-bis(salicylaldehydene)-1,4-bis-(m-aminophenoxy)butane. It was concluded that MAS can effectively be used in solvent extraction of copper(II), nickel(II) and cobalt(II) from the aqeous phase to the organic phase.


Assuntos
Butanos/síntese química , Metais Pesados/química , Solventes/química , Cátions Bivalentes/química , Cobalto/química , Cobre/química , Concentração de Íons de Hidrogênio , Ligantes , Níquel/química , Compostos Orgânicos/química , Espectrofotometria , Água/química
20.
Eur J Med Chem ; 126: 133-142, 2017 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-27750147

RESUMO

Twenty-eight new 12N-benzenesulfonyl matrinic butane and halogenated 12N-sulfonyl matrinic butane/ethane derivatives were designed, synthesized and evaluated for their anti-coxsakievirus activities against CVB3 taking compound 1 as the lead. SAR analysis indicated the introduction of a fluoro atom on the 1'-position might be helpful for keeping potency. Among them, compound 8a exhibited potential activities against all CVBs with IC50 ranging from 0.69 to 5.14 µM, suggesting a broad-spectrum anti-coxsackievirus B feature. In addition, it also displayed an excellent PK and a good safety profile, indicating a highly druggable nature. Thus, we consider compound 8a to be a promising drug candidate in the treatment of not only viral myocarditis caused by CVB3 but also various diseases infected with coxsackieviruses B.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Butanos/síntese química , Butanos/farmacologia , Enterovirus Humano B/efeitos dos fármacos , Halogenação , Animais , Antivirais/química , Antivirais/toxicidade , Butanos/química , Butanos/toxicidade , Técnicas de Química Sintética , Chlorocebus aethiops , Desenho de Fármacos , Relação Estrutura-Atividade , Células Vero
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