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1.
Molecules ; 26(5)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673560

RESUMO

BACKGROUND: Khella (Ammi visnaga Lam.) fruits (Apiaceae) are rich in furanochromones, mainly khellin and visnagin, and are thus incorporated in several pharmaceutical products used mainly for treatment of renal stones. METHODS: The objective of this study was to compare the yield of khellin and visnagin obtained using different conventional solvents and supercritical fluid extraction (SCFE) with carbon dioxide (containing 5% methanol as co-solvent). Water, acetone and ethanol (30% and 95%) were selected as conventional solvents. RESULTS: Highest extract yield was obtained from 30% ethanol (15.44%), while SCFE gave the lowest yield (4.50%). However, the percentage of furanochromones were highest in SCFE (30.1%), and lowest in boiling water extract (5.95%). HPLC analysis of conventional solvent extracts showed other coumarins that did not appear in supercritical fluid extraction chromatogram due to non-selectivity of solvent extraction. Ammi visnaga extracts as well as standard khellin and visnagin were tested for their cytotoxic activity using sulforhodamine B assay on breast cancer (MCF-7) and hepatocellular carcinoma (Hep G2) cell lines. Results revealed a strong cytotoxic activity (IC50 < 20 µg/mL) for the SCFE and standard compounds (khellin and visnagin) (IC50 ranging between 12.54 ± 0.57 and 17.53 ± 1.03 µg/mL). However, ethanol and acetone extracts had moderate cytotoxic activity (IC50 20-90 µg/mL) and aqueous extract had a weak activity (IC50 > 90 µg/mL). CONCLUSIONS: Thus, supercritical fluid extraction is an efficient, relatively safe, and cheap technique that yielded a more selective purified extract with better cytotoxic activity.


Assuntos
Ammi/química , Cromatografia com Fluido Supercrítico/métodos , Cromonas/química , Furanos/química , Extratos Vegetais/química , Dióxido de Carbono/química , Cromonas/farmacologia , Cumarínicos/química , Etanol/química , Furanos/farmacologia , Células Hep G2 , Humanos , Quelina/farmacologia , Quelina/normas , Células MCF-7 , Metanol/química , Extratos Vegetais/farmacologia , Solventes/química
2.
Eur J Med Chem ; 216: 113322, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33652353

RESUMO

In this paper, the 2,5-disubstituted furan derivatives containing 1,3,4-thiadiazole were synthesized and screened for their inhibitory activity against α-glucosidase and ß-glucuronidases to obtain potent α-glucosidase inhibitor 9 (IC50 = 0.186 µM) and E. coli ß-glucuronidase inhibitor 26 (IC50 = 0.082 µM), respectively. The mechanisms of the compounds were studied. The kinetic study revealed that compound 9 is a competitive inhibitor against α-glucosidase (Ki = 0.05 ± 0.003 µM) and molecular docking simulation showed several key interactions between 9 and the target including hydrogen bond and p-π stacking interaction. Derivative 26 (Ki = 0.06 ± 0.005 µM) displayed uncompetitive inhibition behavior against EcGUS. Furthermore, the result of docking revealed the furan ring of 26 may be a key moiety in obstructing the active domain of EcGUS. In addition, compound 15 exhibited significant inhibitory activity against these two enzymes, with potential therapeutic effects against diabetes and against CPT-11-induced diarrhea. At the same time, their low toxicity against normal liver tissue LO2 cells lays the foundation for in vivo studies and the development of bifunctional drug.


Assuntos
Escherichia coli/enzimologia , Furanos/química , Glicoproteínas/química , Inibidores de Glicosídeo Hidrolases/química , Tiadiazóis/química , Sítios de Ligação , Domínio Catalítico , Linhagem Celular , Sobrevivência Celular , Proteínas de Escherichia coli/antagonistas & inibidores , Proteínas de Escherichia coli/metabolismo , Furanos/farmacologia , Glucuronidase/antagonistas & inibidores , Glucuronidase/metabolismo , Glicoproteínas/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Cinética , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
3.
Molecules ; 26(4)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671782

RESUMO

CrCl3(thf)3 is a common starting material in the synthesis of organometallic and coordination compounds of Cr. Deposited as an irregular solid with no possibility of recrystallization, it is not a purity guaranteed chemical, causing problems in some cases. In this work, we disclose a well-defined form of the THF adduct of CrCl3 ([CrCl2(µ-Cl)(thf)2]2), a crystalline solid, that enables structure determination by X-ray crystallography. The EA data and XRD pattern of the bulk agreed with the revealed structure. Moreover, its preparation procedure is facile: evacuation of CrCl3·6H2O at 100 °C, treatment with 6 equivalents of Me3SiCl in a minimal amount of THF, and crystallization from CH2Cl2. The ethylene tetramerization catalyst [iPrN{P(C6H4-p-Si(nBu)3)2}2CrCl2]+[B(C6F5)4]- prepared using well-defined [CrCl2(µ-Cl)(thf)2]2 as a starting material exhibited a reliably high activity (6600 kg/g-Cr/h; 1-octene selectivity at 40 °C, 75%), while that of the one prepared using the impure CrCl3(thf)3 was inconsistent and relatively low (~3000 kg/g-Cr/h). By using well-defined [CrCl2(µ-Cl)(thf)2]2 as a Cr source, single crystals of [(CH3CN)4CrCl2]+[B(C6F5)4]- and [{Et(Cl)Al(N(iPr)2)2}Cr(µ-Cl)]2 were obtained, allowing structure determination by X-ray crystallography, which had been unsuccessful when the previously known CrCl3(thf)3 was used as the Cr source.


Assuntos
Cromo/química , Complexos de Coordenação/química , Furanos/química , Complexos de Coordenação/síntese química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular
4.
Exp Parasitol ; 224: 108100, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33744229

RESUMO

Chagas disease and leishmaniasis are neglected diseases caused by parasites of the Trypanosomatidae family and together they affect millions of people in the five continents. The treatment of Chagas disease is based on benznidazole, whereas for leishmaniasis few drugs are available, such as amphotericin B and miltefosine. In both cases, the current treatment is not entirely efficient due to toxicity or side effects. Encouraged by the need to discover valid targets and new treatment options, we evaluated 8 furan compounds against Trypanosoma cruzi and Leishmania amazonensis, considering their effects against proliferation, infection, and ultrastructure. Many of them were able to impair T. cruzi and L. amazonensis proliferation, as well as cause ultrastructural alterations, such as Golgi apparatus disorganization, autophagosome formation, and mitochondrial swelling. Taken together, the results obtained so far make these compounds eligible for further steps of chemotherapy study.


Assuntos
Furanos/farmacologia , Leishmania mexicana/efeitos dos fármacos , Trypanosoma cruzi/efeitos dos fármacos , Linhagem Celular , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Cromatografia em Camada Delgada , Doenças Endêmicas , Furanos/química , Humanos , Concentração Inibidora 50 , Leishmania mexicana/crescimento & desenvolvimento , Leishmania mexicana/ultraestrutura , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Macrófagos , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Simulação de Acoplamento Molecular , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/parasitologia , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma cruzi/ultraestrutura
5.
Eur J Med Chem ; 216: 113336, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33725657

RESUMO

P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) is a phenomenon in which cells become resistant to structurally and mechanistically unrelated drugs resulting in low intracellular drug concentrations. It is one of the noteworthy problems in malignant tumor clinical therapeutics. So P-gp protein is one of the ideal targets to solve MDR. Based on the lead compound 5m obtained from our previous work, a series of furan derivatives featuring alkyl-substituted phenols and 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline were designed and synthesized as reversal agents against P-gp in this paper. Compound 16 containing isopropoxy possessed good potency against P-gp mediated MDR in MCF-7/ADR (IC50 (doxorubicin) = 0.73 µM, RF = 69.6 with 5 µM 16 treated). Western blot results and Rh123 accumulation assays showed that 16 effectively inhibited P-gp efflux function but not its expression. The preliminary structure-activity relationship and docking studies demonstrated that compound 16 would be a potential P-gp inhibitor. Most worthy of mention is that compound 16 has achieved satisfactory results in combination with a variety of anti-tumor drugs, such as doxorubicin, paclitaxel, and vincristine. This study forwards a hopeful P-gp inhibitor for withstanding malignant tumor cell with multidrug resistance setting the basis for further studies.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/farmacologia , Desenho de Fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Furanos/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/farmacologia , Furanos/metabolismo , Furanos/farmacologia , Humanos , Simulação de Acoplamento Molecular , Paclitaxel/farmacologia , Relação Estrutura-Atividade , Tetra-Hidroisoquinolinas/química , Tetra-Hidroisoquinolinas/metabolismo , Tetra-Hidroisoquinolinas/farmacologia
6.
Nat Commun ; 12(1): 1868, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767166

RESUMO

It is very attractive yet underexplored to synthesize heterocyclic moieties pertaining to biologically active molecules from biomass-based starting compounds. Herein, we report an electrocatalytic Achmatowicz reaction for the synthesis of hydropyranones from furfuryl alcohols, which can be readily produced from biomass-derived and industrially available furfural. Taking advantage of photo-induced polymerization of a bipyridyl ligand, we demonstrate the facile preparation of a heterogenized nickel electrocatalyst, which effectively drives the Achmatowicz reaction electrochemically. A suite of characterization techniques and density functional theory computations were performed to aid the understanding of the reaction mechanism. It is rationalized that the unsaturated coordination sphere of nickel sites in our electrocatalyst plays an important role at low applied potential, not only allowing the intimate interaction between the nickel center and furfuryl alcohol but also enabling the transfer of hydroxide from nickel to the bound furfuryl alcohol.


Assuntos
Técnicas Eletroquímicas/métodos , Furanos/química , 2,2'-Dipiridil/química , Biomassa , Catálise , Níquel/química
7.
Molecules ; 26(4)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562414

RESUMO

Major lignans of sesame sesamin and sesamolin are benzodioxol--substituted furofurans. Sesamol, sesaminol, its epimers, and episesamin are transformation products found in processed products. Synthetic routes to all lignans are known but only sesamol is synthesized industrially. Biosynthesis of furofuran lignans begins with the dimerization of coniferyl alcohol, followed by the formation of dioxoles, oxidation, and glycosylation. Most genes of the lignan pathway in sesame have been identified but the inheritance of lignan content is poorly understood. Health-promoting properties make lignans attractive components of functional food. Lignans enhance the efficiency of insecticides and possess antifeedant activity, but their biological function in plants remains hypothetical. In this work, extensive literature including historical texts is reviewed, controversial issues are critically examined, and errors perpetuated in literature are corrected. The following aspects are covered: chemical properties and transformations of lignans; analysis, purification, and total synthesis; occurrence in Seseamum indicum and related plants; biosynthesis and genetics; biological activities; health-promoting properties; and biological functions. Finally, the improvement of lignan content in sesame seeds by breeding and biotechnology and the potential of hairy roots for manufacturing lignans in vitro are outlined.


Assuntos
Benzodioxóis/química , Furanos/química , Lignanas/química , Fenóis/química , Sesamum/química , Benzodioxóis/síntese química , Dioxóis/química , Lignanas/síntese química , Oxirredução , Fenóis/síntese química , Sementes/química , Sesamum/genética
8.
Nature ; 590(7846): 463-467, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33536618

RESUMO

Actinobacteria produce numerous antibiotics and other specialized metabolites that have important applications in medicine and agriculture1. Diffusible hormones frequently control the production of such metabolites by binding TetR family transcriptional repressors (TFTRs), but the molecular basis for this remains unclear2. The production of methylenomycin antibiotics in Streptomyces coelicolor A3(2) is initiated by the binding of 2-alkyl-4-hydroxymethylfuran-3-carboxylic acid (AHFCA) hormones to the TFTR MmfR3. Here we report the X-ray crystal structure of an MmfR-AHFCA complex, establishing the structural basis for hormone recognition. We also elucidate the mechanism for DNA release upon hormone binding through the single-particle cryo-electron microscopy structure of an MmfR-operator complex. DNA binding and release assays with MmfR mutants and synthetic AHFCA analogues define the role of individual amino acid residues and hormone functional groups in ligand recognition and DNA release. These findings will facilitate the exploitation of actinobacterial hormones and their associated TFTRs in synthetic biology and in the discovery of new antibiotics.


Assuntos
Antibacterianos/biossíntese , Furanos/metabolismo , Streptomyces coelicolor/metabolismo , Apoproteínas/química , Apoproteínas/metabolismo , Apoproteínas/ultraestrutura , Proteínas de Bactérias/química , Proteínas de Bactérias/classificação , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/ultraestrutura , Microscopia Crioeletrônica , Cristalografia por Raios X , DNA/química , DNA/genética , DNA/metabolismo , DNA/ultraestrutura , Furanos/química , Hormônios/química , Hormônios/classificação , Hormônios/metabolismo , Ligantes , Modelos Moleculares , Peptídeos/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/classificação , Proteínas Repressoras/metabolismo , Proteínas Repressoras/ultraestrutura , Transdução de Sinais , Streptomyces coelicolor/química , Streptomyces coelicolor/genética , Relação Estrutura-Atividade
9.
Molecules ; 26(4)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578831

RESUMO

Currently, SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) has infected people among all countries and is a pandemic as declared by the World Health Organization (WHO). SARS-CoVID-2 main protease is one of the therapeutic drug targets that has been shown to reduce virus replication, and its high-resolution 3D structures in complex with inhibitors have been solved. Previously, we had demonstrated the potential of natural compounds such as serine protease inhibitors eventually leading us to hypothesize that FDA-approved marine drugs have the potential to inhibit the biological activity of SARS-CoV-2 main protease. Initially, field-template and structure-activity atlas models were constructed to understand and explain the molecular features responsible for SARS-CoVID-2 main protease inhibitors, which revealed that Eribulin Mesylate, Plitidepsin, and Trabectedin possess similar characteristics related to SARS-CoVID-2 main protease inhibitors. Later, protein-ligand interactions are studied using ensemble molecular-docking simulations that revealed that marine drugs bind at the active site of the main protease. The three-dimensional reference interaction site model (3D-RISM) studies show that marine drugs displace water molecules at the active site, and interactions observed are favorable. These computational studies eventually paved an interest in further in vitro studies. Finally, these findings are new and indeed provide insights into the role of FDA-approved marine drugs, which are already in clinical use for cancer treatment as a potential alternative to prevent and treat infected people with SARS-CoV-2.


Assuntos
Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Inibidores de Serino Proteinase/farmacologia , Domínio Catalítico , Depsipeptídeos/química , Depsipeptídeos/farmacologia , Reposicionamento de Medicamentos , Furanos/química , Furanos/farmacologia , Humanos , Cetonas/química , Cetonas/farmacologia , Modelos Moleculares , Simulação de Acoplamento Molecular , Relação Quantitativa Estrutura-Atividade , Inibidores de Serino Proteinase/química , Trabectedina/química , Trabectedina/farmacologia , Proteínas Virais/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos
10.
Nat Chem ; 13(1): 47-55, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33353970

RESUMO

Polyether ionophores are complex natural products capable of transporting cations across biological membranes. Many polyether ionophores possess potent antimicrobial activity and a few selected compounds have the ability to target aggressive cancer cells. Nevertheless, ionophore function is believed to be associated with idiosyncratic cellular toxicity and, consequently, human clinical development has not been pursued. Here, we demonstrate that structurally novel polyether ionophores can be efficiently constructed by recycling components of highly abundant polyethers to afford analogues with enhanced antibacterial selectivity compared to a panel of natural polyether ionophores. We used classic degradation reactions of the natural polyethers lasalocid and monensin and combined the resulting fragments with building blocks provided by total synthesis, including halogen-functionalized tetronic acids as cation-binding groups. Our results suggest that structural optimization of polyether ionophores is possible and that this area represents a potential opportunity for future methodological innovation.


Assuntos
Antibacterianos/síntese química , Éteres/química , Ionóforos/química , Aldeídos/química , Antibacterianos/química , Antibacterianos/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Furanos/síntese química , Furanos/química , Humanos , Ionóforos/síntese química , Ionóforos/farmacologia , Lasalocida/síntese química , Lasalocida/química , Conformação Molecular , Monensin/síntese química , Monensin/química , Oxirredução
11.
Carbohydr Polym ; 254: 117296, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357864

RESUMO

A fully biobased benzoxazine monomer, V-fa (using vanillin and furfurylamine) was grafted onto chitosan (CS) at different weight ratios (CXVY) using "grafting to" benign Schiff base chemistry. Incorporation of V-fa onto CS increased the tensile strength and improved chemical resistance of the CS-graft-V-fa films. Reversible labile linkages, expansion of CS galleries and leaching out of phenolic species from biobased polymer films led to an improved antibacterial activity against Staphylococcus aureus, which is ∼125 times higher than the bare CS film, V-fa and oligomeric V-fa. The leached out species from films were analyzed extensively by NMR, FTIR, GPC, ABTS and HRMS analysis. Oxidative-stress seems to be responsible for antibacterial activity. Current work illustrates an attractive synthetic approach and the improved antibacterial performance of biobased CS-graft-poly(V-fa) films which may hold as a potential alternative for wound-healing and implant applications in future.


Assuntos
Antibacterianos/química , Antioxidantes/química , Benzoxazinas/química , Quitosana/química , Liberação Controlada de Fármacos , Staphylococcus aureus/efeitos dos fármacos , Benzaldeídos/química , Furanos/química , Interações Hidrofóbicas e Hidrofílicas , Viabilidade Microbiana/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Solventes/química , Staphylococcus aureus/metabolismo , Resistência à Tração , Transplante/métodos , Água/química , Cicatrização/efeitos dos fármacos
12.
Food Chem ; 338: 128068, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32950010

RESUMO

A novel and green method was developed for enrichment of maneb (manganese ethylene-bisdithiocarbamate) with a supramolecular solvent liquid phase microextraction method. The microextraction method has been used for the first time in the literature for separation-preconcentration of maneb. 1-decanol and tetrahydrofuran were used in the supramolecular solvent formation. The Mn2+ content of maneb was extracted in the supramolecular solvent phase as 1-(2-pyridylazo)-2-naphthol complex at pH 12.0. Manganese concentration was determined by UV-Vis spectrophotometer at 555 nm. Then, the maneb concentration equivalent to manganese concentration was calculated. The analytical parameters which effective in the method, including pH, volume of reagents, and sample volume were optimized. The limit of detection and the limit of quantification values for maneb were calculated as 2.22 µg L-1 and 7.32 µg L-1, respectively. The method was successfully applied in the analysis of the maneb content of water and food samples.


Assuntos
Análise de Alimentos/métodos , Maneb/análise , Espectrofotometria/métodos , Água/química , Furanos/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Microextração em Fase Líquida , Maneb/isolamento & purificação , Manganês/análise , Naftóis/química , Solventes/química
13.
Food Chem ; 337: 128008, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920267

RESUMO

This study investigated the role of furfuryl alcohol (FFA) in the formation of furfurylthiol (FFT), the most important odorant in roasted coffee, using in-bean and spiking experiments. Green beans were spiked with FFA, and after roasting FFT was quantified by stable isotope dilution analysis. The FFT level in the roasted beans increased dose-dependently with addition of FFA. Additionally, beans were spiked with isotopically labelled d2-FFA which generated isotopically labelled d2-FFT after roasting. However, no labelled furfural was observed. The results unambiguously show that FFA serves as a precursor of FFT in coffee. On the other hand, the data indicate that furfural stems not from oxidation of FFA and plays no major role as precursor for FFT formation during coffee roasting. The suggested formation pathway leads from FFA to the furfuryl cation, then protein-bound S-furfuryl-l-cysteine and by subsequent elimination to FFT.


Assuntos
Coffea/química , Furanos/química , Odorantes/análise , Compostos de Sulfidrila/química , Café , Cisteína/análise , Temperatura Alta
14.
PLoS Genet ; 16(12): e1009249, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33370251

RESUMO

Karrikins (KARs), smoke-derived butenolides, are perceived by the α/ß-fold hydrolase KARRIKIN INSENSITIVE2 (KAI2) and thought to mimic endogenous, yet elusive plant hormones tentatively called KAI2-ligands (KLs). The sensitivity to different karrikin types as well as the number of KAI2 paralogs varies among plant species, suggesting diversification and co-evolution of ligand-receptor relationships. We found that the genomes of legumes, comprising a number of important crops with protein-rich, nutritious seed, contain two or more KAI2 copies. We uncover sub-functionalization of the two KAI2 versions in the model legume Lotus japonicus and demonstrate differences in their ability to bind the synthetic ligand GR24ent-5DS in vitro and in genetic assays with Lotus japonicus and the heterologous Arabidopsis thaliana background. These differences can be explained by the exchange of a widely conserved phenylalanine in the binding pocket of KAI2a with a tryptophan in KAI2b, which arose independently in KAI2 proteins of several unrelated angiosperms. Furthermore, two polymorphic residues in the binding pocket are conserved across a number of legumes and may contribute to ligand binding preferences. The diversification of KAI2 binding pockets suggests the occurrence of several different KLs acting in non-fire following plants, or an escape from possible antagonistic exogenous molecules. Unexpectedly, L. japonicus responds to diverse synthetic KAI2-ligands in an organ-specific manner. Hypocotyl growth responds to KAR1, KAR2 and rac-GR24, while root system development responds only to KAR1. This differential responsiveness cannot be explained by receptor-ligand preferences alone, because LjKAI2a is sufficient for karrikin responses in the hypocotyl, while LjKAI2a and LjKAI2b operate redundantly in roots. Instead, it likely reflects differences between plant organs in their ability to transport or metabolise the synthetic KLs. Our findings provide new insights into the evolution and diversity of butenolide ligand-receptor relationships, and open novel research avenues into their ecological significance and the mechanisms controlling developmental responses to divergent KLs.


Assuntos
Proteínas de Arabidopsis/genética , Furanos/metabolismo , Hidrolases/genética , Hipocótilo/crescimento & desenvolvimento , Lotus/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Piranos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Furanos/química , Duplicação Gênica , Regulação da Expressão Gênica de Plantas/genética , Compostos Heterocíclicos com 3 Anéis/metabolismo , Hidrolases/metabolismo , Hipocótilo/metabolismo , Lactonas/metabolismo , Ligantes , Lotus/genética , Análise em Microsséries , Filogenia , Reguladores de Crescimento de Planta/química , Reguladores de Crescimento de Planta/genética , Raízes de Plantas/metabolismo , Piranos/química
15.
Acta Crystallogr C Struct Chem ; 76(Pt 9): 914-920, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887863

RESUMO

The terpenoid (-)-Istanbulin A is a natural product isolated from Senecio filaginoides DC, one of the 270 species of Senecio (Asteraceae) which occurs in Argentina. The structure and absolute configuration of this compound [9a-hydroxy-3,4a,5-trimethyl-4a,6,7,8a,9,9a-hexahydro-4H,5H-naphtho[2,3-b]-furan-2,8-dione or (4S,5R,8R,10S)-1-oxo-8ß-hydroxy-10ßH-eremophil-7(11)-en-12,8ß-olide, C15H20O4] were determined by single-crystal X-ray diffraction studies. It proved to be a sesquiterpene lactone showing an eremophilanolide skeleton whose chirality is described as 4S,5R,8R,10S. Structural results were also in agreement with the one- and two-dimensional (1D and 2D) NMR and HR-ESI-MS data, and other complementary spectroscopic information. In addition, (-)-Istanbulin A is a polymorph of the previously reported form of (-)-Istanbulin A, form I; thus, the title compound is denoted form II or polymorph II. Structural data and a literature search allowed the chirality of Istanbulin A to be revisited. The antimicrobial and antifungal activities of (-)-Istanbulin A, form II, were evaluated in order to establish a reference for future comparisons and applications related to specific crystal forms of Istanbulins.


Assuntos
Antifúngicos/química , Furanos/química , Sesquiterpenos/química , Cristalografia por Raios X , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Estereoisomerismo
16.
Antimicrob Agents Chemother ; 64(11)2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32868327

RESUMO

Remdesivir has reported efficacy against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in vitro and in vivo Drug-drug interactions limit therapeutic options in transplant patients. Remdesivir and its metabolite GS-441524 are excreted principally in urine. In intensive care unit (ICU) settings, in which multiple-organ dysfunctions can occur rapidly, hemodialysis may be a viable option for maintaining remdesivir treatment, while improving tolerance, by removing both remdesivir's metabolite (GS-441524) and sulfobutylether ß-cyclodextrin sodium (SEBCD). Additional studies may prove informative, particularly in the evaluations of therapeutic options for coronavirus disease 2019 (COVID-19).


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/administração & dosagem , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/terapia , Furanos/urina , Pneumonia Viral/terapia , Pirróis/urina , Triazinas/urina , beta-Ciclodextrinas/urina , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/efeitos adversos , Monofosfato de Adenosina/química , Monofosfato de Adenosina/metabolismo , Alanina/administração & dosagem , Alanina/efeitos adversos , Alanina/química , Alanina/metabolismo , Antivirais/efeitos adversos , Antivirais/química , Antivirais/metabolismo , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/cirurgia , Infecções por Coronavirus/virologia , Interações Medicamentosas , Furanos/efeitos adversos , Furanos/química , Humanos , Unidades de Terapia Intensiva , Transplante de Pulmão , Insuficiência de Múltiplos Órgãos , Pandemias , Pneumonia Viral/cirurgia , Pneumonia Viral/virologia , Pirróis/efeitos adversos , Pirróis/química , Diálise Renal , Transplantados , Triazinas/efeitos adversos , Triazinas/química , beta-Ciclodextrinas/efeitos adversos , beta-Ciclodextrinas/química
17.
J Chromatogr A ; 1626: 461369, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797848

RESUMO

Pumped sorbent tube sampling is a well established method for the sampling of volatile organic compounds (VOCs) and semi volatile organic compounds (SVOCs) in ambient, indoor and workplace atmospheres1. Safe sampling volumes and breakthrough volumes have been published for commonly found VOCs on widely used sorbents such as Tenax, however for newer sorbents and less commonly found VOCs there is less robust data. The Safe Sampling Volumes (SSVs) were determined from 15 tests of Retention Volume on 12 VOCs across the 3 sorbents. VOCs tested were: Aldehydes (C5, C6, C8, C9), Ketones (C4, C6), Alcohols (C3, C4), Furan, Limonene, Isoprene and Ethyl Acetate. 12 VOC / sorbent combinations gave SSVs large enough for practical sampling of indoor atmospheres, while SSVs for Furan on Carbopack-X, Isovaleraldehyde on Tenax TA and Methyl Ethyl Ketone on Tenax TA gave SSVs that were too small to be of practical use. This work identifies suitable sorbents and sampling volumes for the complete range of species tested.


Assuntos
Cromatografia Gasosa/métodos , Polímeros/química , Compostos Orgânicos Voláteis/análise , Adsorção , Poluição do Ar em Ambientes Fechados/análise , Aldeídos/química , Monitoramento Ambiental , Furanos/química , Compostos Orgânicos Voláteis/química
18.
Toxicol Lett ; 333: 202-210, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32814080

RESUMO

OBJECTIVES: Determine uptake of furan, a potential human carcinogen, in waterpipe tobacco (WPT) smokers in home settings. METHODS: We analysed data from a US convenience sample of 50 exclusive WPT smokers, mean age 25.3 years, and 25 non-smokers, mean age 25.5 years. For WPT smokers, data were collected at a home visit by research assistants during which participants smoked one WPT head of one brand for a mean of 33.1 min in their homes. Research assistants provided and prepared a WP for participants by weighing and loading 10 g of WPT in the WP head. At the completion of the smoking session, research assistants measured the remaining WPT. Cotinine and six furan metabolites were quantified in first morning urine samples provided on 2 consecutive days for non-smokers, and on the morning of a WPT smoking session and on the following morning for smokers. RESULTS: WPT smokers consumed a mean of 2.99 g WPT. In WPT smokers, urinary cotinine levels increased significantly 26.1 times the following morning; however, urinary metabolites of furan did not increase significantly. Compared to non-smokers, 2 furan metabolites, N-acetyl-S-[1-(5-acetylamino-5-carboxylpentyl)-1H-pyrrol-3-yl]-L-cysteine and N-acetyl-S-[1-(5-amino-5-carboxypentyl)-1H-pyrrol-3-yl]-L-cysteine sulfoxide, were significantly higher in WPT smokers in pre and in post WPT smoking levels. CONCLUSIONS: To enable a more rigorous assessment of furan exposure from WPT smoking, future research should determine furan concentrations in WPT smoke, quantify furan metabolites from users of various WPT brands; and extend the investigation to social settings where WPT smoking is habitually practiced.


Assuntos
Furanos/urina , não Fumantes , Fumantes , Fumar/urina , Tabaco para Cachimbos de Água/toxicidade , Adulto , Estudos de Casos e Controles , Cotinina/urina , Furanos/química , Furanos/metabolismo , Humanos , Masculino , Estrutura Molecular , Fumar/efeitos adversos , Fumar/metabolismo , Tabaco para Cachimbos de Água/análise
19.
Int J Nanomedicine ; 15: 5073-5082, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764937

RESUMO

Objective: To prepare xanthatin (XA)-loaded polydopamine (PDA) nanoparticles (PDA-XA-NPs) and to investigate their adhesion and bioavailability. Materials and methods: PDA-XA-NPs were synthesized and characterized using transmission electron microscopy, zeta potential analysis and encapsulation efficiency analysis. Their in vitro release kinetics and inhibitory effects on gastric cancer were studied. The adhesion of PDA-XA-NPs was evaluated by in vivo imaging atlas. The pharmacokinetics of PDA-XA-NPs and XA was compared. Results: PDA-XA-NPs had a spherical shape, a particle size of about 380 nm, an encapsulation efficiency of (82.1 ± 0.02) % and a drug loading capacity of (5.5 ± 0.1)%. The release of PDA-XA-NPs in PBS was stable and slow, without being affected by pH. The adhesion capacity of PDA-XA-NPs for mucin was significantly higher than that of bulk drug. The gastric mucosal retention of PDA-XA-NPs reached 89.1% which significantly exceeded that of XA. In vivo imaging showed that PDA-XA-NPs targeting the stomach were retained for a period of time. The pharmacokinetics study showed that PDA-XA-NPs had a longer retention time and a slower drug release than those of XA. In vitro experiments confirmed that PDA-XA-NPs exerted similar inhibitory effects on gastric cancer to those of XA, which lasted for a period of time. Conclusion: High-adhesion NPs were constructed. Gastric cancer was targeted by orally administered PDA-XA-NPs, as a potentially feasible therapy. Eventually, the bioavailability of XA was increased.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Furanos/farmacocinética , Nanopartículas/química , Neoplasias Gástricas/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/química , Disponibilidade Biológica , Linhagem Celular Tumoral , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Furanos/química , Mucosa Gástrica/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Indóis/química , Masculino , Camundongos Endogâmicos ICR , Microscopia Eletrônica de Transmissão , Nanopartículas/metabolismo , Tamanho da Partícula , Polímeros/química , Ratos Sprague-Dawley , Neoplasias Gástricas/patologia
20.
Nucleic Acids Res ; 48(14): 7653-7664, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32667657

RESUMO

Small molecule-based modulation of a triple helix in the long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) has been proposed as an attractive avenue for cancer treatment and a model system for understanding small molecule:RNA recognition. To elucidate fundamental recognition principles and structure-function relationships, we designed and synthesized nine novel analogs of a diphenylfuran-based small molecule DPFp8, a previously identified lead binder of MALAT1. We investigated the role of recognition modalities in binding and in silico studies along with the relationship between affinity, stability and in vitro enzymatic degradation of the triple helix. Specifically, molecular docking studies identified patterns driving affinity and selectivity, including limited ligand flexibility, as observed by ligand preorganization and 3D shape complementarity for the binding pocket. The use of differential scanning fluorimetry allowed rapid evaluation of ligand-induced thermal stabilization of the triple helix, which correlated with decreased in vitro degradation of this structure by the RNase R exonuclease. The magnitude of stabilization was related to binding mode and selectivity between the triple helix and its precursor stem loop structure. Together, this work demonstrates the value of scaffold-based libraries in revealing recognition principles and of raising broadly applicable strategies, including functional assays, for small molecule-RNA targeting.


Assuntos
Furanos/química , RNA Longo não Codificante/química , Exorribonucleases/metabolismo , Furanos/síntese química , Ligantes , Simulação de Acoplamento Molecular , Conformação de Ácido Nucleico , Estabilidade de RNA , RNA Longo não Codificante/metabolismo
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