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1.
Forensic Sci Int ; 359: 112030, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657324

RESUMO

The use of 3,4-methylenedioxymethamphetamine (MDMA) in drug-facilitated sexual assault (DFSA) is not uncommon. Indeed, the effects associated with the use of this substance may lead to disinhibition. Several synthetic cathinones, such as mephedrone or methylone, also possess marked entactogenic properties. This manuscript aims to (i) report a DFSA case involving a novel cathinone derivative, namely N-ethyl-pentedrone (NEPD) and (ii) review previously reported DFSA cases involving synthetic cathinones. Using liquid chromatography-high-resolution mass spectrometry (LC-HRMS), NEPD was detected in both plasma and urine collected from a 36-year-old male who had been victim of DFSA. Furthermore, an exhaustive, non-period-specific English-language literature search was performed using several different electronic databases to identify DFSA cases involving synthetic cathinones. Overall, five synthetic cathinones have been associated with DFSA:methylenedioxypyrovalerone, 4-methylethcathinone, α -pyrrolidinopentiophenone, mephedrone, α -pyrrolidinohexiophenone, and methylone, which appears to be the most frequently reported. Methylone is the ß-keto analog of MDMA, with which it shares substantial pharmacological similarities. Indeed, the pharmacological effects of methylone are similar to those associated with MDMA. By contrast, little is known regarding NEPD's pharmacological effects in humans. Based on subjective reports, NEPD can produce both positive and negative effects in human. Unlike what is reported in the case of methylone or mephedrone, only a small minority of NEPD users report slightly entactogenics effects. Such properties theoretically make NEPD more suitable for use in a chemsex context than in DFSA context; even though, the boundary between these two specific forms of sexualized drug use can sometimes appear tenuous.


Assuntos
Alcaloides , Espectrometria de Massas , Humanos , Masculino , Adulto , Cromatografia Líquida , Alcaloides/análise , Drogas Desenhadas/efeitos adversos , Drogas Desenhadas/análise , Pentanonas/química , Estupro
2.
Pharm Dev Technol ; 29(4): 339-352, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38502579

RESUMO

We recently reported the potential of a new gallium compound, gallium acetylacetonate (GaAcAc) in combating osteoclastic bone resorption through inhibition of osteoclast differentiation and function. Herein, we focused on 3D-printed polylactic acid scaffolds that were loaded with GaAcAc and investigated the impact of scaffold pretreatment with polydopamine (PDA) or sodium hydroxide (NaOH). We observed a remarkable increase in scaffold hydrophilicity with PDA or NaOH pretreatment while biocompatibility and in vitro degradation were not affected. NaOH-pretreated scaffolds showed the highest amount of GaAcAc loading when compared to other scaffolds (p < 0.05). NaOH-pretreated scaffolds with GaAcAc loading showed effective reduction of osteoclast counts and size. The trend was supported by suppression of key osteoclast differentiation markers such as NFAT2, c-Fos, TRAF6, & TRAP. All GaAcAc-loaded scaffolds, regardless of surface pretreatment, were effective in inhibiting osteoclast function as evidenced by reduction in the number of resorptive pits in bovine cortical bone slices (p < 0.01). The suppression of osteoclast function according to the type of scaffold followed the ranking: GaAcAc loading without surface pretreatment > GaAcAc loading with NaOH pretreatment > GaAcAc loading with PDA pretreatment. Additional studies will be needed to fully elucidate the impact of surface pretreatment on the efficacy and safety of GaAcAc-loaded 3D-printed scaffolds.


Assuntos
Reabsorção Óssea , Osteoclastos , Impressão Tridimensional , Alicerces Teciduais , Animais , Osteoclastos/efeitos dos fármacos , Alicerces Teciduais/química , Reabsorção Óssea/tratamento farmacológico , Bovinos , Camundongos , Poliésteres/química , Gálio/química , Gálio/farmacologia , Pentanonas/química , Pentanonas/administração & dosagem , Pentanonas/farmacologia , Hidróxido de Sódio , Diferenciação Celular/efeitos dos fármacos
3.
J Environ Sci (China) ; 141: 225-234, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38408823

RESUMO

Acetylacetone (AcAc) is a typical class of ß-diketones with broad industrial applications due to the property of the keto-enol isomers, but its isomerization and chemical reactions at the air-droplet interface are still unclear. Hence, using combined molecular dynamics and quantum chemistry methods, the heterogeneous chemistry of AcAc at the air-droplet interface was investigated, including the attraction of AcAc isomers by the droplets, the distribution of isomers at the air-droplet interface, and the hydration reactions of isomers at the air-droplet interface. The results reveal that the preferential orientation of two AcAc isomers (keto- and enol-AcAc) to accumulate and accommodate at the acidic air-droplet interface. The isomerization of two AcAc isomers at the acidic air-droplet interface is more favorable than that at the neutral air-droplet interface because the "water bridge" structure is destroyed by H3O+, especially for the isomerization from keto-AcAc to enol-AcAc. At the acidic air-droplet interface, the carbonyl or hydroxyl O-atoms of two AcAc isomers display an energetical preference to hydration. Keto-diol is the dominant products to accumulate at the air-droplet interface, and excessive keto-diol can enter the droplet interior to engage in the oligomerization. The photooxidation reaction of AcAc will increase the acidity of the air-droplet interface, which indirectly facilitate the uptake and formation of more keto-diol. Our results provide an insight into the heterogeneous chemistry of ß-diketones and their influence on the environment.


Assuntos
Pentanonas , Água , Isomerismo , Pentanonas/química , Água/química
4.
J Am Chem Soc ; 143(42): 17452-17464, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34643382

RESUMO

Ketone enolization by sodium hexamethyldisilazide (NaHMDS) shows a marked solvent and substrate dependence. Enolization of 2-methyl-3-pentanone reveals E-Z selectivities in Et3N/toluene (20:1), methyl-t-butyl ether (MTBE, 10:1), N,N,N',N″,N″-pentamethyldiethylenetriamine (PMDTA)/toluene (8:1), TMEDA/toluene (4:1), diglyme (1:1), DME (1:22), and tetrahydrofuran (THF) (1:90). Control experiments show slow or nonexistent stereochemical equilibration in all solvents except THF. Enolate trapping with Me3SiCl/Et3N requires warming to -40 °C whereas Me3SiOTf reacts within seconds. In situ enolate trapping at -78 °C using preformed NaHMDS/Me3SiCl mixtures is effective in Et3N/toluene yet fails in THF by forming (Me3Si)3N. Rate studies show enolization via mono- and disolvated dimers in Et3N/toluene, disolvated dimers in TMEDA, trisolvated monomers in THF/toluene, and free ions with PMDTA. Density functional theory computations explore the selectivities via the E- and Z-based transition structures. Failures of theory-experiment correlations of ionic fragments were considerable even when isodesmic comparisons could have canceled electron correlation errors. Swapping 2-methyl-3-pentanone with a close isostere, 2-methylcyclohexanone, causes a fundamental change in the mechanism to a trisolvated-monomer-based enolization in THF.


Assuntos
Compostos de Organossilício/química , Pentanonas/química , Solventes/química , Deutério/química , Cinética , Modelos Químicos , Estereoisomerismo
5.
Chem Commun (Camb) ; 57(74): 9462-9465, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34528953

RESUMO

We here report a manganese-based oxidative cleavage of inactivated acetylacetonate, the mechanistic pathway of which resembles Dke1-catalyzed reactions of ß-diketone and α-keto acid. This oxidative transformation proceeds through an acetylacetonate-pyruvate-oxalate pathway, which can be terminated at the stage of pyruvate through ligand/solvent variation. XRD, time-dependent GC-MS, and isotope-labeling studies suggested that our system represents the same cleaving specificity and dioxygenase-like reactivity of Dke1.


Assuntos
Dioxigenases/metabolismo , Hidroxibutiratos/metabolismo , Cetonas/metabolismo , Manganês/metabolismo , Pentanonas/metabolismo , Dioxigenases/química , Hidroxibutiratos/química , Cetonas/química , Manganês/química , Estrutura Molecular , Pentanonas/química
7.
Molecules ; 26(18)2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34577005

RESUMO

Vanadium has a good therapeutic potential, as several biological effects, but few side effects, have been demonstrated. Evidence suggests that vanadium compounds could represent a new class of non-platinum, metal antitumor agents. In the present study, we aimed to characterize the antiproliferative activities of fluorescent vanadyl complexes with acetylacetonate derivates bearing asymmetric substitutions on the ß-dicarbonyl moiety on different cell lines. The effects of fluorescent vanadyl complexes on proliferation and cell cycle modulation in different cell lines were detected by ATP content using the CellTiter-Glo Luminescent Assay and flow cytometry, respectively. Western blotting was performed to assess the modulation of mitogen-activated protein kinases (MAPKs) and relevant proteins. Confocal microscopy revealed that complexes were mainly localized in the cytoplasm, with a diffuse distribution, as in podocyte or a more aggregate conformation, as in the other cell lines. The effects of complexes on cell cycle were studied by cytofluorimetry and Western blot analysis, suggesting that the inhibition of proliferation could be correlated with a block in the G2/M phase of cell cycle and an increase in cdc2 phosphorylation. Complexes modulated mitogen-activated protein kinases (MAPKs) activation in a cell-dependent manner, but MAPK modulation can only partly explain the antiproliferative activity of these complexes. All together our results demonstrate that antiproliferative effects mediated by these compounds are cell type-dependent and involve the cdc2 and MAPKs pathway.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Hidroxibutiratos/química , Pentanonas/química , Compostos de Vanádio/química , Compostos de Vanádio/farmacologia , Transporte Biológico , Proteína Quinase CDC2/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Corantes Fluorescentes , Humanos , Concentração Inibidora 50 , Microscopia Confocal , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Podócitos/efeitos dos fármacos , Podócitos/ultraestrutura , Inibidores de Proteínas Quinases/farmacologia
8.
J Am Chem Soc ; 143(19): 7480-7489, 2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-33949855

RESUMO

Intramolecular alkoxylation of C-H bonds can rapidly introduce structural and functional group complexities into seemingly simple or inert precursors. The transformation is particularly important due to the ubiquitous presence of tetrahydrofuran (THF) motifs as fundamental building blocks in a wide range of pharmaceuticals, agrochemicals, and natural products. Despite the various synthetic methodologies known for generating functionalized THFs, most show limited functional group tolerance and lack demonstration for the preparation of spiro or fused bi- and tricyclic ether units prevalent in molecules for pharmacological purposes. Herein we report an intramolecular C-H alkoxylation to furnish oxacycles from easily prepared α-diazo-ß-ketoesters using commercially available iron acetylacetonate (Fe(acac)2) as a catalyst. The reaction is proposed to proceed through the formation of a vinylic carboradical arising from N2 extrusion, which mediates a proximal H-atom abstraction followed by a rapid C-O bond forming radical recombination step. The radical mechanism is probed using an isotopic labeling study (vinyl C-D incorporation), ring opening of a radical clock substrate, and Hammett analysis and is further corroborated by density functional theory (DFT) calculations. Heightened reactivity is observed for electron-rich C-H bonds (tertiary, ethereal), while greater catalyst loadings or elevated reaction temperatures are required to fully convert substrates with benzylic, secondary, and primary C-H bonds. The transformation is highly functional group tolerant and operates under mild reaction conditions to provide rapid access to complex structures such as spiro and fused bi-/tricyclic O-heterocycles from readily available precursors.


Assuntos
Compostos Heterocíclicos/síntese química , Hidroxibutiratos/química , Ferro/química , Pentanonas/química , Catálise , Compostos Heterocíclicos/química , Modelos Moleculares , Estrutura Molecular
9.
Int J Mol Sci ; 22(8)2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33921452

RESUMO

The three complexes [Fe(opo)3], [Cu(opo)2], and [Zn(opo)2] containing the non-innocent anionic ligand opo- (opo- = 9-oxido-phenalenone, Hopo = 9-hydroxyphenalonone) were synthesised from the corresponding acetylacetonates. [Zn(opo)2] was characterised using 1H nuclear magnetic resonance (NMR) spectroscopy, the paramagnetic [Fe(opo)3] and [Cu(opo)2] by electron paramagnetic resonance (EPR) spectroscopy. While the EPR spectra of [Cu(opo)2] and [Cu(acac)2] in dimethylformamide (DMF) solution are very similar, a rather narrow spectrum was observed for [Fe(opo)3] in tetrahydrofuran (THF) solution in contrast to the very broad spectrum of [Fe(acac)3] in THF (Hacac = acetylacetone, 2,4-pentanedione; acac- = acetylacetonate). The narrow, completely isotropic signal of [Fe(opo)3] disagrees with a metal-centred S = 5/2 spin system that is observed in the solid state. We assume spin-delocalisation to the opo ligand in the sense of an opo- to FeIII electron transfer. All compounds show several electrochemical opo-centred reduction waves in the range of -1 to -3 V vs. the ferrocene/ferrocenium couple. However, for CuII and FeIII the very first one-electron reductions are metal-centred. Electronic absorption in the UV to vis range are due to π-π* transitions in the opo core, giving Hopo and [Zn(opo)2] a yellow to orange colour. The structured bands ranging from 400 to 500 for all compounds are assigned to the lowest energy π-π* transitions. They show markedly higher intensities and slight shifts for the CuII (brown) and FeIII (red) complexes and we assume admixing metal contributions (MLCT for CuII, LMCT for FeIII). For both complexes long-wavelength absorptions assignable to d-d transitions were detected. Detailed spectroelectrochemical experiments confirm both the electrochemical and the optical assignments. Hopo and the complexes [Cu(opo)2], [Zn(opo)2], and [Fe(opo)3] show antiproliferative activities against HT-29 (colon cancer) and MCF-7 (breast cancer) cell lines in the range of a few µM, comparable to cisplatin under the same conditions.


Assuntos
Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Neoplasias/tratamento farmacológico , Pentanonas/química , Cisplatino/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Cobre/química , Eletroquímica , Células HT29 , Humanos , Ferro/química , Ligantes , Células MCF-7 , Neoplasias/patologia , Pentanonas/síntese química , Pentanonas/farmacologia , Fenalenos/química , Análise Espectral , Zinco/química
10.
ACS Appl Mater Interfaces ; 13(16): 19312-19323, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33871259

RESUMO

With diverse selectivity, higher permeance, and good antifouling property, loose polyamide nanofiltration (NF) membranes can be potentially deployed in various bioseparation applications. However, the loose NF membrane with a low crosslinking degree generally suffers from the alkali-induced pore swelling during chemical cleaning, resulting in degradation of separation performance with time. In this work, we conceive a novel strategy to tailor the separating layer through alkaline post-etching following the interfacial polymerization process, where piperazine and tannic acid (TA) were used as water-phase monomers, and trimesoyl chloride (TMC) and ferric acetylacetonate were employed as organic monomers in n-hexane. Thereinto, the polyester network formed by TA and TMC was selectively etched by alkaline treatment, thus obtaining a loose NF membrane, whose structure and performance could be facilely tailored by controlling the TA ratio and the etching pH. As a result, the well-designed loose NF membrane exhibited higher flux, better selectivity, and more stable separation performance in a long-term filtration of diluted cane molasses. Interestingly, the obtained loose NF membrane showed excellent antiswelling ability during alkaline cleaning because of network locking induced by Fe3+ chelation, decrease in the carboxyl proportion (more hydroxyl generation due to the ester bond hydrolysis), and enhanced interface interaction between the separation layer and the sublayer attributed to catechol adhesion effect. Therefore, such a "selective-etching-induced reinforcing" strategy could endow the polyamide NF membrane with both loose and antiswelling separation layer in a reliable and scalable way, which provides a new perspective for preparing highly selective and stable NF membrane for resource recovery.


Assuntos
Filtração/métodos , Membranas Artificiais , Nanotecnologia/métodos , Concentração de Íons de Hidrogênio , Hidroxibutiratos/química , Pentanonas/química , Piperazina/química , Polimerização , Taninos/química , Fatores de Tempo , Água/química
11.
Toxicol Appl Pharmacol ; 416: 115442, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33609514

RESUMO

Cathinone derivatives are the most representative group within new drugs market, which have been described as neurotoxic. Since cathinones, as pentedrone and methylone, are available as racemates, it is our aim to study the neuronal cytotoxicity induced by each enantiomer. Therefore, a dopaminergic SH-SY5Y cell line was used to evaluate the hypothesis of enantioselectivity of pentedrone and methylone enantiomers on cytotoxicity, oxidative stress, and membrane efflux transport (confirmed by in silico studies). Our study demonstrated enantioselectivity of these cathinones, being the S-(+)-pentedrone and R-(+)-methylone the most oxidative enantiomers and also the most cytotoxic, suggesting the oxidative stress as main cytotoxic mechanism, as previously described in in vitro studies. Additionally, the efflux transporter multidrug resistance associated protein 1 (MRP1) seems to play, together with GSH, a selective protective role against the cytotoxicity induced by R-(-)-pentedrone enantiomer. It was also observed an enantioselectivity in the binding to P-glycoprotein (P-gp), another efflux protein, being the R-(-)-pentedrone and S-(-)-methylone the most transported enantiomeric compounds. These results were confirmed, in silico, by docking studies, revealing that R-(-)-pentedrone is the enantiomer with highest affinity to MRP1 and S-(-)-methylone and R-(-)-pentedrone are the enantiomers with highest affinity to P-gp. In conclusion, our data demonstrated that pentedrone and methylone present enantioselectivity in their cytotoxicity, which seems to involve different oxidative reactivity as well as different affinity to the P-gp and MRP1 that together with GSH play a protective role.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Alcaloides/toxicidade , Neurônios Dopaminérgicos/efeitos dos fármacos , Metanfetamina/análogos & derivados , Metilaminas/toxicidade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pentanonas/toxicidade , Alcaloides/química , Alcaloides/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Humanos , Metanfetamina/química , Metanfetamina/metabolismo , Metanfetamina/toxicidade , Metilaminas/química , Metilaminas/metabolismo , Simulação de Acoplamento Molecular , Pentanonas/química , Pentanonas/metabolismo , Ligação Proteica , Estereoisomerismo
12.
Nat Prod Res ; 35(19): 3204-3209, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31711315

RESUMO

A new phenylpentenol, wortmannine H (1) was isolated from Talaromyces wortmannii LGT-4, an endophytic fungus of Tripterygium wilfordii. The structure of 1 was elucidated by IR, MS, 1D and 2D NMR spectra and comparison of the experimental and calculated optical rotatory dispersion (ORD). Monoamine oxidase (MAO), acetylcholinesterase (AChE) and phosphoinositide 3-kinase (PI3Kα) inhibitory activities of 1 was also tested. The compound did not show good biological activity.


Assuntos
Pentanonas/química , Talaromyces , Acetilcolinesterase , Endófitos , Estrutura Molecular , Monoaminoxidase , Pentanonas/isolamento & purificação , Fosfatidilinositol 3-Quinases , Talaromyces/química
13.
Parasitol Res ; 119(9): 2991-3003, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32748038

RESUMO

Visceral leishmaniasis (VL, also known as kala-azar) is a vector borne disease caused by obligate intracellular protozoan parasite Leishmania donovani. To overcome the limitations of currently available drugs for VL, molecular target-based study is a promising tool to develop new drugs to treat this neglected tropical disease. One such target we recently identified from L. donovani (Ld) genome (WGS, clinical Indian isolate; BHU 1220, AVPQ01000001) is a small GTP-binding protein, Rab6 protein. We now report a specific inhibitor of the GTPase activity of Rab6 protein of L. donovani (LdRab6) without restricting host enzyme activity. First, to understand the nature of LdRab6 protein, we generated recombinant LdRab6 mutant proteins (rLdRab6) by systematically introducing deletion (two cysteine residues at C-terminal) and mutations [single amino acid substitutions in the conserved region of GTP (Q84L)/GDP(T38N) coding sequence]. The GTPase activity of rLdRab6:GTP and rLdRab6:GDP locked mutant proteins showed ~ 8-fold and ~ 1.5-fold decreases in enzyme activity, respectively, compared to the wild type enzyme activity. The mutant protein rLdRab6:ΔC inhibited the GTPase activity. Sequence alignment analysis of Rab6 protein of L. donovani with Homo sapiens showed identical amino acids in the G conserved region (GTP/GDP-binding sites) but it differed in the C-terminal region. We then evaluated the inhibitory activity of trans-dibenzalacetone (DBA, a synthetic analog of curcumin with strong antileishmanial activity reported earlier by us) in the GTPase activity of LdRab6 protein. Comparative molecular docking analysis of DBA and specific inhibitors of Rab proteins (Lovastatin, BFA, Zoledronate, and NE10790) indicated that DBA had optimum binding affinity with LdRab6 protein. This was further confirmed by the GTPase activity of DBA-treated LdRab6 which showed a basal GTP level significantly lower than that of the wild-type rLdRab6. The results confirm that DBA inhibits the GTPase activity of LdRab6 protein from L. donovani (LdRab6), a potential target for its antileishmanial effect.


Assuntos
Antiprotozoários/farmacologia , Inibidores Enzimáticos/farmacologia , Leishmania donovani/efeitos dos fármacos , Leishmaniose Visceral/parasitologia , Pentanonas/farmacologia , Proteínas de Protozoários/antagonistas & inibidores , Proteínas rab de Ligação ao GTP/antagonistas & inibidores , Sequência de Aminoácidos , Sítios de Ligação , Curcumina/farmacologia , Humanos , Leishmania donovani/química , Leishmania donovani/enzimologia , Leishmania donovani/genética , Leishmaniose Visceral/tratamento farmacológico , Simulação de Acoplamento Molecular , Pentanonas/química , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Alinhamento de Sequência , Proteínas rab de Ligação ao GTP/química , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
14.
Molecules ; 25(13)2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32610466

RESUMO

A series of 18 regio- and stereo-chemically diverse chiral non-racemic 1,2-, 1,3-, and 1,4-diamines have been synthesized from commercial (1S)-(+)-ketopinic acid and (1S)-(+)-10-camphorsulfonic acid. The structures of the diamines are all based on the d-(+)-camphor scaffold and feature isomeric diversity in terms of regioisomeric attachment of the primary and the tertiary amine function and the exo/endo-isomerism. Diamines were transformed into the corresponding noncovalent bifunctional thiourea organocatalysts, which have been evaluated for catalytic activity in the conjugative addition of 1,3-dicarbonyl nucleophiles (dimethyl malonate, acetylacetone, and dibenzoylmethane) to trans-ß-nitrostyrene. The highest enantioselectivity was achieved in the reaction with acetylacetone as nucleophile using endo-1,3-diamine derived catalyst 52 (91.5:8.5 er). All new organocatalysts 48-63 have been fully characterized. The structures and the absolute configurations of eight intermediates and thiourea derivative 52 were also determined by X-ray diffraction.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/síntese química , Cânfora/química , Diaminas/química , Cetonas/síntese química , Nitrocompostos/química , Hidrocarbonetos Aromáticos com Pontes/química , Cânfora/síntese química , Catálise , Diaminas/síntese química , Cetonas/química , Modelos Moleculares , Estrutura Molecular , Nitrocompostos/síntese química , Pentanonas/química , Tioureia/química
15.
J Vis Exp ; (160)2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32628168

RESUMO

For biomedical applications, metal oxide nanoparticles such as iron oxide and manganese oxide (MnO), have been used as biosensors and contrast agents in magnetic resonance imaging (MRI). While iron oxide nanoparticles provide constant negative contrast on MRI over typical experimental timeframes, MnO generates switchable positive contrast on MRI through dissolution of MnO to Mn2+ at low pH within cell endosomes to 'turn ON' MRI contrast. This protocol describes a one-pot synthesis of MnO nanoparticles formed by thermal decomposition of manganese(II) acetylacetonate in oleylamine and dibenzyl ether. Although running the synthesis of MnO nanoparticles is simple, the initial experimental setup can be difficult to reproduce if detailed instructions are not provided. Thus, the glassware and tubing assembly is first thoroughly described to allow other investigators to easily reproduce the setup. The synthesis method incorporates a temperature controller to achieve automated and precise manipulation of the desired temperature profile, which will impact resulting nanoparticle size and chemistry. The thermal decomposition protocol can be readily adapted to generate other metal oxide nanoparticles (e.g., iron oxide) and to include alternative organic solvents and stabilizers (e.g., oleic acid). In addition, the ratio of organic solvent to stabilizer can be changed to further impact nanoparticle properties, which is shown herein. Synthesized MnO nanoparticles are characterized for morphology, size, bulk composition, and surface composition through transmission electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy, respectively. The MnO nanoparticles synthesized by this method will be hydrophobic and must be further manipulated through ligand exchange, polymeric encapsulation, or lipid capping to incorporate hydrophilic groups for interaction with biological fluids and tissues.


Assuntos
Hidroxibutiratos/química , Compostos de Manganês/química , Manganês/química , Nanopartículas Metálicas/química , Óxidos/química , Pentanonas/química , Temperatura , Vidro/química , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas Metálicas/ultraestrutura , Nitrogênio/química , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Água/química , Difração de Raios X
16.
Toxicol Lett ; 331: 42-52, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32464236

RESUMO

Synthetic cathinones abuse remains a serious public health problem. Kidney injury has been reported in intoxications associated with synthetic cathinones, but the molecular mechanisms involved have not been explored yet. In this study, the potential in vitro nephrotoxic effects of four commonly abused cathinone derivatives, namely pentedrone, 3,4-dimethylmethcatinone (3,4-DMMC), methylone and 3,4-methylenedioxypyrovalerone (MDPV), were assessed in the human kidney HK-2 cell line. All four derivatives elicited cell death in a concentration- and time-dependent manner, in the following order of potency: 3,4-DMMC >> MDPV > methylone ≈ pentedrone. 3,4-DMMC and methylone were selected to further elucidate the mechanisms behind synthetic cathinones-induced cell death. Both drugs elicited apoptotic cell death and prompted the formation of acidic vesicular organelles and autophagosomes in HK-2 cells. Moreover, the autophagy inhibitor 3-methyladenine significantly potentiated cell death, indicating that autophagy may serve as a cell survival mechanism that protects renal cells against synthetic cathinones toxicity. Both drugs triggered a rise in reactive oxygen and nitrogen species formation, which was completely prevented by antioxidant treatment with N­acetyl­L­cysteine or ascorbic acid. Importantly, these antioxidant agents significantly aggravated renal cell death induced by cathinone derivatives, most likely due to their autophagy-blocking properties. Taken together, our results support an intricate control of cell survival/death modulated by oxidative stress, apoptosis and autophagy in synthetic cathinones-induced renal injury.


Assuntos
Alcaloides/toxicidade , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Drogas Ilícitas/toxicidade , Rim/efeitos dos fármacos , Alcaloides/química , Benzodioxóis/química , Benzodioxóis/toxicidade , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Rim/metabolismo , Rim/patologia , Metanfetamina/análogos & derivados , Metanfetamina/química , Metanfetamina/toxicidade , Metilaminas/química , Metilaminas/toxicidade , Pentanonas/química , Pentanonas/toxicidade , Pirrolidinas/química , Pirrolidinas/toxicidade , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo , Catinona Sintética
17.
Chem Pharm Bull (Tokyo) ; 68(5): 447-451, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32378542

RESUMO

Catechol O-methyltransferase (COMT) is known as an important drug-target protein in the field of Parkinson's disease. All clinically approved COMT inhibitors bring a 5-substituted-3-nitrocatechol ring as a pharmacophore, and they bind to COMT with S-adenosylmethionine (SAM) and an Mg2+ ion to form a quaternary complex (COMT/SAM/Mg2+/inhibitor). However, structural information about such quaternary complexes is only available for a few inhibitors. Here, a new crystal structure of COMT complexed with nitecapone (5), SAM and Mg2+ is revealed. Comparison of the structures of these complexes indicates that conformation of the catechol binding pocket is almost constant regardless of structure of the inhibitors. The only restriction of the side chain of inhibitors (i.e., the substituent at the 5-position of 3-nitrocatechol) seems to be that it does not make steric repulsion with COMT. However, recent crystallographic and biochemical studies suggest that COMT is a flexible protein, and its conformational flexibility seems crucial for its catalytic process. Based on this information, implications of these quaternary inhibitor complexes were investigated. Met 40 in the α2α3-loop makes atomic contacts with SAM or S-adenosylhomocysteine and the 3-position of the catechol inhibitor. This interaction seems to play a critical role in the affinity of the inhibitor and to stabilize the COMT/SAM/Mg2+/nitrocatechol inhibitor complex by fixing the flexible α2α3-loop.


Assuntos
Inibidores de Catecol O-Metiltransferase/farmacologia , Catecol O-Metiltransferase/metabolismo , Catecóis/farmacologia , Pentanonas/farmacologia , Catecol O-Metiltransferase/isolamento & purificação , Inibidores de Catecol O-Metiltransferase/síntese química , Inibidores de Catecol O-Metiltransferase/química , Catecóis/síntese química , Catecóis/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Estrutura Molecular , Pentanonas/síntese química , Pentanonas/química , Relação Estrutura-Atividade
18.
Toxicol Appl Pharmacol ; 395: 114970, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32234388

RESUMO

Synthetic cathinones, such as methylone and pentedrone, are psychoactive derivatives of cathinone, sold in the internet as "plant food" or "bath salts". However, the level at which these compounds and their enantiomers cross the intestinal barrier has not been yet determined. Thus, the present study aimed to analyze the enantioselectivity on the permeability of these drugs through the intestinal barrier by using the Caco-2 cell line, a widely used in vitro model for drug permeability studies. To achieve this goal, an UHPLC-UV method was developed and validated to quantify both synthetic cathinones. The developed UHPLC-UV method revealed high selectivity and a linearity from 1 to 500 µM with correlation coefficients always higher than 0.999. The method has an accuracy that ranged between 89 and 107%, inter-day and intra-day precisions with coefficients of variation below 10%, limits of detection and quantification of 0.31 µM and 0.93 µM for methylone and 0.17 µM and 0.52 µM for pentedrone, respectively. In Caco-2 cells, a differentiated passage of the enantiomers across monolayer was observed for both cathinones. For pentedrone, the difference was observed after the first hour, being R-(-)-pentedrone the most permeable compound. Regarding methylone, the difference was noted after one hour and 30 min, with S-(-)-methylone being the most absorbed enantiomer. In conclusion, a fully validated method was successfully applied for studying the permeability of methylone and pentedrone enantiomers in an in vitro model of human intestine, which allowed to discover, for the first time, the enantioselectivity in drug permeability of this class of drugs.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Absorção Intestinal/fisiologia , Metanfetamina/análogos & derivados , Metilaminas/química , Metilaminas/farmacocinética , Pentanonas/química , Pentanonas/farmacocinética , Alcaloides/química , Células CACO-2 , Humanos , Metanfetamina/química , Metanfetamina/farmacocinética , Permeabilidade , Psicotrópicos , Sensibilidade e Especificidade , Estereoisomerismo , Relação Estrutura-Atividade
20.
Sci Rep ; 10(1): 2725, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066785

RESUMO

Superparamagnetic iron oxide nanoparticles (SPIONs) have been investigated for wide variety of applications. Their unique properties render them highly applicable as MRI contrast agents, in magnetic hyperthermia or targeted drug delivery. SPIONs surface properties affect a whole array of parameters such as: solubility, toxicity, stability, biodistribution etc. Therefore, progress in the field of SPIONs surface functionalization is crucial for further development of therapeutic or diagnostic agents. In this study, SPIONs were synthesized by thermal decomposition of iron (III) acetylacetonate Fe(acac)3 and functionalized with dihexadecyl phosphate (DHP) via phase transfer. Bioactivity of the SPION-DHP was assessed on SW1353 and TCam-2 cancer derived cell lines. The following test were conducted: cytotoxicity and proliferation assay, reactive oxygen species (ROS) assay, SPIONs uptake (via Iron Staining and ICP-MS), expression analysis of the following genes: alkaline phosphatase (ALPL); ferritin light chain (FTL); serine/threonine protein phosphatase 2A (PP2A); protein tyrosine phosphatase non-receptor type 11 (PTPN11); transferrin receptor 1 (TFRC) via RT-qPCR. SPION-DHP nanoparticles were successfully obtained and did not reveal significant cytotoxicity in the range of tested concentrations. ROS generation was elevated, however not correlated with the concentrations. Gene expression profile was slightly altered only in SW1353 cells.


Assuntos
Condrócitos/efeitos dos fármacos , Compostos Férricos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Nanopartículas de Magnetita/química , Organofosfatos/química , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Apoferritinas/genética , Apoferritinas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Condrócitos/citologia , Condrócitos/metabolismo , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Compostos Férricos/química , Humanos , Hidroxibutiratos/química , Pentanonas/química , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores da Transferrina/genética , Receptores da Transferrina/metabolismo , Succímero/química
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