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1.
Foods ; 12(17)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37685219

RESUMO

Rapeseed meal (RSM) is a by-product of rapeseed oil extraction and is a rich source of bioactive compounds, including proteins and antioxidants. This study compared two methods for extracting antioxidants from RSM: conventional ethanol Soxhlet extraction and supercritical CO2 extraction. These procedures were applied to both native RSM and RSM after protein removal to evaluate their bio-compound composition and potential applications. HPLC-DAD, NMR, and GC/MS analyses revealed a rich polyphenolic profile in the extracts, including the presence of sinapic acid. The concentration of sinapic acid varied depending on the extraction method used. The anti-radical activity of the extracts was also analysed using the DPPH assay, which confirmed the potential of RSM as a source of antioxidants for use in cosmetics, food, and pharmaceutical formulations.

2.
Molecules ; 28(15)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37570801

RESUMO

A gold-catalyzed protocol to obtain functionalized 3H-pyrrolo [1,2,3-de] quinoxalines from suitable substituted N-alkynyl indoles has been proposed. The mild reaction conditions were revealed to be compatible with different functional groups, including halogen, alkoxyl, cyano, ketone, and ester, allowing the isolation of title compounds with yields from good to high. A reaction mechanism has been proposed, and theoretical calculations have been provided to rationalize the final step of the hypothesized reaction mechanism. As quinoxaline-containing polycyclic compounds, this class of molecules may represent a valuable template in medicinal chemistry and material science.

3.
Molecules ; 28(13)2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37446580

RESUMO

The dynamic scenario of di-aryls-pyrano-chromenes was investigated using DFT calculations. The symmetry of the chromene scaffold and the presence of two ortho-substituted aryls substituents can generate two syn/anti diastereoisomers and conformational enantiomers with different rotational barriers. The relative conformations and configurations were derived using NOESY-1D experiments. Depending on the energies related to the conformational exchange, the experimental energy barriers were determined through Dynamic NMR, Dynamic HPLC or kinetic studies. The atropisomeric pairs were resolved in the latter scenario, and their absolute configuration was assigned using the ECD/TD-DFT method.


Assuntos
Benzopiranos , Cinética , Conformação Molecular , Espectroscopia de Ressonância Magnética , Teoria da Densidade Funcional
4.
J Org Chem ; 88(11): 6857-6867, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37162477

RESUMO

Experimental results and computational insights explain the key role of transition-metal catalysis/Brønsted acid synergism in the achievement of the sequential regioselective direct heteroarylation/cyclocondensation reactions of ß-(2-aminophenyl)-α,ß-ynones with a variety of electron-rich aromatic heterocyclic/arenes to afford quinoline-(hetero)aromatic hybrids. The first approach to the synthesis of 4-(1H-pyrrol-2-yl)quinolines is described. The effectiveness of various transition metals is compared.

5.
RSC Adv ; 13(15): 10090-10096, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37006346

RESUMO

The synthesis of 2,3-dihydropyrazino[1,2-a]indol-4(1H)-ones from the sequential reaction of amino acid methyl esters with readily available indole-2-ylmethyl acetates is described. The reaction proceeds in situ under basic conditions of highly unstable and reactive 2-alkylideneindolenines followed by Michael-type addition of α-amino acid methyl esters/intramolecular cyclization.

6.
Foods ; 12(8)2023 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-37107387

RESUMO

Fruit seeds belonging to the pomegranate cultivar "Granata" were subjected to extraction and oily component analysis, with the aim of obtaining information about their composition. The presence of conjugated isomers of linolenic acid (CLNA isomers) in the oily phase extracted from the seeds gives a high added value to this part of the fruit, which is too often considered and treated as waste. The separated seeds were subjected to a classic Soxhlet extraction with n-hexane or extraction with supercritical CO2, assisted by ethanol. The resulting oils were evaluated by 1H and 13C-NMR and AP-MALDI-MS techniques. Differences in the triacylglycerols composition, with particular regard to punicic acid and other CLNA content, were studied in depth. Results showed the prevalence of punicic acid in the triacylglycerol mixture up to the 75%, with clear preponderance in the extract by supercritical fluids. Consequently, other CLNA isomers are, altogether, two-fold less represented in the supercritical extract than in the Soxhlet one. The two oily residues were subjected to solid phase extraction (SPE) and to HPLC-DAD analysis for the polyphenolic isolation and characterization. In addition to HPLC analysis, which showed different content and composition, DPPH analysis to evaluate the antiradical potential showed that the extract obtained with supercritical CO2 was much more active.

7.
Int J Mol Sci ; 23(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35742969

RESUMO

Amine oxidases are enzymes belonging to the class of oxidoreductases that are widespread, from bacteria to humans. The amine oxidase from Lathyrus cicera has recently appeared in the landscape of biocatalysis, showing good potential in the green synthesis of aldehydes. This enzyme catalyzes the oxidative deamination of a wide range of primary amines into the corresponding aldehydes but its use as a biocatalyst is challenging due to the possible inactivation that might occur at high product concentrations. Here, we show that the enzyme's performance can be greatly improved by immobilization on solid supports. The best results are achieved using amino-functionalized magnetic microparticles: the immobilized enzyme retains its activity, greatly improves its thermostability (4 h at 75 °C), and can be recycled up to 8 times with a set of aromatic ethylamines. After the last reaction cycle, the overall conversion is about 90% for all tested substrates, with an aldehyde production ranging between 100 and 270 mg depending on the substrate used. As a proof concept, one of the aldehydes thus produced was successfully used for the biomimetic synthesis of a non-natural benzylisoquinoline alkaloid.


Assuntos
Lathyrus , Aldeídos , Aminas , Biocatálise , Enzimas Imobilizadas/metabolismo , Humanos , Lathyrus/metabolismo , Fenômenos Magnéticos , Monoaminoxidase/metabolismo , Oxirredutases/metabolismo
8.
Org Biomol Chem ; 20(15): 3160-3173, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35343991

RESUMO

The functionalized 3,4-dihydroquinolin-2-one nucleus has been assembled in good to high yields through the sequential reaction of readily available N-Ts-o-aminobenzyl alcohols with 5-substituted Meldrum's acid derivatives under mild basic conditions. Highly diastereoselective synthesis of 3-substituted-4-phenyl-1-tosyl-3,4-dihydroquinolin-2(1H)-ones was accomplished from N-(2-(hydroxy(phenyl)methyl)phenyl)-4-methylbenzenesulfonamide under the same reaction conditions. Regarding the reaction mechanism, we hypothesized that the formation of dihydroquinolones proceeds through the in situ generation of aza-o-QMs followed by conjugate addition of enolate/cyclization/elimination of acetone and CO2.


Assuntos
Dioxanos , Ciclização
9.
Foods ; 11(2)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35053885

RESUMO

The aim of this work was to develop innovative and sustainable extraction, concentration, and purification technologies aimed to recover target substances from corn oil, obtained as side stream product of biomass refineries. Residues of bioactive compounds such as carotenoids, phytosterols, tocopherols, and polyphenols could be extracted from this matrix and applied as ingredients for food and feeds, nutraceuticals, pharmaceuticals, and cosmetic products. These molecules are well known for their antioxidant and antiradical capacity, besides other specific biological activities, generically involved in the prevention of chronic and degenerative diseases. The project involved the development of methods for the selective extraction of these minor components, using as suitable extraction technique solid phase extraction. All the extracted and purified fractions were evaluated by NMR spectroscopic analyses and UV-Vis spectrophotometric techniques and characterized by quali-quantitative HPLC analyses. TPC (total phenolic content) and TFC (total flavonoid content) were also determined. DPPH and ABTS radical were used to evaluate radical quenching abilities. Acetylcholinesterase (AChE), amylase, glucosidase, and tyrosinase were selected as enzymes in the enzyme inhibitory assays. The obtained results showed the presence of a complex group of interesting molecules with strong potential in market applications according to circular economy principles.

10.
Molecules ; 28(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36615493

RESUMO

The gold-catalyzed cyclization of 2,2-bis(3-arylprop-2-yn1-yl)malonic acid has been proposed as an efficient approach to substituted 3,8-dibenzyl-2,7-dioxaspiro[4.4]nonane-1,6-diones. The reaction proceeds smoothly in mild reaction conditions to give the desired products in quantitative yields in the presence of variously substituted starting materials. In addition, the synthesis of γ-arylidene spirobislactone bearing different substituents on the two aromatic rings has been achieved. This kind of compound could be of great interest in pharmaceutical science given the widespread presence of this scaffold in bioactive natural and synthetic products.


Assuntos
Ouro , Estrutura Molecular , Catálise , Ciclização
11.
Molecules ; 26(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199620

RESUMO

An alternative Au(I)-catalyzed synthetic route to functionalized 1,2-dihydroquinolines is reported. This novel approach is based on the use of N-ethoxycarbonyl protected-N-propargylanilines as building blocks that rapidly undergo the IMHA reaction affording the 6-endo cyclization product in good to high yields. In the presence of N-ethoxycarbonyl-N-propargyl-meta-substituted anilines, the regiodivergent cyclization at the ortho-/para-position is achieved by the means of catalyst fine tuning.

12.
J Nanobiotechnology ; 19(1): 172, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34107976

RESUMO

BACKGROUND: In recent years, the use of ferritins as nano-vehicles for drug delivery is taking center stage. Compared to other similar nanocarriers, Archaeoglobus fulgidus ferritin is particularly interesting due to its unique ability to assemble-disassemble under very mild conditions. Recently this ferritin was engineered to get a chimeric protein targeted to human CD71 receptor, typically overexpressed in cancer cells. RESULTS: Archaeoglobus fulgidus chimeric ferritin was used to generate a self-assembling hybrid nanoparticle hosting an aminic dendrimer together with a small nucleic acid. The positively charged dendrimer can indeed establish electrostatic interactions with the chimeric ferritin internal surface, allowing the formation of a protein-dendrimer binary system. The 4 large triangular openings on the ferritin shell represent a gate for negatively charged small RNAs, which access the internal cavity attracted by the dense positive charge of the dendrimer. This ternary protein-dendrimer-RNA system is efficiently uptaken by acute myeloid leukemia cells, typically difficult to transfect. As a proof of concept, we used a microRNA whose cellular delivery and induced phenotypic effects can be easily detected. In this article we have demonstrated that this hybrid nanoparticle successfully delivers a pre-miRNA to leukemia cells. Once delivered, the nucleic acid is released into the cytosol and processed to mature miRNA, thus eliciting phenotypic effects and morphological changes similar to the initial stages of granulocyte differentiation. CONCLUSION: The results here presented pave the way for the design of a new family of protein-based transfecting agents that can specifically target a wide range of diseased cells.


Assuntos
Dendrímeros/química , Sistemas de Liberação de Medicamentos/métodos , Ferritinas/química , Leucemia Mieloide/tratamento farmacológico , Nanopartículas/química , Ácidos Nucleicos/química , Antígenos CD , Archaeoglobus fulgidus/genética , Archaeoglobus fulgidus/metabolismo , Linhagem Celular Tumoral , Ferritinas/genética , Humanos , MicroRNAs/química , MicroRNAs/farmacologia , Receptores da Transferrina
13.
Org Biomol Chem ; 19(23): 5177-5190, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34042150

RESUMO

A divergent domino condensation/biannulation reaction of ß-(2-aminophenyl) α,ß-ynones with 1,3-dicarbonyls to construct a polycyclic 4H-pyrano[3,4-c]quinoline core has been developed. The p-TsOH·H2O catalyzed reaction of ß-(2-aminophenyl) α,ß-ynones with ß-ketoesters in ethanol proceeds with good to excellent yields to provide a simple and effective method for the synthesis of functionalized 4H-pyrano[3,4-c]quinolinones. Further elaboration of these latter derivatives with an excess of 20% NH4OH in EtOH at 50 °C helps achieve the synthesis of the perlodinine analogues benzo[c][2,7]naphthyridin-4(3H)-one derivatives in high yields. Moreover, the p-TsOH·H2O mediated reaction of ß-(2-aminophenyl) α,ß-ynones with ß-di-ketones leads to the formation of a variety of structurally diverse 4H-pyrano[3,4-c]quinoline polycyclic ketals by the incorporation of an alcohol solvent molecule in a cascade fashion.

14.
Org Biomol Chem ; 19(2): 421-438, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33315039

RESUMO

This study describes diversity-oriented synthesis of 2,2,3-substituted-2,3-dihydroquinolin-4(1H)-ones vs. functionalised quinoline or N-alkenylindole derivatives through Brønsted acid mediated or Lewis acid catalyzed sequential reactions of 2-alkynylanilines with ketones. In particular, a series of challenging quinolin-4-one derivatives are prepared with good functional group tolerance in an atom-economical fashion by using p-toluenesulfonic acid monohydrate as a promoter of the reaction of ketones with 2-alkynylanilines in EtOH at reflux, while the same starting materials give the corresponding 4-substituted quinolines in toluene at 110 °C both in the presence of p-toluenesulfonic acid monohydrate as the promoter and FeCl3 as the catalyst. The divergent formation of N-alkenylindole derivatives occurs by switching to the use of ZnBr2 as the catalyst under the same reaction conditions. Conversely, only 4-methylsubstituted quinoline derivatives were isolated by reacting 2-ethynylanilines and/or 2-trimethylsylilanilines with ketones in all examined cases.

15.
Molecules ; 25(9)2020 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-32357533

RESUMO

Fully ripe fruits and mature leaves of Elaeagnus angustifolia were harvested and analyzed by means of analytical and biological tests to better comprehend the chemical composition and therapeutic/nutraceutical potential of this plant. Fruits and leaves were dried and the obtained powders were analyzed to study their color character and (via headspace gas chromatography) describe the chemical profile. Subsequently, they were submitted to a chloroform-methanol extraction, to a hydroalcoholic extraction procedure assisted or not by microwaves, and to an extraction with supercritical CO2, assisted or not by ethanol as the co-solvent, to detect the polyphenolic and the volatile content. The resulting extracts were evaluated in terms of chlorophyll and carotenoid content, polyphenolic content, volatile fraction, total phenolic content, total flavonoid content, antioxidant activity, radical scavenging activity, and enzymatic inhibition activity. The results confirmed the correlation between the chemical composition and the high antioxidant potential of leaf extracts compared to the fruit extracts in terms of the phenolic and pigment content. A promising effect against tyrosinase emerged for all the extracts, suggesting a therapeutic/nutraceutical use for this plant. Conversely, the volatile content from both natural matrices was similar.


Assuntos
Antioxidantes/análise , Carotenoides/análise , Elaeagnaceae/química , Flavonoides/análise , Frutas/química , Extratos Vegetais/análise , Folhas de Planta/química , Polifenóis/análise , Antioxidantes/química , Carotenoides/química , Clorofórmio/química , Clorofila/análise , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Cor , Flavonoides/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Metanol/química , Micro-Ondas , Monofenol Mono-Oxigenase/antagonistas & inibidores , Fenóis/análise , Fenóis/química , Extratos Vegetais/química , Polifenóis/química , Pós , Solventes/química
16.
RSC Adv ; 11(2): 909-917, 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35423668

RESUMO

The palladium-catalyzed benzylic-like nucleophilic substitution of benzofuran-2-ylmethyl acetate with N, S, O and C soft nucleophiles has been investigated. The success of the reaction is dramatically influenced by the choice of catalytic system: with nitrogen based nucleophiles the reaction works well with Pd2(dba)3/dppf, while with sulfur, oxygen and carbo-nucleophiles [Pd(η3-C3H5)Cl]2/XPhos is more efficient. The regiochemical outcome shows that the nucleophilic substitution occurs only on the benzylic position of the η3-(benzofuryl)methyl complex. The high to excellent yields and the simplicity of the experimental procedure make this protocol a versatile synthetic tool for the preparation of 2-substituted benzo[b]furans.

17.
Org Biomol Chem ; 17(47): 10065-10072, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31748762

RESUMO

Regioselective access to 10-substituted-2H,8H-pyrano[2,3-f]chromen-2-ones through the gold-catalyzed intramolecular hydroarylation of readily available 7-(prop-2-yn-1-yloxy)-2H-chromen-2-one derivatives at their C-8 congested position was investigated by tuning the electronic and steric properties of the ligand on the gold complex. On the other hand, the combination of the JohnPhosAu(MeCN)SbF6 catalyzed intramolecular hydroarylation of 8-iodo-7-(prop-2-yn-1-yloxy)-2H-chromen-2-one derivatives followed by selective palladium/formate C-I reduction allows for the exclusive formation of 2H,8H-pyrano[3,2-g]chromen-2-one regioisomers. The development of these two protocols provides versatile synthetic tools required for exploring the biological activities of these new pyranocoumarin derivatives.

18.
ACS Med Chem Lett ; 10(4): 639-643, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30996810

RESUMO

Based on hit-likeness and chemical diversity, a number of chalcones and chalcone-mimetic compounds were selected as putative Notch inhibitors. The evaluation of the antiproliferative effect combined with the inhibition of Notch1 expression in KOPTK1 cell line identified compound 18, featuring a tetrahydronaphthalene-based scaffold, as a new promising Notch-blocking agent.

19.
Eur J Med Chem ; 161: 277-291, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30366254

RESUMO

Despite the recent reductions in the global burden of malaria, this disease remains a devastating cause of death in tropical and subtropical regions. As there is no broadly effective vaccine for malaria, prevention and treatment still rely on chemotherapy. Unfortunately, emerging resistance to the gold standard artemisinin combination therapies means that new drugs with novel modes of action are urgently needed. In this context, Plasmodium histone modifying enzymes have emerged as potential drug targets, prompting us to develop and optimize compounds directed against such epigenetic targets. A panel of 51 compounds designed to target different epigenetic enzymes were screened for activity against Plasmodium falciparum parasites. Based on in vitro activity against drug susceptible and drug-resistant P. falciparum lines, selectivity index criterion and favorable pharmacokinetic properties, four compounds, one HDAC inhibitor (1) and three DNMT inhibitors (37, 43 and 45), were selected for preclinical studies in a mouse model of malaria. In vivo data showed that 37, 43 and 45 exhibited oral efficacy in the mouse model of Plasmodium berghei infection. These compounds represent promising starting points for the development of novel antimalarial drugs.


Assuntos
Antimaláricos/farmacologia , Plasmodium berghei/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Quinazolinas/farmacologia , Animais , Antimaláricos/síntese química , Antimaláricos/química , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Fibroblastos/microbiologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Conformação Molecular , Testes de Sensibilidade Parasitária , Plasmodium falciparum/crescimento & desenvolvimento , Quinazolinas/síntese química , Quinazolinas/química , Relação Estrutura-Atividade
20.
Org Biomol Chem ; 17(3): 527-532, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30569043

RESUMO

The gold-catalyzed hydroamination of 2-(arylethynyl)pyridines with anilines affords stereoselectively Z-enamine products with excellent regioselectivity. The reaction proceeds with moderate to excellent yields and accommodates a diverse range of functional groups on alkynes (ether, bromo, trifluoromethyl, acetyl, and carbomethoxy) and anilines (ether, bromo, chloro, and carbethoxy). The stereochemistry of the obtained enamines is complementary to that reported in previous studies. A plausible explanation for the observed selectivity was attained by means of NMR experiments.

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