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1.
Arch Pharm (Weinheim) ; 354(1): e2000116, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33015829

RESUMO

In continuation of our previous work on cancer and inflammation, 15 novel pyrazole-pyrazoline hybrids (WSPP1-15) were synthesized and fully characterized. The formation of the pyrazoline ring was confirmed by the appearance of three doublets of doublets in 1 H nuclear magnetic resonance spectra exhibiting an AMX pattern for three protons (HA , HM , and HX ) of the pyrazoline ring. All the synthesized compounds were screened for their in vitro anticancer activity against five cell lines, that is, MCF-7, A549, SiHa, COLO205, and HepG2 cells, using the MTT growth inhibition assay. 5-Fluorouracil was taken as the positive control in the study. It was observed that, among them, WSPP11 was found to be active against A549, SiHa, COLO205, and HepG2 cells, with IC50 values of 4.94, 4.54, 4.86, and 2.09 µM. All the derivatives were also evaluated for their cytotoxicity against HaCaT cells. WSPP11 was also found to be nontoxic against normal cells (cell line HaCaT), with an IC50 value of more than 50 µM. The derivatives were also evaluated for their in vitro anti-inflammatory activity by the protein (egg albumin) denaturation assay and the red blood cell membrane stabilizing assay, using diclofenac sodium and celecoxib as standard. Compounds that showed significant anticancer and anti-inflammatory activities were further studied for COX-2 inhibition. The manifestation of a higher COX-2 selectivity index of WSPP11 as compared with other derivatives and an in vitro anticancer activity against four cell lines further established that compounds that were more selective toward COX-2 also exhibited a better spectrum of activity against various cancer cell lines.


Assuntos
Antineoplásicos/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Neoplasias/tratamento farmacológico , Pirazóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/química , Desenho de Fármacos , Fluoruracila/farmacologia , Humanos , Concentração Inibidora 50 , Neoplasias/patologia , Pirazóis/síntese química , Pirazóis/química , Relação Estrutura-Atividade
2.
Arch Pharm (Weinheim) ; 353(5): e1900333, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32115728

RESUMO

In continuation of our previous work on anticancer and anti-inflammatory agents, a series of 22 novel methylene-bearing sulfur-containing cyanopyrimidine derivatives was synthesized by Biginelli condensation reaction, which was followed by nucleophilic substitution of the chloro group with secondary or tertiary amines. Structural confirmation of these derivatives was attained through different spectral techniques. Then, anticancer evaluation of these compounds was done at the National Cancer Institute. Compounds 4g, 4j, 4k, and 4v demonstrated appreciable results against different cell lines. Among the synthesized compounds, 4g (NSC: 795475) exhibited a growth inhibition (GI) of 81.34% against the NCI-H460 lung cancer cell line, 72.64% against the ACHN renal cancer cell line, and 112.17% against the OVCAR-4 ovarian cancer cell line. Compound 4j (NSC: 795746) was active against U-251 CNS cancer, OVCAR-4 ovarian cancer, and 786-0 and ACHN renal cancer cell lines, with GI of 78.84%, 150.38%, 75.64%, and 86.45%, respectively. The literature supporting the association between cancer and underlying inflammation prompted us to evaluate the four compounds, 4g, 4j, 4k, and 4v, with appreciable anticancer activity for their in vitro anti-inflammatory activity. Cyclooxygenase (COX)-2 inhibition studies were also performed to study the molecular target. To validate the target study, molecular docking studies in the ligand-binding domain of COX-2 (PDB ID: 1CX2) were also performed. Compounds 4g, 4j, and 4k did not show cytotoxicity on RAW 264.7 cells up to 10 µM concentration; however, compound 4v showed cytotoxic effects at 10 µM concentration.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Metano/farmacologia , Pirimidinas/farmacologia , Enxofre/farmacologia , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Metano/química , Camundongos , Modelos Moleculares , Estrutura Molecular , Pirimidinas/química , Células RAW 264.7 , Relação Estrutura-Atividade , Enxofre/química
3.
Anal Chem ; 91(21): 14085-14092, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31585033

RESUMO

Mycotoxins posit serious threats to human and animal health, and numerous efforts have been performed to detect the multiple toxins by a single diagnostic approach. To best of our knowledge, for the first time, we synthesized an aptamer induced "turn on" fluorescence resonance energy transfer (FRET) biosensor using dual-color gold nanoclusters (AuNCs), l-proline, and BSA synthesized AuNCs (Lp-AuNCs and BSA-AuNCs), with WS2 nanosheet for simultaneous recognition of aflatoxinB1 (AFB1) and zearalenone (ZEN) by single excitation. Here, AFB1 aptamer stabilized blue-emitting AuNCs (AFB1-apt-Lp-AuNCs) (at 442 nm) and ZEN aptamer functionalized with red-colored AuNCs (ZEN-apt-BSA-AuNCs) (at 650 nm) were employed as an energy donor and WS2 nanosheet as a fluorescence quencher. With the addition of AFB1 and ZEN, the change in fluorescence intensity (F.I) was recorded at 442 and 650 nm and can be used for simultaneous recognition with a detection limit of 0.34 pg mL-1 (R2 = 0.9931) and 0.53 pg mL-1 (R2 = 0.9934), respectively. Most importantly, the semiquantitative determination of AFB1 and ZEN can also be realized through photovisualization. The current approach paves a new way to develop sensitive, selective, and convenient metal nanocluster-based fluorescent "switch-on" probes with potential applications in multipurpose biosensing.


Assuntos
Aflatoxina B1/análise , Cor , Transferência Ressonante de Energia de Fluorescência , Ouro/química , Nanopartículas/química , Zearalenona/análise , Aptâmeros de Nucleotídeos/química , Espectrometria de Fluorescência , Sulfetos/química , Compostos de Tungstênio/química , Zea mays/química
4.
Bioorg Chem ; 87: 667-678, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30953886

RESUMO

Meagre and suboptimal therapeutic response along with the side effect profile associated with the existing anticancer therapy have necessitated the development of new therapeutic modalities to curb this disease. Bearing in mind the current scenario, a series of 1,2,3-triazole linked 3-(1,3-diphenyl-1H-pyrazol-4-yl)acrylates was synthesized following a multi-step reaction scheme. Initial screening for anticancer potential was done by in vitro sulforhodamine B assay against four human cancer cell lines- MCF-7 (breast), A549 (Lung) and HCT-116 and HT-29 (Colon). On evaluation, several compounds showed promising growth inhibition against all the cell lines, particularly compounds 6e, 6f and 6n. Among them, compound 6f displayed IC50 values of 1.962, 3.597, 1.764 and 4.496 µM against A549, HCT-116, MCF-7 and HT-29 cell lines respectively. Furthermore, the apoptosis inducing potential of the compounds was determined by Hoechst staining and DNA fragmentation assay. Colony formation inhibition assay was also carried out to determine the long term cytotoxic potential of the molecules. Moreover, compounds 6e, 6f and 6n were also evaluated for anti-inflammatory activity by protein albumin denaturation assay and red blood cell membrane stabilizing assay.


Assuntos
Acrilatos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Triazóis/farmacologia , Acrilatos/química , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Antineoplásicos/síntese química , Antineoplásicos/química , Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Eritrócitos/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Ovalbumina/metabolismo , Desnaturação Proteica/efeitos dos fármacos , Soroalbumina Bovina/metabolismo , Relação Estrutura-Atividade , Triazóis/química , Células Tumorais Cultivadas
5.
Mikrochim Acta ; 186(8): 575, 2019 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-31342182

RESUMO

A "turn on" time-resolved fluorometric aptasensor is described for the simultaneous detection of zearalenone (ZEN), trichothecenes A (T-2), and aflatoxin B1 (AFB1). Multicolor-emissive nanoparticles doped with lanthanide ions (Dy3+, Tb3+, Eu3+) were functionalized with respective aptamers and applied as a bioprobe, and tungsten disulfide (WS2) nanosheets are used as a quencher of time-resolved fluorescence. The assay exploits the quenching efficiency of WS2 and the interactions between WS2 and the respective DNA aptamers. The simultaneous recognition of the three mycotoxins can be performed in a single solution. In the absence of targets, WS2 is easily adsorbed by the mixed bioprobes via van der Waals forces between nucleobases and the WS2 basal plane. This brings the bioprobe and WS2 into close proximity and results in quenched fluorescence. In the presence of targets, the fluorescence of the bioprobes is restored because the analytes react with DNA probe and modify their molecular conformation to weaken the interaction between the DNAs and WS2. Under the optimum conditions and at an excitation wavelength of 273 nm, the time-resolved fluorescence intensities (peaking at 488, 544 and 618 nm and corresponding to emissions of Dy3+, Tb3+ and Eu3+) were used to quantify ZEN, T-2 and AFB1, respectively, with detection limits of 0.51, 0.33 and 0.40 pg mL-1 and a linear range from 0.001 to 100 ng mL-1. The three mycotoxins can be detected simultaneously without mutual interference. The assay was applied to the quantification of ZEN, T-2 and AFB1 in (spiked) maize samples. This homogeneous aptamer based assay can be performed within 1 h. Conceivably, it can become an alternative to other heterogeneous methods such as the respective enzyme-linked immunosorbent assays. Graphical abstract Schematic presentation of an aptasensor for simultaneous detection of zearalenone, trichothecenes A and aflatoxin B1 using aptamer modified time-resolved fluorescence nanoparticles as signalling probes and tungsten disulfide as the quencher. This assay shows lower detection limit and requires no washing steps.


Assuntos
Aflatoxina B1/análise , Aptâmeros de Nucleotídeos , Fluorometria/métodos , Micotoxinas/análise , Tricotecenos/análise , Zearalenona/análise , Fluorometria/normas , Contaminação de Alimentos/análise , Limite de Detecção , Compostos de Tungstênio/química , Zea mays
6.
Angew Chem Int Ed Engl ; 58(36): 12558-12562, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31265208

RESUMO

Hydrogen borrowing catalysis serves as a powerful alternative to enolate alkylation, enabling the direct coupling of ketones with unactivated alcohols. However, to date, methods that enable control over the absolute stereochemical outcome of such a process have remained elusive. Here we report a catalytic asymmetric method for the synthesis of enantioenriched cyclohexanes from 1,5-diols via hydrogen borrowing catalysis. This reaction is mediated by the addition of a chiral iridium(I) complex, which is able to impart high levels of enantioselectivity upon the process. A series of enantioenriched cyclohexanes have been prepared and the mode of enantioinduction has been probed by a combination of experimental and DFT studies.

7.
J Am Chem Soc ; 140(38): 11916-11920, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30212192

RESUMO

An iridium catalyzed method for the synthesis of functionalized cyclohexanes from methyl ketones and 1,5-diols is described. This process operates by two sequential hydrogen borrowing reactions, providing direct access to multisubstituted cyclic products with high levels of stereocontrol. This methodology represents a novel (5 + 1) strategy for the stereoselective construction of the cyclohexane core.

8.
Bioorg Chem ; 77: 106-124, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29353728

RESUMO

Depravity of malaria in terms of morbidity and mortality in human beings makes it a major health issue in tropical and subtropical areas of the globe. Drug counterfeiting and non-adherence to the treatment regimen have significantly contributed to development and spread of multidrug resistance that has highlighted the need for development of novel and more efficient antimalarial drugs. Complexity associated with cancer disease and prevalence of diversified cell populations vindicates highly specific treatment options for treatment of cancer. Resistance to these anticancer agents has posed a great hindrance in successful treatment of cancer. Pondering this ongoing situation, it was speculated to develop novel compounds targeting malaria and cancer. Moving on the same aisle, we synthesized pyrazole acrylic acid based oxadiazole and amide derivatives using multi-step reaction pathways (6a-x; 6a'-h'). Schizont maturation inhibition assay was employed to determine antimalarial potential. Compound 6v emerged as the most potent antimalarial agent targeting falcipain-2 enzyme. Anticancer activity was done using sulforhodamine B assay. Compounds 6b' and 6g' demonstrated promising results against all the tested cell lines. Further, Microscopic view clearly indicated formation of apoptotic bodies, chromatin condensation, shrinkage of cells and bleb formation. Validation of the results was achieved using molecular docking studies. From the obtained results, it was observed that cyclization (oxadiazole) favored antimalarial activity while non-cyclized compounds (amides) emerged as better anticancer agents.


Assuntos
Acrilatos/farmacologia , Amidas/farmacologia , Antimaláricos/farmacologia , Antineoplásicos/farmacologia , Oxidiazóis/farmacologia , Pirazóis/farmacologia , Acrilatos/química , Amidas/síntese química , Amidas/química , Antimaláricos/síntese química , Antimaláricos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Oxidiazóis/síntese química , Oxidiazóis/química , Testes de Sensibilidade Parasitária , Plasmodium falciparum/efeitos dos fármacos , Pirazóis/química , Relação Estrutura-Atividade
9.
Toxicol Mech Methods ; 28(1): 45-54, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28715929

RESUMO

Glucocorticoids are known to have vital effects on metabolism, behavior and immunity. Any sort of impairment in their synthesis may lead to the generation of numerous ill health effects. Different environmental toxicants, including bisphenols and their analogs pose deleterious effect on the biosynthesis of glucocorticoids, thereby leading to endocrine disruption. In order to assess the effect of these environmental toxicants on gluocorticoid biosynthetic pathway, an in silico study was performed. This involved molecular docking studies of 18 ligands with the selected participating enzymes of the pathway. These enzymes were CYP11A1, CYP11B2, CYP19A1, CYP17A1, 3α/20ß-HSD, 3ß/17ß-HSD and CYP21A2. Comparison of their binding affinity was made with the known inhibitors of these enzymes. In case of CYP11A1, Bisphenol M (BP M) had the lowest docking score (D score) of -8.699 kCal/mol, and was better than that of the standard, Metyrapone. Bisphenol PH (BP PH) was found to have significant affinity with CYP11B2. In case CYP19A1, results were found to be comparable with the standards, Exemestane and Letrozole. BP PH elicited better results than the standard Abiraterone acetate against CYP17A1. BP M had a D score of -7.759 against 3α/20ß-HSD, again better results than the standard, Trilostane. Upon molecular docking of BP PH against CYP21A2, it was seen that amongst all the analogs, it had maximum interactions along with the lowest D score. From all the above instances mentioned, it is quite evident that certain BPA analogs have more potential to modulate the enzymes involved in comparison to the known inhibitors.


Assuntos
Compostos Benzidrílicos/toxicidade , Inibidores das Enzimas do Citocromo P-450/toxicidade , Sistema Enzimático do Citocromo P-450/metabolismo , Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Glucocorticoides/biossíntese , Hidroxiesteroide Desidrogenases/antagonistas & inibidores , Simulação de Acoplamento Molecular , Fenóis/toxicidade , Compostos Benzidrílicos/química , Compostos Benzidrílicos/metabolismo , Sítios de Ligação , Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/química , Disruptores Endócrinos/química , Disruptores Endócrinos/metabolismo , Poluentes Ambientais/química , Poluentes Ambientais/metabolismo , Hidroxiesteroide Desidrogenases/química , Hidroxiesteroide Desidrogenases/metabolismo , Ligantes , Fenóis/química , Fenóis/metabolismo , Ligação Proteica , Conformação Proteica , Medição de Risco , Relação Estrutura-Atividade
10.
J Am Chem Soc ; 139(7): 2577-2580, 2017 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-28177613

RESUMO

A hydrogen borrowing reaction employing secondary alcohols and Ph* (Me5C6) ketones to give ß-branched carbonyl products is described (21 examples). This new C-C bond forming process requires low loadings of [Cp*IrCl2]2, relatively low temperatures, and up to 2.0 equiv of the secondary alcohol. Substrate-induced diastereoselectivity was observed, and this represents the first example of a diastereoselective enolate hydrogen borrowing alkylation. By utilizing the Ph* group, the ß-branched products could be straightforwardly cleaved to the corresponding esters or amides using a retro-Friedel-Crafts reaction. Finally, this protocol was applied to the synthesis of fragrance compound (±)-3-methyl-5-phenylpentanol.

11.
J Mol Recognit ; 30(12)2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28639323

RESUMO

Dioxins and dioxin-like compounds (DLCs) are known to cause endocrine disruption in humans and animals. Being lipophilic xenobiotic chemicals, they can be easily absorbed into the biological system from the surrounding environments, thereby causing various health dysfunctions. In the present study, a total of 100 dioxins and DLCs were taken, and their binding pattern was assessed with the xenosensors pregnane X receptor (PXR) and constitutive androstane receptor (CAR) in comparison with the corresponding known inhibitors and a well-studied endocrine disrupting xenobiotic, bisphenol A (BPA). The nuclear receptors CAR and PXR are known to play a significant role in handling potential toxins by coordinating cellular transport and metabolic functions of the same. Among different endocrine-disrupting chemicals used in the present study, DLCs (PCDFs and PCBs) elicited better interactions in comparison with the parent dioxin (polychlorinated dibenzodioxins) compounds. On comparing D scores of all the compounds against both the receptors, PCDF 8-hydroxy-3,4-dichlorodibenzofuran (8-OH-DCDF) and PCB tetrachlorobenzyltoluene (TCBT) exhibited significant molecular interactions against PXR (-7.633 kcal mol-1 ) and CAR (-8.389 kcal mol-1 ), respectively. Predominant interactions were found to be H-bonding, π-π stacking, hydrophobic, polar, and van der Waals. By contrast, BPA and some natural ligands tested in this study showed lower binding affinities with these receptors than certain DLCs reported herein, ie, certain DLCs might be more toxic than the proven toxic agent, BPA. Such studies play a pivotal role in the risk assessment of exposure to dioxins and DLCs on human health.


Assuntos
Simulação por Computador , Dioxinas e Compostos Semelhantes a Dioxinas/química , Dioxinas e Compostos Semelhantes a Dioxinas/metabolismo , Receptores Citoplasmáticos e Nucleares/química , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Medição de Risco , Biocatálise , Receptor Constitutivo de Androstano , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Simulação de Acoplamento Molecular , Receptor de Pregnano X , Receptores de Esteroides/química , Reprodutibilidade dos Testes
12.
Biotechnol Lett ; 39(5): 647-666, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28185031

RESUMO

Plant proteinase inhibitor-II (PI-II) proteins are one of the promising defensive proteins that helped the plants to resist against different kinds of unfavorable conditions. Different roles for PI-II have been suggested such as regulation of endogenous proteases, modulation of plant growth and developmental processes and mediating stress responses. The basic knowledge on genetic and molecular diversity of these proteins has provided significant insight into their gene structure and evolutionary relationships in various members of this family. Phylogenetic comparisons of these family genes in different plants suggested that the high rate of retention of gene duplication and inhibitory domain multiplication may have resulted in the expansion and functional diversification of these proteins. Currently, a large number of transgenic plants expressing PI-II genes are being developed for enhancing the defensive capabilities against insects, bacteria and pathogenic fungi. Much emphasis is yet to be given to exploit this ever expanding repertoire of genes for improving abiotic stress resistance in transgenic crops. This review presents an overview about the current knowledge on PI-II family genes, their multifunctional role in plant defense and physiology with their potential applications in biotechnology.


Assuntos
Proteínas de Plantas , Biotecnologia , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
13.
Toxicol Mech Methods ; 27(2): 151-163, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27997270

RESUMO

Dioxins and dioxin-like compounds (DLCs) are the ones with poor water solubility and low volatility, resistant to physical, chemical and biological processes, persistent in the environment even under extreme conditions. Due to lipophilic nature, they get adhered to the fatty material and concentrate through biomagnification and bioaccumulation, thereby easily getting incorporated into food chains, paving the way to endocrine disruption via modulation of various human receptors. This in turn leads to certain adverse health effects. In the present study, a total of 100 dioxins and DLCs were taken and their binding pattern was assessed with the ketosteroid receptors, i.e. androgen (hAR), glucocorticoid (hGR), progesterone (hPR) and mineralocorticoid (hMR) in comparison to the corresponding natural steroids and a known endocrine disrupting xenobiotic, Bisphenol A (BPA). Most of the DLCs, particularly those bearing hydroxyl (-OH) group showed considerable affinities with ketosteroid receptors. On comparing D scores of all the dioxins and DLCs against all four receptors, compound 8-hydroxy-3,4-dichlorodibenzofuran(8-OH-DCDF) exhibited least D score of -9.549 kcal mol-1 against hAR. 3,8-Dihydroxy-2-chlorodibenzofuran(3,8-DiOH-CDF), 4'-hydroxy-2,3,4,5-tetrachlorobiphenyl (4'-OH-TCB) and 4-hydroxy-2,2',5'-trichlorobiphenyl(4-OH-TCB) also showed comparable molecular interactions with the ketosteroid receptors. These interactions mainly include H-bonding, π-π stacking, hydrophobic, polar and van der Waals' interactions. In contrast, BPA and some natural ligands tested in this study showed lower binding affinities with these receptors than certain DLCs reported herein, i.e. certain DLCs might be more toxic than the proven toxic agent, BPA. Such studies play a pivotal role in the risk assessment of exposure to dioxins and DLCs on human health.


Assuntos
Dioxinas/química , Disruptores Endócrinos/química , Cetosteroides/química , Receptores de Esteroides/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Reprodutibilidade dos Testes , Medição de Risco
14.
Angew Chem Int Ed Engl ; 56(47): 14883-14887, 2017 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-28926175

RESUMO

Catalytic oxidative cyclisation reactions have been employed for the synthesis of the E and F rings of the complex natural product target pectenotoxin 4. The choice of metal catalyst (cobalt- or osmium-based) allowed for the formation of THF rings with either trans or cis stereoselectivity. Fragment union using a modified Julia reaction then enabled the synthesis of an advanced synthetic intermediate containing the EF and G rings of the target.

15.
J Am Chem Soc ; 137(50): 15664-7, 2015 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-26654947

RESUMO

The application of an iridium-catalyzed hydrogen borrowing process to enable the formation of α-branched ketones with higher alcohols is described. In order to facilitate this reaction, ortho-disubstituted phenyl and cyclopropyl ketones were recognized as crucial structural motifs for C-C bond formation. Having optimized the key catalysis step, the ortho-disubstituted phenyl products could be further manipulated by a retro-Friedel-Crafts acylation reaction to produce synthetically useful carboxylic acid derivatives. In contrast, the cyclopropyl ketones underwent homoconjugate addition with several nucleophiles to provide further functionalized branched ketone products.

16.
Pharm Nanotechnol ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38778594

RESUMO

Cancer nanomedicine has the potential to take advantage of the multifunctionality and diverse biological activity of nanostructures based on biomolecules. Novel drug delivery vehicles can be designed by programming the supramolecular features of biomolecules to achieve multiple therapeutic goals at once, including efficient in vivo transport and targeted drug administration. Proteins, peptides, nucleic acids, and polysaccharides can all be engineered into multipurpose nanomedicines. Even while numerous cancer medications reduce mortality, they are still insufficient. Early cancer cell detection and high-specificity therapeutic administration optimise treatment and prevent toxicity. Nanotechnology is improving cancer diagnosis and treatment due to increased systemic toxicity and refractoriness with current methods. Nanotechnology-based immunotherapeutic drugs have reduced cancer cell invasiveness while protecting healthy cells in several cancer types. Carbon nanotubes, polymeric micelles, and liposomes improve cancer medication pharmacokinetics and pharmacodynamics. Nanomedicines' use in patient care and promising nanotechnology-based cancer interventions have been covered in this article. Nanomaterials used in treating cancer have been discussed. Additionally, nanomaterial obstacles that hinder their applicability and clinical translation in certain cancer types are addressed.

17.
Microsc Res Tech ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38877835

RESUMO

One of the most important areas of nanotechnology is the use of nanoparticles (NPs) for a variety of environmental and biological applications, with silver nanoparticles (Ag-NPs) gaining a lot attention due to their distinct properties. The current study deals with the synthesis of Ag-NPs from Dicliptera bupleuroides Nees leaf extract and to determine their antioxidant, antimicrobial potential and effects on wheat seed germination and growth. UV-Visible spectrum revealed a prominent absorption peak at 442 nm, elucidating the conformation of the Ag-NPs synthesis. Scanning electron microscopy (SEM) showed distinctive triangular, pyramidal, and irregular shape. X-ray diffraction (XRD) demonstrated their crystalline nature, with average crystallite size of the Ag-NPs measured at 20.52 nm. Fourier-transform infrared spectroscopy (FT-IR) further confirmed the presence of functional groups such as Phenols (O-H stretch), transition metal carbonyls N-H, ≡C-H, C ≡ N, C ≡ C, C-Cl, C-Br and O-H bonds on the surface Ag-NPs. The antibacterial activity of the Ag-NPs was most pronounced against Bacillus subtilis, with a zone of inhibition (ZOI) measuring 11 mm ± 0.57 at a concentration of 1000 µg/mL (45% inhibition). Likewise, Ag-NPs exhibited highest antioxidant potential (73.2%) at 100 µg/mL compared with standard (ascorbic acid) which showed (76%) at the same concentration. Furthermore, the effect of D. bupleuroides mediated Ag-NPs on wheat seeds growth and germination was recorded maximum at high concentrations (200-300 ppm). In conclusion, D. bupleuroides mediated Ag-NPs showed safe, cost effective and environmentally friendly synthesis which can be used as an antibacterial and antioxidant agent as well as for enhancing the growth and seed germination of crop seeds globally. RESEARCH HIGHLIGHTS: Nanotechnology is the study of nanoparticles for biological and environmental applications. Ag-NPs among other NPs have received broad attention because of their unique properties. D. bupleuroides Ag-NPs: 45% antibacterial, 73.2% antioxidant, enhance wheat germination. D. bupleuroides-mediated Ag-NPs are both cost-effective and environmentally beneficial.

18.
Microsc Res Tech ; 86(6): 686-693, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36866527

RESUMO

The biogenic synthesis of silver nanoparticles (AgNPs) is an important step in developing eco-friendly and environmentally stable tools for ameliorating crop growth. In the current study, AgNPs were synthesized using Funaria hygrometrica and characterized using ultraviolet (UV) spectroscopy, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD). The UV spectrum showed an absorption peak at 450 nm. SEM revealed an irregular and spherical morphology, FTIR spectroscopy indicated the presence of various functional groups, while XRD displayed peaks at 45.24°, 38.17°, 44.34°, 64.54°, and 57.48° 2θ. The effects of the F. hygrometrica-mediated AgNPs on maize growth and germination were assessed at 0, 100, 300, and 500 ppm. The germination percentage and relative germination rate were increased to 95% ± 1.83% and 100% ± 2.48% at 100 ppm of synthesized AgNPs and then declined at 300 and 500 ppm. The length, fresh weight, and dry matter of the root, shoot, and seedlings were highest at 100 ppm NPs. The plant height, root length, and dry matter stress tolerance indices were also the highest (112.3%, 118.7%, and 138.20% compared with the control) at 100 ppm AgNPs. Moreover, the growth of three maize varieties, that is, NR-429, NR-449, and Borlog, were assessed at 0, 20, 40, and 60 ppm F. hygrometrica-AgNPs. The results indicated the highest root and shoot length at 20 ppm AgNPs. In conclusion, seed priming with AgNPs enhances the growth and germination of maize and can ameliorate crop production globally. RESEARCH HIGHLIGHTS: Funaria hygrometrica Hedw.-mediated AgNPs were synthesized and characterized. Biogenic AgNPs influenced the growth and germination of maize seedlings. All growth parameters were highest at 100 ppm synthesized NPs.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Zea mays , Plântula , Prata/farmacologia , Prata/química , Extratos Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Antibacterianos
19.
PLoS One ; 18(2): e0278568, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36848343

RESUMO

Green biomass is a renewable and biodegradable material that has the potential use to trap urea to develop a high-efficiency urea fertilizer for crops' better performance. Current work examined the morphology, chemical composition, biodegradability, urea release, soil health, and plant growth effects of the SRF films subjected to changes in the thickness of 0.27, 0.54, and 1.03 mm. The morphology was examined by Scanning Electron Microscopy, chemical composition was analyzed by Infrared Spectroscopy, and biodegradability was assessed through evolved CO2 and CH4 quantified through Gas Chromatography. The chloroform fumigation technique was used for microbial growth assessment in the soil. The soil pH and redox potential were also measured using a specific probe. CHNS analyzer was used to calculate the total carbon and total nitrogen of the soil. A plant growth experiment was conducted on the Wheat plant (Triticum sativum). The thinner the films, the more they supported the growth and penetration of the soil's microorganisms mainly the species of fungus possibly due to the presence of lignin in films. The fingerprint regions of the infrared spectrum of SRF films showed all films in soil changed in their chemical composition due to biodegradation but the increase in the thickness possibly provides resistance to the films' losses. The higher thickness of the film delayed the rate and time for biodegradation and the release of methane gas in the soil. The 1.03 mm film (47% in 56 days) and 0.54 mm film (35% in 91 days) showed the slowest biodegradability as compared to the 0.27 mm film with the highest losses (60% in 35 days). The slow urea release is more affected by the increase in thickness. The Korsymer Pappas model with release exponent value of < 0.5 explained the release from the SRF films followed the quasi-fickian diffusion and also reduced the diffusion coefficient for urea. An increase in the pH and decrease in the redox potential of the soil is correlated with higher total organic content and total nitrogen in the soil in response to amending SRF films with variable thickness. Growth of the wheat plant showed the highest average plant length, leaf area index and grain per plant in response to the increase in the film's thickness. This work developed an important knowledge to enhance the efficiency of film encapsulated urea that can better slow the urea release if the thickness is optimized.


Assuntos
Fertilizantes , Filmes Cinematográficos , Biodegradação Ambiental , Biomassa , Ligante de CD40
20.
Heliyon ; 9(5): e15909, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37206037

RESUMO

The present study examined the biological potential and phytochemicals of Sophora mollis, Mucuna pruriens, and Indigofera atropurpurea methanolic leaf extracts. In vitro anti-acetylcholinesterase and anti-lipase assays were performed using different concentrations of plant extracts, and the IC50 values were determined. The cytotoxic potential of the selected plant extracts was assessed against HeLa, PC3, and 3T3 cell lines using an MTT assay. S. mollis leaf extract displayed the highest inhibition percentage (114.60% ± 19.95 at 1000 µg/mL) for the anti-acetylcholinesterase activity with a prominent IC50 value of 75.9 µg/mL. The anti-lipase potential was highest with the M. pruriens leaf extract (355.5 µg/mL IC50), followed by the S. mollis extract (862.7 µg/mL IC50). Among the cell lines tested, the cytotoxic potential of the I. atropurpurea extract (91.1 ppm IC50) against the PC3 cell line was promising. High-performance liquid chromatography revealed gallic acid, chlorogenic acid, caffeic acid, vanillic acid, rutin trihydrate, and quercetin dihydrate in varying concentrations in all plant species. The concentration of chlorogenic acid (69.09 ppm) was highest in M. pruriens, and the caffeic acid concentration (45.20 ppm) was higher in S. mollis. This paper reports the presence of bioactive therapeutic compounds in selected species of the Fabaceae family that could be micro-propagated, isolated, and utilized in pharmaceutical industries.

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