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1.
Org Biomol Chem ; 22(17): 3425-3438, 2024 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-38590227

RESUMEN

We have applied the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction to prepare a library of ten coumarin-azasugar-benzyl conjugates and two phthalimide-azasugar-benzyl conjugates with potential anti-Alzheimer and anti-cancer properties. The compounds were evaluated as cholinesterase inhibitors, demonstrating a general preference, of up to 676-fold, for the inhibition of butyrylcholinesterase (BuChE) over acetylcholinesterase (AChE). Nine of the compounds behaved as stronger BuChE inhibitors than galantamine, one of the few drugs in clinical use against Alzheimer's disease. The most potent BuChE inhibitor (IC50 = 74 nM) was found to exhibit dual activities, as it also showed high activity (GI50 = 5.6 ± 1.1 µM) for inhibiting the growth of WiDr (colon cancer cells). In vitro studies on this dual-activity compound on Cerebellar Granule Neurons (CGNs) demonstrated that it displays no neurotoxicity.


Asunto(s)
Antineoplásicos , Butirilcolinesterasa , Proliferación Celular , Inhibidores de la Colinesterasa , Cumarinas , Cumarinas/química , Cumarinas/farmacología , Cumarinas/síntesis química , Butirilcolinesterasa/metabolismo , Humanos , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/síntesis química , Proliferación Celular/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Animales , Línea Celular Tumoral , Relación Estructura-Actividad , Estructura Molecular , Ensayos de Selección de Medicamentos Antitumorales , Compuestos Aza/química , Compuestos Aza/farmacología , Compuestos Aza/síntesis química , Relación Dosis-Respuesta a Droga , Neuronas/efectos de los fármacos
2.
Environ Sci Pollut Res Int ; 31(17): 24852-24867, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38460034

RESUMEN

Two applications of spirotetramat were done to study the dissipation and persistence of spirotetramat and its four different metabolites in chilli and soil at 10 days interval. Total spirotetramat residues were estimated by LC-MS/MS instrument. The mean initial deposits of total spirotetramat after application of spirotetramat 15.31 OD @ 60 (X dose), 75 (1.25 × dose) and 120 (2 × dose) g a.i. ha-1 on green chilli were found to vary from 0.38 to 0.83 mg kg-1 during the initial year. Spirotetramat and its metabolite residues in green chilli were found to be below limit of quantification (0.01 mg kg-1) after 15 days of application. The spirotetramat cis enol (the major metabolite) was formed in both the soil and the plant. The residues of spirotetramat-monohydroxy were below LOQ irrespective of any substrate during the estimation. In soil, the total initial spirotetramat deposits for the 1st year were found 0.09 for X dose, 0.12 for 1.25 × dose and 0.20 mg kg-1 for 2 × dose. After 3 days for both X and 1.25 × doses and 5 days for 2 × dose, the total spirotetramat residues were below LOQ. The spirotetramat's half-life values have been determined to be between 3.19 and 3.93 days and 1.00 and 1.59 days, respectively, in soil and green chilli fruits. One day waiting period is proposed for the safe consumption of green chilli when the spirotetramat was applied irrespective of the dose.


Asunto(s)
Compuestos Aza , Insecticidas , Residuos de Plaguicidas , Contaminantes del Suelo , Compuestos de Espiro , Insecticidas/análisis , Cromatografía Liquida , Cromatografía Líquida con Espectrometría de Masas , Suelo/química , Espectrometría de Masas en Tándem , Contaminantes del Suelo/análisis , Residuos de Plaguicidas/análisis , Semivida
3.
Environ Sci Pollut Res Int ; 31(17): 25736-25750, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38488914

RESUMEN

A field experiment following good agricultural practices was laid out to study the dissipation of spirotetramat (90 g a.i. ha-1 and 180 g a.i. ha-1) and chlorpyrifos (400 g a.i. ha-1 and 800 g a.i. ha-1) on cabbage heads and soil. Samples were processed using quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for residue estimation of spirotetramat and chlorpyrifos, which were further detected using HPLC-PDA and GC-FPD respectively. The residues of spirotetramat on cabbage heads reached below detection limit (BDL) (< 0.05 mg kg-1) on 7th and 10th day and for chlorpyrifos, BDL (< 0.01 mg kg-1) was achieved on 10th and 15th day for X and 2X dose, respectively. On 20th day after second spray, residues in soil were found to be BDL for both the pesticides. Half-life of spirotetramat and chlorpyrifos was found to be 3 and 2 days, respectively while a safe pre-harvest interval (PHI) of 9 days for spirotetramat and 10 days for chlorpyrifos is suggested on cabbage. The dietary risk assessment studies for various age groups of Indian population, ascertained safety of treated cabbage heads for consumption, as current study revealed that hazard quotient (HQ) < 1 and theoretical maximum dietary intake (TMDI) < maximum permissible intake (MPI) for both the pesticides at respective PHI.


Asunto(s)
Compuestos Aza , Brassica , Cloropirifos , Residuos de Plaguicidas , Plaguicidas , Contaminantes del Suelo , Compuestos de Espiro , Suelo/química , Brassica/química , Residuos de Plaguicidas/análisis , Contaminantes del Suelo/análisis , Plaguicidas/análisis , Medición de Riesgo , Semivida
4.
J Biomol Struct Dyn ; 42(7): 3507-3519, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37855303

RESUMEN

Lung Cancer is the one that causes more fatalities in the world compared to other cancers, and its uniqueness is that it can be found in both males and females. However, recent data has shown that males are more affected due to lifestyle habits like smoking, tobacco consumption and inhaling polluted air. The World Health Organization has kept lung cancer on its priority list as it causes 1.8 million deaths worldwide each year, and the predictions show that the cases are going to increase year by year, and by 2050, there can be 3.8 million new cases and 3.2 million deaths, and the global health system is not prepared for it. Also, finding drug candidates that can help shrink cancerous cells and lead to their death is essential to reduce global mortality. The system needs drug compounds that can inhibit multiple paths together not to enter drug resistance quickly and to reduce costs. Our study identified a compound named Variolin B (DB08694) that belongs to the organic compounds class of pyrrolopyridines. The identified compound can inhibit multiple proteins, drastically reducing the global burden. Variolin B was identified as a potential candidate against lung cancer using the multisampling algorithm such as HTVS, SP, and XP, followed by MM\GBSA calculations showing the docking score of -9.245 Kcal/mol to -5.92 Kcal/mol. Also, we have validated it with ADMET predictions and molecular fingerprinting to analyse the interaction patterns. Further, the study was extended to molecular dynamics simulations for 100 ns to understand the complex stability and simulative interactions. The complex's overall molecular dynamics simulation helped us understand that the identified candidate is stable with the lowest deviation and fluctuations.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Compuestos Aza , Neoplasias Pulmonares , Pirimidinas , Femenino , Masculino , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Neoplasias Pulmonares/tratamiento farmacológico
5.
Environ Sci Pollut Res Int ; 31(4): 6277-6287, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38147257

RESUMEN

Spirotetramat is widely used around the world to control sucking pests and may form in agricultural products. In the current study, the dissipation, residues, and evaluation of processing factor (PF) for spirotetramat and its formed metabolites were investigated during kiwifruit growing, storing, and processing. The residue analysis method was established based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) combined with a QuEChERS method to detect the residues of spirotetramat and its metabolites in kiwifruit and its processed products. The method provided recoveries of 74.7-108.7%, and the relative standard deviations (RSDs) were 0.6-13.1%. The LOQs of spirotetramat and its four metabolites were 1 µg kg-1. The degradation of spirotetramat was best fitted for the first-order kinetics model with a half-life of 9.90-10.34 days in the field and 24.75-30.13 days during storage. Residues of spirotetramat and its formed metabolites in kiwifruit would not pose dietary risk to consumers. Moreover, the peeling and fermentation were the highest removal efficiency for the spirotetramat and its formed metabolite residues during processing. The PF values calculated after each individual process were < 1, indicating a significant reduction of residues in different processing processes of kiwifruit. The spirotetramat was degraded during kiwifruit wine-making process with half-lives of 3.36-4.91 days. B-enol and B-keto were the main metabolites detected in kiwifruit and its processed products. This study revealed the residues of spirotetramat and its formed metabolites in kiwifruit growing, storing, and processing, which helps provide reasonable data for studying the dietary risk factors of kiwifruits and products.


Asunto(s)
Compuestos Aza , Residuos de Plaguicidas , Compuestos de Espiro , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión , Compuestos Aza/química , Compuestos de Espiro/química , Residuos de Plaguicidas/análisis
6.
Environ Pollut ; 343: 123242, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38154778

RESUMEN

Spirotetramat (SPT), a tetronic acid-derived insecticide, is implicated in reproductive and lipid metabolism disorders, as well as developmental toxicity in fish. While these effects are documented, the precise mechanisms underlying its developmental toxicity are not fully elucidated. In this study, zebrafish embryos (2 h post-fertilization, hpf) were exposed to four concentrations of SPT (0, 60, 120, and 240 µg/L) until 21 dpf (days post-fertilization). We delved into the mechanisms by examining its potential disruption of the thyroid endocrine system, employing in vivo, in vitro, and in silico assays. The findings showed notable developmental disturbances, including reduced hatching rates, shortened body lengths, and decelerated heart rates. Additionally, there was an increase in malformations and a decline in locomotor activity. Detailed analyses revealed that SPT exposure led to elevated thyroid hormone levels, perturbed the hypothalamic-pituitary-thyroid (HPT) axis transcript levels, amplified deiodinase type I (Dio1) and deiodinase type II (Dio2) activities, and both transcriptionally and proteomically upregulated thyroid receptor beta (TRß) in larvae. Techniques like molecular docking and surface plasmon resonance (SPR) confirmed SPT's affinity for TRß, consistent with in vitro findings suggesting its antagonistic effect on the T3-TR complex. These insights emphasize the need for caution in using tetronic acid-derived insecticides.


Asunto(s)
Compuestos Aza , Compuestos de Espiro , Glándula Tiroides , Contaminantes Químicos del Agua , Animales , Pez Cebra/metabolismo , Larva , Simulación del Acoplamiento Molecular , Yoduro Peroxidasa/metabolismo , Contaminantes Químicos del Agua/metabolismo
7.
Eur J Med Chem ; 261: 115804, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37729693

RESUMEN

A number of new disubstituted 6-azaindoles have been designed and synthesized bearing a crucial structural modification in respect to an analogous antiproliferative hit compound. The synthesis was performed using 2-amino-3-nitro-4-picoline, that was suitably modified and converted to 7-chloro-3-iodo-6-azaindole and this central scaffold was used for successive Suzuki-type couplings, to result in the target compounds. The evaluation of the cytotoxic activity was performed against four human cancer cell lines, as well as a normal human fibroblast strain. Certain compounds possessed strong anticancer activity without affecting normal cells. At subcytotoxic concentrations for cancer cells, these compounds displayed an anti-proliferative effect by arresting the cells at the G2/M phase of the cell cycle, which could be associated with the observed decrease in the phosphorylation levels of the MEK1- ERK1/2 pathway and/or the activation of the p53-p21WAF1 axis.


Asunto(s)
Antineoplásicos , Compuestos Aza , Humanos , Antineoplásicos/química , Compuestos Aza/farmacología , Ciclo Celular , División Celular , Proliferación Celular , Línea Celular Tumoral , Apoptosis
8.
PeerJ ; 11: e15745, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37601256

RESUMEN

The leaf worm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) is a notorious insect pest of many economically important cultivated crops like cotton, maize, tobocco and vegetables causing severe economic losses from 50-100%. In most crops, damage arises due to voracious feeding by the larvae and leads to the skeletonizing of leaves. Toxicological studies were performed to estimate lethal and sublethal levels of flubendiamide and spirotetramat against S. litura. Effects of these estimated values were assessed on different biological traits of S. litura including life duration, survival and next generation potential. Both flubendiamide and spirotetramat showed toxic responses against second instar larvae of S. litura under laboratory conditions. Larval duration and survival rate of S. litura to were significantly different. Exposure to test insecticides resulted in negative effect on the demography of S. litura as longer life cycle and decreased fecundity. Changes in net reproductive rate and intrinsic rate of increase also helped to decide the fate of these insecticides. Low reproductive potential and low hatching percentage due to exposure to test insecticides can help to manage next generation of target pest. These two new chemistry insecticides can be recommended for their effective and long-term utilization against this important leaf feeder which may help its management and decrease economic losses faced by the growers. Their impact on larval duration and low survival rate at lethal levels guides about their potential in pest control.


Asunto(s)
Compuestos Aza , Insecticidas , Animales , Spodoptera , Insecticidas/toxicidad , Benzamidas/farmacología , Productos Agrícolas , Larva
9.
J Econ Entomol ; 116(5): 1737-1749, 2023 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-37598313

RESUMEN

The gall wasp, Hemadas nubilipennis Ashmead, is a pest of highbush and lowbush blueberry and can pose a challenge to control with foliar sprays due to adult activity being during bloom and because larval development is within plant tissues. We hypothesized that systemic insecticides that move within the blueberry vascular system would reach areas where H. nubilipennis eggs are laid, causing larval mortality. Three application methods, crown injection, soil drench, and foliar spray were applied to potted 'Jersey' blueberry bushes at 50% and 100% rates to quantify systemic residue concentrations in shoots and leaves. Additionally, systemic insecticides were evaluated for control of gall wasps using single-shoot bioassays and measuring larval mortality at 0.01%, 0.1%, 1%, and 10% of field rate provided within a floral pick. Systemic insecticides tested in both studies included imidacloprid, flupyradifurone, and spirotetramat. The potted bush residue study determined that insecticides moved from three tested sites of entry: the roots, crown cavity, and foliage. Results from the shoot bioassays found that the mean percent larval survival of H. nubilipennis was negatively correlated with the concentration of AI detected in galls. Imidacloprid and spirotetramat were found to have the greatest potential for control of H. nubilipennis due to mortality in the shoot bioassays and similar residue concentrations in the potted bush studies to shoot bioassays. Future research should evaluate systemic insecticides applied in highbush blueberry plantings for control of H. nubilipennis using the bioassay mortality assessment method developed in this study.


Asunto(s)
Compuestos Aza , Arándanos Azules (Planta) , Insecticidas , Neonicotinoides , Nitrocompuestos , Compuestos de Espiro , Avispas , Animales , Insecticidas/farmacología , Larva
10.
Inorg Chem ; 62(50): 20677-20687, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-37487036

RESUMEN

Herein, we present the synthesis and coordination chemistry of copper(II) and zinc(II) complexes of two novel heterocyclic triazacyclononane (tacn)-based chelators (HNODThia and NODThia-AcNHEt). The chelator HNODThia was further derivatized to obtain a novel PSMA-based bioconjugate (NODThia-PSMA) and a bifunctional photoactivatable azamacrocyclic analogue, NODThia-PEG3-ArN3, for the development of copper-64 radiopharmaceuticals. 64Cu radiolabeling experiments were performed on the different metal-binding chelates, whereby quantitative radiochemical conversion (RCC) was obtained in less than 10 min at room temperature. The in vitro stability of NODThia-PSMA in human plasma was assessed by ligand-challenge and copper-exchange experiments. Next, we investigated the viability of the photoactivatable analog (NODThia-PEG3-ArN3) for the light-induced photoradiosynthesis of radiolabeled proteins. One-pot photoconjugation reactions to human serum albumin (HSA) as a model protein and the clinically relevant monoclonal antibody formulation MetMAb were performed. [64Cu]Cu-7-azepin-HSA and [64Cu]Cu-7-azepin-onartuzumab were prepared in less than 15 min by irradiation at 395 nm, with radiochemical purities (RCP) of >95% and radiochemical yields (RCYs) of 42.7 ± 5.3 and 49.6%, respectively. Together, the results obtained here open the way for the development of highly stable 64Cu-radiopharmaceuticals by using aza-heterocyclic tacn-based chelators, and the method can easily be extended to the development of 67Cu radiopharmaceuticals for future applications in molecularly targeted radio(immuno)therapy.


Asunto(s)
Compuestos Aza , Quelantes , Humanos , Quelantes/química , Radiofármacos/química , Cobre , Radioisótopos de Cobre/química , Tomografía de Emisión de Positrones/métodos
11.
Chem Biodivers ; 20(7): e202300158, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37272557

RESUMEN

Herein, we report synthesis, characterization, antimicrobial and antimalarial activities of azines Schiff base ligands (L1 -L4 ) and their palladium (II) complexes (C1 -C4 ) of [Pd(L)(OAc)2 ] type. The azine ligands (L1 -L4 ) were prepared by condensation of carbonyl compounds with hydrazine hydrate and their complexes by the reaction of palladium acetate with L1 -L4 ligands in 1 : 1 molar ratio. The prepared ligands and their complexes were characterized by spectral characterization using 1 H &13 C-NMR, FT-IR and mass spectral studies, which revealed that the ligands coordinates via azomethine nitrogen and heteroatom or aryl carbon with palladium. Moreover, Schiff bases and their palladium (II) complexes have been screened for their antibacterial (S. aureus, B. subtillis, and S. typhi, P. aeruginosa), antifungal (C. albicans, A. niger, and A. clavatus) and antimalarial (P. falciparum) activities. The Schiff base L4 showed good results for antibacterial against S. aureus (MIC, 50 µg/mL) and antimalarial against P. falciparum (IC50 , 0.83 µg/mL). The complex C1 showed best antibacterial activity (MIC, 62.5 µg/mL) against S. typhi and the complex C4 exhibited remarkable antimalarial activity (IC50 , 0.42 µg/mL) among the tested compounds. Thus, azines based ligands and their Pd complexes can be good antimicrobial and antimalarial agents if explored further.


Asunto(s)
Antiinfecciosos , Antimaláricos , Complejos de Coordinación , Antibacterianos/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Antimaláricos/farmacología , Candida albicans , Complejos de Coordinación/química , Ligandos , Pruebas de Sensibilidad Microbiana , Paladio/química , Bases de Schiff/química , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus , Compuestos Aza/química
12.
Antimicrob Agents Chemother ; 67(6): e0037423, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37154772

RESUMEN

Results from this large, multicenter study suggest that patients with a confirmed ciprofloxacin, moxifloxacin, or levofloxacin hypersensitivity reaction are likely to tolerate other fluoroquinolones. Avoiding different fluoroquinolones in patients labeled with a ciprofloxacin, moxifloxacin, or levofloxacin allergy may not always be mandatory. This was a study of patients with a ciprofloxacin, moxifloxacin, or levofloxacin hypersensitivity reaction and a documented electronic medical record administration of a different fluoroquinolone. Numerically, the most common reaction risk occurred with a challenge to moxifloxacin (2/19; 9.5%), followed by ciprofloxacin (6/89; 6.3%), and levofloxacin (1/44; 2.2%).


Asunto(s)
Compuestos Aza , Hipersensibilidad , Quinolinas , Humanos , Fluoroquinolonas/efectos adversos , Moxifloxacino/efectos adversos , Levofloxacino/efectos adversos , Antibacterianos/efectos adversos , Ciprofloxacina , Hipersensibilidad/tratamiento farmacológico , Quinolinas/efectos adversos , Ofloxacino
13.
Environ Sci Pollut Res Int ; 30(5): 12618-12627, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36114962

RESUMEN

As an ideal nanocarrier, mesoporous silica nanoparticles (MSNs) have the characteristics of high specific surface area, adjustable pore size, and good biocompatibility, which are excellent carriers for improving the stability and sustained-release performance of pesticides and improving the utilization rate of pesticides In this study, three kinds of particle size MSNs (100 nm, 200 nm, and 400 nm) were prepared by hydrothermal synthesis method, and then, the spirotetramat (Stm) was loaded into MSNs with different particle sizes by solvent volatilization method to prepare Stm nanoparticles with different particle sizes (Stm@MSNs). The results of Stm@MSNs characterization showed that the three particle sizes of MSNs were 112.5, 200.1, and 439.4 nm, respectively. Besides, the pore sizes of the three MSNs were all in the range of 2~50 nm. And the FTIR spectra showed that the Stm was successfully loaded into the channel of MSNs. TGA analysis showed that Stm@MSNs-100, Stm@MSNs-200, and Stm@MSNs-400 had good thermal stability in the range of 200°C. The drug loads of Stm@MSNs-100, Stm@MSNs-200, and Stm@MSNs-400 to Stm were 38%, 21%, and 53%. The release test showed that all of them showed the characteristics of slow release. After 3 days of application on cucumber plants, Stm was detected in both upper and lower leaves of cucumber. Compared with MSNs-200 and MSNs-400, the nanocarrier MSNs-100 were more easily absorbed by cucumber plants and could carry more Stm into cucumber plants. This study provided a theoretical basis for the development and application of nanocarriers and the improvement of pesticide utilization rate by discussing the effects of different particle size MSNs on the slow release and systemicity of pesticides.


Asunto(s)
Compuestos Aza , Cucumis sativus , Nanopartículas , Plaguicidas , Dióxido de Silicio , Porosidad , Portadores de Fármacos
14.
Pestic Biochem Physiol ; 188: 105282, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36464337

RESUMEN

Spirotetramat is a novel insecticide and acaricide that can effectively control many species of piercing-sucking pests by inhibiting lipid synthesis. The silkworm is an economically important insect and a model organism for genetics and biochemical research. However, the toxic effect on their development and reproduction remain unclear. In this study, we demonstrated the negative effects of spirotetramat on the development, vitality, silk protein synthesis, and fecundity of silkworm. We also compared expression changes of silkworm genes using digital gene expression (DGE). A total of 1567 differentially expressed genes (DEGs) were detected, of which 874 genes were downregulated and 693 genes were upregulated. Gene Ontology (GO) enrichment analysis showed that the DEGs were enriched in the oxidation-reduction process, oxidoreductase activity, and fatty-acyl-CoA reductase activity. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the DEGs were mainly enriched in fatty acid metabolism and lysosome pathways. We detected the relative expression of silkworm genes related to fatty acid synthesis and decomposition pathways and the degradation pathway of juvenile hormone by quantitative real-time PCR. The expression levels of Acetyl CoA carboxylase (ACC), fatty acyl-CoA reductase (FACR), Enoyl-CoA hydratase (ECH), very-long-chain (3R)-3-hydroxyacyl-CoA dehydratase (LCHAD), juvenile hormone epoxide hydrolase (JHEH), and phytanoyl-CoA dioxygenase (PCD) genes were downregulated. These data demonstrate the effects of spirotetramat on silkworm and its effects on genes involved in fatty acid metabolism.


Asunto(s)
Compuestos Aza , Bombyx , Animales , Bombyx/genética , Compuestos Aza/toxicidad , Reproducción , Ácidos Grasos
15.
Angew Chem Int Ed Engl ; 61(50): e202214090, 2022 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-36253886

RESUMEN

The sulfur fluoride exchange (SuFEx) reaction is significant in drug discovery, materials science, and chemical biology. Conventionally, it involves installation of SO2 F followed by fluoride exchange by a catalyst. We report catalyst-free Aza-Michael addition to install SO2 F and then SuFEx reaction with amines, both occurring in concert, in microdroplets under ambient conditions. The microdroplet reaction is accelerated by a factor of ∼104 relative to the corresponding bulk reaction. We suggest that the superacidic microdroplet surface assists SuFEx reaction by protonating fluorine to create a good leaving group. The reaction scope was established by performing individual reactions in microdroplets of 18 amines in four solvents and confirmed using high-throughput desorption electrospray ionization experiments. The study demonstrates the value of microdroplet-assisted accelerated reactions in combination with high-throughput experimentation for characterization of reaction scope.


Asunto(s)
Química Clic , Fluoruros , Aminas , Fluoruros/química , Compuestos de Azufre , Compuestos Aza
16.
Phys Chem Chem Phys ; 24(41): 25495-25505, 2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36254626

RESUMEN

Aza-BODIPY compounds with methoxy groups at -3 and -5 and triphenylamine moieties at -1 and -7 positions with and without heavy bromine atoms at -2 and -6 positions have been designed and synthesized. The chemical structures of the novel compounds were fully characterized using 1H NMR, 13C NMR, FTIR, and HRMS-TOF-ESI techniques. Steady-state absorption and emission features were investigated to analyze ground-state interactions. The effects of triphenylamine moieties and bromine atoms on charge transfer dynamics and two-photon absorption (TPA) properties were investigated using femtosecond transient absorption spectroscopy measurements and open-aperture (OA) Z-scan experiments, respectively. Contrary to popular belief, the compound containing heavy bromine atoms and triphenylamine moieties did not demonstrate any triplet transition. Since the triphenylamine moiety has high electron-donating properties and a long conjugation length, it exhibited intramolecular charge transfer (ICT) features from electron-donating moieties to the aza-BODIPY core. Additionally, it is concluded that the excited-state lifetime is shortened in the presence of a bromine atom with triphenylamine moieties. This result is rather interesting since the triplet excited state is quenched by the triphenylamine moiety despite the presence of a heavy bromine atom. The performed OA Z-scan experiments revealed that the aza-BODIPY compound containing bromine atoms has a higher TPA cross-section value (116 GM) due to efficient intramolecular charge transfer compared to that without bromine atoms (89 GM). Additionally, in the theoretical calculations, it was found that the charge transfer percentage (CT%) was the strongest in compounds containing bromine atoms.


Asunto(s)
Compuestos Aza , Fármacos Fotosensibilizantes , Fármacos Fotosensibilizantes/química , Bromo , Teoría Cuántica , Compuestos de Boro/química , Compuestos Aza/química
17.
Org Biomol Chem ; 20(44): 8657-8661, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36281731

RESUMEN

A palladium-catalyzed bay-region annulative π-extension reaction of o-halobiphenyls with o-chloropyridinecarboxylic acids was developed. The reaction was carried out with a 1 : 1 ratio of substrates. A variety of azatriphenylene derivatives could be synthesized by this approach. This transformation could be applied to the synthesis of ionic liquid-crystalline molecules.


Asunto(s)
Compuestos Aza , Paladio , Paladio/química , Catálisis , Crisenos
18.
Bioorg Chem ; 128: 106095, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36049321

RESUMEN

Ribosome assisted protein synthesis in all prokaryotes begins with a formylated methionine. Deformylation and demethionylation of these newly synthesized proteins are critical co-translational events carried out by peptide deformylase (PDF) and methionine aminopeptidase (MetAP) in all living cells. Since the mechanism of N-terminal modification is common between the infectious microbes and the host human cells, it is a challenge to identify selective inhibitors. Given that both MetAP and PDF are metalloenzymes, and have strong affinity for hydroxamic acids, we reasoned that the azaindole-based hydroxamic acids could inhibit the PDF enzymes. In the present study we describe the screening of a 17-compound library with 4- and 5- substituted azaindole hydroxamic acid derivatives against PDF enzyme from H. influenzae (HiPDF), M. tuberculosis (MtPDF) and human PDF (HsPDF). Several of these molecules showed nanomolar inhibition against HiPDF enzyme, best at 21 nM (15). On the other hand, none of these compounds inhibited the human enzyme while only two molecules showed moderate inhibition against Mtb enzyme. Surprisingly only 5-substituted azaindole derivatives inhibited the PDF enzymes. Some of the 5-substituted azaindole compounds inhibited the growth of different microbes indicating their potential application in antimicrobial therapy. Crystallographic and modeling studies provided the mechanistic view of regioselective inhibition.


Asunto(s)
Haemophilus influenzae , Ácidos Hidroxámicos , Amidohidrolasas , Antibacterianos/farmacología , Compuestos Aza , Inhibidores Enzimáticos/química , Escherichia coli , Haemophilus influenzae/metabolismo , Humanos , Ácidos Hidroxámicos/química , Indoles , Metionina/metabolismo
19.
J Environ Sci Health B ; 57(9): 765-773, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36093783

RESUMEN

Research work featured in this article describes the impurity profile of spirotetramat, a widely used broad-spectrum pesticide targeting acetyl-CoA carboxylase. Technical grade spirotetramat from four different sources were analyzed and compared with commercial Movento using UPLC-MS. Seven potential impurities were detected and six of them except for the trans-isomer of spirotetramat were subsequently isolated using preparative HPLC. All impurities were characterized mainly by MS and NMR spectroscopy and their structures were further confirmed by chemical synthesis. The formation of the impurities was described in this report as well.


Asunto(s)
Plaguicidas , Espectrometría de Masas en Tándem , Acetil-CoA Carboxilasa , Compuestos Aza , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida/métodos , Contaminación de Medicamentos , Compuestos de Espiro , Espectrometría de Masas en Tándem/métodos
20.
Bioorg Med Chem Lett ; 74: 128925, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35944852

RESUMEN

A series of 1-oxa-4-azaspiro[4,5]deca-6,9-diene-3,8-dione derivatives containing structural fragments of conjugated dienone have been synthesized previously by our group, however the Michael addition reaction between conjugated dienone and nucleophilic groups in the body may generate harmful and adverse effects. To reduce harmful side effects, the authors started with p-aminophenol to make 1-oxo-4- azaspirodecanedione derivatives, then utilized the Michael addition and cyclopropanation to eliminate α, ß unsaturated olefinic bond and lower the Michael reactivity of the compounds in vivo for optimization. At the same time, heteroatoms are put into the molecules in order to improve the hydrophilicity of the molecules and the binding sites of the molecules and the target molecules, establishing the groundwork for improved antitumor activity. The majority of the compounds had moderate to potent activity against A549 human lung cancer cells, MDA-MB-231 breast cancer cells, and Hela human cervical cancer cells. Among them, the compound 6d showed the strongest effect on A549 cell line with IC50 of 0.26 µM; the compound 8d showed the strongest cytotoxicity on MDA-MB-231 cell line with IC50 of 0.10 µM; and the compound 6b showed the strongest activity on Hela cell line with IC50 of 0.18 µM.


Asunto(s)
Antineoplásicos , Compuestos Aza/farmacología , Compuestos de Espiro/farmacología , Antineoplásicos/química , Compuestos Aza/química , Línea Celular Tumoral , Proliferación Celular , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Células HeLa , Humanos , Estructura Molecular , Compuestos de Espiro/síntesis química , Relación Estructura-Actividad
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