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1.
RSC Adv ; 13(41): 28686-28702, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37790095

RESUMO

C-C coupling reactions represent a fundamental synthetic methodology widely employed in academic and industrial settings. Herein, we present a report on developing and synthesizing a heterogeneous catalyst that is environmentally compatible and has recycling capabilities. Furthermore, the utilization of this catalyst for C-C coupling reactions was explored. A novel amide-based CON was prepared via the reaction of a novel [2,2'-bipyridine]-5,5'-diamine (BDA) and 1,3,5-tris(4-carboxyphenyl) (TCB). TCB was activated with carbonyl diimidazole (CDI) and then reacted with BDA to synthesize favorable CON (i.e., CON-KEY1). Finally, the CON synthesized was reacted with palladium chloride ions, and the palladium-containing organocatalytic complex was decorated with the abbreviated Pd/CON-KEY1. This new heterogeneous complex was fully characterized through the required techniques, including FT-IR, EDX, XRD, TEM, SEM, ICP, TGA-DTA, N2 isotherms, and elemental mapping analysis. Computer simulation results include a multi-sheet 2D framework proposed by CON-KEY1. As a result, palladium ions were found to be arranged between the layers and on the CON surface. This heterogeneous complex functioned as a catalyst precursor in both the Suzuki-Miyaura coupling reaction of aryl boronic acids with aryl halides and the Heck reaction of aryl halides with acrylate derivatives or styrene. The desired coupling products with various functional groups were successfully attained with excellent yields of up to 98%. Simple set-up, improved yields, short reaction times, non-toxic solvents, catalyst durability, and high turnover frequency are among the distinct advantages of this synthetic method. Some other outstanding features of this catalytic system include convenient separation of catalysts and products, high yields, almost complete conversion, high selectivity, and good turnover frequency (TOF). The results show that the highest product efficiency in the reaction was achieved in the shortest possible time using Pd/CON-KEY1. Theoretical studies demonstrated the precedence of the palladium complexation with nitrogen atoms of CON-KEY1 rather than oxygen ones. Natural Bond Orbital (NBO) analysis affirmed that the system with Pd-N bonds (Eg = 0.089 eV) is more reactive with high electron conductivity compared to the Pd-O system (Eg = 0.120 eV).

2.
Nanoscale Adv ; 5(20): 5570-5579, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37822910

RESUMO

Herein, a new catalytic nanocomposite [Co(BDC-NH2)-Pd NPs] composed of a Co(BDC-NH2) MOF has been developed. The catalyst was prepared by modifying the synthesized porous Co(BDC-NH2) MOF with decorated Pd nanoparticles. This nanocatalyst was used as a heterogeneous catalyst in the reductive degradation of organic dyes Rhodamine B and methyl orange with NaBH4. The kinetic and thermodynamic parameters of the reactions were evaluated. The results showed that the low catalyst content could successfully catalyze the dye reduction reaction quickly (1 min). The metal-organic frameworks unique porous morphology of the Co(BDC-NH2) MOF appears to increase dye adsorption and achieve effective dye reduction. Additionally, recyclability studies of the catalyst confirmed that it could be recovered and reused for 10 consecutive reaction cycles with negligible Pd leaching and reduction in catalytic activity.

3.
Chem Biodivers ; 20(11): e202301193, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37869899

RESUMO

A series of [1,3,4] thiadiazolo[3,2-a]pyrimidine-6-carboxylate derivatives 4(a-n) have been designed and synthesized as inhibitors of acetylcholinesterase (AChE). Synthesizing of thiadiazolo[3,2-a] pyrimidines was carried out in a single step, one-pot reaction using aromatic aldehydes, ethyl acetoacetate and different derivatives of 1,3,4-thiadiazoles (with molar ratio of 1 : 2 : 1, respectively) in conjunction with the catalyst, anhydrous iron(III) chloride by a grinding method under solvent-free conditions at room temperature. The in-vitro studies exhibited good potency for inhibiting AChE comparable with donepezil as the reference drug. The best results were obtained by Ethyl 2-(4-nitroophenyl)-7-methyl-5-(pyridin-3-yl)-5H-[1,3,4]thiadiazolo[3,2-a]pyrimidine-6-carboxylate 4n with IC50 value of 0.082±0.001 µM which was comparable with AChE inhibitory effects of donepezil (IC50 =0.079 µM).


Assuntos
Doença de Alzheimer , Inibidores da Colinesterase , Humanos , Inibidores da Colinesterase/farmacologia , Simulação de Acoplamento Molecular , Donepezila , Acetilcolinesterase/metabolismo , Relação Estrutura-Atividade , Teoria da Densidade Funcional , Compostos Férricos , Pirimidinas/farmacologia , Estrutura Molecular
4.
RSC Adv ; 13(35): 24474-24486, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37593669

RESUMO

In this work, a modified electrode named Au/Au NPs-PPy/l-CYs/ZIF-8 was designed and built and simultaneously doped into electropolymerized polypyrrole (PPy) film using cyclic voltammetry (CV). Scanning Electron Microscopy (SEM), Electrochemical Impedance Spectroscopy (EIS), and CV were used to characterize the composite films. The PPy-(ZIF-8) modified Au electrode was used to determine insulin using Square-Wave Voltammetry (SWV). It was found that the prepared zeolitic imidazolate framework-8 had excellent electrocatalytic activity towards insulin oxidation due to its unique properties. The oxidation peak current of insulin hormone increased with its concentration in the range from 1.0 to 60 nM with the linear regression equation: Ipa = 0.3421C (nM) + 3.2762 (γ = 0.998). The measurement limit was estimated to be 1 nM. While the common coexisting substances showed no interference in the response of the modified electrode to insulin, the modified electrode indicated reproducible behavior and a high level of stability during the experiments. The advantages of using these nanocomposites on the surface of modified electrodes include increased stability, good interaction between the analyte and the modified electrode, conductivity, and excellent performance due to the nanometer size of the composites. As a result, it may be particularly suitable for analytical purposes.

5.
RSC Adv ; 13(12): 8114-8129, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36926010

RESUMO

In this study, the synthesis of a novel functionalized metal-organic-framework (MOF) [Cu(BDC-NH2)@Schiff-base-Pd(ii)] catalyst via post-synthetic modification of Cu(BDC-NH2) is reported. The targeted complex was prepared by chemically attaching N,N'-bis(5-formylpyrrol-2-ylmethyl) homopiperazine via a Schiff base reaction followed by complexation with Pd ions. Afterwards, the synthesized solid was applied as a very effective multifunctional catalyst in C-N coupling reactions. The synthesized compounds were identified by suitable techniques including N2 isotherms, EDX spectroscopy, FT-IR spectroscopy, XRD, SEM, ICP-OES and TG-DTA. This nanocatalyst was used in C-N cross-coupling reactions, and it showed its usage in a diverse range of different functional groups with good efficiency. The reasons for introducing this catalyst system are its advantages such as considerably high selectivity, almost complete conversion of products, high yields, and convenient separation of catalysts and products. The results indicate that the highest efficiency of the product in the reaction was obtained in the shortest possible time with the use of [Cu(BDC-NH2)@Schiff-base-Pd(ii)] catalysts. Overall, the high catalytic activity of the [Cu(BDC-NH2)@Schiff-base-Pd(ii)] catalyst may be due to the obtained high surface area and the synergistic features created between Lewis acidic Cu nodes and Pd ions.

6.
Food Chem Toxicol ; 166: 113244, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35728727

RESUMO

Sour cream is a dairy product with good potential to act as a food carrier for probiotic bacteria. The effect of probiotic cultures on the quality of sour cream from dry dairy ingredients was assessed during 5 weeks of storage. The treatments design was as follows: Bifidobacterium, Bifidobacterium + Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus acidophilus + Lactobacillus casei and Lactobacillus casei. Fatty acids profile, texture, microbial load and sensory characteristics were analyzed. Comparison of fatty acids of different creams produced showed that there is a significant difference between the produced creams. There are a wide range of fatty acids in the structure of sour cream fat. Also, with the addition of these bacteria, the texture of the samples became firmer during storage. The sensory analyses showed that the addition of all three bacteria increased the overall acceptance of this product by the panelists. It is suggested that sour cream fortified with probiotics well orientated functional food had accepted composition and sensory properties.


Assuntos
Lacticaseibacillus casei , Probióticos , Bifidobacterium , Ácidos Graxos , Lactobacillus acidophilus
7.
BMC Complement Altern Med ; 18(1): 206, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29973195

RESUMO

BACKGROUND: We aimed to evaluate the effects of a hydroalcoholic extract of Juglans regia L. leaves on blood glucose level and cardiovascular risk factors in type 2 diabetic patients. METHODS: In this randomized, double-blind, placebo-controlled, parallel-group (2 arms) clinical trial, 50 diabetic patients were divided into two groups: treatment group (receive the capsules containing 100 mg J. regia leaf extract) and control group (receive the capsules containing placebo, microcrystallin cellulose). Baseline participant data were matched between the two arms of the study. We administered the prepared capsules to the patients twice daily for 8 weeks. Blood glucose level, glycosylated hemoglobin (HbA1c) level, body weight, body mass index, blood pressure, lipid profile, serum insulin, and insulin resistance were compared between the two groups before and after the intervention. P < 0.05 was considered significant. RESULTS: After excluding eleven patients, 20 received J. regia leaf extract and 20 patients received placebo. The J. regia leaf extract did not significantly change the blood glucose and insulin resistance condition. However, in this group, body weight, body mass index, and systolic blood pressure significantly decreased compared with the baseline measurements (P = 0.028, P = 0.030, and P = 0.005, respectively). The lipid profile did not change significantly compared with the baseline measurements. In the control group, postprandial glucose and HbA1c levels significantly decreased after the intervention (P = 0.030 and P = 0.028, respectively). The other variables were not significantly different in this group. At the end of the study, the variables were not significantly different between the two groups. CONCLUSION: In this double-blind study, 200 mg/d of J. regia leaf extract had no significant effect on blood glucose level and HOMA-IR score in patients with type 2 diabetes. However, the J. regia leaf extract was effective in reducing body weight and blood pressure. An accidental finding of our study was that microcrystalline cellulose, a widely used placebo in clinical trials, led to a reduction in blood glucose level. TRIAL REGISTRATION: Iranian Registry of Clinical Trials (IRCT: 138901203180 N2 , 2010/6/6); retrospectively registered.


Assuntos
Glicemia/efeitos dos fármacos , Doenças Cardiovasculares/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Juglans/química , Extratos Vegetais/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/efeitos dos fármacos , Colesterol/sangue , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Folhas de Planta/química , Fatores de Risco
8.
Ultrason Sonochem ; 24: 150-4, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25583096

RESUMO

A novel and convenient method for synthesis of gem-dichloroaziridine derivatives was reported in that was utilized Mg powder with CCl4 for dichlorocarbene generation under ultrasonic irradiation. In this clean and efficient reaction procedure, the desired products were purely obtained in excellent yields. The other advantages of this method are availability of reagents, very short reaction times, simplicity of the method, easily work up, neutral reaction medium and high purity of products.

9.
Caspian J Intern Med ; 5(1): 26-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24490010

RESUMO

BACKGROUND: Hirsutism is a common symptom presenting to primary care endocrinologists, gynecologists, and dermatologists. Management is usually a long and troublesome process. This study was designed to evaluate the effect of fennel topical gel on mild to moderate idiopathic hirsutism. METHODS: The randomized, double-blind, placebo-controlled clinical trial was carried out from 2009 to 2011, in Sari, Iran. Forty four women with mild to moderate idiopathic hirsutism were randomly divided to case and control groups, each group included 22 cases. The case group received fennel gel 3% and the control group received placebo. The effect of fennel gel 3% was defined as reduction of thickness of facial hair in micrometer by microscope in comparison with placebo. Measurements were performed at zero time and 24 weeks after treatment. This study was registered in the Iranian Registry of Clinical Trial (www.irct.ir) with registration number 138901213672N1. RESULTS: The mean age of patients was 26.9±6.7 and 25.6±4.3 years in case and control groups, respectively. Hair thickness was similar between the two groups before intervention. The hair thickness reduced from 97.9±31.5 to 75.6±26.7 micron in patients receiving fennel gel after 24 weeks (P<0.001). Four patients complained of itching (3 in case group) and 4 patients complained of irritation and itching (3 in case group). However, this difference was not statistically significant. CONCLUSION: The study indicated that fennel gel 3% is effective in decreasing hair thickness in women with idiopathic mild to moderate hirsutism.

10.
Iran J Psychiatry Behav Sci ; 7(2): 77-82, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24644513

RESUMO

OBJECTIVE: This study has been done in order to evaluate the papers published in the "Iranian Journal of Psychiatry and Behavioral Sciences" from 2007 to 2010. METHODS: A questionnaire was developed according to the design, evidence level, and recommendations to write scientific papers. Validity was achieved by consulting experts. Reliability was tested by re-evaluation of 7 randomly selected papers, one month after the first evaluation by Pearson correlation coefficient (r = 0.8). Different parts of the paper, including title, abstract, introduction, materials and methods, results, discussion, and references, were evaluated by a total of 47 questions. Each required item was judged as: appropriate, partially appropriate, not appropriate, and not applicable. SPSS software was used for descriptive analysis. RESULTS: From spring 2007 to summer 2010, 7 issues with 72 papers were published. The most frequent problem in the title was that one could not understand the design of the research by reading it. In the abstract part, in 90% of papers, time and setting of research were not mentioned. Statistical test was not mentioned in 70%, and reliability of the questionnaires was not mentioned in 70% of papers. The discussion part was the hardest part to judge and had few inappropriate issues, such as unnecessary repetition of introduction and/or results; in 20% of papers the conclusion was not appropriate based on the research design. CONCLUSIONS: The evaluated papers had strong points, yet more effort is needed for them to approach excellence. DECLARATION OF INTEREST: None.

11.
Ultrason Sonochem ; 19(1): 130-5, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21775185

RESUMO

In this research, rapid and efficient preparation of 2,2-dichloro-1,3-diarylaziridines through the reaction of Schiff base compounds with dichlorocarbene yielded in situ from chloroform and sodium hydroxide without any phase transfer catalyst under ultrasonic irradiation is described. The advantages of this reaction are very short reaction times, excellent product yields, simplicity of the method and high purity of products.


Assuntos
Álcalis/química , Aziridinas/síntese química , Ultrassom , Aziridinas/química , Catálise , Hidrocarbonetos Clorados/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Bases de Schiff/química , Estereoisomerismo
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