Journal of the Brazilian Chemical Society最新文献_第6页

Magnetic Nanoparticles Based on DABCO as Catalysts in the Knoevenagel Reaction and Synthesis of Isatin-β-thiosemicarbazones 基于DABCO的磁性纳米颗粒在Knoevenagel反应及Isatin-β-硫代氨基脲合成中的催化作用

IF 1.4 4区化学

Journal of the Brazilian Chemical Society Pub Date : 2023-07-24 DOI: 10.21577/0103-5053.20230030

N. Falcão, Gilvan P. Pires, Paloma Abrantes, Poliana Abrantes, João Batista M. Resende Filho, Claudio Lima Junior, E. Teotonio, J. Vale

{"title":"Magnetic Nanoparticles Based on DABCO as Catalysts in the Knoevenagel Reaction and Synthesis of Isatin-β-thiosemicarbazones","authors":"N. Falcão, Gilvan P. Pires, Paloma Abrantes, Poliana Abrantes, João Batista M. Resende Filho, Claudio Lima Junior, E. Teotonio, J. Vale","doi":"10.21577/0103-5053.20230030","DOIUrl":"https://doi.org/10.21577/0103-5053.20230030","url":null,"abstract":"This work describes the route to prepare a novel core-shell catalyst based on 1,4-diazabicyclo[2,2,2]octane (DABCO) supported magnetic nanoparticles (MNPs). The morphology and composition of the obtained catalysts were characterized by Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), quantum design vibrating sample magnetometer (VSM) and scanning electron microscopy (SEM). These nanomaterials presented high performance as a basic catalyst for Knoevenagel condensation between malononitrile and aldehydes, leading to products with excellent yields (84-99%) and short reaction times (5-60 min). Furthermore, it was also efficient in the condensation of isatins with 4-phenylthiosemicarbazide, resulting in isatin-β-thiosemicarbazones with high yields (81-94%) and short times (60-180 min). It is worth mentioning that the catalyst was recovered and reused in these two kinds of reactions after six cycles without significant yield loss.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68332689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dereplication of Sclerotiorin-Like Azaphilones Produced by Penicillium meliponae Using LC-MS/MS Analysis and Molecular Networking LC-MS/MS分析及分子网络技术对梅利蓬青霉类核蛋白氮杂啉类化合物的脱皮作用

IF 1.4 4区化学

Journal of the Brazilian Chemical Society Pub Date : 2023-07-24 DOI: 10.21577/0103-5053.20230027

E. Peres, Mayane P. Souza, T. Sousa, C. da Silva, A. Barros, F. D. da Silva, E. Costa, L. D. de Medeiros, M. Forim, A. D. de Souza, Weider H. P. Paz, G. D. da Silva, A. D. de Souza, H. Koolen

{"title":"Dereplication of Sclerotiorin-Like Azaphilones Produced by Penicillium meliponae Using LC-MS/MS Analysis and Molecular Networking","authors":"E. Peres, Mayane P. Souza, T. Sousa, C. da Silva, A. Barros, F. D. da Silva, E. Costa, L. D. de Medeiros, M. Forim, A. D. de Souza, Weider H. P. Paz, G. D. da Silva, A. D. de Souza, H. Koolen","doi":"10.21577/0103-5053.20230027","DOIUrl":"https://doi.org/10.21577/0103-5053.20230027","url":null,"abstract":"Penicillium meliponae, a recently described and rare species, was isolated as an endophytic fungus from the Amazonian plant Duguetia sthelechantha, and has been proven to be a pigment producer. Considering the high productivity of this species and the lack of data on its chemical composition, the present study aimed to characterize the chemical profile of P. meliponae and evaluate the influence of agitation and the use of different culture media. For this purpose, liquid chromatography coupled with mass spectrometry (LC-MS/MS) and molecular networking were used, allowing the identification of 17 azaphilone molecules with sclerotiorin-like skeletons, becoming the first chemical report of this species. In addition, the different production patterns in the tested culture media were indicative that this species is sensitive to changes in the composition of the carbon source and to the presence of agitation. Furthermore, this work contributes to the fragmentation mechanisms of the different possible structural arrangements for azaphilones of the sclerotiorin type and serves as a repository of information on the gas-phase behavior of this type of metabolite in mass spectrometry experiments and will assist future studies aimed at the discovery of azaphilones.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68332667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Validation of an Analytical Method by Headspace Gas Chromatography with Flame Ionization and Evaluation of Matrix Effect of Volatile Compounds in Cat Food 顶空气相色谱火焰电离分析方法的验证及猫粮中挥发性化合物基质效应的评价

IF 1.4 4区化学

Journal of the Brazilian Chemical Society Pub Date : 2023-07-24 DOI: 10.21577/0103-5053.20230026

Bruno Carvalho, Patrícia dos Santos, Geovane da Silva, C. Senes, J. Visentainer, O. Santos

{"title":"Validation of an Analytical Method by Headspace Gas Chromatography with Flame Ionization and Evaluation of Matrix Effect of Volatile Compounds in Cat Food","authors":"Bruno Carvalho, Patrícia dos Santos, Geovane da Silva, C. Senes, J. Visentainer, O. Santos","doi":"10.21577/0103-5053.20230026","DOIUrl":"https://doi.org/10.21577/0103-5053.20230026","url":null,"abstract":"This study describes the validation of a headspace gas chromatography with flame ionization (HS-GC-FID) method for the determination of propanal, pentanal, hexanal, octanal, and trans-2-nonenal originated by lipid oxidation from cat food samples, as well as the evaluation of the matrix effect in the results. This method was applied to the analysis of commercial cat food and proved to be suitable for the determination of these volatile compounds in different samples. Mean recoveries between 88 and 109% were obtained and repeatability expressed as relative standard deviation was always lower than 6.95%. The intra- and inter-assay precisions ranged from 0.44 to 20.88% and from 0.45 to 20.52%, respectively. In addition, the matrix effect of cat food samples was determined by comparing the slopes of the standard addition method, and the external calibration curve and its influences were verified. These results highlight the high potential of this method, which allows the determination of lipid oxidation products in cat food samples directly, without requiring prior sample preparation techniques.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68333104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Recent Synthetic Developments of Asymmetric Multicomponent Transformations: Strecker, Mannich, Passerini and Ugi Reactions 非对称多组分转化的合成新进展:Strecker, Mannich, Passerini和Ugi反应

IF 1.4 4区化学

Journal of the Brazilian Chemical Society Pub Date : 2023-07-24 DOI: 10.21577/0103-5053.20230082

Marcelo H R Carvalho, G. Amarante, P. D. de Castro

{"title":"Recent Synthetic Developments of Asymmetric Multicomponent Transformations: Strecker, Mannich, Passerini and Ugi Reactions","authors":"Marcelo H R Carvalho, G. Amarante, P. D. de Castro","doi":"10.21577/0103-5053.20230082","DOIUrl":"https://doi.org/10.21577/0103-5053.20230082","url":null,"abstract":"Multicomponent reactions (MCRs) are important transformations, which allow the attainment of structurally complex derivatives in a single step, starting from three or more compounds with relatively simple structures. These reactions are generally associated with the principles of green chemistry, allowing the incorporation of most (or all) atoms of the starting materials in the products (atom economy) and reducing purification steps (and, consequently, the need for solvents and waste production). For a long time, asymmetric methodologies (in special enantioselective protocols) for most multicomponent transformations remained a gap in the literature, limiting the use of these reactions to produce derivatives only as racemates or in low diastereoselectivities. Over the last two decades, a better comprehension of the mechanisms associated with these transformations allowed the development of efficient enantio- and diastereoselective procedures, attracting the interest of both academia and industry. In this review, selected examples of four important multicomponent reactions (Strecker, Mannich, Passerini and Ugi) will be discussed, presenting a general overview of the development of this field and pointing out possible advantages and limitations of the above mentioned methodologies. In some cases, discussions around mechanisms, proposed transition states and activation modes will be detailed disclosed.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68338807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Application of Disposable Pipette Extraction for Determination of Yb by High‑Resolution Continuum Source Graphite Furnace Atomic Absorption Spectrometry Using Lanthanum as a Chemical Modifier 以镧为化学改性剂的一次性移液管萃取法在高分辨连续源石墨炉原子吸收光谱法测定镱中的应用

IF 1.4 4区化学

Journal of the Brazilian Chemical Society Pub Date : 2023-07-24 DOI: 10.21577/0103-5053.20230021

Diogo M. Betiolo, Heloisa R. Cadorim, E. Carasek, Tatiane Maranhão

{"title":"Application of Disposable Pipette Extraction for Determination of Yb by High‑Resolution Continuum Source Graphite Furnace Atomic Absorption Spectrometry Using Lanthanum as a Chemical Modifier","authors":"Diogo M. Betiolo, Heloisa R. Cadorim, E. Carasek, Tatiane Maranhão","doi":"10.21577/0103-5053.20230021","DOIUrl":"https://doi.org/10.21577/0103-5053.20230021","url":null,"abstract":"The use of extraction technique with disposable tips (DPX) was applied for the first time for the extraction and preconcentration of Yb in samples of liquid waste from the petrochemical industry and environmental water using bioabsorbent cork. The use of cork as an extracting phase in the determination of Yb by high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS) was evaluated. The pyrolysis and atomization temperatures were optimized at 1400 and 2400 ºC, respectively. H2SO4, HNO3 and HCl acids were compared in the steps of cleaning the extraction phase and desorption of the analyte by DPX. The best extraction in the selected conditions was obtained with pH 8.0 and 5% v/v HCl. The recoveries were close to 100% for residual water and drinking water, 33 to 77% for produced water and 64 to 93% for river water. Tests with interfering ions in different concentrations were performed. The relative limit of quantification (LOQ) and limit of detection (LOD) were estimated at 0.03 and 0.01 µg L-1, respectively. The total time for the preparation of the samples by DPX was close to 1 min per sample. Extraction and pre-concentration were observed using DPX with a preenrichment factor of approximately 4 times.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68329849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Warmingins A, B and C, Three New Furofuran Lignans from Aristolochia warmingii Mast. (Aristolochiaceae) 马兜铃属植物中3种新的呋喃木脂素A、B、C。(马兜铃科)

IF 1.4 4区化学

Journal of the Brazilian Chemical Society Pub Date : 2023-07-24 DOI: 10.21577/0103-5053.20230019

C. Cunha, Paulo Vinícius de Antonio, Maria do Carmo Gomes Lustosa, Á. Cruz, J. Holzbach, D. Pereira, Isabele R. Nascimento

引用次数: 0

Corrosion Electrochemical Behavior of 2024 Aluminum Alloy in Potassium Acetate Deicing Fluid 2024铝合金在醋酸钾除冰液中的腐蚀电化学行为

IF 1.4 4区化学

Journal of the Brazilian Chemical Society Pub Date : 2023-07-24 DOI: 10.21577/0103-5053.20230024

Lin Xiuzhou, Zhuo Wei, Yang Feng, Yang Han, P. Qiang, Mei Yongjun, Wang Yuhao, Dou Baojie

引用次数: 1

Larvicidal Activity of Calcium Alginate Microcapsules Containing Clove Essential Oil Obtained by Microfluidics 丁香精油海藻酸钙微胶囊的杀幼虫活性研究

IF 1.4 4区化学

Journal of the Brazilian Chemical Society Pub Date : 2023-07-24 DOI: 10.21577/0103-5053.20230029

D. Conde, L. Mendes, Guilherme Ramos, Rafael G. Silva, Á. Teixeira, R. Teixeira, Gustavo Martins, C. Cerceau, R. Lopes

{"title":"Larvicidal Activity of Calcium Alginate Microcapsules Containing Clove Essential Oil Obtained by Microfluidics","authors":"D. Conde, L. Mendes, Guilherme Ramos, Rafael G. Silva, Á. Teixeira, R. Teixeira, Gustavo Martins, C. Cerceau, R. Lopes","doi":"10.21577/0103-5053.20230029","DOIUrl":"https://doi.org/10.21577/0103-5053.20230029","url":null,"abstract":"Essential oils (EO) have diverse applications, such as antibacterial and antifungal activity. However, they are susceptible to oxidation in the presence of air, light, and moisture. In addition, they are thermally unstable. In this sense, it is necessary to develop techniques to increase the lifespan of EO. In this work, EO was obtained from cloves and characterized by different techniques. The major compounds found were eugenol (83%), eugenol acetate (9%), and β-caryophyllene (8%). The EO was encapsulated by extrusion using a microfluidic device. The sodium alginate was used as wall material, and the CaCl2 solution was used as a crosslinking agent. The microcapsule presented sizes of 164.7 ± 0.3 µm, with an encapsulation yield of 64 ± 14%. Functional characteristic groups of EO were observed in the microcapsule by infrared and Raman spectroscopies. The microcapsule increased the thermal decomposition of the EO from 162 to 230 °C. Release kinetics of the capsule was performed, with an equilibrium time of 72 h and release of 54% of the EO. Finally, the pure EO and encapsulated EO-microcapsules were applied in the Aedes aegypti larvae control, showing mean lethal concentration necessary to eliminate 50% (LC50) values of 74.4 and 96.9 µg mL-1 and lethal concentration necessary to eliminate 90% (LC90) of 106.2 and 133.3 µg mL-1 for pure EO and encapsulated EO, respectively. Therefore, it was concluded that these microcapsules have the potential for application in the Aedes aegypti larvae control.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68332680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

COVID-19 Infection Changes the Functions and Morphology of Erythrocytes: A Multidisciplinary Study COVID-19感染改变红细胞功能和形态:一项多学科研究

IF 1.4 4区化学

Journal of the Brazilian Chemical Society Pub Date : 2023-07-24 DOI: 10.21577/0103-5053.20230031

Marcos V. S. Sales, E. Tanabe, T. Maciel, M. Tavares, Juliana Leal, L. Pinto, Keyla S. N. Pires, Jorge Coelho, E. Silva, Samuel Souza, E. Fonseca, Thiago Fragoso, Thiago Aquino, A. Borbely, U. Rocha, Josué Santos, A. C. Leite

{"title":"COVID-19 Infection Changes the Functions and Morphology of Erythrocytes: A Multidisciplinary Study","authors":"Marcos V. S. Sales, E. Tanabe, T. Maciel, M. Tavares, Juliana Leal, L. Pinto, Keyla S. N. Pires, Jorge Coelho, E. Silva, Samuel Souza, E. Fonseca, Thiago Fragoso, Thiago Aquino, A. Borbely, U. Rocha, Josué Santos, A. C. Leite","doi":"10.21577/0103-5053.20230031","DOIUrl":"https://doi.org/10.21577/0103-5053.20230031","url":null,"abstract":"Hematological problems are associated with Coronavirus disease 2019 (COVID-19). Respiratory impairment is the higher point studied, although without experimental studies related to the oxygen transport performed by erythrocytes. Therefore, we decided to investigate if erythrocytes from COVID-19 patients have their functionality changed. The case-control study included hospitalized patients with a positive real-time polymerase chain reaction (RT-PCR) result admitted to University Hospital. Volunteers (negative RT-PCR results) were recruited as a control group. Thus, we assessed different erythrocytes parameters, oxidative stress markers, and biophysical studies using whole blood and isolated hemoglobin. We found a decrease of 51% in oxygen uptake and reduced antioxidant enzyme activity in COVID-19 patients compared to controls. Raman spectrometry showed structural changes in the hemoglobin and lipids of the erythrocytes from COVID-19 patients; thus, these results were consolidated with an increase in Young’s modulus in erythrocytes followed by morphology changes. Besides, isolated hemoglobin from COVID-19 patients has a distinct interaction profile using a ligand model compared to the control. COVID-19 leads to structural, functional, and morphological damage to human erythrocytes. Our data showed structural and molecular changes and induction of oxidative stress in erythrocytes by COVID-19, a new perspective on the contribution of erythrocytes to a respiratory commitment in COVID-19.","PeriodicalId":17257,"journal":{"name":"Journal of the Brazilian Chemical Society","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68332733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Hybrid Molecularly Imprinted Polymer for Selective Adsorption of Urinary S-Phenylmercapturic Acid 一种用于选择性吸附尿S-苯巯基尿酸的杂化分子印迹聚合物

IF 1.4 4区化学

Journal of the Brazilian Chemical Society Pub Date : 2023-07-24 DOI: 10.21577/0103-5053.20230032

Rafaela Gomes, Marina Tonucci, M. Prete, C. Tarley, B. Baeta, R. Afonso

引用次数: 0