Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
 
 
Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

Article Types

Countries / Regions

Search Results (38)

Search Parameters:
Keywords = aryl ureas

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
17 pages, 2451 KiB  
Article
Design, Synthesis and Biological Assessment of N′-(2-Oxoindolin-3-ylidene)-6-methylimidazo[2,1-b]thiazole-5-carbohydrazides as Potential Anti-Proliferative Agents toward MCF-7 Breast Cancer
by Najla A. Alshaye, Mohamed K. Elgohary, Mahmoud S. Elkotamy and Hatem A. Abdel-Aziz
Pharmaceuticals 2024, 17(2), 216; https://doi.org/10.3390/ph17020216 - 7 Feb 2024
Cited by 2 | Viewed by 1127
Abstract
Breast cancer is a serious threat to the health and lives of women. Two novel series of N′-(2-oxoindolin-3-ylidene)-6-methylimidazo[2,1-b]thiazole-5-carbohydrazides and 1-(aryl)-3-(6-methylimidazo[2,1-b]thiazol-5-yl)ureas were designed, synthesized and investigated for their anticancer efficacy against the MCF-7 breast cell line. Three compounds of [...] Read more.
Breast cancer is a serious threat to the health and lives of women. Two novel series of N′-(2-oxoindolin-3-ylidene)-6-methylimidazo[2,1-b]thiazole-5-carbohydrazides and 1-(aryl)-3-(6-methylimidazo[2,1-b]thiazol-5-yl)ureas were designed, synthesized and investigated for their anticancer efficacy against the MCF-7 breast cell line. Three compounds of the first series showed potent activity toward MCF-7 with IC50 in the range 8.38–11.67 µM, respectively, as compared to Sorafenib (IC50 = 7.55 µM). N′-(1-butyl-2-oxoindolin-3-ylidene)-6-methylimidazo[2,1-b]thiazole-5-carbohydrazide inhibited VEGFR-2 with IC50 = 0.33 µM when compared with Sorafenib (IC50 = 0.09 µM). Furthermore, this compound was introduced to PCR assessment, where it increased Bax, caspase 8, caspase 9 and cytochrome C levels by 4.337-, 2.727-, 4.947- and 2.420-fold, respectively, while it decreased levels of Bcl-2, as the anti-apoptotic gene, by 0.359-fold when compared to the untreated control MCF-7. This compound was also arrested in the G2/M phase by 27.07%, compared with 11.31% for the control MCF-7. Furthermore, it induced early and late apoptosis in MCF-7. In addition, a molecular docking study in the VEGFR-2 active site was performed to assess the binding profile for the most active compounds. Moreover, ADME parameters of the targeted compounds were also evaluated. Full article
Show Figures

Graphical abstract

15 pages, 8995 KiB  
Article
Novel 1-(1-Arylimiazolin-2-Yl)-3-Arylalkilurea Derivatives with Modulatory Activity on Opioid MOP Receptors
by Dominik Straszak, Sylwia Woźniak, Agata Siwek, Monika Głuch-Lutwin, Marcin Kołaczkowski, Aldona Pietrzak, Bartłomiej Drop and Dariusz Matosiuk
Molecules 2024, 29(3), 571; https://doi.org/10.3390/molecules29030571 - 24 Jan 2024
Viewed by 1188
Abstract
μ-opioid receptor ligands such as morphine and fentanyl are the most known and potent painkillers. However, the severe side effects seen with their use significantly limit their widespread use. The continuous broadening of knowledge about the properties of the interactions of the MOP [...] Read more.
μ-opioid receptor ligands such as morphine and fentanyl are the most known and potent painkillers. However, the severe side effects seen with their use significantly limit their widespread use. The continuous broadening of knowledge about the properties of the interactions of the MOP receptor (human mu opioid receptor, OP3) with ligands and specific intracellular signaling pathways allows for the designation of new directions of research with respect to compounds with analgesic effects in a mechanism different from classical ligands. Allosteric modulation is an extremely promising line of research. Compounds with modulator properties may provide a safer alternative to the currently used opioids. The aim of our research was to obtain a series of urea derivatives of 1-aryl-2-aminoimidazoline and to determine their activity, mechanism of biological action and selectivity toward the MOP receptor. The obtained compounds were subjected to functional tests (cAMP accumulation and β-arrestin recruitment) in vitro. One of the obtained compounds, when administered alone, did not show any biological activity, while when co-administered with DAMGO, it inhibited β-arrestin recruitment. These results indicate that this compound is a negative allosteric modulator (NAM) of the human MOP receptor. Full article
(This article belongs to the Special Issue Progress in the Treatment of CNS Disorders: From In Silico to In Vivo)
Show Figures

Figure 1

19 pages, 4233 KiB  
Article
An Efficient Synthesis of 1-(1,3-Dioxoisoindolin-2-yl)-3-aryl Urea Analogs as Anticancer and Antioxidant Agents: An Insight into Experimental and In Silico Studies
by Obaid Afzal and Mohamed Jawed Ahsan
Molecules 2024, 29(1), 67; https://doi.org/10.3390/molecules29010067 - 21 Dec 2023
Viewed by 1178
Abstract
The present investigation reports the efficient multistep synthesis of 1-(1,3-dioxoisoindolin-2-yl)-3-aryl urea analogs (7af) in good yields. All the 1-(1,3-dioxoisoindolin-2-yl)-3-aryl urea analogs (7af) were characterized by spectroscopic techniques. Five among the six compounds were tested against [...] Read more.
The present investigation reports the efficient multistep synthesis of 1-(1,3-dioxoisoindolin-2-yl)-3-aryl urea analogs (7af) in good yields. All the 1-(1,3-dioxoisoindolin-2-yl)-3-aryl urea analogs (7af) were characterized by spectroscopic techniques. Five among the six compounds were tested against 56 cancer cell lines at 10 µM as per the standard protocol. 1-(4-Bromophenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7c) exhibited moderate but significant anticancer activity against EKVX, CAKI-1, UACC-62, MCF7, LOX IMVI, and ACHN with percentage growth inhibitions (PGIs) of 75.46, 78.52, 80.81, 83.48, 84.52, and 89.61, respectively. Compound 7c was found to exhibit better anticancer activity than thalidomide against non-small cell lung, CNS, melanoma, renal, prostate, and breast cancer cell lines. It was also found to exhibit superior anticancer activity against melanoma cancer compared to imatinib. Among the tested compounds, the 4-bromosubstitution (7c) on the phenyl ring demonstrated good anticancer activity. Docking scores ranging from −6.363 to −7.565 kcal/mol were observed in the docking studies against the molecular target EGFR. The ligand 7c displayed an efficient binding against the EGFR with a docking score of −7.558 kcal/mol and displayed an H-bond interaction with Lys745 and the carbonyl functional group. Compound 7c demonstrated a moderate inhibition of EGFR with an IC50 of 42.91 ± 0.80 nM, in comparison to erlotinib (IC50 = 26.85 ± 0.72 nM), the standard drug. The antioxidant potential was also calculated for the compounds (7af), which exhibited good to low activity. 1-(2-Methoxyphenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7f) and 1-(4-Methoxyphenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7d) demonstrated significant antioxidant activity with IC50 values of 15.99 ± 0.10 and 16.05 ± 0.15 µM, respectively. The 2- and 4-methoxysubstitutions on the N-phenyl ring showed good antioxidant activity among the series of compounds (7af). An in silico ADMET prediction studies showed the compounds’ adherence to Lipinski’s rule of five: they were free from toxicities, including mutagenicity, cytotoxicity, and immunotoxicity, but not for hepatotoxicity. The toxicity prediction demonstrated LD50 values between 1000 and 5000 mg/Kg, putting the compounds either in class IV or class V toxicity classes. Our findings might create opportunities for more advancements in cancer therapeutics. Full article
(This article belongs to the Section Organic Chemistry)
Show Figures

Figure 1

19 pages, 3737 KiB  
Article
Repurposing Study of 4-Acyl-1-phenylaminocarbonyl-2-substituted-piperazine Derivatives as Potential Anticancer Agents—In Vitro Evaluation against Breast Cancer Cells
by Emilio Guillén-Mancina, María del Rosario García-Lozano, Estefanía Burgos-Morón, Sarah Mazzotta, Pablo Martínez-Aguado, José Manuel Calderón-Montaño, José Manuel Vega-Pérez, Miguel López-Lázaro, Fernando Iglesias-Guerra and Margarita Vega-Holm
Int. J. Mol. Sci. 2023, 24(23), 17041; https://doi.org/10.3390/ijms242317041 - 1 Dec 2023
Cited by 1 | Viewed by 1229
Abstract
Breast cancer is the most common type of cancer in women. Although current treatments can increase patient survival, they are rarely curative when the disease is advanced (metastasis). Therefore, there is an urgent need to develop new cytotoxic drugs with a high selectivity [...] Read more.
Breast cancer is the most common type of cancer in women. Although current treatments can increase patient survival, they are rarely curative when the disease is advanced (metastasis). Therefore, there is an urgent need to develop new cytotoxic drugs with a high selectivity toward cancer cells. Since repurposing approved drugs for cancer therapy has been a successful strategy in recent years, in this study, we screened a library of antiviral piperazine-derived compounds as anticancer agents. The compounds included a piperazine ring and aryl urea functions, which are privileged structures present in several anti-breast cancer drugs. The selective cytotoxic activity of a set of thirty-four 4-acyl-2-substituted piperazine urea derivatives against MCF7 breast cancer cells and MCF 10A normal breast cells was determined. Compounds 31, 32, 35, and 37 showed high selective anticancer activity against breast cancer cells and were also tested against another common type of cancer, non-small cell lung cancer (A549 lung cancer cells versus MRC-5 lung normal cells). Compounds 35 and 37 also showed selectivity against lung cancer cells. These results suggest that compounds 35 and 37 may be promising hit compounds for the development of new anticancer agents. Full article
(This article belongs to the Special Issue Novel Molecular Pathways in Oncology)
Show Figures

Figure 1

21 pages, 7099 KiB  
Article
Photocatalytic Synthesis of Coumarin Derivatives Using Visible-Light-Responsive Strawberry Dye-Sensitized Titanium Dioxide Nanoparticles
by Mshari A. Alotaibi, Abdulrahman I. Alharthi, Talal F. Qahtan, Satam Alotibi, Amani M. Alansi and Md. Afroz Bakht
Nanomaterials 2023, 13(23), 3001; https://doi.org/10.3390/nano13233001 - 22 Nov 2023
Viewed by 1233
Abstract
This study presents a novel method for the photocatalytic synthesis of 4-aryl-6-(3-coumarinyl) pyrimidin-2 (1H)-ones (a coumarin derivative) using strawberry dye-sensitized TiO2 (SD-TiO2) under visible light. The synthesis of 4-aryl-6-(3-coumarinyl) pyrimidin-2 (1H)-ones was achieved through a three-component, one-pot condensation reaction involving [...] Read more.
This study presents a novel method for the photocatalytic synthesis of 4-aryl-6-(3-coumarinyl) pyrimidin-2 (1H)-ones (a coumarin derivative) using strawberry dye-sensitized TiO2 (SD-TiO2) under visible light. The synthesis of 4-aryl-6-(3-coumarinyl) pyrimidin-2 (1H)-ones was achieved through a three-component, one-pot condensation reaction involving 3-acetyl coumarin, aldehydes, and urea, utilizing SD-TiO2 as a reusable and innovative photocatalyst at room temperature. The resulting SD-TiO2 photocatalyst was thoroughly characterized using FT-IR, XPS, XRD, SEM, and BET. The efficacy of SD-TiO2 was evaluated by comparing it to pristine TiO2 in terms of photocatalytic activity, and the optimal conditions for the synthesis process were determined. Notably, the SD-TiO2 photocatalyst exhibited a maximum yield of the compound, reaching up to 96% in just 30 min with a catalyst concentration of 1 mg/mL. This yield surpasses traditional thermal procedures employing reflux conditions, where 1 mg/mL of SD-TiO2 is sufficient to complete the reaction. The resulting 4-aryl-6-(3-coumarinyl) pyrimidin-2 (1H)-ones were further characterized using 1H-NMR and 13C-NMR. Moreover, the stability of the SD-TiO2 photocatalyst was confirmed through recyclability experiments and spectroscopic characterization, demonstrating its practicality for up to three consecutive reaction cycles. Full article
(This article belongs to the Special Issue Advanced Nanomaterials for Photocatalysis)
Show Figures

Figure 1

14 pages, 1124 KiB  
Article
Unveiling the Potential of BenzylethyleneAryl–Urea Scaffolds for the Design of New Onco Immunomodulating Agents
by Raquel Gil-Edo, Santiago Royo, Miguel Carda and Eva Falomir
Pharmaceuticals 2023, 16(6), 808; https://doi.org/10.3390/ph16060808 - 29 May 2023
Cited by 1 | Viewed by 1323
Abstract
This work focuses on the development of thirteen benzylethylenearyl ureas and one carbamate. After the synthesis and purification of the compounds, we studied their antiproliferative action on cell lines, such as HEK-293, and cancer ones, such as HT-29, MCF-7 or A-549, on the [...] Read more.
This work focuses on the development of thirteen benzylethylenearyl ureas and one carbamate. After the synthesis and purification of the compounds, we studied their antiproliferative action on cell lines, such as HEK-293, and cancer ones, such as HT-29, MCF-7 or A-549, on the immune Jurkat T-cells and endothelial cells HMEC-1. Compounds C.1, C.3, C.12 and C.14 were selected for further biological studies to establish their potential as immunomodulating agents. Some of the derivatives exhibited significant inhibitory effects on both targets: PD-L1 and VEGFR-2 in the HT-29 cell line, showing that urea C.12 is active against both targets. Some compounds could inhibit more than 50% of cancer cell proliferation compared to non-treated ones when assessed in co-cultures using HT-29 and THP-1 cells. In addition, they significantly reduced CD11b expression, which is a promising target for immune modulation in anticancer immunotherapies. Full article
(This article belongs to the Section Medicinal Chemistry)
Show Figures

Graphical abstract

16 pages, 2535 KiB  
Article
Exploring BenzylethoxyAryl Urea Scaffolds for Multitarget Immunomodulation Therapies
by Raquel Gil-Edo, German Hernández-Ribelles, Santiago Royo, Natasha Thawait, Alan Serrels, Miguel Carda and Eva Falomir
Int. J. Mol. Sci. 2023, 24(10), 8582; https://doi.org/10.3390/ijms24108582 - 11 May 2023
Cited by 1 | Viewed by 1703
Abstract
Thirteen benzylethoxyaryl ureas have been synthesized and biologically evaluated as multitarget inhibitors of VEGFR-2 and PD-L1 proteins to overcome resistance phenomena offered by cancer. The antiproliferative activity of these molecules on several tumor cell lines (HT-29 and A549), on the endothelial cell line [...] Read more.
Thirteen benzylethoxyaryl ureas have been synthesized and biologically evaluated as multitarget inhibitors of VEGFR-2 and PD-L1 proteins to overcome resistance phenomena offered by cancer. The antiproliferative activity of these molecules on several tumor cell lines (HT-29 and A549), on the endothelial cell line HMEC-1, on immune cells (Jurkat T) and on the non-tumor cell line HEK-293 has been determined. Selective indexes (SI) have been also determined and compounds bearing p-substituted phenyl urea unit together with a diaryl carbamate exhibited high SI values. Further studies on these selected compounds to determine their potential as small molecule immune potentiators (SMIPs) and as antitumor agents have been performed. From these studies, we have concluded that the designed ureas have good tumor antiangiogenic properties, exhibit good inhibition of CD11b expression, and regulate pathways involved in CD8 T-cell activity. These properties suggest that these compounds could be potentially useful in the development of new cancer immune treatments. Full article
(This article belongs to the Section Molecular Oncology)
Show Figures

Graphical abstract

16 pages, 2026 KiB  
Article
Synthesis of 3-(Pyridin-2-yl)quinazolin-2,4(1H,3H)-diones via Annulation of Anthranilic Esters with N-pyridyl Ureas
by Svetlana O. Baykova, Kirill K. Geyl, Sergey V. Baykov and Vadim P. Boyarskiy
Int. J. Mol. Sci. 2023, 24(8), 7633; https://doi.org/10.3390/ijms24087633 - 21 Apr 2023
Cited by 5 | Viewed by 1459
Abstract
A new route for the synthesis of quinazolin-2,4(1H,3H)-diones and thieno [2,3-d]pyrimidine-2,4(1H,3H)-diones substituted by pyridyl/quinolinyl moiety in position 3 has been developed. The proposed method concluded in an annulation of substituted anthranilic esters or [...] Read more.
A new route for the synthesis of quinazolin-2,4(1H,3H)-diones and thieno [2,3-d]pyrimidine-2,4(1H,3H)-diones substituted by pyridyl/quinolinyl moiety in position 3 has been developed. The proposed method concluded in an annulation of substituted anthranilic esters or 2-aminothiophene-3-carboxylates with 1,1-dimethyl-3-(pyridin-2-yl) ureas. The process consists of the formation of N-aryl-N′-pyridyl ureas followed by their cyclocondensation into the corresponding fused heterocycles. The reaction does not require the use of metal catalysts and proceeds with moderate to good yields (up to 89%). The scope of the method is more than 30 examples, including compounds with both electron-withdrawing and electron-donating groups, as well as diverse functionalities. At the same time, strong electron-acceptor substituents in the pyridine ring of the starting ureas reduce the product yield or even prevent the cyclocondensation step. The reaction can be easily scaled to gram quantities. Full article
(This article belongs to the Section Physical Chemistry and Chemical Physics)
Show Figures

Figure 1

13 pages, 5356 KiB  
Article
Phytoactive Aryl Carbamates and Ureas as Cytokinin-like Analogs of EDU
by Maxim S. Oshchepkov, Leonid V. Kovalenko, Antonida V. Kalistratova, Inna N. Solovieva, Marina A. Tsvetikova, Olga N. Gorunova, Nataliya A. Bystrova and Konstantin A. Kochetkov
Agronomy 2023, 13(3), 778; https://doi.org/10.3390/agronomy13030778 - 7 Mar 2023
Cited by 2 | Viewed by 1186
Abstract
Ureas, carbamates and oxamates are rather common structural motifs. They are present in both natural and synthetic compounds that exhibit a wide spectrum of biological activity. These derivatives of carbonic and oxalic acids are regularly employed as the basic structural elements in hybrid [...] Read more.
Ureas, carbamates and oxamates are rather common structural motifs. They are present in both natural and synthetic compounds that exhibit a wide spectrum of biological activity. These derivatives of carbonic and oxalic acids are regularly employed as the basic structural elements in hybrid molecule synthesis, as well as in organic synthesis in general. A series of unsymmetrical hybrid compounds (E1–E4) has been synthesized, with core imidazolidin-2-one and aryl moieties as urea and carbamate derivatives. Plant growth regulatory activity of these compounds was studied with respect to their influence on germination, growth and development of wheat (Triticum aestivum L.) seeds in laboratory and field tests. Their effect on drought resistance concentrations as low as 4 × 10−7 M was established. Compounds E1 and E4 have shown higher growth-regulating activity than standard thidiazuron and CCC. Full article
(This article belongs to the Section Plant-Crop Biology and Biochemistry)
Show Figures

Figure 1

13 pages, 7168 KiB  
Article
Design and Synthesis of New Acyl Urea Analogs as Potential σ1R Ligands
by Rajesh Thapa, Rafael Flores, Kwan H. Cheng, Bereket Mochona and Donald Sikazwe
Molecules 2023, 28(5), 2319; https://doi.org/10.3390/molecules28052319 - 2 Mar 2023
Cited by 2 | Viewed by 2236
Abstract
In search of synthetically accessible open-ring analogs of PD144418 or 5-(1-propyl-1,2,5,6-tetrahydropyridin-3-yl)-3-(p-tolyl)isoxazole, a highly potent sigma-1 receptor (σ1R) ligand, we herein report the design and synthesis of sixteen arylated acyl urea derivatives. Design aspects included modeling the target compounds for drug-likeness, docking at σ1R [...] Read more.
In search of synthetically accessible open-ring analogs of PD144418 or 5-(1-propyl-1,2,5,6-tetrahydropyridin-3-yl)-3-(p-tolyl)isoxazole, a highly potent sigma-1 receptor (σ1R) ligand, we herein report the design and synthesis of sixteen arylated acyl urea derivatives. Design aspects included modeling the target compounds for drug-likeness, docking at σ1R crystal structure 5HK1, and contrasting the lower energy molecular conformers with that of the receptor-embedded PD144418—a molecule we opined that our compounds could mimic pharmacologically. Synthesis of our acyl urea target compounds was achieved in two facile steps which involved first generating the N-(phenoxycarbonyl) benzamide intermediate and then coupling it with the appropriate amines weakly to strongly nucleophilic amines. Two potential leads (compounds 10 and 12, with respective in vitro σ1R binding affinities of 2.18 and 9.54 μM) emerged from this series. These leads will undergo further structure optimization with the ultimate goal of developing novel σ1R ligands for testing in neurodegeneration models of Alzheimer’s disease (AD). Full article
(This article belongs to the Special Issue Research of Organic Chemicals for Biological Applications)
Show Figures

Figure 1

13 pages, 3546 KiB  
Review
Diarylureas: New Promising Small Molecules against Streptococcus mutans for the Treatment of Dental Caries
by Domenico Iacopetta, Jessica Ceramella, Alessia Catalano, Assunta D’Amato, Graziantonio Lauria, Carmela Saturnino, Inmaculada Andreu, Pasquale Longo and Maria Stefania Sinicropi
Antibiotics 2023, 12(1), 112; https://doi.org/10.3390/antibiotics12010112 - 7 Jan 2023
Cited by 8 | Viewed by 3955
Abstract
Dental caries is a biofilm-mediated disease that represents a worldwide oral health issue. Streptococcus mutans has been ascertained as the main cariogenic pathogen responsible for human dental caries, with a high ability to form biofilms, regulated by the quorum sensing. Diarylureas represent a [...] Read more.
Dental caries is a biofilm-mediated disease that represents a worldwide oral health issue. Streptococcus mutans has been ascertained as the main cariogenic pathogen responsible for human dental caries, with a high ability to form biofilms, regulated by the quorum sensing. Diarylureas represent a class of organic compounds that show numerous biological activities, including the antimicrobial one. Two small molecules belonging to this class, specifically to diphenylureas, BPU (1,3-bis[3,5-bis(trifluoromethyl)phenyl]urea) and DMTU (1,3-di-m-tolyl-urea), showed interesting results in studies regarding the antimicrobial activity against the cariogenic bacterium S. mutans. Since there are not many antimicrobials used for the prevention and treatment of caries, further studies on these two interesting compounds and other diarylureas against S. mutans may be useful to design new effective agents for the treatment of caries with generally low cytotoxicity. Full article
(This article belongs to the Special Issue Searching for Small Molecules as Antimicrobials)
Show Figures

Graphical abstract

9 pages, 838 KiB  
Short Note
1-[2-(1H-Pyrrole-2-carbonyl)phenyl]-3-(4-methoxyphenyl)urea
by Antonia G. Sarantou and George Varvounis
Molbank 2023, 2023(1), M1531; https://doi.org/10.3390/M1531 - 22 Dec 2022
Viewed by 1891
Abstract
For the synthesis of 1-(2-(1H-pyrrole-2-carbonyl)phenyl)-3-(4-methoxyphenyl)urea, the final product, two different methods were used, in one or two steps, from (2-aminophenyl)(1H-pyrrol-2-yl)methanone. The one-step synthesis entailed a carbonylation reaction with 1/3 equivalent of triphosgene in the presence of two equivalents of [...] Read more.
For the synthesis of 1-(2-(1H-pyrrole-2-carbonyl)phenyl)-3-(4-methoxyphenyl)urea, the final product, two different methods were used, in one or two steps, from (2-aminophenyl)(1H-pyrrol-2-yl)methanone. The one-step synthesis entailed a carbonylation reaction with 1/3 equivalent of triphosgene in the presence of two equivalents of trimethylamine, followed by the addition of 4-methoxyaniline to the in situ generated aryl isocyanate. The two-step synthesis required first the preparation of phenyl(2-(1H-pyrrole-2-carbonyl)phenyl)carbamate and then a substitution reaction by 4-methoxyaniline. The first method produced the final product in 72% yield, which was the best yield. The structure of the final product was confirmed by FTIR, UV-VIS, 1H and 13C NMR spectroscopy and high resolution mass spectrometry. Full article
(This article belongs to the Collection Heterocycle Reactions)
Show Figures

Figure 1

13 pages, 1161 KiB  
Article
Urea Synthesis from Isocyanides and O-Benzoyl Hydroxylamines Catalyzed by a Copper Salt
by Ning Yu, Jing-Fang Lv, Shi-Mei He, Yanyan Cui, Ye Wei and Kun Jiang
Molecules 2022, 27(23), 8219; https://doi.org/10.3390/molecules27238219 - 25 Nov 2022
Viewed by 1499
Abstract
In the presence of CuOAc, a series of unsymmetric ureas can be generated in moderate to good yields under mild reaction conditions (10 mol% of CuOAc, 2 equiv t-BuONa or PhONa, 30 °C), using aryl isocyanides and O-benzoyl hydroxylamines as the [...] Read more.
In the presence of CuOAc, a series of unsymmetric ureas can be generated in moderate to good yields under mild reaction conditions (10 mol% of CuOAc, 2 equiv t-BuONa or PhONa, 30 °C), using aryl isocyanides and O-benzoyl hydroxylamines as the readily accessible starting materials. The reactions might undergo a cascade process involving isocyanide insertion into the N-O bond and Mumm-type rearrangement. This work represents a rare example of isocyanide insertion into N-O bonds, which would extend isocyanide insertion chemistry. Full article
(This article belongs to the Special Issue Advances on the Application of N-O Bond Compounds)
Show Figures

Scheme 1

12 pages, 3634 KiB  
Article
Physically and Chemically Stable Anion Exchange Membranes with Hydrogen-Bond Induced Ion Conducting Channels
by Chengpeng Wei, Weisheng Yu, Liang Wu, Xiaolin Ge and Tongwen Xu
Polymers 2022, 14(22), 4920; https://doi.org/10.3390/polym14224920 - 15 Nov 2022
Cited by 14 | Viewed by 2684
Abstract
Anion exchange membranes (AEMs) with desirable properties are the crucial components for numerous energy devices such as AEM fuel cells (AEMFCs), AEM water electrolyzers (AEMWEs), etc. However, the lack of suitable AEMs severely limits the performance of devices. Here, a series of physically [...] Read more.
Anion exchange membranes (AEMs) with desirable properties are the crucial components for numerous energy devices such as AEM fuel cells (AEMFCs), AEM water electrolyzers (AEMWEs), etc. However, the lack of suitable AEMs severely limits the performance of devices. Here, a series of physically and chemically stable AEMs have been prepared by the reaction between the alkyl bromine terminal ether-bond-free aryl backbone and the urea group-containing crosslinker. Morphology analyses confirm that the hydrogen bonding interaction between urea groups is capable of driving the ammonium cations to aggregate and further form continuous ion-conducting channels. Therefore, the resultant AEM demonstrates remarkable OH conductivity (59.1 mS cm−1 at 30 °C and 122.9 mS cm−1 at 90 °C) despite a moderate IEC (1.77 mmol g−1). Simultaneously, due to the adoption of ether-bond-free aryl backbone and alkylene chain-modified trimethylammonium cation, the AEM possesses excellent alkaline stability (87.3% IEC retention after soaking in 1 M NaOH for 1080 h). Moreover, the prepared AEM shows desirable mechanical properties (tensile stress > 25 MPa) and dimensional stability (SR = 20.3% at 90 °C) contributed by the covalent-bond and hydrogen-bond crosslinking network structures. Moreover, the resulting AEM reaches a peak power density of 555 mW cm−2 in an alkaline H2/O2 single fuel cell at 70 °C without back pressure. This rational structural design presented here provides inspiration for the development of high-performance AEMs, which are crucial for membrane technologies. Full article
(This article belongs to the Special Issue Polymers for Electrochemical Applications)
Show Figures

Figure 1

5 pages, 372 KiB  
Proceeding Paper
Modified Algar–Flynn–Oyamada Reaction for the Synthesis of 3-Hydroxy-2-styryl-chromen-4-ones under Solvent-Free Conditions
by Dinesh Kumar
Chem. Proc. 2022, 12(1), 27; https://doi.org/10.3390/ecsoc-26-13558 - 14 Nov 2022
Viewed by 1374
Abstract
The simple and efficient conditions for a Algar–Flynn–Oyamada reaction for the synthesis of 3-hydroxy-2-styryl-chromen-4-ones involving the grinding of different 1-(2′-hydroxy-phenyl)-5-aryl-penta-2,4-dien-1-ones with UHP (urea–hydrogen peroxide), pulverized potassium hydroxide and a few drops of ethanol at room temperature under solvent-free conditions are described. A presented [...] Read more.
The simple and efficient conditions for a Algar–Flynn–Oyamada reaction for the synthesis of 3-hydroxy-2-styryl-chromen-4-ones involving the grinding of different 1-(2′-hydroxy-phenyl)-5-aryl-penta-2,4-dien-1-ones with UHP (urea–hydrogen peroxide), pulverized potassium hydroxide and a few drops of ethanol at room temperature under solvent-free conditions are described. A presented protocol offers a faster reaction and a higher yield compared to conventional methods. The structure of the synthesized compounds was identified from their spectral data (IR, 1H-NMR). Full article
Show Figures

Scheme 1

Back to TopTop