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991.
Monica Nardi Sonia Bonacci Natividad Herrera Cano Manuela Oliverio Antonio Procopio 《Molecules (Basel, Switzerland)》2022,27(5)
The benzimidazole ring of the heterocyclic pharmacophores is one of the most widespread and studied systems in nature. The benzimidazole derivative synthesis study is a crucial point for the development of a clinically available benzimidazole-based drug. Here, we report a simple microwave assisted method for the synthesis of 1,2-disubstituted benzimidazoles. The combination of the molar ratio of N-phenyl-o-phenylenediamine:benzaldehyde (1:1) using microwave irradiation and only 1% mol of Er(OTf)3 provides an efficient and environmental mild access to a diversity of benzimidazoles under solvent-free conditions. The proposed method allows for the obtainment of the desired products in a short time and with very high selectivity. 相似文献
992.
The color stability of anthocyanins (ACN) has been shown to be improved by interaction with whey proteins (WP). In this study, we explore the ACN–WP interaction using Fourier transform infrared spectroscopy (IR). ACN from purple corn, grape, and black carrot (50 μM) were evaluated. IR spectra (4000–700 cm−1) were collected for native and preheated (40–80 °C) WP (5 mg/mL) and ACN–WP mixtures at pH 7.4. Soft independent modeling of class analogy was used to analyze the IR data. The WP secondary structure changed after heat treatments and after interaction with ACN. As expected, the WP α-helices decreased, and β-sheet increased after heat treatment. The intensities of the WP amide I and II bands decreased after ACN addition, revealing a decrease in the WP α-helix content. Higher preheating temperatures (70–80 °C) resulted in a more disordered WP structure that favored stronger WP–ACN interactions related to amide III changes. Addition of ACN stabilized WP structure due to heat denaturation, but different ACN structures had different binding affinities with WP. WP structure had less change after interaction with ACN with simpler structures. These results increase our understanding of ACN–WP interactions, providing a potential strategy to extend anthocyanin color stability by WP addition. 相似文献
993.
Paraguay-Delgado Francisco Mendoza Duarte Monica E. Kalu O. Estrada Moreno Ivan A. Alonso-Lemus Ivonne Lardizábal-G Daniel 《Journal of Thermal Analysis and Calorimetry》2020,140(2):735-741
Journal of Thermal Analysis and Calorimetry - Molybdenum trioxide (MoO3) has been studied by four thermal analysis techniques. The as-synthesized material has hexagonal structure (h-MoO3). The... 相似文献
994.
Dr. Markus Joksch Dr. Hemlata Agarwala Dr. Monica Ferro Dr. Dirk Michalik Dr. Anke Spannenberg Priv.-Doz. Dr. Torsten Beweries 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3571-3577
The thermodynamics of halogen bonding of a series of isostructural Group 10 metal pincer fluoride complexes of the type [(3,5-R2-tBuPOCOPtBu)MF] (3,5-R2-tBuPOCOPtBu=κ3-C6HR2-2,6-(OPtBu2)2 with R=H, tBu, COOMe; M=Ni, Pd, Pt) and iodopentafluorobenzene was investigated. Based on NMR experiments at different temperatures, all complexes 1-tBu (R=tBu, M=Ni), 2-H (R=H, M=Pd), 2-tBu (R=tBu, M=Pd), 2-COOMe (R=COOMe, M=Pd) and 3-tBu (R=tBu, M=Pt) form strong halogen bonds with Pd complexes showing significantly stronger binding to iodopentafluorobenzene. Structural and computational analysis of a model adduct of complex 2-tBu with 1,4-diiodotetrafluorobenzene as well as of structures of iodopentafluorobenzene in toluene solution shows that formation of a type I contact occurs. 相似文献
995.
Rmi Platel Ludovic Chaveriat Sarah Le Guenic Rutger Pipeleers Maryline Magnin-Robert Batrice Randoux Pauline Trapet Vincent Lequart Nicolas Joly Patrice Halama Patrick Martin Monica Hfte Philippe Reignault Ali Siah 《Molecules (Basel, Switzerland)》2021,26(1)
The hemibiotrophic fungus Zymoseptoria tritici, responsible for Septoria tritici blotch, is currently the most devastating foliar disease on wheat crops worldwide. Here, we explored, for the first time, the ability of rhamnolipids (RLs) to control this pathogen, using a total of 19 RLs, including a natural RL mixture produced by Pseudomonas aeruginosa and 18 bioinspired RLs synthesized using green chemistry, as well as two related compounds (lauric acid and dodecanol). These compounds were assessed for in vitro antifungal effect, in planta defence elicitation (peroxidase and catalase enzyme activities), and protection efficacy on the wheat-Z. tritici pathosystem. Interestingly, a structure-activity relationship analysis revealed that synthetic RLs with a 12 carbon fatty acid tail were the most effective for all examined biological activities. This highlights the importance of the C12 chain in the bioactivity of RLs, likely by acting on the plasma membranes of both wheat and Z. tritici cells. The efficacy of the most active compound Rh-Est-C12 was 20-fold lower in planta than in vitro; an optimization of the formulation is thus required to increase its effectiveness. No Z. tritici strain-dependent activity was scored for Rh-Est-C12 that exhibited similar antifungal activity levels towards strains differing in their resistance patterns to demethylation inhibitor fungicides, including multi-drug resistance strains. This study reports new insights into the use of bio-inspired RLs to control Z. tritici. 相似文献
996.
Prof. Luciano De Sio Prof. Bin Ding Dr. Monica Focsan Prof. Karin Kogermann Prof. Paula Pascoal-Faria Dr. Francesca Petronela Prof. Geoffrey Mitchell Prof. Eyal Zussman Prof. Filippo Pierini 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(20):6112-6130
The Coronavirus disease 2019 (COVID-19) emergency has demonstrated that the utilization of face masks plays a critical role in limiting the outbreak. Healthcare professionals utilize masks all day long without replacing them very frequently, thus representing a source of cross-infection for patients and themselves. Nanotechnology is a powerful tool with the capability to produce nanomaterials with unique physicochemical and antipathogen properties. Here, how to realize non-disposable and highly comfortable respirators with light-triggered self-disinfection ability by bridging bioactive nanofiber properties and stimuli-responsive nanomaterials is outlined. The visionary road highlighted in this Concept is based on the possibility of developing a new generation of masks based on multifunctional membranes where the presence of nanoclusters and plasmonic nanoparticles arranged in a hierarchical structure enables the realization of a chemically driven and on-demand antipathogen activities. Multilayer electrospun membranes have the ability to dissipate humidity present within the mask, enhancing the wearability and usability. The photothermal disinfected membrane is the core of these 3D printed and reusable masks with moisture pump capability. Personalized face masks with smart nano-assisted destruction of pathogens will bring enormous advantages to the entire global community, especially for front-line personnel, and will open up great opportunities for innovative medical applications. 相似文献
997.
Bruno Pribanic Monica Trincado Frederik Eiler Matthias Vogt Aleix Comas-Vives Hansjörg Grützmacher 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(36):15733-15739
The dehydrogenation of organosilanes (RxSiH4−x) under the formation of Si−Si bonds is an intensively investigated process leading to oligo- or polysilanes. The reverse reaction is little studied. To date, the hydrogenolysis of Si−Si bonds requires very harsh conditions and is very unselective, leading to multiple side products. Herein, we describe a new catalytic hydrogenation of oligo- and polysilanes that is highly selective and proceeds under mild conditions. New low-valent nickel hydride complexes are used as catalysts and secondary silanes, RR′SiH2, are obtained as products in high purity. 相似文献
998.
Dr. Daniele Ragno Dr. Graziano Di Carmine Arianna Brandolese Prof. Olga Bortolini Dr. Pier Paolo Giovannini Prof. Giancarlo Fantin Dr. Monica Bertoldo Prof. Alessandro Massi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(64):14701-14710
The application of N-heterocyclic carbene (NHC) catalysis to the polycondensation of diols and dialdehydes under oxidative conditions is herein presented for the synthesis of polyesters using fossil-based (ethylene glycol, phthalaldehydes) and bio-based (furan derivatives, glycerol, isosorbide) monomers. The catalytic dimethyl triazolium/1,8-diazabicyclo[5.4.0]undec-7-ene couple and stoichiometric quinone oxidant afforded polyester oligomers with a number-average molecular weight (Mn) in the range of 1.5–7.8 kg mol−1 as determined by NMR analysis. The synthesis of a higher molecular weight polyester (polyethylene terephthalate, PET) by an NHC-promoted two-step procedure via oligoester intermediates is also illustrated together with the catalyst-controlled preparation of cross-linked or linear polyesters derived from the trifunctional glycerol. The thermal properties (TGA and DSC analyses) of the synthesized oligoesters are also reported. 相似文献
999.
Matteo Panza Dr. Monica Civera Dr. Jagodige P. Yasomanee Prof. Laura Belvisi Prof. Alexei V. Demchenko 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(51):11831-11836
Presented herein is a study of the conformation and reactivity of highly reactive thioglycoside donors. The structural studies have been conducted using NMR spectroscopy and computational methods. The reactivity of these donors has been investigated in bromine-promoted glycosylations of aliphatic and sugar alcohols. Swift reaction times, high yields, and respectable 1,2-cis stereoselectivity were observed in a majority of these glycosylations. 相似文献
1000.
Ilesha Avasthi Gaganjot Prof. Dr. Monica Katiyar Prof. Dr. Sandeep Verma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(70):16706-16711
Bioinspired materials have become increasingly competitive for electronic applications in recent years owing to the environment-friendly alternatives they offer. The notion of biocompatible solid organic electrolytes addresses the issues concerning potential leakage of corrosive liquids, volatility and flammability of electrolyte solvents. This study presents a new intrinsically coordinated LiI adenine complex that exhibits electrical conductivity as a solid electrolyte capable of self-sustained supply of LiI ions. It exhibits conductivity through moisture-assisted LiI ion motion up to 373 K, and possibly by an ion-hopping mechanism beyond 373 K. This purine-derived solid electrolyte shows enhanced conductivity and transference number demonstrating the potential of purine-based ligands and their coordination complexes in interesting materials applications. 相似文献