4771-08-8Relevant academic research and scientific papers
Synthesis of polyaramids in γ-valerolactone-based organic electrolyte solutions
Winters, Jonas,Bolia, Raheed,Dehaen, Wim,Binnemans, Koen
supporting information, p. 1228 - 1239 (2021/02/26)
The current synthetic procedures for polyaramids mainly involve the use of amide solvents such asN-methylpyrrolidone andN,N-dimethylacetamide. However, these solvents are suspected to be teratogenic and are considered ‘Substances of Very High Concern’ by the European Commission. Here we propose a benign alternative solvent system: an Organic Electrolyte Solution (OES) consisting of γ-valerolactone (GVL) and a small amount of the ionic liquid 1-methyl-3-octylimidazolium chloride, [C8MIm][Cl]. Three commercially relevant polyaramids were synthesized: poly-p-phenylene terephthalamide (PPTA), poly-m-phenylene isophthalamide (PMIA) and copoly(p-phenylene/3,4′-diphenylether terephthalamide) (ODA/PPTA). PMIA was successfully synthesized in the OES containing [C8MIm][Cl] in a molar fraction ofxIL= 0.043, achieving an inherent viscosity ofηinh= 1.94 ± 0.064 dL g?1, which is on par with the current industrial standard and the benchmark lab scale synthesis. The reaction mixture could also be directly used for the wet spinning of polyaramid fibers, and all components of the solvent could be recycled in good yields by a series of evaporation and distillation steps. ODA/PPTA could be synthesized, but only rather low inherent viscosities were achieved. The reaction mixture was too viscoelastic to be spun by our small-scale spinning setup. PPTA always instantly precipitated and could not be synthesized from a [C8MIm][Cl]/GVL OES. α-Picoline, the organic base which was added to capture the released HCl during the reaction, was found to play a pivotal role in the polymerization reaction. By undergoing an acid-base reaction with HCl, it forms a protic ionic liquidin situwhich increases the solubility of the polymer.
Carboxylic Acid Deoxyfluorination and One-Pot Amide Bond Formation Using Pentafluoropyridine (PFP)
Brittain, William D. G.,Cobb, Steven L.
supporting information, p. 5793 - 5798 (2021/08/01)
This work describes the application of pentafluoropyridine (PFP), a cheap commercially available reagent, in the deoxyfluorination of carboxylic acids to acyl fluorides. The acyl fluorides can be formed from a range of acids under mild conditions. We also demonstrate that PFP can be utilized in a one-pot amide bond formation via in situ generation of acyl fluorides. This one-pot deoxyfluorination amide bond-forming reaction gives ready access to amides in yields of ≤94%.
Iron-catalyzed cross-coupling of N?methoxy amides and arylboronic acids for the synthesis of N-aryl amides
Li, Jinhui,Liu, Jin-Biao,Luo, Nianhua,Qiu, Guanyinsheng,Ren, Shangfeng,Wang, Ying,Xie, Huilin
, (2021/11/11)
An efficient iron-catalyzed synthesis of N-aryl amides from N?methoxy amides and arylboronic acids is developed. FeCl3 is used as the sole catalyst for the cross-coupling reaction between N?methoxy amides and arylboronic acids without any other
Manganese Catalyzed Direct Amidation of Esters with Amines
Fu, Zhengqiang,Wang, Xinghua,Tao, Sheng,Bu, Qingqing,Wei, Donghui,Liu, Ning
, p. 2339 - 2358 (2021/02/03)
The transition metal catalyzed amide bond forming reaction of esters with amines has been developed as an advanced approach for overcoming the shortcomings of traditional methods. The broad scope of substrates in transition metal catalyzed amidations remains a challenge. Here, a manganese(I)-catalyzed method for the direct synthesis of amides from a various number of esters and amines is reported with unprecedented substrate scope using a low catalyst loading. A wide range of aromatic, aliphatic, and heterocyclic esters, even in fatty acid esters, reacted with a diverse range of primary aryl amines, primary alkyl amines, and secondary alkyl amines to form amides. It is noteworthy that this approach provides the first example of the transition metal catalyzed amide bond forming reaction from fatty acid esters and amines. The acid-base mechanism for the manganese(I)-catalyzed direct amidation of esters with amines was elucidated by DFT calculations.
Synthesis of 2-Amino-1,3-dienes from Propargyl Carbonates via Palladium-Catalyzed Carbon-Nitrogen Bond Formation
O'Broin, Calvin Q.,Guiry, Patrick J.
supporting information, p. 879 - 883 (2020/02/04)
A catalytic method to synthesize 1,3,-dienes from propargylic precursors is reported. This palladium-catalyzed carbon-nitrogen bond-forming reaction furnishes 2-amino-1,3-dienes in excellent yields (up to 98%) and shows a broad tolerance to functional group diversity. The reaction has been demonstrated for over 30 amine substrates, including anilines and indoles, and proceeds under mild neutral conditions. The resulting 1,3-dienes are of great synthetic interest because of their further reaction potential.
N-Phenylbenzamide derivatives as alternative oxidase inhibitors: Synthesis, molecular properties, 1H-STD NMR, and QSAR
Barsottini, Mario R. O.,Carazzolle, Marcelo F.,Costa, Paulo C. S.,Evangelista, Joel S.,Miranda, Paulo C. M. L.,Nascimento, Andrey F. Z.,Pereira, Gon?alo A. G.,Pires, Bárbara A.,Rocco, Silvana A.,Sfor?a, Maurício L.,Silva, Jaqueline S.,Vieira, Maria L. L.,Zeri, Ana C. M.
, (2020/02/27)
In the present work, 117 N-phenylbenzamides (NPDs) were prepared and evaluated against recombinant AOX from the fungal pathogen Moniliophthora perniciosa. 1H, 13C NMR, FTIR, and mass spectra provided structural information on NPDs. The library compounds were tested as Alternative Oxidase inhibitors in two different assays using the model yeast Pichia pastoris: cell growth and oxygen consumption assays. The most active compound, 3FH, was further characterized by DRX and 1H-NMR-STD. Single crystal X-ray diffraction showed intra- and intermolecular interactions of 3FH in solid-state and elucidated its 3D structural configuration. 1H-NMR-STD allowed us to derive protein-ligand interactions in a membrane-mimetic system and evidenced an outstanding interaction of 3FH with this enzyme. Results of both biological assays were used as input to Quantitative Structure-Activity Relationship models, which highlighted the more important molecular fragments contributions for protein-ligand interaction.
Synthesis of new phenolic compounds and biological evaluation as antiproliferative agents
Ibrahim, Marwa A,George, Riham F,Abou-Seri, Sahar M,El-Moghazy, Samir M
, p. 181 - 192 (2020/01/06)
New series of phenolic azomethine compounds in addition to 5-arylidene thiazolidinones are synthesized and screened for their anticancer activity against the brain cancer cell line SNB-75 and non-small lung cancer cells HOP-92. The azomethine derivative 12b is the most active compound against SNB-75 displaying an IC50 value of 0.14 μM. Compounds 7b, 16a and 27d display submicromolar activity against the HOP-92 cell line with IC50 values of 0.73, 0.74 and 0.81 μM, respectively. Moreover, studying the cytotoxic effects of the most active compounds against normal lung cells WI-38 revealed that compounds 7b, 16a and 27d showed high safety profiles as anticancer agents.
Copper-Catalyzed Radical N-Demethylation of Amides Using N-Fluorobenzenesulfonimide as an Oxidant
Yi, Xuewen,Yi, Xuewen,Lei, Siyu,Liu, Wangsheng,Che, Fengrui,Yu, Chunzheng,Liu, Xuesong,Wang, Zonghua,Zhou, Xin,Zhang, Yuexia
supporting information, p. 4583 - 4587 (2020/05/05)
An unprecedented N-demethylation of N-methyl amides has been developed by use of N-fluorobenzenesulfonimide as an oxidant with the aid of a copper catalyst. The conversion of amides to carbinolamines involves successive single-electron transfer, hydrogen-atom transfer, and hydrolysis, and is accompanied by formation of N-(phenylsulfonyl)benzenesulfonamide. Carbinolamines spontaneously decompose to N-demethylated amides and formaldehyde, because of their inherent instability.
Decarboxylative/Oxidative Amidation of Aryl α-Ketocarboxylic Acids with Nitroarenes and Nitroso Compounds in Aqueous Medium
Barak, Dinesh S.,Dahatonde, Dipak J.,Dighe, Shashikant U.,Kant, Ruchir,Batra, Sanjay
supporting information, p. 9381 - 9385 (2020/11/30)
The decarboxylative/oxidative amidation of aryl α-ketocarboxylic acids with 5-aryl-3-nitroisoxazole-4-carboxylates and substituted dinitrobenzenes under oxidative aqueous conditions to afford N-aryl amides is described. The reaction is suggested to proceed via a radical pathway in which a benzoyl nitroxyl radical, the key intermediate formed from reaction between nitroarene and benzoyl radical from glyoxalic acid, couples with hydroxyl radical from water to produce amide. Mechanistic insight allowed the scope of the strategy to be expanded to the synthesis of amides via reaction between aryl α-ketocarboxylic acids and nitroso compounds.
Design, synthesis, in-silico studies and biological screening of quinazolinone analogues as potential antibacterial agents against MRSA
Qureshi, Shahnawaz I.,Chaudhari, Hemchandra K.
supporting information, p. 2676 - 2688 (2019/05/17)
Type or The emergence of resistance to antibiotic has developed a complicated situation in the treatment of bacterial infections. Considering the antimicrobial resistance phenomenon as one of the greatest challenge of medicinal chemists for search of better anti-bacterial agents, which have potential narrow spectrum activity with low development of resistance potential and low toxicity to host. Cross-linking of peptidoglycan is a key step catalyze by Penicillin binding protein (PBP) to maintain integrity of cell wall in bacterial cell. However, these Penicillin binding protein (PBP) has developed resistance in methicillin-resistant Staphylococcus aureus (MRSA) due to acquisition of additional PBP2a. Various Quinazolinone analogues are reported in literature as potential anti-bacterial agents against MRSA. In present study new quinazolinone analogues has been designed, guided by molecular docking, In-silico and MM-GBSA study. Newly designed molecules have been synthesized by medicinal chemistry route and their characterization was done by using IR, NMR, & HR-MS techniques. Biological evaluation of synthesized compounds has been done on wild type Gram-negative (Escherichia coli), Gram-positive (Staphylococcus aureus) and resistant MRSA bacterial strains using Streptomycin, Kanamycin and Linezolid as standard drugs respectively. The in vitro evaluation results have shown that compound 5f is active with MIC value 15.625 μg/mL against S. aureus and with MIC value 31.25 μg/mL against MRSA.
