1499-53-2Relevant articles and documents
Highly efficient and recyclable copper based ionic liquid catalysts for amide synthesis
Rani, Poonam,Srivastava, Rajendra
, p. 7162 - 7170 (2016)
A series of Cu based ionic liquids was synthesized by the reaction of 1-butyl-3-methylimidazolium salts and copper(ii) salts. These ionic liquids were investigated as catalysts in the synthesis of amides (primary, secondary and tertiary amides). For easy separation and recycling, the Cu based ionic liquids were decorated on nanocrystalline silicalite. The materials were characterized using powder X-ray diffraction, nitrogen adsorption, scanning and transmission electron microscopy, thermogravimetric analysis, and nuclear magnetic resonance, Fourier transform infrared and UV-visible spectroscopy. The Cu based ionic liquids decorated on nanocrystalline silicalite were found to be efficient and recyclable catalysts for the amide synthesis. The catalysts were found to be stable and show negligible loss of the activity even after five cycles.
Benzyne-Mediated Esterification Reaction
Li, Yang,Shi, Jiarong,Zhao, Jinlong
supporting information, p. 7274 - 7278 (2021/10/01)
A benzyne-mediated esterification of carboxylic acids and alcohols under mild conditions has been realized, which is made possible via a selective nucleophilic addition of carboxylic acid to benzyne in the presence of alcohol. After a subsequent transesterification with alcohol, the corresponding esters can be produced efficiently. This benzyne-mediated protocol can be used on the modification of Ibuprofen, cholesterol, estradiol, and synthesis of nandrolone phenylpropionate. In addition, benzyne can also be used to promote lactonization and amidation reaction.
Synthesis of Benzoisoselenazolones via Rh(III)-Catalyzed Direct Annulative Selenation by Using Elemental Selenium
Xu-Xu, Qing-Feng,Nishii, Yuji,Uetake, Yuta,Sakurai, Hidehiro,Miura, Masahiro
supporting information, p. 17952 - 17959 (2021/11/16)
Isoselenazolone derivatives have attracted significant research interest because of their potent therapeutic activities and indispensable applications in organic synthesis. Efficient construction of functionalized isoselenazolone scaffolds is still challenging, and thus new synthetic approaches with improved operational simplicity have been of particular interest. In this manuscript, we introduce a rhodium-catalyzed direct selenium annulation by using stable and tractable elemental selenium. A series of benzamides as well as acrylamides were successfully coupled with selenium under mild reaction conditions, and the obtained isoselenazolones could be pivotal synthetic precursors for several organoselenium compounds. Based on the designed control experiments and X-ray absorption spectroscopy measurements, we propose an unprecedented selenation mechanism involving a highly electrophilic Se(IV) species as the reactive selenium donor. The reaction mechanism was further verified by a computational study.
Preparation of α-amino acids: via Ni-catalyzed reductive vinylation and arylation of α-pivaloyloxy glycine
Chen, Yanchi,Gong, Hegui,Guo, Jiandong,Tao, Xianghua,Wang, Xiaotai
, p. 220 - 226 (2021/01/14)
This work emphasizes easy access to α-vinyl and aryl amino acids via Ni-catalyzed cross-electrophile coupling of bench-stable N-carbonyl-protected α-pivaloyloxy glycine with vinyl/aryl halides and triflates. The protocol permits the synthesis of α-amino acids bearing hindered branched vinyl groups, which remains a challenge using the current methods. On the basis of experimental and DFT studies, simultaneous addition of glycine α-carbon (Gly) radicals to Ni(0) and Ar-Ni(ii) may occur, with the former being more favored where oxidative addition of a C(sp2) electrophile to the resultant Gly-Ni(i) intermediate gives a key Gly-Ni(iii)-Ar intermediate. The auxiliary chelation of the N-carbonyl oxygen to the Ni center appears to be crucial to stabilize the Gly-Ni(i) intermediate.
Discovery of N-(2-(Benzylamino)-2-oxoethyl)benzamide analogs as a novel scaffold of pancreatic β-cell protective agents against endoplasmic reticulum stress
Eeda, Venkateswararao,Herlea-Pana, Oana,Lim, Hui-Ying,Wang, Weidong
, p. 388 - 393 (2020/01/02)
Endoplasmic reticulum (ER) stress-induced pancreatic β-cell dysfunction and death play important roles in the development of diabetes. The 1,2,3-triazole derivative 1 is one of only a few structures that have thus far been identified that protect β cells against ER stress. However, this compound has narrow activity range and limited aqueous solubility. To overcome these, we designed and synthesized a new scaffold in which the triazole pharmacophore was substituted with a glycine-like amino acid. Structure–activity relationship studies on this scaffold identified a N-(2-(Benzylamino)-2-oxoethyl)benzamide analog WO5m that possesses β-cell protective activity against ER stress with much improved potency (maximal activity at 100% with EC50 at 0.1?±?0.01?μm) and water solubility. Identification of this novel β-cell protective scaffold thus provides a new promising modality for the treatment of diabetes.
3,6-Di(pyridin-2-yl)-1,2,4,5-tetrazine (pytz) catalysed metal-free amide bond formation from thioacids and amines at room temperature
Samanta, Suvendu,Ray, Shounak,Bhaduri, Samanka Narayan,Samanta, Partha Kumar,Biswas, Papu
supporting information, (2020/08/10)
A 3,6-di(pyridin-2-yl)-1,2,4,5-tetrazine (pytz) catalysed efficient, mild and metal-free method has been developed for direct amide bond synthesis from simple thioacids and amines as starting materials. This methodology is useful for aromatic, aliphatic, and heteroaromatic thioacids as well as primary, secondary, heterocyclic, and even functionalized amines. A wide substrates scope, operationally mild conditions, and acylation of amines without affecting other functional groups such as alcohols, esters, carbodithioates, among others make this strategy very attractive and practical.
Synthesis of some hippuric acid substrate linked novel pyrazoles as antimicrobial agents
Verma, Anil,Kumar, Vinod,Khare, Rajshree,Singh, Joginder
, p. 522 - 526 (2019/02/06)
Escalating resistance of microorganisms to the currently accessible antimicrobial drugs has forced to synthesize some novel biologically active compounds as efficient alternates via economical substrates. Hence, hippuric acid was used as one of the starting materials to synthesize pyrazole derivatives. All the synthesized compounds were characterized by IR, NMR (1H & 13C) and mass spectral data. The antimicrobial potential of synthesized compounds has been explored against four bacterial and two fungal strains. Among the 12 compounds, 3 compounds 8j, 8k and 8l were found to exhibit prominent antimicrobial potential as compared with the standards ciprofloxacin and amphotericin-B.
Microwave-Assisted Ruthenium-Catalysed ortho-C?H Functionalization of N-Benzoyl α-Amino Ester Derivatives
Sharma, Nandini,Bahadur, Vijay,Sharma, Upendra K.,Saha, Debasmita,Li, Zhenghua,Kumar, Yogesh,Colaers, Jona,Singh, Brajendra K,Van der Eycken, Erik V.
supporting information, p. 3083 - 3089 (2018/08/24)
A microwave-assisted highly efficient intermolecular C?H functionalization sequence has been developed to access substituted isoquinolones using α-amino acid esters as a directing group. This methodology enables a wide range of N-benzoyl α-amino ester derivatives to react via a Ru-catalysed C?H bond activation sequence, to form isoquinolones with moderate to excellent yields. As an additional advantage, our strategy proved to be widely applicable and also enabled the reaction of alkenes to provide access to alkenylated benzamides. The methodology was also extended towards the synthesis of isoquinoline alkaloids derivatives viz. oxyavicine and a dipeptide. The developed protocol is simple and cheap, avoids tedious workup procedures and works efficiently under MW irradiation. (Figure presented.).
Synthesis and preliminary anti-inflammatory and anti-bacterial evaluation of some diflunisal aza-analogs
Carta, Davide,Brun, Paola,Dal Pra, Matteo,Bernabè, Giulia,Castagliuolo, Ignazio,Ferlin, Maria Grazia
, p. 1017 - 1032 (2018/06/27)
Our aim was to identify new multi-target compounds endowed with both anti-inflammatory and anti-bacterial activities for treatment of human infections. Diflunisal, a nonsteroidal anti-inflammatory agent, has recently been repurposed for its anti-virulence properties against methicillin-resistant Staphylococcus aureus. Effective synthesis of some aza-analogs of the anti-inflammatory drug diflunisal was carried out following the route involving key oxazole intermediates to obtain o- and m-hydroxypyridinecarboxylic acid derivatives. The newly synthesized diflunisal aza-analogs did not exhibit cytotoxic activity up to 80 μM and some of them exhibited anti-inflammatory activities, decreasing the levels of pro-inflammatory cytokines and prostaglandins induced by bacterial lipopolysaccharide in human primary macrophages. Ten of the diflunisal aza-analogs were found to have interesting antibacterial activity, sensitizing S. aureus, Streptococcus pyogenes, Enterococcus faecium, and Pseudomonas aeruginosa to the antibacterial effects of beta-lactam antibiotics and protein synthesis inhibitors.
Synthesis and antimicrobial activities of novel sorbic and benzoic acid amide derivatives
Wei, Qingyi,Wang, Xiaomei,Cheng, Jun-Hu,Zeng, Guangxiang,Sun, Da-Wen
, p. 220 - 232 (2018/06/26)
A series of sorbic and benzoic acid amide derivatives were synthesized by conjugating sorbic acid (SAAD, a1–a7) or benzoic acid (BAAD b1–b6) with amino acid esters and their antimicrobial activities were investigated against Escherichia coli, Bacillus subtilis and Staphylococcus aureus, mixed bacteria from rancid milk, Saccharomyces cerevisiae, and Aspergillus niger. The antimicrobial activity of sorbic acid amides was better than that of benzoic acid amides. The minimum inhibitory concentrations (MIC) of compound isopropyl N-[1-oxo-2, 4-hexadien-1-yl]-L-phenylalaninate (a7) were 0.17 mM against B. subtilis, and 0.50 mM against S. aureus, while the MIC values of sorbic acid were more than 2 mM respectively. Also, compound a7 displayed pH-independent antimicrobial activity in the range of pH 5.0–9.0 and was effective at pH 9.0. These results demonstrated that the conjugation of sorbic acid with amino acid esters led to significant improvement of in vitro antimicrobial attributes, but little effect was observed for benzoic acid amide derivatives.
