4888-33-9Relevant articles and documents
Visible-Light Induced C(sp2)?H Amidation with an Aryl–Alkyl σ-Bond Relocation via Redox-Neutral Radical–Polar Crossover
Chang, Sukbok,Jeong, Jiwoo,Jung, Hoimin,Keum, Hyeyun,Kim, Dongwook
supporting information, p. 25235 - 25240 (2021/10/25)
We report an approach for the intramolecular C(sp2)?H amidation of N-acyloxyamides under photoredox conditions to produce δ-benzolactams with an aryl-alkyl σ-bond relocation. Computational studies on the designed reductive single electron transfer strategy led us to identify N-[3,5-bis(trifluoromethyl)benzoyl] group as the most effective amidyl radical precursor. Upon the formation of an azaspirocyclic radical intermediate by the selective ipso-addition with outcompeting an ortho-attack, radical–polar crossover was then rationalized to lead to the rearomative ring-expansion with preferential C?C bond migration.
Schmidt reaction on substituted 1-indanones / N-alkylation: Synthesis of benzofused six-membered ring lactams and their evaluation as antimicrobial agents
Arora, Rashi,Bala, Renu,Kumari, Poonam,Sood, Sumit,Yadav, Ajar Nath,Singh, Nasib,Singh, Karan
, p. 606 - 613 (2019/05/01)
Background: The presence of bicyclic lactams is reflected in various pharmaceuticals, natural products, agrochemicals and active components of various dyes. Nowadays, to see the increasing rate of antimicrobial resistance and high incidence of microbial infections, there is a strong need to develop novel antimicrobial agents. In this study, we synthesized some benzofused six membered ring lactams and their alkyl derivatives as a trial to obtain valuable precursors for the discovery of future an-timicrobial drugs. Methods: The substituted lactams 3,4-dihydro-2(1H)-quinolinones 3a-c and 3,4-dihydro-1(2H)-isoquinolinones 4a-c were synthesized by Schmidt reaction on indanones 2a-c which were obtained by Friedel-Crafts reaction on β-substituted α,β-unsaturated carboxylic acids 1a-c. Lactams 6 and 7 were obtained by N-alkylation on benzofused lactams 3a-c and 4a-c in good to excellent yields. Structures of all products were well characterized by the rigorous analysis of their IR,1H NMR,13C NMR, MS and elemental analysis. The in vitro antimicrobial activities of all the synthesized compounds 6 and 7 were determined against Gram-positive, Gram-negative bacteria and the fungal species Candida albi-cans using broth macrodilution method. Results: The Schmidt reaction of 3-methylindanone, 3-phenylindanone and 3,3-dimethylindanone using methane sulphonic acid was found to behave differently with respect to isolated yield as well as isomeric ratio of both lactams. Bacterial growth inhibition was observed with bicyclic lactam derivatives although their MIC values were higher than ampicillin. The significant inhibitory effects were shown by majority of compounds with MIC values 125-250 μg/ml. Antifungal activity of bicyclic lactam derivatives was observed against C. albicans. However, MICs values of all tested compounds were higher compared to standard antifungal agent miconazole. Conclusion: The four Schmidt experimental conditions were tried with the aim of achieving both 6-membered ring lactams in equal ratio and NaN3/MeSO3H was identified to fulfill our purpose. As evident by structure-activity relationship, the tested compounds have not resulted in superior antibacterial or anti-fungal compounds compared to standard antimicrobials. Hence, there is still a need to carry out further modifications in bicyclic lactams structure in order to more efficacious antimicrobial lead molecules.
Novel nano-titania embedded on graphite (nano-TiO2@Cg) as an efficient, eco-friendly, and recyclable catalyst for one-pot, solvent-free synthesis of 4-aryl-3,4-dihydroquinolin-2(1H)-ones, 3-methyl-4-aryl/alkyl-2,4,5,7-tetrahydropyrazolo[3,4-b]pyridin-6-ones, and coumarin-3-carboxylic esters
Nikoofar, Kobra,Molaei Yielzoleh, Fatemeh
, p. 7353 - 7367 (2018/08/29)
Abstract: A novel acid catalyst has been synthesized by commercial anatase phase nano-TiO2 and graphite (nano-TiO2@Cg) via a simple procedure and characterized by Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, thermogravimetric analysis, field emission scanning electron microscopy, and potentiometric titration techniques. It has been utilized as a convenient nano-catalyst to accelerate the one-pot, solvent-free, three-component reaction of Meldrum’s acid, aromatic amines (5-methylpyrazol-3-amine), and various aromatic aldehydes to form 4-aryl-3,4-dihydroquinolin-2-(1H)-ones and 3-methyl-4-aryl/alkyl-2,4,5,7-tetrahydropyrazolo[3,4-b]pyridin-6-ones, respectively. The catalytic activity has also examined for the preparation of coumarin-3-carboxylic esters from Meldrum’s acid, salicylaldehydes, and alcohols successfully. Low catalyst loading, clean process without utilizing any hazardous solvent, easy workup procedure, reusability and recyclability of the nano-catalyst within four runs without activity loss, high yields of the products, in addition with utilizing a vast range of substrates are some highlighted points of the reported protocols. Graphical abstract: [Figure not available: see fulltext.]
