659-30-3Relevant articles and documents
Enzyme-Inspired Lysine-Modified Carbon Quantum Dots Performing Carbonylation Using Urea and a Cascade Reaction for Synthesizing 2-Benzoxazolinone
Hasani, Morteza,Kalhor, Hamid R.
, p. 10778 - 10788 (2021/09/08)
Catalysts as the dynamo of chemical reactions along with solvents play paramount roles in organic transformations in long-lasting modes. Thus, developing effective and biobased catalysts in nontoxic solvents is highly in demand. In this report, carbon quantum dots (CQDs) functionalized with-lysine (Lys-CQDs) were generated from entirely nature-derived materials; they were demonstrated to be a promising catalyst for C-N bond formation in choline chloride urea (ChCl/U), a natural deep eutectic solvent (NADES). Among a number of synthesized CQDs, Lys-CQD turned out to be a powerful catalyst in the model reaction with aniline to afford phenyl urea. This type of transformation is important because aniline as a nucleophile has low activity, and urea is a very weak electrophile but an abundant natural source of the carbonyl moiety at the same time. The optimized reaction was performed under a highly desirable condition without using tedious and toxic workup processes at a low temperature (37 °C for aliphatic amines and 60 °C for aniline derivatives), as well as by embracing the broad scope of products in good to high yields even with weak nucleophiles such as aniline. A proposed acid-activated mechanism was suggested for the model reaction that was further confirmed by detecting ammonia as the leaving group. To show further multifunctionality of the catalyst, a cascade catalysis approach was developed for synthesizing 2-benzoxazolinone, which was furnished in a two-step transformation, starting from 2-aminophenol. Using X-ray crystallography, the structure of the final product in the cascade reaction was also determined. The catalyst was characterized using various analytical techniques including SEM, TEM, AFM, XRD, IR spectroscopy, UV-vis spectroscopy, DLS, and fluorescence spectroscopy. Measuring the acid/base sites by back titration, the catalyst was shown to be highly functionalized by the lysine functional group. The size of the catalyst was determined to be in the range of 1-8 nm, having a well-dispersed surface. In all, Lys-modified CQD, as a metal-free catalyst, was synthesized, characterized, and optimized for carbonylation, as well as a cascade reaction, under mild conditions. The whole process including catalyst synthesis and organic transformations is economically competitive and fulfills all requirements toward viability.
Dual palladium-photoredox catalyzed chemoselective C-H arylation of phenylureas
Babu, Sakamuri Sarath,Shahid,Gopinath, Purushothaman
supporting information, p. 5985 - 5988 (2020/06/04)
A highly chemoselective C-H arylation of phenylureas has been accomplished using dual palladium-photoredox catalysis at room temperature without any additives, base or external oxidants. Regioselective C-H arylation ofN,N'-diaryl substituted unsymmetrical phenylureas has also been accomplished by a careful choice of aryl groups.
Design and synthesis of novel N-(4-(Pyridin-2-yloxy)benzylidene)-4-[4-(substituted)phenyl]semicarbazides as potential anticonvulsant agents
Singh, Prem,Tripathi, Laxmi
, p. 2193 - 2200 (2018/09/10)
A new series of N-(4-(pyridin-2-yloxy)benzylidene)-4-[4-(substituted)phenyl]semicarbazides (PSSD1-8) were designed and synthesized keeping in view the structural requirement of pharmacophore and evaluated for their possible anticonvulsant activity. All the derivatives were synthesized by the given scheme and reaction process was monitored by thin layer chromatography. The structure of synthesized derivatives was confirmed by FT-IR, 1H NMR, mass spectroscopy and elemental analysis. The anticonvulsant activity was established after intraperitoneal administration in MES and scMET seizure models. The most active compound of the series was 1-(4-(pyridin-2-yloxy)-benzylidene)-4-p-tolylsemicarbazide (PSSD5). A molecular docking study was carried out in order to assess the interaction and binding modes with target receptor/enzyme. Titled compounds were found to strongly bind to human gamma-aminobutyric acid receptor (GABAAR-β3). A computational study was also carried to predict the pharmacokinetic properties of the synthesized compounds.
