616235-94-0Relevant academic research and scientific papers
Aiding the versatility of simple ammonium ionic liquids by the synthesis of bioactive 1,2,3,4-tetrahydropyrimidine, 2-aminothiazole and quinazolinone derivatives
Kakati, Praachi,Singh, Preeti,Yadav, Priyanka,Awasthi, Satish Kumar
, p. 6724 - 6738 (2021/04/22)
Simple ammonium ionic liquids [ILs] are efficient, green, environmentally friendly catalysts in promoting the Biginelli condensation reaction, Hantzsch reaction and Niementowski reaction to afford 1,2,3,4-tetrahydropyrimidine, 2-aminothiazole and quinazolinone derivatives respectively by eliminating the need for harmful volatile organic solvents. These [ILs] are air and water stable, easy to prepare and cost-effective. The effects of the anions and cations present in [IL] on reactions were investigated. The results clearly indicated that the Biginelli condensation reaction, Hantzsch reaction and Niementowski reaction were heavily influenced by the acidity of [IL], and among various ammonium ionic liquids, [Et3NH][HSO4] showed the best catalytic activity. Furthermore, [IL] could be easily separated and reused with a slight loss of its activity. This technique provided a good alternative way for the industrial synthesis of 1,2,3,4-tetrahydropyrimidinones, 2-aminothiazoles and quinazolinones. The present processes are eco-friendly methods for the synthesis of these derivatives authenticated by several green parameters, namely,E-factor, process mass intensity, reaction mass efficiency, atom economy, and carbon efficiency.
Metal-free C-H methylation and acetylation of heteroarenes with PEG-400
Kudale, Vishal Suresh,Wang, Jeh-Jeng
supporting information, p. 3506 - 3511 (2020/06/25)
The generation of a methyl carbon source from renewable and cheap sources is challenging. Herein, we describe a novel and an efficient route for methylation and acetylation of aza-heteroarenes using PEG-400 under O2and TsOH·H2O for the first time by tuning the reaction conditions using a different set of starting materials. The key features of the current protocol are oxidative C-O and C-C bond scission under metal-free conditions with good functional group tolerance, and a broad substrate scope. The potential applicability of the designed methodology was demonstrated for the synthesis of central nervous system (CNS) depressant and anticonvulsant drug molecules by a one-pot strategy.
Sustainable methine sources for the synthesis of heterocycles under metal- and peroxide-free conditions
Senadi, Gopal Chandru,Kudale, Vishal Suresh,Wang, Jeh-Jeng
, p. 979 - 985 (2019/03/12)
Alcohols and ethers were identified as sustainable methine sources for synthesizing quinazolinone and benzimidazole derivatives using a combination of TsOH·H2O/O2 and appropriate bis-nucleophiles for the first time. Deuterium labeling studies clearly proved that the C2 hydrogen of the synthesized heterocycles came from the methine source. These unique reaction conditions were successfully applied to the synthesis of echinozolinone (2e′), 2f′ (a common precursor of rutaecarpine and (±) evodiamine), and dimedazole (6d). Notable features of this method include its low toxicity, use of commercial feedstocks as substrates, low cost, broad functional group tolerance and suitability for a wide range of bis-nucleophilic starting materials.
Enantioselective Synthesis of 3-Arylquinazolin-4(3H)-ones via Peptide-Catalyzed Atroposelective Bromination
Diener, Matthew E.,Metrano, Anthony J.,Kusano, Shuhei,Miller, Scott J.
supporting information, p. 12369 - 12377 (2015/10/12)
We report the development of a tertiary amine-containing β-turn peptide that catalyzes the atroposelective bromination of pharmaceutically relevant 3-arylquinazolin-4(3H)-ones (quinazolinones) with high levels of enantioinduction over a broad substrate scope. The structure of the free catalyst and the peptide-substrate complex were explored using X-ray crystallography and 2D-NOESY experiments. Quinazolinone rotational barriers about the chiral anilide axis were also studied using density functional theory calculations and are discussed in light of the high enantioselectivities observed. Mechanistic studies also suggest that the initial bromination event is stereodetermining, and the major monobromide intermediate is an atropisomerically stable, mono-ortho-substituted isomer. The observation of stereoisomerically stable monobromides stimulated the conversion of the tribromide products to other atropisomerically defined products of interest. For example, (1) a dehalogenation Suzuki-Miyaura cross-coupling sequence delivers ortho-arylated derivatives, and (2) a regioselective Buchwald-Hartwig amination procedure installs para-amine functionality. Stereochemical information was retained during these subsequent transformations.
Copper-catalyzed radical methylation/C-H amination/oxidation cascade for the synthesis of quinazolinones
Bao, Yajie,Yan, Yizhe,Xu, Kun,Su, Jihu,Zha, Zhenggen,Wang, Zhiyong
, p. 4736 - 4742 (2015/05/13)
A copper-catalyzed radical methylation/sp3 C-H amination/oxidation reaction for the facile synthesis of quinazolinone was developed. In this cascade reaction, dicumyl peroxide acts not only as a useful oxidant but also as an efficient methyl source. Notably, a methyl radical, generated from peroxide, was confirmed by electron paramagnetic resonance for the first time.
A microwave-assisted and heteropolyacids-catalysed cyclocondensation reaction for the synthesis of 4(3H)-quinazolinones
Ighilahriz, Karima,Boutemeur, Baya,Chami, Fariza,Rabia, Cherifa,Hamdi, Maamar,Hamdi, Safouane M.
, p. 779 - 789 (2008/09/18)
We have investigated a microwave-assisted synthesis of 4(3H)-quinazolinones by condensation of anthranilic acid, orthoesters (or formic acid) and substituted anilines, using Keggin-type heteropolyacids (H3PW 12O40·13H
Synthesis of 3,4-dihydropyrimidine-2(1H)-thiones and quinazolin-4(3H)-ones over Yb(III)-resin catalyst under solvent-free conditions
Jiang, Zhidong,Chen, Ruifang
, p. 503 - 509 (2007/10/03)
Ytterbium(III) reagent supported on ion exchange resin is applied to the multicomponent condensation reactions under solvent-free conditions. One-pot synthesis of a library of 3,4-dihydropyrimidine-2(1H)-thiones and quinazolin-4(3H)-ones were described. The advantages of easy separation and recyclability of the catalysts were demonstrated.
Synthesis and in vitro study of platelet antiaggregant activity of 1,2,3,4-tetrahydroquinazoline derivatives
Gravier,Dupin,Casadebaig,Hou,Boisseau,Bernard
, p. 531 - 535 (2007/10/02)
Some original 3-substituted 1,2,3,4-tetrahydroquinazolines were synthesized. Their antiplatelet activity was evaluated in vitro with respect to aggregation induced by the main inducers (ADP, collagen, arachidonic acid), platelet serotonin release reaction and thromboxane A2 synthesis. All these molecules possess an inhibiting power which, compared to that of aspirin in the same conditions, is the same or greater when aggregation is induced by ADP.
