99944-12-4Relevant academic research and scientific papers
Biomimetic alloxan-catalyzed intramolecular redox reaction with O2: One-pot atom-economic synthesis of sulfinyl-functionalized benzimidazoles
Zhang, Shiqi,Yi, Dong,Li, Guangxun,Li, Ling,Zhao, Gang,Tang, Zhuo
supporting information, (2020/12/25)
Given the necessity of sacrificial reductants in various biomimetic aerobic oxygenations, alloxan-catalyzed aerobic redox system for one-pot atom-economic synthesis of sulfinyl-functionalized benzimidazoles was developed by ingeniously binding both the substrate sulfide and sacrificial reductant. This mild and transition-metal-free protocol undergoes two oxidations without additional sacrificial reagents, except for the environmentally benign molecular oxygen.
1,2-Disubstituted Benzimidazoles by the Iron Catalyzed Cross-Dehydrogenative Coupling of Isomeric o-Phenylenediamine Substrates
Foss, Frank W.,Palacios, Philip M.,Pierce, Brad S.,Thapa, Pawan,Tran, Tam
, p. 1991 - 2009 (2020/03/13)
Benzimidazoles are common in nature, medicines, and materials. Numerous strategies for preparing 2-arylbenzimidazoles exist. In this work, 1,2-disubstituted benzimidazoles were prepared from various mono- and disubstituted ortho-phenylenediamines (OPD) by iron-catalyzed oxidative coupling. Specifically, O2 and FeCl3·6H2O catalyzed the cross-dehydrogenative coupling and aromatization of diarylmethyl and dialkyl benzimidazole precursors. N,N′-Disubstituted-OPD substrates were significantly more reactive than their N,N-disubstituted isomers, which appears to be relative to their propensity for complexation and charge transfer with Fe3+. The reaction also converted N-monosubstituted OPD substrates to 2-substituted benzimidazoles; however, electron-poor substrates produce 1,2-disubstituted benzimidazoles by intermolecular imino-transfer. Kinetic, reagent, and spectroscopic (UV-vis and EPR) studies suggest a mechanism involving metal-substrate complexation, charge transfer, and aerobic turnover, involving high-valent Fe(IV) intermediates. Overall, comparative strategies for the relatively sustainable and efficient synthesis of 1,2-disubstituted benzimidazoles are demonstrated.
Indoloquinoxaline derivatives as promising multi-functional anti-Alzheimer agents
Kanhed, Ashish M.,Patel, Dushyant V.,Patel, Kirti V.,Patel, Kishan B.,Patel, Nirav R.,Prajapati, Navnit K.,Sinha, Anshuman,Thakor, Priyanka S.,Yadav, Mange Ram
, (2020/11/02)
To confront a disease like Alzheimer’s disease having complex pathogenesis, development of multitarget-directed ligands has emerged as a promising drug discovery approach. In our endeavor towards the development of multitarget-directed ligands for Alzheimer’s disease, a series of indoloquinoxaline derivatives were designed and synthesized. In vitro cholinesterase inhibition studies revealed that all the synthesized compounds exhibited moderate to good cholinesterase inhibitory activity. 6-(6-(Piperidin-1-yl)hexyl)-6H-indolo[2,3-b]quinoxaline 9f was identified as the most potent and selective BuChE inhibitor (IC50 = 0.96 μM, selectivity index = 0.17) that possessed 2 fold higher BuChE inhibitory activity compared to the commercially approved reference drug donepezil (IC50 = 1.87 μM). Moreover, compound 9f is also endowed with self-induced Aβ1-42 aggregation inhibitory activity (51.24% inhibition at 50 μM concentration). Some of the compounds of the series also displayed moderate anti-oxidant activity. To perceive a putative binding mode of the compound 9f, molecular docking studies were carried out, and the results pointed out significant interactions of compound 9f with the enzymes in the binding sites of cholinesterases as well as Aβ1-42. Additionally, compound 9f exhibited favorable in silico ADMET properties. Put together these findings project compound 9f as a potential multitarget-directed ligand in the direction of developing novel anti-AD drugs. Communicated by Ramaswamy H. Sarma.
Discovery of isoalloxazine derivatives as a new class of potential anti-Alzheimer agents and their synthesis
Kanhed, Ashish M.,Sinha, Anshuman,Machhi, Jatin,Tripathi, Ashutosh,Parikh, Zalak S.,Pillai, Prakash P.,Giridhar, Rajani,Yadav, Mange Ram
, p. 7 - 12 (2015/06/08)
This article describes discovery of a novel and new class of cholinesterase inhibitors as potential therapeutics for Alzheimer's disease. A series of novel isoalloxazine derivatives were synthesized and biologically evaluated for their potential inhibitory outcome for both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). These compounds exhibited high activity against both the enzymes AChE as well as BuChE. Of the synthesized compounds, the most potent isoalloxazine derivatives (7m and 7q) showed IC50 values of 4.72 μM and 5.22 μM respectively against AChE; and, 6.98 μM and 5.29 μM respectively against BuChE. These two compounds were further evaluated for their anti-aggregatory activity for β-amyloid (Aβ) in presence and absence of AChE by performing Thioflavin-T (ThT) assay and Congo red (CR) binding assay. In order to evaluate cytotoxic profile of these two potential compounds, cell viability assay of SH-SY5Y human neuroblastoma cells was performed. Further, to understand the binding behavior of these two compounds with AChE and BuChE enzymes, docking studies have been reported.
CuBr-Catalyzed Oxidation/Coupling: An Efficient and Applicable Strategy for the Synthesis of 2-Aryl Benzimidazoles from 1-Fluoro-2-nitrobenzene and Benzylamines
Mirza, Behrooz,Zeeb, Mohsen
supporting information, p. 534 - 540 (2015/10/29)
A novel and efficient route has been developed for the synthesis of benzimidazole derivatives via ligand-free CuBr-catalyzed oxidation and cyclization of 1,2-diamines derived from 1-fluoro-2-nitrobenzene and different arylamines as starting materials. GRAPHICAL ABSTRACT.
