55899-43-9Relevant articles and documents
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.
Novel purine benzimidazoles as antimicrobial agents by regulating ROS generation and targeting clinically resistant Staphylococcus aureus DNA groove
Wang, Ya-Nan,Bheemanaboina, Rammohan R. Yadav,Cai, Gui-Xin,Zhou, Cheng-He
supporting information, p. 1621 - 1628 (2018/03/29)
A novel series of purine benzimidazole hybrids were designed and synthesized for the first time with the aim to circumvent the increasing antibiotic resistance. Hexyl appended hybrid 3c gave potent activities against most of the tested bacteria and fungi especially against multidrug-resistant strains Staphylococcus aureus (MIC = 4 μg/mL). Structure-activity relationships revealed that the benzimidazole fragment at the 9-position of purine played an important role in exerting potentially antibacterial activity. Both cell toxicity and ROS generation assays indicated that the purine derivative 3c showed low cytotoxicity and could be used as a safe agent. Molecular modeling suggested that hybrid 3c could bind with the residues of Topo IA through hydrogen bonds and electrostatic interactions. Quantum chemical studies were also performed on the target compound 3c to understand the structural features essential for activity. The active molecule 3c could effectively interact with S. aureus DNA to form 3c–DNA complex through groove binding mode, which might block DNA replication to display their powerful antimicrobial activity.
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.
