38423-40-4Relevant academic research and scientific papers
Two-step synthetic route to 10-substituted isoalloxazines
Chattopadhyay, Prosenjit,Rai, Roopali,Pandey, Pramod S.
, p. 1857 - 1861 (2006)
10-Substituted isoalloxazines were synthesized in two steps starting from 1,2-phenylenediamine. Monoalkylation of the diamine resulted in 2-amino-N-alkylanilines, which were subsequently condensed with alloxan in boric acid and acetic acid to give 10-subs
Synthesis of 1,2-disubstituted benzimidazoles through DDQ-oxidized intramolecular dehydrogenative coupling of N,N′-dialkyl o-phenylenediamines
Feng, Yangyang,Ma, Youcai,Xiong, Ruimei,Xiong, Yan,Zhang, Xiaohui
supporting information, (2020/09/02)
The synthetic methodology of 1,2-disubstituted benzimidazoles has been developed, which starts from N,N′-dialkyl o-phenylenediamines via intramolecular dehydrogenative coupling under the oxidation of DDQ with mild conditions. Through detailed optimization of reaction conditions, only DDQ was found essential without any additives to reach to the highest yield of 99%. In the cases of linear aliphatic substituents, the synthesis of 1-alkyl-2-phenylbenzimidazoles showed high selectivities and their structures were identified by 2D NMR COSY correlation analysis. A plausible mechanism was proposed to interpret the observed reactivities and selectivities.
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.
Synthesis and photophysical properties of ruthenium(ii) polyimine complexes decorated with flavin
Guo, Huimin,Zhu, Lijuan,Dang, Can,Zhao, Jianzhang,Dick, Bernhard
, p. 17504 - 17516 (2018/07/06)
A bipyridine ruthenium(ii) complex (Ru-1) with a flavin moiety connected to one of the bipyridine ligands via an acetylene bond was designed and synthesized, and its photophysical properties were investigated. Compared with the tris(bipyridine) Ru(ii) com
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 Benzimidazole–Quinolone Hybrids as New Cleaving Agents toward Drug-Resistant Pseudomonas aeruginosa DNA
Wang, Ya-Nan,Bheemanaboina, Rammohan R. Yadav,Gao, Wei-Wei,Kang, Jie,Cai, Gui-Xin,Zhou, Cheng-He
, p. 1004 - 1017 (2018/04/30)
A series of benzimidazole–quinolone hybrids as new potential antimicrobial agents were designed and synthesized. Bioactive assays indicated that some of the prepared compounds exhibited potent antibacterial and antifungal activities. Notably, 2-fluorobenzyl derivative 5 b (ethyl 7-chloro-6-fluoro-1-[[1-[(2-fluorophenyl)methyl]benzimidazol-2-yl]methyl]-4-oxo-quinoline-3-carboxylate) showed remarkable antimicrobial activity against resistant Pseudomonas aeruginosa and Candida tropicalis isolated from infected patients. Active molecule 5 b could not only rapidly kill the tested strains, but also exhibit low toxicity toward Hep-2 cells. It was more difficult to trigger the development of bacterial resistance of P. aeruginosa against 5 b than that against norfloxacin. Molecular docking demonstrated that 5 b could effectively bind with topoisomerase IV–DNA complexes, and quantum chemical studies theoretically elucidated the good antimicrobial activity of compound 5 b. Preliminary experimental reaction mechanism exploration suggested that derivative 5 b could not intercalate into DNA isolated from drug-resistant P. aeruginosa, but was able to cleave DNA effectively, which might further block DNA replication to exert powerful bioactivities. In addition, compound 5 b is a promising antibacterial agent with membrane disruption abilities.
Novel benzimidazolyl tetrahydroprotoberberines: Design, synthesis, antimicrobial evaluation and multi-targeting exploration
Jeyakkumar, Ponmani,Liu, Han-Bo,Gopala, Lavanya,Cheng, Yu,Peng, Xin-Mei,Geng, Rong-Xia,Zhou, Cheng-He
, p. 1737 - 1743 (2017/04/04)
A series of novel benzimidazolyl tetrahydroprotoberberines were conveniently designed and efficiently synthesized from berberine via direct cyclization of tetrahydroprotoberberine aldehyde and o-phenylene diamines under metal-free aerobic oxidation. All the new compounds were characterized by IR, 1H NMR, 13C NMR and HRMS spectra. The antimicrobial evaluation revealed that the 5-fluorobenzimidazolyl derivative 5b was the most active antibacterial and antifungal molecule with broad spectrum in comparison to Berberine, Chloromycin, Norfloxacin and Fluconazole. It triggered almost no resistance development against MRSA even after 15 passages. Further studies demonstrated that compound 5b could not only effectively interact with Topo IA by hydrogen bonds, but also intercalate into calf thymus DNA and cleave pBR322 DNA, which might be responsible for its powerful bioactivities.
Design, synthesis and biological evaluation of 5-fluorouracil-derived benzimidazoles as novel type of potential antimicrobial agents
Fang, Xue-Jie,Jeyakkumar, Ponmani,Avula, Srinivasa Rao,Zhou, Qian,Zhou, Cheng-He
, p. 2584 - 2588 (2016/05/09)
A series of 5-fluorouracil benzimidazoles as novel type of potential antimicrobial agents were designed and synthesized for the first time. Bioactive assay manifested that some of the prepared compounds exhibited good or even stronger antibacterial and an
Discovery of membrane active benzimidazole quinolones-based topoisomerase inhibitors as potential DNA-binding antimicrobial agents
Zhang, Ling,Addla, Dinesh,Ponmani, Jeyakkumar,Wang, Ao,Xie, Dan,Wang, Ya-Nan,Zhang, Shao-Lin,Geng, Rong-Xia,Cai, Gui-Xin,Zhou, Cheng-He,Li, Shuo
, p. 160 - 182 (2018/05/17)
A series of novel benzimidazole quinolones as potential antimicrobial agents were designed and synthesized. Most of the prepared compounds exhibited good or even stronger antimicrobial activities in comparison with reference drugs. The most potent compound 15m was membrane active and did not trigger the development of resistance in bacteria. It not only inhibited the formation of biofilms but also disrupted the established Staphylococcus aureus and Escherichia coli biofilms. It was able to inhibit the relaxation activity of E. coli topoisomerase IV at 10 μM concentration. Moreover, this compound also showed low toxicity against mammalian cells. Molecular modeling and experimental investigation of compound 15m with DNA suggested that this compound could effectively bind with DNA to form a steady 15m-DNA complex which might further block DNA replication to exert the powerful bioactivities.
O- and N-Alkylsubstituted 2-(2'-Hydroxyphenyl)-benzimidazoles and -1,3,4-Oxadiazoles as Complexing and Extracting Agents for Copper-II-Ions
Beger, J.,Wagner, G.,Uhlig, E.,Dinjus, U.
, p. 708 - 718 (2007/10/02)
2-(2'-Alkoxyphenyl)-benzimidazoles 1, 1-alkyl-2-(2'-hydroxyphenyl)-benzimidazoles 2, 2-(2'-hydroxy-4'-alkoxyphenyl)-benzimidazoles 3, 2-(2',4'-dialkoxyphenyl)-benzimidazoles 4 and 1-alkyl-2-(2'-hydroxy-5'-nitrophenyl)-benzimidazoles 7 are synthesized by condensation of 2-hydroxybenzoic acid derivatives and o-phenylendiamine or its derivatives.Alkyl chains (C4, C8 or C12) are introduced by alkylation before or after the ring closure in order to increase the solubility of the reagent in toluene or n-octane.Furthermore the extraction properties of the benzimidazoles are investigated.Also some new analogous compounds of the benzothiazole and the 1,3,4-oxadiazole series were synthesized.
