15728-44-6Relevant articles and documents
Lewis acid mediated, mild C-H aminoalkylation of azolesviathree component coupling
Emmert, Marion H.,He, Cyndi Qixin,Shah, Akshay A.,Felten, Stephanie
, p. 3890 - 3897 (2021)
This manuscript reports the development of a mild, highly functional group tolerant and metal-free C-H aminoalkylation of azolesviaa three-component coupling approach. This method enables the C-H functionalization of diverse azole substrates, such as oxazoles, benzoxazoles, thiazoles, benzothiazoles, imidazoles, and benzimidazoles. DFT calculations identify a key deprotonation equilibrium in the mechanism of the reaction. Using DFT as a predictive tool, the C-H aminoalkylation of initially unreactive substrates (imidazoles/benzimidazoles) can be enabled through anin situprotecting/activating group strategy. The DFT-supported mechanistic pathway proposes key interactions between the azole substrate and the Lewis acid/base pair TBSOTf/EtNiPr2that lead to azole activation by deprotonation, followed by C-C bond formation between a carbene intermediate and an iminium electrophile. Two diverse approaches are demonstrated to explore the amine substrate scope: (i) a DFT-guided predictive analysis of amine components that relates reactivity to distortion of the iminium intermediates in the computed transition state structures; and (ii) a parallel medicinal chemistry workflow enabling synthesis and isolation of several diversified products at the same time. Overall, the presented work enables a metal-free approach to azole C-H functionalizationviaLewis acid mediated azole C-H deprotonation, demonstrating the potential of a readily available, Si-based Lewis acid to mediate new C-C bond formations.
Phenyliodine diacetate-mediated intramolecular C(sp2)-H amidation for 1,2-disubstituted benzimidazole synthesis under metal-free conditions
Maiti, Saikat,Mal, Prasenjit
, p. 1416 - 1424 (2015)
A transition metal-free, hypervalent iodine(III) reagent [phenyliodine diacetate (PIDA)]-mediated C(sp2)-H amidation in trifluoroethanol (TFE) has been developed. The intramolecular coupling methodology presented here provides a direct access t
Electrochemical Oxidative Amination of Sodium Sulfinates: Synthesis of Sulfonamides Mediated by NH4I as a Redox Catalyst
Jiang, Yang-Ye,Wang, Qing-Qing,Liang, Sen,Hu, Li-Ming,Little, R. Daniel,Zeng, Cheng-Chu
, p. 4713 - 4719 (2016)
An efficient protocol for the synthesis of sulfonamides via the electrochemical oxidative amination of sodium sulfinates has been developed. The chemistry proceeds in a simple undivided cell employing a substoichiometric amount of NH4I that serves both as a redox catalyst and a supporting electrolyte; in this manner additional conducting salt is not required. A wide range of substrates, including aliphatic or aromatic secondary and primary amines, as well as aqueous ammonia, proved to be compatible with the protocol. Scale-up was possible, thereby demonstrating the practicality of the approach. The electrolytic process avoids the utilization of external oxidants or corrosive molecular iodine and therefore represents an environmentally benign means by which to achieve the transformation.
A facile and versatile electro-reductive system for hydrodefunctionalization under ambient conditions
Huang, Binbin,Guo, Lin,Xia, Wujiong
supporting information, p. 2095 - 2103 (2021/03/26)
A general electrochemical system for reductive hydrodefunctionalization is described, employing the inexpensive and easily available triethylamine (Et3N) as a sacrificial reductant. This protocol is characterized by facile operation, sustainable conditions, and exceptionally wide substrate scope covering the cleavage of C-halogen, N-S, N-C, O-S, O-C, C-C and C-N bonds. Notably, the selectivity and capability of reduction can be conveniently switched by simple incorporation or removal of an alcohol as a co-solvent.
Facile access to: N-formyl imide as an N-formylating agent for the direct synthesis of N-formamides, benzimidazoles and quinazolinones
Huang, Hsin-Yi,Liang, Chien-Fu,Lin, Xiu-Yi,Yen, Shih-Yao
supporting information, p. 5726 - 5733 (2020/08/21)
N-Formamide synthesis using N-formyl imide with primary and secondary amines with catalytic amounts of p-toluenesulfonic acid monohydrate (TsOH·H2O) is described. This reaction is performed in water without the use of surfactants. Moreover, N-formyl imide is efficiently synthesized using acylamidines with TsOH·H2O in water. In addition, N-formyl imide was successfully used as a carbonyl source in the synthesis of benzimidazole and quinazolinone derivatives. Notable features of N-formylation of amines by using N-formyl imide include operational simplicity, oxidant- A nd metal-free conditions, structurally diverse products, and easy applicability to gram-scale operation.
Electron Transfer Photoredox Catalysis: Development of a Photoactivated Reductive Desulfonylation of an Aza-Heteroaromatic Ring
Qiang-Liu,Liu, Yu-Xiu,Song, Hong-Jian,Wang, Qing-Min
supporting information, p. 3110 - 3115 (2020/07/04)
Herein, we report a protocol for desulfonylation of aza-heteroaromatic rings via photoinduced electron transfer and hydrogen atom transfer. This general protocol has a wide substrate range and moderate to good yields. The utility of the method was demonstrated by the chemoselective desulfonylation of a molecule containing both an aliphatic and an aromatic sulfonamide. (Figure presented.).
Cu-catalyzed dehydrogenative olefinsulfonation of Alkyl arenes
Li, Fangfang,Zhang, Guang'an,Liu, Yingguo,Zhu, Bingke,Leng, Yuting,Wu, Junliang
supporting information, p. 8791 - 8795 (2020/11/30)
A copper-catalyzed reaction protocol for the dehydrogenation of ethylbenzenes into styrene derivatives has been developed. This reaction procedure proceeded well under mild reaction conditions, providing a practical and efficient strategy for the rapid assembly of biologically and pharmaceutically significant molecules, such as vinyl sulfone. Simple alkyl arenes were functionalized via consecutive β-elimination in the presence of N-sulfonylbenzo[d]imidazole with broad substrate scope and good functional group tolerance.
Design, synthesis and molecular docking studies of novel N-arylsulfonyl-benzimidazoles with anti Trypanosoma cruzi activity
Miana, Gisele E.,Ribone, Sergio R.,Vera, Domingo M.A.,Sánchez-Moreno, Manuel,Mazzieri, María R.,Quevedo, Mario A.
, p. 1 - 10 (2019/01/15)
Currently, only two drugs (i.e. benznidazole (BZN) and nifurtimox (NFX)) have been approved for the treatment of Trypanosoma cruzi (Tc) infection, the etiological agent causing Chagas disease. Since both drugs exhibit severe side effects, patients frequently abandon therapy, resulting in an inefficient pharmacotherapeutic treatment. In this context, there is an urgent need to develop new, safer and optimised anti-Tc agents. In this report, we present the synthesis and biological activity of 11 novel and 3 already reported N-arylsulfonyl-benzimidazole derivatives (NBSBZD,1–14) currently in development as potential anti-Tc compounds. These compounds were designed as part of a library of synthetic arylsulfonyl heterocycle derivatives constructed from privileged structures exhibiting drug-like properties. Based on bioactivity assays against Tc, (in both the extracellular and intracellular forms), we observed that 10 compounds exhibited bioactivity against the epimastigote form, while six of them exhibited activity against the amastigote counterpart. Also, the compounds showed less cytotoxicity compared to the reference drug BZN as measured in Vero cell culture. In order to elucidate the potential mechanism of action, metabolite excretion profiles studies were performed, and complemented with molecular modeling studies performed over known Tc druggable targets. Consistency was observed between experimental and theoretical findings, with metabolic profiles showing that compounds 1, 2, 9, 12 and 14 interfered with the normal glycolysis cycle of Tc, while molecular modeling studies were able to establish a solid structure-activity relationship towards the inhibition of 6-phospho-1-fructokinase, a key enzyme involved in the parasite glycolytic cascade. Overall, the present study constitutes a multidisciplinary contribution to the development of new anti-Chagas compounds.
Molecular modeling, synthesis, antibacterial and cytotoxicity evaluation of sulfonamide derivatives of benzimidazole, indazole, benzothiazole and thiazole
Naaz, Farha,Srivastava, Ritika,Singh, Anuradha,Singh, Nidhi,Verma, Rajesh,Singh, Vishal K.,Singh, Ramendra K.
, p. 3414 - 3428 (2018/05/23)
A new series of heterocyclic molecules bearing sulfonamide linkage has been synthesized and screened for antibacterial activity. During antibacterial screening using broath dilution method, molecules were found to be highly active (MIC value 50–3.1 μg/mL)
Synthesis, characterization, antitumor, antibacterial and urease inhibitory activity of a small series of N-tosyl benzimidazoles
Rashid, Naghmana,Kiran, Almas,Ashraf, Zaman,Bhatti, Moazzam Hussain,Mirza, Bushra,Ismail, Hammad,Rafiq, Muhammad,Jasinski, Jerry P.
, p. 366 - 374 (2018/06/06)
Benzimidazole derivatives exhibited a broad range of biological activities, e.g., antimicrobial, antiviral, anthelmintic, anti-inflammatory, anticancer and as an anti-ulcer/proton pump inhibitor. Keeping in view the large number of reported drugs containing benzimidazole moiety on one hand and sulfonamide on the other hand, a small series of N-tosyl benzimidazoles (4a-e) have been synthesized. The present work describes the synthesis, characterization and bio-evaluation of five new N-tosyl benzimidazoles with the objective to develop new compounds with improved anticancer, antibacterial and urease inhibitory activities. The substituted 1,2-phenylenediamines in the first step were condensed with aliphatic carboxylic acids to synthesize the substituted benzimidazoles. In the second step the tosyl chloride was reacted with substituted benzimidazoles in basic conditions to afford the title N-tosyl benzimidazoles (4a-e). The screening for their antitumor activities was performed against Agrobacterium tumefaciens by following the potato disc tumor assay. The compound (4e) exhibited excellent antitumor activity with IC50 values 474.45μgml-1 compared to other synthesized compounds. Antibacterial activity results revealed that compounds 4d and 4e having methyl and ethyl substitution respectively at the imidazole ring showed excellent zone inhibition against both gram positive and gram negative strains. The urease inhibitory activity results showed that derivative 4e exhibited highest potential to inhibit the urease enzyme compared to all other derivatives. Based upon our investigation it is proposed that compound (4e) may serve as lead structure to design more potent biological active compounds having multitargets inhibition activities.
