- Facile synthesis and antimicrobial properties of 2-(substituted- benzylsulfanyl)-1H-benzimidazoles
-
A simple and convenient procedure for the preparation of 2-benzylthiobenzimidazoles by the reaction of 2-mercaptobenzimidazole and benzyl bromides in acetone/potassium carbonate condition has been reported and the compounds were screened for their potenti
- Kumar, Ramanatham Vinod,Gopal, Kotarkonda Raja,Seshu Kumar, Kotha V. S. R.
-
-
Read Online
- Benzimidazole derivatives as novel inhibitors for the corrosion of mild steel in acidic solution: Experimental and theoretical studies
-
The inhibition effects of three kinds of benzimidazole derivatives (2-mercaptobenzimidazole (MBI), 2-thiobenzylbenzimidazole (TBBI) and 1-butyl-2-thiobenzylbenzimidazole (BTBBI)) on the corrosion of mild steel in 1 M HCl solution were studied by weight loss and electrochemical measurements, and theoretical calculations. It is found that these compounds act as mixed type inhibitors with predominant cathodic effectiveness and exhibit high inhibition efficiencies with the order: BTBBI > TBBI > MBI. Molecular dynamics simulations reveal that these benzimidazole derivatives adsorb on Fe (1 1 0) surface in flat orientation. The theoretical calculations are in good accordance with the weight loss and electrochemical measurements.
- Zhang,Hou,Hou,Liu
-
-
Read Online
- Transition-metal-free synthesis of imidazobenzothiazines via domino C-S/C-N bond formation
-
The carbon-heteroatom bond formation is an important research field. Transition-metal-free synthesis of medicinally important heterocycles avoids products of transition metal contamination, and thus it is an environmentally friendly and cost-saving proces
- Tu, Xingzhao,Zhou, Lihong,Li, Zhijie,Lei, Ning,Zeng, Qingle
-
-
Read Online
- Expression, Purification, and Comparative Inhibition of Helicobacter pylori Urease by Regio‐Selectively Alkylated Benzimidazole 2‐Thione Derivatives
-
The urease enzyme has been an important target for the discovery of effective pharmacological and agricultural products. Thirteen regio‐selectively alkylated benzimidazole‐2‐thione derivatives have been designed to carry the essential features of urease i
- Amer, Mohamed R.,Eissa, Ibrahim H.,El Ashry, El Sayed H.,Elkaeed, Eslam B.,Elshobaky, Ahmed,Hafez, Elsayed E.,Khalid, Asaad,Metwaly, Ahmed M.,Mohammed, Salih Osman
-
-
- Design, synthesis, and evaluation of different scaffold derivatives against NS2B-NS3 protease of dengue virus
-
The number of deaths or critical health issues is a threat in the infection caused by Dengue virus, which complicates the situation, as only symptomatic treatment is the current solution. In this regard we have targeted the dengue protease NS2B-NS3 that is responsible for the replication. The series was designed with the help of molecular modeling approach using docking protocols. The series comprised of different scaffolds viz. cinnamic acid analogs (CA1–CA11), chalcone (C1–C10) and their molecular hybrids (Lik1–Lik10), analogs of benzimidazole (BZ1-BZ5), mercaptobenzimidazole (BS1-BS4), and phenylsulfanylmethylbenzimidazole (PS1-PS4). Virtual screening of various natural phytoconstituents was employed to determine the interactions of designed analogs with the residues of catalytic triad in the active site of NS2B-NS3. We have further synthesized the selected leads. The synthesized analogs were evaluated for the cytotoxicity and NS2B-NS3 protease inhibition activity and compared with known anti-dengue natural phytoconstituent quercetin as the standard. CA2, BZ1, and BS2 were found to be more potent and efficacious than the standard quercetin as evident from the protease inhibition assay.
- Ganji, Lata R.,Gandhi, Lekha,Musturi, Venkataramana,Kanyalkar, Meena A.
-
p. 285 - 301
(2020/11/19)
-
- Tandem Double-Cross-Coupling/Hydrothiolation Reaction of 2-Sulfenyl Benzimidazoles with Boronic Acids
-
A new tandem palladium-catalyzed reaction involving a Suzuki-Miyaura coupling, a desulfenylative coupling, and a hydrothiolation of a triple bond is reported. Notably, the desulfenylative coupling occurs without copper(I) assistance and the hydrothiolatio
- Lopes, Alexandra Basilio,Choury, Mickael,Wagner, Patrick,Gulea, Mihaela
-
supporting information
p. 5943 - 5947
(2019/08/26)
-
- New Strategy of the Synthesis of 3,4-Dihydropyrimido[1,2-a]benzimidazol-2(1H)-ones
-
A new procedure has been developed for preparative synthesis of 3,4-dihydropyrimido[1,2-a]-benzimidazol-2(1H)-ones by thermal intramolecular heterocyclization of 3-[2-(propylsulfanyl)- and 2-(benzylsulfanyl)-1H-benzimidazol-1-yl]propanehydrazides and 3-[2-(benzylsulfanyl)-1H-benzimidazol-1-yl]-propanamide.
- Kharaneko
-
p. 1363 - 1368
(2018/11/21)
-
- One-Pot Synthesis of 2-Benzyl/2-Allyl-Substituted Thiobenzoazoles Using Transition-Metal-Free Conditions in Water
-
A transition-metal-free protocol for the one-pot synthesis of 2-benzyl/2-allyl-substituted thiobenzoazoles in water was developed. The cyclization of 2-aminothiophenols, 2-aminophenols, and 1,2-phenylenediamines with tetramethylthiuram disulfide (TMTD) gave mercapto benzoheterocycles, and the subsequent C-S coupling with benzyl or allyl halides furnished the desired products in good to excellent yields. This method features transition-metal-free conditions with water as a solvent, an easy performance, mild reaction conditions, a wide substrate scope, and good to excellent yields, thus paving an efficient and useful way to establish a library of potentially active drug molecules.
- Zhang, Shi-Bo,Liu, Xing,Gao, Ming-Yuan,Dong, Zhi-Bing
-
p. 14933 - 14941
(2019/01/04)
-
- Zinc oxide catalyzed solvent-free mechanochemical route for C-S bond construction: A sustainable process
-
A zinc oxide catalyzed solvent-free mechanochemical process has been developed for the rapid construction of C-S bonds by using a nucleophilic substitution reaction (SN2 mechanism) that involves a variety of thiols and phenacyl/ benzyl/alkyl bromides. Notable advantages of this method in-clude its broad substrate scope, clean reaction profile, safety, scalability, high product yields at ambient conditions, and the recyclability of the catalyst. Furthermore, the prepared compounds are valuable building blocks for the synthesis of various biologically active molecules.
- Md. Khaja Mohinuddin,Gangi Reddy
-
p. 1207 - 1214
(2017/12/07)
-
- Synthesis of 2-Alkoxy/Thioalkoxy Benzo[d]imidazoles and 2-Thione Benzo[d]imidazoles via a Phase-Based, Chemoselective Reaction
-
2-Alkoxy/thioalkoxy benzo-[d]-imidazole and 2-thione benzo-[d]-imidazole libraries were constructed in solution phase and on solid phase, respectively. The key step in this work is the phase-based chemoselective reaction of the 2-mercaptobenzo-[d]-imidazole intermediate with benzyl chloride (solution phase) and Merrifield resin (solid phase). In the solution-phase case, benzyl chloride reacted with the thiol group of 2-mercaptobenzo-[d]-imidazole, whereas in the solid-phase case, Merrifield resin was introduced at an internal amine group of benzo-[d]-imidazole. To afford the desired 2-alkoxy/thioalkoxy benzo-[d]-imidazole analogues, we used various alkyl halides, alcohols, and thiols in solution phase, and to obtain 2-thione benzo-[d]-imidazole derivatives on solid phase, we used diverse alkyl halides and boronic acids. Finally, to measure the drug potential to be orally active and the molecular diversity in three-dimensional (3D) space, we calculated physicochemical properties and displayed energy-minimized 3D structures. As a result, the libraries from solution phase and solid phase show distinct features in physicochemical properties and skeletal diversities in 3D space.
- Yoon, Hyo-Jeong,Yang, Seung-Ju,Gong, Young-Dae
-
p. 738 - 747
(2017/12/18)
-
- Benign and efficient preparation of thioethers by solvent-free S-alkylation of thiols with alkyl halides catalyzed by potassium fluoride on alumina
-
The preparation of thioethers by S-alkylation of various thiols with alkyl halides under solvent-free reaction conditions using potassium fluoride on alumina (KF/Al2O3) as a solid catalyst has been investigated in detail with respect to three different modes of reaction activation (ultrasound irradiation, microwave irradiation, and conventional heating) for obtaining maximum yield of the thioether. The importance of KF/Al2O3 as a particularly efficient catalyst was corroborated for all three modes of reaction activation, although the reaction time was found to be strongly dependent on the mode of activation. The yield of the thioethers was also found to depend on the amount of the solid catalyst relative to the equimolar amounts of the two reactants.
- Nguyen, Kha Ngoc,Duus, Fritz,Luu, Thi Xuan Thi
-
p. 349 - 360
(2016/06/01)
-
- Synthesis and crystal structures of benzimidazole-2-thione derivatives by alkylation reactions
-
Alkylated, benzylated and bromoalkylated benzimidazole-thione that intramolecularly heterocyclized to 3,4-dihydro-2H-[1,3]thiazino[3,2-a]benzimidazole were synthesized. The chemical structure of the synthesized product was characterized by Infra Red, 1H-NMR, 13C-NMR, and Mass spectroscopy. Furthermore, the molecular structures of 8 and 9 were confirmed by X-ray single crystallography in different space groups, Pbca and P21/c, respectively.
- El Ashry, El Sayed H.,Kilany, Yeldez El,Nahas, Nariman M.,Barakat, Assem,Al-Qurashi, Nadia,Ghabbour, Hazem A.,Fun, Hoong-Kun
-
-
- Highly efficient tandem syntheses of unsymmetrically substituted isomeric S,N-disubstituted-2-mercaptobenzimidazoles
-
Highly efficient tandem syntheses of unsymmetrically substituted isomeric S,N-disubstituted-2-mercaptobenzimidazoles have been developed. The structures of 6a-d and isomeric compounds 9a-d have been synthesized from 2-mercaptobenzimidazole using tandem synthesis. The structures of 6a-d and isomeric compounds 9a-d have been established by spectral and analytical data, and by unambiguous syntheses.
- Rao, S. Srinivas,Reddy, Ch Venkata Ramana,Dubey
-
p. 829 - 832
(2015/06/30)
-
- The activity of magnesium/aluminum 'memory effect' reconstructed hydrotalcites in the microwave-assisted synthesis of 2-benzimidazolethiol and its alkylated derivatives
-
An efficient and practical methodology for the microwave-assisted synthesis of 2-benzimidazolethiol from 1,2-benzenediamine and carbon disulfide using reconstructed hydrotalcite is described. The corresponding mono- and dialkylated derivatives of 2-benzimidazolethiol were obtained generally in good to excellent yields after short reaction times. Reconstructed hydrotalcite proved to be an efficient and reusable heterogeneous base for the alkylation reactions. Georg Thieme Verlag Stuttgart New York.
- Cruz-Gonzalez, Deysi Y.,González-Olvera, Rodrigo,Angeles-Beltrán, Deyanira,Negrón-Silva, Guillermo E.,Santillan, Rosa
-
p. 3281 - 3287
(2013/12/04)
-
- TAPC-catalyzed synthesis of thioethers from thiols and alcohols
-
A new synthesis of thioethers is described. The reaction of aryl alcohols with aryl, heteroaryl, and alkyl thiols in the presence of TAPC as an efficient catalyst affords good to excellent yields of thioethers. Furthermore, the reaction proceeds under metal-free and solvent-free conditions thus represents an interesting complement to known methods for thioether synthesis. A plausible mechanism for this reaction is delineated. Georg Thieme Verlag Stuttgart · New York.
- Bahrami, Kiumars,Khodaei, Mohammad Mehdi,Khodadoustan, Nayere
-
experimental part
p. 2206 - 2210
(2011/10/09)
-
- S-benzimidazolyl glycosides as a platform for oligosaccharide synthesis by an active-latent strategy
-
Doing the Biz: The S-benzimidazolyl (SBiz) anomeric moiety is a new leaving group that can be activated for glycosylation under a variety of conditions, including metal-assisted and alkylation pathways. Application of a substituted SBiz moiety (X=anisoyl, see picture) allows active-latent and armed-disarmed types of oligosaccharide assembly. Copyright
- Hasty, Scott J.,Kleine, Matthew A.,Demchenko, Alexei V.
-
scheme or table
p. 4197 - 4201
(2011/07/07)
-
- Synthesis of newer bioactive 2-mercapto benzimidazoles
-
A new series of 2-mercaptobenzimiclazoles bearing 1,2.4-triazoie, 1,3,4-thiadiazole and 1,3,4-oxadiazole was synthesized through multistep reactions. IR, NMR and mass spectral data elucidated the structures of all the newly synthesized heterocycles. Invitro antimicrobial activities of title compounds were investigated against Gram positive bacterium Staphylococcus aureus. Gram negative bacterium Escherichia coli and fungus Aspergillus nigerby cup plate method, interestingly all the compounds exhibited promising antibacterial and antifungal activities.
- Umarani,Ilango,Mishra, Arun Kumar,Rabik Raja, R. Mohamed
-
p. 347 - 350
(2013/09/24)
-
- TAPC-promoted oxidation of sulfides and deoxygenation of sulfoxides
-
Figure presented. 1,3,5-Triazo-2,4,6-triphosphorine-2,2,4,4,6,6- tetrachloride (TAPC) was found to be an efficient promoter for the oxidation of sulfides and deoxygenation of sulfoxides. Excellent yields, short reaction time, easy and quick isolation of the products, solvent-free process, and excellent chemoselectivity are the main advantages of this procedure.
- Bahrami, Kiumars,Khodaei, Mohammad M.,Sheikh Arabi, Mehdi
-
supporting information; experimental part
p. 6208 - 6213
(2010/11/04)
-
- Synthesis and antimicrobial activity of certain benzimidazole and fused benzimidazole derivatives
-
Novel benzimidazole and fused benzimidazole derivatives such as triazinobenzimidazoles 3a-f, oxadia-zolylthio-methyl-l//-benzimidazoles 5a-e, triazolylthiomethyl-l//-benzimidazoles 7a,b, thiazolidinyl-methyl-l//- benzimidazoles 9a-e and pyrimidopyrrolobenzimidazoles 12a.b have been synthesized via several reactions of the key intermediate 2-chloromethyl-l//- benzimidazole with various reagents. Moreover, triazinobenzimidazoles 15a-c have been prepared starting with 2-cyanomethyl-l//-benzimidazole. Finally, another series of oxadiazoles 21a.b and triazoles 23a.b linked to benzimidazole moiety at one position have been synthesized starting with 2-mercapto-l//- benzimidazole. The structures of the newly synthesized compounds have been confirmed on the basis of elemental analysis and spectral studies. Some of the newly synthesized compounds exhibit significant antimicrobial activity, the most active compound is 21a.
- Eisa, Hassan M,Barghash, Alaa-Eldin M,Badr, Sahar M,Farahat, Abdelbasset A
-
scheme or table
p. 1515 - 1525
(2011/02/25)
-
- Computational studies and reactivity of nucleophiles in benzylation reactions
-
The nucleophilic substitution reactions of benzyl bromide using 2-mercapto benzimidazole, 2-mercaptobenzoxazole and 2-mercaptobenzothiazole as nucleophiles have been studied in methanol and acetone media. The higher reactivity of 2-mercaptobenzimidazole is attributed to the presence of two nitrogen atoms holding a pair of electrons on either side of the >C=S group. The heat of formation, ΔHf, computed from AM1 studies indicates that the reactivity of the nucleophiles is related to ΔHf, and HOMO-LUMO gap of the nucleophile.
- Ranga Reddy,Kalyani,Rajeswara Rao,Manikyamba
-
p. 236 - 239
(2008/09/18)
-
- Correlation analysis in the benzylation of sulfur nucleophiles
-
In the nucleophilic substitution reaction of benzyl bromides with three sulfur nucleophiles a linear relationship between the nucleophile discrimination parameter (s) and the Hammett substituent constant (σ) is observed.
- Kalyani,Manikyamba
-
p. 115 - 116
(2008/02/02)
-
- Solvation models in the reaction between benzyl bromide and 2-mercapto benzimidazole - A kinetic study
-
The reaction between benzyl bromide and 2-mercapto benzimidazole has been studied in different protic and aprotic solvents. The reaction is first order each with respect to [benzyl bromide] and [2-mercapto benzimidazole]. Correlation analysis of rate data shows that, the solvent parameters polarity (Y), hydrogen bond donor ability (a), and π* simultaneously influence the rate of the reaction. From the regression analysis, the information about the mode of solvation of the reactants and the transition state is obtained. The product obtained, 2-benzyl mercapto benzimidazole is proposed to form due to the proton elimination from the N-H group.
- Kalyani,Manikyamba
-
-
- Synthesis and preliminary evaluation of benzimidazole derivatives as antimicrobial agents
-
A series of 2-alkylsulphanylbenzimidazoles was synthesised and the compounds were evaluated for their in vitro antimicrobial activity. The structures of the compounds were confirmed by 1H-NMR and IR data, and their purity by elemental analysis. Antimycobacterial activities against Mycobacterium tuberculosis and non-tuberculous mycobacteria as well as antifungal activities against Candida albicans, Candida tropicalis, Candida krusei, Candida glabrata, Trichosporon beigelii, Trichophyton mentagrophytes and Aspergillus fumigatus were expressed as the corresponding MIC values. The substances exhibited appreciable antimycobacterial activity, in particular, against non-tuberculous mycobacteria. The activity of the most active compound in the set, 3,5-dinitro derivative 4t, exceeded that of the standard isoniazide against M. kansasii and M. avium. The antifungal activities of the compounds were relatively low. A weak antifungal effect was observed against the dermatophyte Trichophyton mentagrophytes. None of the compounds showed significant inhibitory activity against yeasts.
- Klimesova, Vera,Koci, Jan,Pour, Milan,Stachel, Jiri,Waisser, Karel,Kaustova, Jarmila
-
p. 409 - 418
(2007/10/03)
-
- Synthesis and spectral characterization of 2-mercaptobenzimidazole derivatives using a new active phase transfer reagent under PTC conditions
-
The phase transfer catalyzed synthesis of 2-Mercaptobenzimidazole derivatives using the new active phase transfer reagent namely, 2- benzilidine-N,N,N,N',N',N'-hexaethyl propane-1,3-diammonium dibromide (Dq-Br) have been described. The structures of all the fifteen compounds have been established by spectroscopic means.
- Jayachandran, J. Paul,Wang, Maw-Ling
-
p. 4087 - 4099
(2007/10/03)
-
- A New Synthetic Method for the 2-Substitution of N-Unsubstituted Benzimidazoles: Formaldehyde as a Versatile Protecting Agent for Heterocyclic NH
-
N-Unsubstituted benzimidazoles 1 are readily converted in a one-pot sequence into 2-substituted derivatives 2 with good overall yields.N-Protection with formaldehyde and lithiation with lithium N,N-diisopropylamide (LDA), n-butyllithium, or tert-butyllithium gives the dilithiohemiaminals 6, which readily react with a range of electrophiles at the 2-carbon.The 2-substituted 1-(lithioxymethyl)benzimidazoles 7 undergo smooth acid-catalyzed dehydroxymethylation under mild conditions to give N-unsubstituted 2-substituted benzimidazoles 2.
- Katritzky, Alan R.,Akutagawa, Kunihiko
-
p. 2949 - 2952
(2007/10/02)
-
- Fission of 1,2,4-Thiadiazol-3-ones by Triphenylphosphane: Triphenylphosphonio Thioimidazolates and Their Consecutive Reactions
-
Treatment of benzimidazothiadiazol-3(2H)-ones (1) and imidazothiadiazol-3(2H)-ones (17) with triphenylphosphan leads to the liberation of isocyanate and the formation of triphenylphosphonio-thiobenzimidazolat (4) and triphenylphosphonio-thioimidazolat (18), respectively. 2,4-Diphenyl-5-phenylimino-1,2,4-thiadiazol-3-one (23) is desulfurized with Ph3P and decomposed into phenyl isocyanate and diphenylcarbodiimide whereas the N-unsubstituted imino-thiadiazol-3-one (25) is attacked at the exocyclic imino group by Ph3P to give the N-phosphoranylidene thiourea (26).The structure of 4 can be rationalized as a dynamic system between polar and apolar valence isomeres.Reactions of 1 and 17 with cyanates, isocyanates, carbon disulfide, acetic anhydride, amines, benzyl chloride, grignard compounds, and CH acidic compounds are described.
- Tittelbach, Franz,Martin, Dieter
-
p. 338 - 348
(2007/10/02)
-
- Synthesis and Spectral Studies of 2-Mercaptobenzimidazole Derivatives. II.
-
This communication describes synthesis and spectral data of new 2-mercaptobenzimidazole derivatives.
- Suri, O.P.,Khajuria, R.K.,Saxena, D.B.,Rawat, N.S.,Atal, C.K.
-
p. 813 - 814
(2007/10/02)
-