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New 1,2,3-Triazole Iminosugars Derivatives Using Click Chemistry  [PDF]
Chahrazed Benhaoua
International Journal of Carbohydrate Chemistry , 2012, DOI: 10.1155/2012/394574
Abstract: The click concept refers ease, efficient, and the selective chemicals transformations. In this study, a novel regiospecific copper (I)-catalyzed 1, 3-dipolar of terminal alkynes to azide provided a practicable synthetic pathway of triazole iminosugars derivatives. A series of new triazole-pyrrolidinols are reported in good yield. 1. Introduction There are considerable interests in the design of molecules that are able to mimic carbohydrates which play critical roles in various biological events. This is shown by the following example, the 1-deoxynojirimycin (DNJ) family, for which DNJ itself is a competitive inhibitor of α-D-glucosidase ( 25?μM) [1], while its derivatives Miglustat (N-nBu DNJ, Zavesa) and Miglitol (N-hydroxyethyl DNJ, Glyset, or Diastabol) have already found therapeutic applications in Gaucher’s disease [2] and type 2 (noninsulin-dependant mellitus) diabetes, respectively [3, 4] (Figure 1). Recently, researches have increasingly accorded to new iminosugars from click chemistry [5]. Figure 1: Structure of inhibitors of glycosidases. The term click chemistry was introduced by Sharpless and coworkers and promotes the use of efficient, selective, and versatile chemical reactions in synthetic chemistry [6]. The basic reaction, which is nowadays summed up under the name “Sharpless-type click reaction,” is a variant of the Huisgen 1,3-dipolar cycloaddition reaction between C–C triple bonds and alkyl azides [7, 8] (Scheme 1). Scheme 1: 1,3-dipolar cycloaddition reaction. Meldal and coworkers published a paper in 2002 that describes the acceleration of this process by CuI salts that leads to a reaction at 25°C in quantitative yields. It was mentioned that the organic azides and the terminal alkynes are united to afford 1,4-regioisomers of 1,2,3-trialoes as sole products [9]. The source of Cu(I) salts commonly used involves the reduction of copper(II) sulfate by sodium ascorbate [9], although other conditions have been described, such as Cu(I) [10] salts, Cu(I) complexes [11] and stabilized derivatives of Cu(I) [9]. The bases used are mostly triethylamine, 2,6-lutidine and N,N-diisopropylethylamine (DIPEA). 1.1. Click Chemistry and Synthesis of Iminosugars Derivatives The application of CuAAC-catalysed reactions for the synthesis of new α-glucosidase inhibitors containing a 1-deoxynojirimycin (DNJ) was described by Murphy and coworkers. These compounds indicate that it is possible to modulate the potency and the selectivity towards different glycosidases [5] (Figure 2). Figure 2: Structures of triazole iminosugars as potential glycosidase
SYNTHESIS, CHARACTERIZATION AND BIOLOGICAL EVALUATION OF TRIAZOLE AND FUSED TRIAZOLE DERIVATIVES
VORA,JABALI J; PATEL,DINESH R; BHIMANI,NILESH V; AJUDIA,PARAG V;
Journal of the Chilean Chemical Society , 2011, DOI: 10.4067/S0717-97072011000300011
Abstract: triazole and fused heterocyclic triazole derivatives like schiff bases, thiadiazoles, thiadiazepine, thiadiazine etc. were synthesized and characterized by ir, ms and 1h nmr. the triazole derivatives were evaluated for their antibacterial activity against the gram-positive bacteria b. megaterium and s. aureus, the gram-negative bacteria e. aerogenes and p. aeruginosa using dmso as a solvent.
SYNTHESIS, CHARACTERIZATION AND BIOLOGICAL EVALUATION OF TRIAZOLE AND FUSED TRIAZOLE DERIVATIVES  [cached]
JABALI J VORA,DINESH R PATEL,NILESH V BHIMANI,PARAG V AJUDIA
Journal of the Chilean Chemical Society , 2011,
Abstract: Triazole and fused heterocyclic triazole derivatives like Schiff bases, thiadiazoles, thiadiazepine, thiadiazine etc. were synthesized and characterized by IR, MS and 1H NMR. The triazole derivatives were evaluated for their antibacterial activity against the gram-positive bacteria B. megaterium and S. aureus, the gram-negative bacteria E. aerogenes and P. Aeruginosa using DMSO as a solvent.
Green Chemistry as a Versatile Technique for the Synthesis of Benzimidazole Derivatives: Review  [PDF]
Anshul Chawla,Gurpreet Kaur,Anil Kumar Sharma
International Journal of Pharmaceutical and Phytopharmacological Research , 2013,
Abstract: “Green chemistry” is the newand rapid emerging field of chemistry. It involves the utilization of a set of principles that reducesor eliminates the use or generation of hazardous substances in the design, manufacture and application of chemical products.Microwave induced organic reaction enhancement (MORE) is a simple, clean, fast, efficientandeconomical method for thesynthesis of organic molecules and has emerged as a tool towards green chemistry. This technique canreduce the time ofchemical reaction from hours to minutes. Conventional methods of synthetic reactions need longer heating time, elaborate andtedious apparatus set up which result in higher cost and environmental pollution. The reaction rateof microwave induced organicreaction increases ten to thousand times andthe yield of the product increases by 10-30 % compared to that by the conventionalmethods. As we know benzimidazole derivatives have been reported to have a wide range of pharmacological and biochemicalactivities; viz antifungal, antibacterial, antiviralanthelmintic, analgesic, anti-inflammatory, anti-neoplastic, depressive, hypnotic,anti-pyretic and anti-spasmolytic.Thus, we became interested in the study of synthesis of substituted benzimidazoles by greensynthesis techniques and furthermore to studytheir biological activities.
Green Chemistry Approach for Efficient Synthesis of Schiff Bases of Isatin Derivatives and Evaluation of Their Antibacterial Activities  [PDF]
Jnyanaranjan Panda,V. Jagannath Patro,Biswa Mohan Sahoo,Jitendriya Mishra
Journal of Nanoparticles , 2013, DOI: 10.1155/2013/549502
Abstract: Microwave-assisted organic synthesis, a green chemistry approach, is nowadays widely used in the drug synthesis. Microwave-assisted synthesis improves both throughput and turnaround time for medicinal chemists by offering the benefits of drastically reduced reaction times, increased yields, and pure products. Schiff bases are the important class of organic compounds due to their flexibility, and structural diversities due to the presence of azomethine group which is helpful for elucidating the mechanism of transformation and rasemination reaction in biological system. This novel compound could also act as valuable ligands for the development of new chemical entities. In the present work, some Schiff bases of Isatin derivatives was synthesized using microwave heating method. Schiff base of Isatin were synthesized by condensation of the keto group of Isatin with different aromatic primary amines. They were characterized by means of spectral data and subsequently subjected to the in vitro antibacterial activities against gram positive and gram negative strains of microbes. It was observed that the compound with electron withdrawing substituents exhibited good antibacterial activities against almost all the micro organisms. 1. Introduction Microwave-assisted organic synthesis is widely used as a source of heating in drug synthesis. Drug molecules can be built in a fraction of the time by this method. As a result, this technique has rapidly gained acceptance as a valuable tool for accelerating drug discovery and development processes. A microwave is a form of electromagnetic energy, which falls at the lower end of the electromagnetic spectrum and is defined in a measurement of frequency as 300 to 300,000 Megahertz. The microwave region of the electromagnetic spectrum lies between infrared and radio frequencies. The basic mechanism of microwave assisted synthesis involves agitation of polar molecules or ions that oscillate under the effect of an oscillating electric or magnetic field. In the presence of an oscillating field, particles try to orient themselves or be in phase with the field. Only materials that absorb microwave radiation are relevant to microwave chemistry. These materials can be categorized according to the three main mechanisms of heating such as dipolar polarization, conduction mechanism, and interfacial polarization. The technique offers simple, clean, fast, efficient, and economical for the synthesis of a large number of drug molecules, having provided the momentum for many medicinal chemists to switch from traditional heating method to
SYNTHESIS AND In vitro ANTIMICROBIAL ACTIVITY OF SOME TRIAZOLE DERIVATIVES
MISHRA,RAVINESH; KUMAR,RAJIV; KUMAR,SURESH; MAJEED,JASEELA; RASHID,MOHD; SHARMA,SAMEER;
Journal of the Chilean Chemical Society , 2010, DOI: 10.4067/S0717-97072010000300019
Abstract: some 4-[{1-(substituted)methylidine}-amino]-3-(4-pyridyl)-5-mercapto-4h-1,2,4-triazol (3a- 3f) and n-[5-(4-substituted)-1h-1,2,3-triazol-1-yl] isonicotinamide derivatives (5a- 5e) were synthesized by a sequence of reactions starting from isonicotinic acid hydrazide and is illustrated in scheme 1 and 2. the antibacterial and antifungal activities of newly synthesized compounds were tested by the disc diffusion method using nutrient agar medium against various microorganisms such as gram positive staphylococcus aureus and bacillus subtilis, gram negative escherichia coli and the fungi aspergillus niger and candida albicans. ciprofloxacin and fluconazole at 50 μg/ml were used as standard drugs for antibacterial and antifungal activities, respectively. all the synthesized compounds showed significant activity against various microorganisms.
SYNTHESIS AND In vitro ANTIMICROBIAL ACTIVITY OF SOME TRIAZOLE DERIVATIVES  [cached]
RAVINESH MISHRA,RAJIV KUMAR,SURESH KUMAR,JASEELA MAJEED
Journal of the Chilean Chemical Society , 2010,
Abstract: Some 4-[{1-(substituted)methylidine}-amino]-3-(4-pyridyl)-5-mercapto-4H-1,2,4-triazol (3a- 3f) and N-[5-(4-substituted)-1H-1,2,3-triazol-1-yl] isonicotinamide derivatives (5a- 5e) were synthesized by a sequence of reactions starting from isonicotinic acid hydrazide and is illustrated in scheme 1 and 2. The antibacterial and antifungal activities of newly synthesized compounds were tested by the disc diffusion method using nutrient agar medium against various microorganisms such as gram positive Staphylococcus aureus and Bacillus subtilis, gram negative Escherichia coli and the fungi Aspergillus niger and Candida albicans. Ciprofloxacin and Fluconazole at 50 μg/mL were used as standard drugs for antibacterial and antifungal activities, respectively. All the synthesized compounds showed significant activity against various microorganisms.
Synthesis of New Bis-1,2,4-Triazole Derivatives  [PDF]
Olcay Bekircan,Hakan Bektas
Molecules , 2006, DOI: 10.3390/11060469
Abstract: A series of new 1,2/1,3-bis[o-(N-methylidenamino-3-aryl-5-phenyl-4H-1,2,4-triazole-4-yl)phenoxy]ethane/propane derivatives 4 were prepared in good yields bytreatment of 4-amino-3-aryl-5-phenyl-4H-1,2,4-triazoles 2 with certain bis-aldehydes 1.Compounds 4 were reduced with NaBH4 to afford the corresponding 1,2/1,3-bis[o-(N-methylamino-3-aryl-5-phenyl-4H-1,2,4-triazole-4-yl)phenoxy]ethane/propane derivatives5. All new compounds were characterized by IR, 1H-NMR, 13C-NMR and mass spectraldata.
Synthesis and biological activity of some triazole-bearing benzimidazole derivatives  [PDF]
K. F. ANSAR,C. LAL,R. K. KHITOLIYA
Journal of the Serbian Chemical Society , 2011,
Abstract: A number of N’-(arylmethylidene)-2-(2-methyl-1H-benzimidazol-1-yl)acetohydrazide and 4-aryl-5-[(2-methyl-1H-benzimidazol-1-yl)methyl]-4H-1,2,4-triazole-3-thiol derivatives were synthesized by incorporating various aromatic and heterocyclic substituents on 2-methyl-1H-benzimidazole. The structures of all the synthesized compounds were elucidated based on their elemental analyses and spectral data. The in vitro activities of these compounds against bacteria and fungi were evaluated by the disc diffusion and the minimum inhibitory concentration (MIC) methods. Some of the synthesized derivatives were found to be as active as kanamycin (standard drug).
Synthesis and Anticancer Activity of Glucosylated Podophyllotoxin Derivatives Linked via 4β-Triazole Rings  [PDF]
Cheng-Ting Zi,Feng-Qing Xu,Gen-Tao Li,Yan Li,Zhong-Tao Ding,Jun Zhou,Zi-Hua Jiang,Jiang-Miao Hu
Molecules , 2013, DOI: 10.3390/molecules181113992
Abstract: A series of 4 β-triazole-linked glucose podophyllotoxin conjugates have been designed and synthesized by employing a click chemistry approach. All the compounds were evaluated for their anticancer activity against a panel of five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7, SW480) using MTT assays. Most of these triazole derivatives have good anticancer activity. Among them, compound 35 showed the highest potency against all five cancer cell lines tested, with IC 50 values ranging from 0.59 to 2.90 μM, which is significantly more active than the drug etoposide currently in clinical use. Structure-activity relationship analysis reveals that the acyl substitution on the glucose residue, the length of oligoethylene glycol linker, and the 4'-demethylation of podophyllotoxin scaffold can significantly affect the potency of the anticancer activity. Most notably, derivatives with a perbutyrylated glucose residue show much higher activity than their counterparts with either a free glucose or a peracetylated glucose residue.
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