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Synthesis of a new class of triazole-linked benzoheterocycles via 1,3-dipolar cycloaddition
Barbosa, Fernanda C. G;Oliveira, Ronaldo N. de;
Journal of the Brazilian Chemical Society , 2011, DOI: 10.1590/S0103-50532011000300025
Abstract: a new series of 1,2,3-triazole derivatives have been synthesized from phthalimides and terminal alkynes in the presence of a catalytic amount of cui. the present protocol affords 1,2,3-triazoles in moderate to good yields (44-89%)
Synthesis of new triazole arotinoids analogues via "Click Chemistry" with potential anticancer activity Síntese de novos análogos triazólicos arotinoidais via “Click Chemistry” com potencial atividade anticancer  [cached]
Mariana A. A. Aleixo,Tais M. Garcia,Tatiana C. Bortolo,Diego B. Carvalho
Orbital : the Electronic Journal of Chemistry , 2012,
Abstract: Retinoids are a class of natural and synthetic vitamin A analogues structurally related to all-trans-retinoic acid (ATRA). This class of compounds can inhibit cell proliferation and induce differentiation and apoptosis of cells, and several are used in cancer therapy. Using the concept of bioisosterism, new triazole analogues were designed from the molecular modification of the potent derivative arotinoid AM580. This compound has an amide grouping which is a bioisostere of 1,2,3-triazole ring. Through "Click Chemistry” approach, triazole analogues were obtained by reaction of Huisgen 1,3-dipolar cycloaddition between aryl azides and terminal acetylene, previously synthesized. The reagents used were CuI, triethylamine and mixture of ethanol:water. The first compound synthesized showed anticancer activity, while the second proved to be inactive. The molecular docking results showed that both compounds have high affinity for the retinoid RARα receptor (related to anticancer activity), but probably the second compound has antagonist activity on this receptor. Os retinoides s o análogos naturais e sintéticos da vitamina A, estruturalmente relacionados ao ácido trans-retinoico (ATRA). Esta classe de compostos pode inibir a prolifera o celular e induzir a diferencia o e apoptose das células, sendo vários deles usados na terapia do cancer. Utilizando o conceito de bioisosterismo, os novos análogos triazólicos foram planejados a partir da modifica o molecular do potente derivado arotinoidal AM580. Este possui um grupamento amida que é um bioisóstero de anéis 1,2,3-triazólicos. Através da abordagem “Click Chemistry”, os análogos triazólicos foram obtidos pela rea o de cicloadi o 1,3 dipolar de Huisgen entre o acetileno terminal e as azidas, previamente sintetizados. Como reagentes foram utilizados o CuI, a trietilamina e mistura de etanol:água. O primeiro composto sintetizado apresentou atividade anticancer, enquanto o segundo mostrou ser inativo. Os resultados de docking molecular mostraram que os dois compostos possuem alta afinidade pelo receptor retinoide RARα (relacionado à atividade anticancer), porém, o segundo composto provavelmente possui atividade antagonista sobre este receptor.
Environ-Economic Synthesis and Characterization of Some New 1,2,4-Triazole Derivatives as Organic Fluorescent Materials and Potent Fungicidal Agents  [PDF]
Harshita Sachdeva,Rekha Saroj,Sarita Khaturia,Diksha Dwivedi
Organic Chemistry International , 2013, DOI: 10.1155/2013/659107
Abstract: A multicomponent one-pot clean cyclocondensation reaction of 4-chloro-2-nitro aniline/amino acids and aromatic aldehydes/indole-2,3-diones with thiosemicarbazide in water yielding triazole/spiro indole-triazole derivatives in high yields and shorter reaction time and displaying excellent florescent property is reported. The developed MCR may provide a valuable practical tool for the synthesis of new drugs containing the title core fragment. All the newly synthesized compounds have been characterized by IR, 1HNMR, 13CNMR, and fluorescence study and also been screened for antimicrobial activity. 1. Introduction Multicomponent and domino reactions are efficient and effective methods in the sustainable and diversity-oriented synthesis of heterocycles and such reactions have attracted enormous interest in recent years [1]. Thiosemicarbazide and its derivatives are an important class of synthetic compounds, having large variety of applications due to their wide spectrum of biological activities [2] including antiviral [3] and antitumoral [4] as well as parasiticidal activity against Plasmodium falciparum, Plasmodium berghei [5], Trypanosoma cruzi [6–8] Trypanosoma brucei rhodesiense [9], and Toxoplasma gondii [10]. The 1,2,4-triazoles and their derivatives are found to be associated with various biological activities such as anticonvulsant [11], antifungal [12], anticancer [13], antiinflammatory [14], and antibacterial properties [15]. Also several compounds containing 1,2,4-triazole rings are well known as drugs; for example, fluconazole is used as an antimicrobial drug, while vorozole, letrozole, and anastrozole are nonsteroidal drugs used for the treatment of cancer. The increasing diversity of small molecule libraries is an important source for the discovery of new drug candidates. In terms of this trend, the literature survey showed that indole derivatives possess anticancer [16, 17], antioxidant [18], antibacterial [19], antifungal [20, 21], antiviral [22, 23], and antihypertensive activities [24]. Indole-3-carbon atom in the form of spiro carbon atom exhibits enhanced biological activities [25, 26]. The important biological activities of triazole derivatives impelled us to take up the synthesis of these new combinational heterocycles which are likely to have augmented diverse biological activity. The developed MCR may provide a valuable practical tool for the synthesis of novel physiologically active agents containing the title core fragment. Several methods [27–30] for the synthesis of 1,2,4-triazole derivatives are reported in the literature but all
Synthesis and pharmacological evaluation of isoxazole derivatives containing 1,2,4-triazole Moiety  [cached]
Shantaram Khanage,Popat Mohite,Ramdas Pandhare,Appala Raju
Marmara Pharmaceutical Journal , 2012,
Abstract: A new class of isoxazole derivatives containing 1,2,4-triazole moiety were synthesized to meet structural requirements essential for antibacterial, antimycobacterial and anticancer activity. 1-(3,5-dipheny-1H-1,2,4-triazole-1-yl) ethanone (compound 2) was treated with different aromatic aldehydes to get substituted chalcones (3a-g) then subsequently cyclized with hydroxyl amine hydrochloride to yield 1-[5-(substituted aryl)-1,2-oxazol-3-yl]- 3,5-diphenyl-1H-1,2,4-triazoles (4a-g). IR, 1H-NMR, Mass spectra and elemental analysis were recorded to confirm the structures of target compounds. Compound 3a-g and 4a-g were screened for in vitro antimicrobial activity against B. subtillis NCIM 2063, E. coli NCIM 2065, C. albicans NCIM 3471 and A. niger NCIM 1196. MIC values were determined by liquid broth method. Chloro, nitro, methoxy substituted derivatives exhibited significant antibacterial and fungicidal potential. The in vitro antimycobacterial activity of the compounds 4a-g against Mycobacterium tuberculosis H37Rv was evaluated. The highest inhibition was observed through compound 4f as 76% at >6.25 μg/ml. Among the synthesized isoxazole derivatives, five compounds have been selected and evaluated for their anticancer activity at the National Cancer Institute for testing against a panel of approximately 60 different human tumor cell lines derived from nine neoplastic cancer types. The most efficient anticancer compound 4e was found to be active with selective influence on leukemia cancer cell lines, especially on SR with a growth % of 71.72.
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.
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.
Synthesis and X-Ray Structure of New Anticancer Nucleosides Based on 1-((2-Hydroxyethoxy)methyl)-5-(phenylthio)-1H-1,2,4-triazole-3-carboxamide  [PDF]
Yulong Lei, Dehua Zhang, Yang Liu, Guanghui Tian, Hongguang Ge
Journal of Crystallization Process and Technology (JCPT) , 2014, DOI: 10.4236/jcpt.2014.43017
A pair of new anticancer nucleosides based on 1,2,4-triazole nucleosides and 1-((2-hydroxyethoxy) methyl)-5-(phenylthio)-1H-1,2,4-triazole-3-carboxamide have been synthesized, and have given the corresponding products in excellent yields. Its structures and conformations were confirmed by single crystal X-ray diffraction.
Production of Podophyllotoxin by Immobilized Cell Cultures of Juniperus chinensis
Duangporn Premjet,Sanro Tachibana
Pakistan Journal of Biological Sciences , 2004,
Abstract: In the present study immobilized cell cultures of Juniperus chinensis were developed using various calcium alginate gel concentrations (1.8, 3 and 6% w/v). The podophyllotoxin productivity of immobilized cell cultures was compared with that for free cell suspension cultures. The free cell suspension cultures accumulate podophyllotoxin in intracellular compartments, while the immobilized cells with calcium alginate excrete marked amounts of podophyllotoxin into the culture media. From the effect of immobilization components on free cell suspension cultures, it was considered that the calcium alginate gel was supposed to be act as an elicitor and forced the cells to release the product into the culture media. The amount of podophyllotoxin excreted depends on the alginate gel concentration used: 3% calcium alginate gel promoted podophyllotoxin production through 28 days of cultivation. The podophyllotoxin production by immobilized cell cultures entrapped with the 3% calcium alginate gel was enhanced to 4 mg g-1 dry weight.
Antibacterial Activity of Synthetic Precursors of Podophyllotoxin  [cached]
N. Nanjundaswamy,S. Satish,K. M. Lokanatha Rai,S. Shashikanth
International Journal of Biomedical Science , 2007,
Abstract: Precursors of podophyllotoxin were synthesized and screened for their antibacterial activity. The results proved that ethyl-2-(3′-methyl-4′-methoxybenzoyl)-3-(4′′ methoxyphenol)-cyclopropane-1-carboxylic acid and Ethyl-2-(3′-methyl-4′-methoxybenzyol-3-1 3″, 4″-dimethoxyphenyl)-cyclopropane-carboxylic acid have significant antibacterial activity against Citrobacter sp., Escherchia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, Shigella sonnei and Streptococcus faecalis. The activity is lower than Ciprofloxacin and equal to Gentamicin and more than Penicillin and Streptomycin.
Design, synthesis and structural studies of meta-xylyl linked bis-benzimidazolium salts: potential anticancer agents against ‘human colon cancer’
Rosenani A Haque, Muhammad Iqbal, Mohamed B Khadeer Ahamed, AMS Majid, Zena A Abdul Hameed
Chemistry Central Journal , 2012, DOI: 10.1186/1752-153x-6-68
Abstract: A number of N-alkylbenzimidazoles were synthesized by reactions of benzimidazole with alkyl halides (i-PrBr, PrBr, EthBr, Pent-2-ylBr, BuBr, BenzCl, HeptBr). The subsequent treatment of the resulting N-alkylbenzimidazoles with 1,3-(bromomethylene)benzene afforded corresponding bis-benzimidazolium salts. All synthesized compounds were characterized by spectroscopic techniques (Additional file 1: NMR & FT-IR) and microanalysis. Molecular structures of selected compounds were established through single crystal x-ray diffraction studies. All the compounds were assessed for their anti-proliferation test on human colorectal cancer cell line (HCT 116). Results showed that the compounds exhibited dose dependent cytotoxicity towards the colon cancer cells with IC50 ranges between 0.1 to 17.6 μM. The anti-proliferation activity of all compounds was more pronounced than that of standard reference drug 5-flourouracil (IC50 =19.2 μM).All the synthesized bis-benzimidazolium salts showed potential anticancer activity. Out of them, some of these salts showed IC50 value as low as 0.1–0.2 μM. Based on the results it can be concluded that, the bis-benzimidazolium salts could probably be the potential source of chemotherapeutic drugs.New drugs to fight cancer are constantly needed. Colon cancer (bowel cancer) is a cancer caused by uncontrolled cell growth in the colon, rectum, or vermiform appendix. It is the third most common cancer and the fourth most frequent cause of cancer deaths worldwide [1]. Every year, more than 945000 people develop colorectal cancer worldwide, and around 492000 patients die [1].Benzimidazole is a heterocyclic moiety possessing wide spectrum of biological activities [2]. The biological importance of benzimidazole derivatives is due to their structural resemblance to the naturally occurring nucleotides, which allow them to interact with the biopolymers of the living system [2]. In the last decade some benzimidazole derivatives have shown some potential antican
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