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Imidazole Derivatives (imidazole + derivative)
Selected AbstractsSynthesis of Chiral Imidazole Derivatives as Purine PrecursorsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 6 2003Jerzy Suwi Abstract From commercially available chiral building blocks, we have developed methods for the syntheses of imidazole derivatives that contain a chiral alkyl substituent at ring atom. These compounds are suitable for further transformation into Nalkyl purine derivatives. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Synthesis of Imidazole Derivatives with Antimycobacterial ActivityARCHIV DER PHARMAZIE, Issue 1 2010Pedro O. Miranda Abstract 4-Substituted 1-(p -methoxybenzyl)imidazoles were designed and synthesized in order to mimic parts of the structure of highly potent antimycobacterial 6-aryl-9-(p -methoxybenzyl)purines. 4-Haloimidazoles were subjected to Pd-catalyzed cross-coupling in order to introduce a (hetero)aryl group, or they were converted to Grignard reagents and reacted with (hetero)arylaldehydes. Further transformations of the adducts gave a variety of potential antimycobacterials with different "spacers" between the imidazole and (hetero)aryl group. The adduct from furfural was rearranged to a cyclopentenone derivative when treated with methanol under acidic conditions. Several target compounds exhibited antimycobacterial activity in vitro (IC90 13 ,g/mL for the best inhibitors), but they were not as active as the most potent purines and pyrimidines synthesized before. [source] ChemInform Abstract: The First Example of a Diastereoselective Thio-Ugi Reaction: A New Synthetic Approach to Chiral Imidazole Derivatives.CHEMINFORM, Issue 8 2008Anton V. Gulevich Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] An Iminophosphorane-Based Approach for the Synthesis of Spiropyrrolidine,Imidazole Derivatives.CHEMINFORM, Issue 23 2007Pilar M. Fresneda Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Isoprene-Catalyzed Lithiation: Deprotection and Functionalization of Imidazole Derivatives.CHEMINFORM, Issue 20 2007Rosario Torregrosa Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] ChemInform Abstract: Unusual Methylene Transfer in Reactions of Simmons,Smith Reagent with 1,3-Diazabuta-1,3-dienes: Synthesis of Functionalized Imidazole Derivatives.CHEMINFORM, Issue 32 2002S. Jayakumar Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: N-Alkylation of 2,4,5-Triphenyl Imidazole Derivatives Using a New Phase Transfer Reagent under PTC Conditions.CHEMINFORM, Issue 1 2002Joseph Paul Jayachandran Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Design and Synthesis of 1-(4-Benzoylphenyl)imidazole Derivatives as New Potent 20-HETE Synthase Inhibitors.CHEMINFORM, Issue 9 2005Toshio Nakamura Abstract For Abstract see ChemInform Abstract in Full Text. [source] On the Way to Glycoprocessing Inhibitors , Synthesis of an Imidazolo-Nectrisine-Phosphono Acid Derivative: A Potential Glycosyltranferase InhibitorEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 15 2003Théophile Tschamber Abstract Assuming the transition state of glycosyltransferase inhibitors to be similar to those encountered with potent glycosidase inhibitors , i.e. a flattened conformation with a positively charged anomeric centre , we worked out a synthesis of the D - arabino -configured phosphonic acid target molecule 2 derived from an imidazolo-sugar. The key synthetic intermediate is the linear imidazolo L - xylo compound 10 which could be obtained, either from L - threo precursor 6 by a coupling reaction with imidazole derivative 5, or from L -sorbose. A multi-step and site specific iodination of 10 gave the mono-iodo- L - xylo derivative 14 which was cyclised to the D - arabino -configured bicyclic azasugar 15. Phosphorylation of the Grignard derivative of the latter, followed by mono-esterification with citronellol along with some protection-deprotection steps led to target molecule 2. The potential inhibitor 2 is supposed to be protonated at its most basic N atom by a carboxylic acid residue in the arabinosyl-transferase active site. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Ring Opening of 1-Azabicyclo[1.1.0]butanes with Hydrazoic Acid , a Facile Access to N -Unsubstituted Azetidin-3-AminesHELVETICA CHIMICA ACTA, Issue 7 2005Grzegorz Mlosto Sterically congested 1-azabicyclo[1.1.0]butanes 1 add hydrazoic acid smoothly at 0,5°, giving 3-azidoazetidines 2 in good to excellent yields. After hydrogenolysis over Pd/C catalyst, compounds 2 were converted into N -unsubstituted azetidin-3-amines 4. Attempted reduction of 2a with Raney -Ni led to a mixture of the expected azetidin-3-amine 4a and the ring-enlarged 2,5-dihydro-1H -imidazole derivative 5. [source] Curing mechanisms and kinetic analysis of DGEBA cured with a novel imidazole derivative curing agent using DSC techniquesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2010Li Liu Abstract A novel imidazole derivative, 2MI- g -CA, was obtained through the reaction of 2-methylimidazole (2MI) and cyanuric acid (CA) and characterized by means of elemental analysis, FTIR spectroscopy, 1H NMR spectroscopy, and mass spectrometric analysis. The curing mechanisms and kinetics of diglycidyl ether of bisphenol A (DGEBA) using 2MI and 2MI- g -CA as curing agents were studied with differential scanning calorimetry (DSC) under dynamic and isothermal conditions. Both dynamic and isothermal DSC thermograms of DGEBA/2MI system showed two distinct exothermic peaks, whereas those of DGEBA/2MI- g -CA system showed only one distinct exothermic peak. These results indicated that the two systems have different initiation curing mechanisms. The apparent activation energies (Ea) obtained from DSC scanning runs using the Kissinger and Ozawa methods were 79.0, 83.0 kJ/mol and 84.2, 88.8 kJ/mol for DGEBA/2MI and DGEBA/2MI- g -CA systems, respectively. These values suggested the novel curing agent 2MI- g -CA exhibited greater levels of latency during cure or increased the pot life of epoxy resin system. In addition, under the same curing condition, the Tg values of DGEBA/2MI- g -CA system were about 25°C higher than those of DGEBA/2MI system, exhibiting a better thermal stability. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Chiral separation of N -imidazole derivatives, aromatase inhibitors, by cyclodextrin-capillary zone electrophoresis.ELECTROPHORESIS, Issue 16 2004Mechanism of enantioselective recognition Abstract Baseline separation of ten new, substituted [1-(imidazo-1-yl)-1-phenylmethyl)] benzothiazolinone and benzoxazolinone derivatives with one chiral center was achieved using cyclodextrin-capillary zone electrophoresis (CD-CZE). A method for the enantiomeric resolution of these compounds was developed using neutral CDs (native ,-, ,-, ,-CDs or ,-, ,-, ,-hydroxypropyl (HP)-CDs) as chiral selectors. Operational parameters including the nature and concentration of the chiral selectors, pH, ionic strength, organic modifiers, temperature, and applied voltage were investigated. The use of neutral CDs provides enantiomeric resolution by inclusion of compounds in the CD cavity. The HP-,-CD and HP-,-CD were found to be the most effective complexing agents and allowed efficient enantiomeric resolutions. Optimal separation of N -imidazole derivatives was obtained using 50 mM phosphate buffer at pH 2.5 containing either HP-,-CD or HP-,-CD (7.5,12.5 mM) at 25°C, with an applied field of 0.50 kV·cm,1 giving resolution factors Rs superior to 1.70 with migration times of the second enantiomer less than 13 min. The same enantiomer migration order observed for all molecules can be related to a close interaction mechanism with CDs. The influence of structural features of the solutes on Rs and tm was studied. The lipophilic character (log kw) of the solutes and the apparent and averaged association constants of inclusion complexes for four compounds with the six different CDs led us to rationalize the enantioseparation mechanisms. The conclusions were corroborated with reversed-phase high-performance liquid chromatography (HPLC) on chiral stationary phases (CSPs) based on CDs. [source] Synthesis of Chiral Imidazole Derivatives as Purine PrecursorsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 6 2003Jerzy Suwi Abstract From commercially available chiral building blocks, we have developed methods for the syntheses of imidazole derivatives that contain a chiral alkyl substituent at ring atom. These compounds are suitable for further transformation into Nalkyl purine derivatives. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Novel tetracyclic imidazole derivatives: Synthesis, dynamic NMR study, and anti-inflammatory evaluationJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2010Renata Rup A series of tetracyclic imidazole derivatives 9a,9v and 10a,10h are prepared by multistep route starting from the known tricyclic diketones 2a,2d. Intermediary dibenzooxepin[4,5- d]imidazoles (3a, 3c) and dibenzothiepin[4,5- d]imidazoles (3b, 3d) are N -protected to 4e, 4f and to the isomeric compounds 5a, 5b and 6a, 6b. The isomeric compounds 5 and 6 are separated. Compounds 4, 5, and 6 are formylated at C(2) to afford 7a,7j. In the last steps, aldehyde group is reduced, then alkylated to the two sets of isomeric ,-dimethylaminoalkyl derivatives 9a,9v. N -deprotection of 9i,9v led to the compounds 10a,10h. Assignment of the syn/anti structure to 5a and 6a was supported by 1D selective ROESY NMR spectra, whereas conformational mobility for the selected representatives 8a and 8b is studied by dynamic NMR. Activation energies (energy barriers for interconversion) are determined to be ,11.5 and 16.2 kcal/mol, respectively. A series of derivatives 9 and 10 were tested in vitro for their anti-inflammatory activity. J. Heterocyclic Chem., (2010). [source] Synthesis of new imidazole derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 4 2008Krystyna Nowak The derivatives of 1-propyl- and 1-butyl- of 2-methyl-5-nitroimidazole containing phenylpiperazine, m -chloro- and o -methoxyphenylpiperazine attached at the end of alkyl chain were synthesed. For the obtained new compounds, the biological activity was predicted using the computer program PASS. [source] Cyano,cyano and chloro,cyano interactions in two imidazole derivativesACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2004Maciej Kubicki In two closely related 1-aryl-2-methyl-4-nitro-5-cyanoimidazoles, namely 2-methyl-4-nitro-1-phenyl-1H -imidazole-5-carbonitrile, C11H8N4O2, and 1-(4-chlorophenyl)-2-methyl-4-nitro-1H -imidazole-5-carbonitrile, C11H7ClN4O2, different weak intermolecular interactions determine the crystal packing. In the 1-phenyl derivative, dipole,dipole interactions between antiparallel cyano groups connect molecules into centrosymmetric dimers, while in the 1-(4-chlorophenyl) derivative, the dimers are connected by C,N,Cl,C halogen bonds. These interactions, together with weak C,H,O(N) hydrogen bonds, connect molecules related by subsequent centres of inversion into infinite tapes. [source] | ||||||||||