Home About us Contact
|
Home About us Contact | ||
|
|
||
Thiazolo
Selected AbstractsFacile Synthesis and In-Vitro Antitumor Activity of Some Pyrazolo[3,4- b]pyridines and Pyrazolo[1,5- a]pyrimidines Linked to a Thiazolo[3,2- a]benzimidazole MoietyARCHIV DER PHARMAZIE, Issue 1 2010Hatem A. Abdel-Aziz Abstract The key precursor E -3-(N,N -dimethylamino)-1-(3-methylthiazolo[3,2- a]benzimidazol-2-yl)prop-2-en-1-one 4 was synthesized in good yield using Gold's reagent. The reaction of enaminone 4 with 5-amino-3-aryl-1 - phenylpyrazoles 5a, b in refluxing acetic acid in the presence of sulphuric acid, yielded pyrazolo[3,4- b]pyridines 7a, b. Similarly, pyrazolo[1,5- a]pyrimidines 10a, b and 14a,f were prepared by reaction of enaminone 4 with 5-amino-1H -pyrazoles 8a, b and 12a,f, respectively. The structure of pyrazolo[1,5- a]pyrimidine 10b was determined by X-ray diffraction. The synthesized compounds were tested for their in-vitro antitumor activity against the colon cancer cell line CaCo-2; their cytotoxicity against the normal fibroblast cell line BHK was explored as well. Some of the tested compounds exhibited cell growth inhibitory activity. The significant antitumor activity of compound 14f against the CaCo-2 cell line (IC50 = 0.5 ,g/mL) was coupled with a lower toxicity against BHK (IC50 = 2.3 ,g/mL). [source] ChemInform Abstract: One-Step Synthesis of Thiazolo[3,2-a]pyridines by a Multicomponent Reaction of ,-Enaminonitriles, ,,,-Unsaturated Aldehydes, and 2-Aminothiol Hydrochlorides.CHEMINFORM, Issue 35 2010Monica Perez-Perrino Abstract Although the synthetic interest for the multicomponent preparation of the title thiazolopyridines is evident, the stereochemical control is rather low. [source] ChemInform Abstract: Green Chemoselective Synthesis of Thiazolo[3,2-a]pyridine Derivatives and Evaluation of Their Antioxidant and Cytotoxic Activities.CHEMINFORM, Issue 8 2010Feng Shi 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: A Convenient Route to New Pyrrolo[1,2-c]pyrimidone, Thiazolo[3,4-c]pyrimidone and Pyrimido[4,5-d]pyridazine Derivatives.CHEMINFORM, Issue 33 2009Nabila A. Kheder 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] ChemInform Abstract: Synthesis of Thiazolo[4,5-d]pyridines.CHEMINFORM, Issue 50 2008Viktor O. Iaroshenko 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] ChemInform Abstract: Synthesis and Antimicrobial Activity of Some New Pyrazolo[3,4-d]pyrimidines (IV) and Thiazolo[4,5-d]pyrimidines (VI).CHEMINFORM, Issue 30 2008J. D. Akbari 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] ChemInform Abstract: Synthesis of New 1,3,8-Trisubstituted Purine-2,6-diones and 1,3,6-Trisubstituted Thiazolo[2,3-f]purine-2,4-diones.CHEMINFORM, Issue 25 2008Alaa M. Hayallah 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] ChemInform Abstract: Influence of the Structures of ,-Halo Ketones and Thioamides on the Hantzsch Synthesis of Thiazoles and Thiazolo[5,4-b]indoles.CHEMINFORM, Issue 22 20084-b]indole., A New Approach to 4-Acetyl-2-methyl-4H-thiazolo[ 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] ChemInform Abstract: A Novel, One-Pot, Three-Component Synthesis of 5H-[1,3]Thiazolo[3,2-a]pyrimidine Derivatives.CHEMINFORM, Issue 10 2008Mehdi Adib 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] ChemInform Abstract: Synthesis of Some 1,3-Thiazole, 1,3,4-Thiadiazole, Pyrazolo[5,1-c]-1,2,4-triazine, and 1,2,4-Triazolo[5,1-c]-1,2,4-triazine Derivatives Based on the Thiazolo[3,2-a]benzimidazole Moiety.CHEMINFORM, Issue 2 2008Nehal A. Hamdy 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] Synthesis of Thiazolo[3,2-d][1,2,4] Triazines Through Palladium-Catalyzed Heteroannulation of Acetylenic Compounds.CHEMINFORM, Issue 38 2007Majid M. Heravi 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] Design and Synthesis of Some New Thiazolo[3,2-b]-1,2,4-triazole-5(6H)-ones Substituted with Flurbiprofen as Antiinflammatory and Analgesic Agents.CHEMINFORM, Issue 33 2007Emine Dogdas 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] Synthesis of Chiral Thiazolo[3,4-a]pyrazine-5,8-diones.CHEMINFORM, Issue 35 2006Teresa M. V. D. Pinho e Melo 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] Regioselectivity in Diels,Alder Reactions of Thiazolo[3,2-d][1,4,2]diazaphospholes and Related Compounds.CHEMINFORM, Issue 24 2005Raj K. Bansal Abstract For Abstract see ChemInform Abstract in Full Text. [source] A New Route to Partially Hydrogenated Thiazolo[3,2-a]pyridine.CHEMINFORM, Issue 8 2005A. D. Dyachenko Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthesis of 2,3-Dihydro-1,3,4-thiadiazole, Thiazole, and Thiazolo[4,3-a]pyrimidine Derivatives from Ethyl Benzoylacetate.CHEMINFORM, Issue 32 2004Nora M. Rateb Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthesis of 3,3,-Bi-1,2,4-triazolo[4,5-a]benzimidazole, 5,5,-Bi-1,3,4-thiadiazole, and Thiazolo[3,2-a]benzimidazole Derivatives.CHEMINFORM, Issue 13 2004Kamal M. Dawood Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthesis and Antitumor Evaluation of New Polysubstituted Thiazole and Derived Thiazolo[4,5-d]pyrimidine Systems.CHEMINFORM, Issue 44 2002Hesham T. Y. Fahmy Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: Gas-Phase Pyrolysis of 4-Amino-3-allylthio-1,2,4-triazoles: A New Route to [1,3]Thiazolo[3,2-b][1,2,4]triazoles.CHEMINFORM, Issue 30 2001Dale D. J. Cartwright 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: Synthesis and Spectroscopic Studies of Some Hydrogenated Thiazolo[2,3-a]isoquinolines.CHEMINFORM, Issue 30 2001Maria D. Rozwadowska 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: Heterocyclic Systems Containing Bridgehead Nitrogen Atom: Synthesis and Bioactivity of Thiazolo[3,2-b]-s-triazoles and Isomeric Thiazolo[2,3-c]-s-triazoles.CHEMINFORM, Issue 23 2001Jag Mohan 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] Synthesis of [1,2,4]Oxadiazolo[4,5- a]thiazolo[2,3- b]pyrimidin-9(10H)-ones via 1,3-Dipolar Cycloaddition of Nitrile Oxide to Thiazolo[3,2- a]pyrimidin-3-one DerivativesCHINESE JOURNAL OF CHEMISTRY, Issue 6 2010Xiaofang Li Abstract A new class of [1,2,4]oxadiazolo[4,5- a]thiazolo[2,3- b]pyrimidin-9(10H)-one was prepared in moderate yields by the reaction of nitrile oxide with 2-arylmethylidene-6,7-dihydro-5H -thiazolo[3,2- a]pyrimidin-3-one. The reaction site of dipolarphile is the CN of thiazolo[3,2- a]pyrimidin-3-one rather than the expected CC of arylmethylidene. The structures of the products were characterized thoroughly by IR, elemental analysis, MS, and NMR analysis. [source] Promising antimicrobial agents: Synthetic approaches to novel tricyclic and tetracyclic pyrimidinones with antimicrobial propertiesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2010Hatem M. Gaber New tricyclic pyrimidinone derivatives were obtained from the corresponding thiazolopyrimidinone or hydrazino systems. The annelation of tricyclic hydrazino compound with 1,2,4-triazole and tetrazole moieties gave novel tetracyclic condensed pyrimidinones. The investigation of the antimicrobial properties of tricyclic and tetracyclic pyrimidinones, by agar-well diffusion assay, was carried out against six pathogenic bacteria (Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Klebsiella spp, and Salmonella typhyrium) and four pathogenic fungi (Aspergillus flavus, Aspergillus niger, Aspergillus fumigatus, and Trichderma horozianum). Most of the compounds tested exhibited some degree of antimicrobial activity against microorganisms. Among these compounds, 4-benzylidenhydrazino-8-cyano-7-(furan-2-yl)thiazolo[3,2- a:4,5- d,]dipyrimidin-9-one (12) showed the most favorable antibacterial activity, while compound 17 showed the highest effect on fungi. Interestingly, tetrazole derivative 19 displayed a remarkable effect on fungi much more than the corresponding 3-substituted triazole derivatives on the one hand, whereas the lowest effect on bacteria on the other. J. Heterocyclic Chem., (2010). [source] Preparation of halogenated derivatives of thiazolo[5,4- d]thiazole via direct electrophilic aromatic substitutionJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2008Vladimir Benin Chlorination and bromination reactions of thiazolo[5,4- d]thiazole led to the generation of its mono- and dihalogenated derivatives. These are the first instances of successful direct electrophilic aromatic substitution in the thiazolo[5,4- d]thiazole ring system. X-ray analysis demonstrates that both 2-bromothiazolo[5,4- d]-thiazole and 2,5-dibromothiazolo[5,4- d]thiazole are planar structures, with strongly manifested ,-stacking in the solid state. Theoretical analysis of the pyridine-catalyzed halogenation (MP2/6-31+G(d) and B3LYP/6-31+G(d) calculations) reveals that introduction of one halogen actually leads to a slightly enhanced reactivity towards further halogenation. Several halogenation mechanisms have been investigated: 1) The direct C-halogenation with N-halopyridine as electrophile; 2) C-halogenation via intermediate N-halogenation, and 3) C-halogenation following an addition - elimination pathway, with intermediate formation of a cyclic halonium ion. The theoretical studies suggest that the direct C-halogenation is the favored mechanism. [source] Synthesis, characterization and studies of new 3-benzyl-4H -1,2,4-triazole-5-thiol and thiazolo[3,2- b][1,2,4]triazole-5(6H)-one heterocyclesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2008Abdelwareth A. O. Sarhan 3-Benzyl-4-phenyl-1,2,4-triazole-5-thiol (1) was synthesized and used as starting material for preparation of 1,2,4-triazole bearing substituted thiosemicarbazides moiety (4a-d) in high yields. The thiosemicarbazides 4a-d were cyclized in basic medium to give two triazole rings linked by thiomethylene group (5a-d), while cyclization of thiosemicarbazides 4a-d with chloroacetyl chloride in the presence of CHCl3 and K2CO3 afforded the thiazolidinone derivatives 6a-d. The reaction of thiosemicarbazides 4a-c with phenacyl bromide in the presence of EtOH and fused CH3COONa gave the corresponding thiazoline ring systems 7a-c. Condensation of the 3-benzyl-1,2,4-triazole-5(1H)-thiol (1) with chloroacetic acid and aromatic aldehydes (8a- g) in boiling acetic acid/acetic anhydride mixture in the presence of fused sodium acetate gave one single isomer only, which might be 9a-g or 10a-g. Upon application of Micheal addition reaction on compounds 9a-e with cyclic secondary amines such as piperidine or morpholine the 2-benzyl-6-(,-amino-aryl/methyl)-1,3-thiazolo[3,2- b][1,2,4]-triazol-5-ols (11a-j) were obtained in good yields The structure of all new compounds were determined using both spectral and elemental analyses. [source] Synthesis of thiazolo[3,2- d][1,2,4] triazines through palladium-catalyzed heteroannulation of acetylenic compoundsJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2007Majid M. Heravia The reaction of 6-methyl-5-(prop-2-ynylthio)-5,6-dihydro-1,2,4-triazin-3(4H)-one 1 with various iodobenzenes 2 in the presence of palladium catalyst leads to the formation of substituted triazolotriazines. [source] New access to thiazolo[4,5- d]pyrimidine derivativessJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2006M. Bakavoli 4-Amino-5-bromo-2-substituted-aminopyrimidines are readily obtained from the newly prepared 5-bromo-2,4-dichloro-6-methylpyrimidine by sequential treatment with ethanolic ammonia and secondary amines. These compounds were successfully reacted with various isothiocyanates in the presence of sodamide in DMF to form the new thiazolo[4,5- d] pyrimidine derivatives. [source] Generation and reactivity of 3-carbethoxy-5-phenyl- 5H,7H -thiazolo[3,4- c]oxazol-4-ium-1-olateJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 4 2004Teresa M. V. D. Pinho e Melo 3-Carbethoxy-5-phenyl-5H,7H -thiazolo[3,4- c]oxazol-4-ium-1-olate was generated from (2R,4R)- N -ethoxyoxalyl-2-phenylthiazolidine-4-carboxylic acid and its reactivity studied. This münchnone showed low reactivity as dipole although from the reaction with dimethyl acetylenedicarboxylate the corresponding (3R)-3-phenyl-17H,3H -pyrrolo[1,2- c]thiazole-5,6,7-tricarboxylate could be isolated. The thermolysis of (2R,4R)- N -ethoxyoxalyl-2-phenylthiazolidine-4-carboxylic acid in refluxing acetic anhydride led to the synthesis of N -(1-ethoxycarbonyl-2-phenylvinyl)-2-phenyl-4-thioxo-1,3-thiazolidine. The structure of methyl (2R,4R)- N -ethoxyoxalyl-2-phenylthiazoliddine-4-carboxylate was determined by X-ray crystallography. [source] Synthesis of 2-amino-4h -thiazolo[5,4- b]indole and characterization of its colored conversion products with protein tyrosine phosphatase inhibitory activityJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2001Jens Breinholt In DMSO-solution 2-amino-4H -thiazolo[5,4- b]indole is converted into a complex mixture of colored products. The three major conversion end-products, of which two are inhibitors of protein tyrosine phos-phatases (PTPs), were isolated by chromatographic methods and their structures characterized by spectro-scopic analysis, including NMR and MS combined with computer assisted structure elucidation, and, finally, confirmed by independent chemical synthesis. Synthesis of 2-amino-4H -thiazolo[5,4- b]indole as well as its N -acetyl derivatives prepared from either oxindole or 2-bromo-1-(2-nitro-phenyl)ethanone is described. [source] Synthesis and electroluminescent properties of fluorene-based copolymers containing electron-withdrawing thiazole derivativesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2008In Hwan Jung Abstract We synthesized two fluorene-based copolymers poly[(2,5-bis(4-hexylthiophen-2-yl)thiazolo[5,4-day]thiazole-5,5,-diyl)-alt-(9,9,-dioctylfluorene-2,7-diyl)] (PF-TTZT), and poly[(5,5,-bis(4-hexylthiophen-2-yl)-2,2,-bithiazole-5,5,-diyl)-alt-(9,9,-dioctylfluorene-2,7-diyl)] (PF-TBTT), which contain the electron-withdrawing moieties, thiazolothiazole, and bithiazole, respectively. Through electrochemical studies, we found that these two polymers exhibit stable reversible oxidation and reduction behaviors. Moreover, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of PF-TBTT are lower than those of PF-TTZT, and the bandgap of PF-TBTT is smaller than that of PF-TTZT. Thus the bithiazole moiety in PF-TBTT is more electron-withdrawing than the thiazolothiazole moiety in PF-TTZT. Light-emitting devices with indium tin oxide (ITO)/poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate)(PEDOT)/polymer/bis(2-methyl-8-quinolinato)-4-phenylphenolate aluminum (BAlq)/LiF/Al configurations were fabricated. The performance of the PF-TBTT device was found to be almost three times better than that of the PF-TTZT device, which is because electron injection from the cathode to PF-TBTT is much easier than for PF-TTZT. We also investigated the planarity and frontier orbitals of the electron donor-acceptor (D-A) moieties with computational calculations using ab initio Hartree,Fock with the split-valence 6-31G* basis set. These calculations show that TBTT has a more nonplanar structure than TTZT and that the bithiazole moiety is more electron-withdrawing than thiazolothiazole. These calculations are in good agreement with the experimental results. © Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7148,7161, 2008 [source] | ||||||||||||||||||||||