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Thiazole Derivatives (thiazole + derivative)
Selected AbstractsAntibacterial and Antifungal Studies on Some New Acetylcinnolines and Cinnolinyl Thiazole Derivatives.CHEMINFORM, Issue 47 2006B. Narayana 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] Microwave-Induced Synthesis of 3/4-Substituted-2-thioxo/2-oxo-6-thioxo-1,2,3,4,6,7-hexahydrothiazolo [4,5-d]pyrimidine and Thiazole Derivatives.CHEMINFORM, Issue 17 2005Vijay V. Dabholkar Abstract For Abstract see ChemInform Abstract in Full Text. [source] Theoretical Study on Second-order Nonlinear Optical Properties of Substituted Thiazole DerivativesCHINESE JOURNAL OF CHEMISTRY, Issue 4 2001Yong-Jun Liu Abstract On the basis of ZINDO program, we have designed a program to calculate the nonlinear second-order polarizability ,yk and ,, according to the SOS expression. The second-order nonlinear optical properties of 4-nitro-4,-dimethylamino-stilbene and a series of its thiazole derivatives were studied. The calculated results were that: When replacing a benzene ring in 4-nitro-4,-dimethylamino-stilbene by a thiazole ring, the influence on , values depends on the position of thiazole ring. When the thiazole ring connects with nitro group (acceptor), the , values increase significantly compared with corresponding stilbene derivatives. The , values of 2-(p -donor-,-styryl)-5-nitro-thiazole derivatives (2,7) are larger than those of 2-(p -nitro-,-styryl)-5-donor-thiazole derivatives (8,13) and 2-(p -donor-phenyl)-azo-5-nitro-thiazole derivatives (14,19). The 2-(p -donor-,-styryl)-5-nitro-thiazole derivatives (2,7) are good candidates as chromophores duo to their high nonlinearities and potential good thermal stability. [source] Synthesis and Molluscicidal Activity of Some 1,3,4-Triaryl-5-chloropyrazole (III), Pyrano[2,3-c]pyrazole (V), Pyrazolylphthalazine (VIII) and Pyrano[2,3-d]thiazole Derivatives (X).CHEMINFORM, Issue 39 2006Fathy M. Abdelrazek 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] Facile, alternative route to Lubeluzole, its enantiomer, and the racemateCHIRALITY, Issue 4 2006Claudio Bruno Abstract Lubeluzole [(S)- 9] has been synthesized by a convergent synthesis, alkylation of N -methyl- N -piperidin-4-yl-1,3-benzothiazol-2-amine (4) with (+)-(R)-1-chloro-3-(3,4-difluorophenoxy)propan-2-ol [(+)-(R)- 8] being the key step. Alcohol (+)-(R)- 8 was obtained from commercially available (R)-epichlorohydrin [(R)- 6], while the thiazole derivative 4 was easily obtained starting from N -protected piperidin-4-one (1) in a three-step procedure. The same method was used in order to obtain both the (R)-stereoisomer of lubeluzole [(R)- 9] and its racemate [(RS)- 9]. Overall yields ranged from 20% to 35%. The enantiomeric excess values for (S)- 9 and (R)- 9 were 97% and 94% respectively, as analyzed by chiral HPLC. Chirality, 2006. © 2006 Wiley-Liss, Inc. [source] Synthesis of 2,3-dihydro-1,3,4-thiadiazole, thiazole, and triazolo[4,3- a]pyrimidine derivatives from ethyl benzoylacetateHETEROATOM CHEMISTRY, Issue 2 2004Nora M. Rateb Thiophene and thiazole derivatives can be obtained from potassium salt of ethyl 3-oxo-3-phenyl-2-[(phenylamino)thioxomethyl]propanoate and ethyl chloroacetate in N,N -dimethylformamide solution under different conditions. 2,3-Dihydro-1,3,4-thiadiazoles and triazolo[4,3- a]pyrimidine were obtained from reaction of hydrazonoyl halides with each of thioanilide and pyrimidine-2-thione, respectively. Structures of the newly synthesized compounds were elucidated on the basis of elemental analysis, spectral data, and alternative synthesis route whenever possible. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:107,113, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10222 [source] Heterocyclic synthesis containing bridgehead nitrogen atom: Synthesis of 3-[(2H)-2-oxobenzo[b]pyran-3-yl]- s -triazolo[3,4- b]-1,3,4-thiadiazine and thiazole derivativesHETEROATOM CHEMISTRY, Issue 2 2003M. A. Raslan The reaction of 2H-2-oxobenzo[b]pyran-3-hydrazide (2) with carbon disulfide in basic DMF afforded potassium thiocarbamate 3, which readily underwent heterocyclization upon its reaction with hydrazine and/or phenacyl bromide to yield 1,2,4-tiazole (4) and thiazole 7 derivatives, respectively. Condensation of 4 with substituted phenacyl bromide and/or chloranil gave 1,2,4-triazole[3,4-b]thiadiazine (5a,b) and 3,10-bis-[2H-2-oxobenzo[b]pyran-3-yl]-6,13-dichloro-bis-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazino[5,,6,-b:5,,6,-e]cyclohexa-1,4-diene (6), respectively. Cyclization of thiosemicarbazide 10 by refluxing it in sodium hydroxide and/or phosphoryl chloride afforded triazole 13 and thiadiazole 15 derivatives, respectively. Also, 10 reacted with phenacyl bromide in the presence of anhydrous sodium acetate to give the oxothiazolidine derivative 17. The structure of the synthesized compounds were confirmed by elemental analyses, IR, 1H NMR, and mass spectra. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:114,120, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10109 [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] Theoretical Study on Second-order Nonlinear Optical Properties of Substituted Thiazole DerivativesCHINESE JOURNAL OF CHEMISTRY, Issue 4 2001Yong-Jun Liu Abstract On the basis of ZINDO program, we have designed a program to calculate the nonlinear second-order polarizability ,yk and ,, according to the SOS expression. The second-order nonlinear optical properties of 4-nitro-4,-dimethylamino-stilbene and a series of its thiazole derivatives were studied. The calculated results were that: When replacing a benzene ring in 4-nitro-4,-dimethylamino-stilbene by a thiazole ring, the influence on , values depends on the position of thiazole ring. When the thiazole ring connects with nitro group (acceptor), the , values increase significantly compared with corresponding stilbene derivatives. The , values of 2-(p -donor-,-styryl)-5-nitro-thiazole derivatives (2,7) are larger than those of 2-(p -nitro-,-styryl)-5-donor-thiazole derivatives (8,13) and 2-(p -donor-phenyl)-azo-5-nitro-thiazole derivatives (14,19). The 2-(p -donor-,-styryl)-5-nitro-thiazole derivatives (2,7) are good candidates as chromophores duo to their high nonlinearities and potential good thermal stability. [source] | ||||||||||