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1.
Egyptian Journal of Chemistry. 2009; 52 (3): 289-299
em Inglês | IMEMR | ID: emr-135684

RESUMO

The reaction of 3-cyanoacctylindole I with trichloroacetonitrile afforded trichloroll1cthylpropen-1-one derivative 3 which upon the reaction with an excess of trichloroacetonitrilc yielded the ditrichlorome-thylpyrimidine derivative 5. It was converted to a variety of pyrazolo 7, dihydrazino 9. and isoxazolo pyrimidine II derivatives. The enaminonitrile 2 was used as a substrate to form the pyridine 13, 14, 16, diazepine 20 and pyranone 22 as well as 1, 2, 4-triazolo-25. 1, 2, 3, 4-tetrazolo-27, and benzimidazolo-pyrimidine 29 derivatives


Assuntos
Piridinas/síntese química , Pirimidinas/síntese química , Benzodiazepinas/química , Pironas/síntese química
2.
Egyptian Journal of Chemistry. 2001; 44 (1-3): 33-50
em Inglês | IMEMR | ID: emr-56671

RESUMO

The rates of alkaline hydrolysis of methyl prop-2-enoic acid [methylacrylate] 1 and methyl-2-methyl-prop-2-enoic acid [methylmethacrylate] 2 were studied at temperatures ranging from 10 to 35 degree in two series of dioxane-water and acetone-water mixtures containing 10 to 75 percent by volume of the organic component. The rate constants were found to be higher in acetone-water mixtures and decreased with increasing the dielectric constant of the medium. The kinetic studies and application of the differential method show that the rate follows a second order kinetic equation, first order with respect to both ester and hydroxide ion and the reaction proceeds by a B[Ac2] mechanism. The distance of closest approach of solvent molecules to the activated complex b and the distance of closest approach of solvent molecules to the transition state G were computed


Assuntos
Cinética , Temperatura , Dioxanos , Solventes , Metilmetacrilatos/química , Ésteres
3.
Egyptian Journal of Chemistry. 1999; 42 (2): 175-187
em Inglês | IMEMR | ID: emr-107883

RESUMO

4-phenyl-3 thiosemicarbazide has been used in a new approach for the synthesis of heterocyclic and fused heterocyclic compounds which have many applications as anticancer, antimicrobial, antitubercular and antibacterial agents. In the present work, the reactivity of 4-phenyl-3-thiosemicarbazide towards diethylmalonate, malononitrile, urea and thiourea to afford pyrazole, triazole and pyrimidine derivatives was described. It is widely realized that certain fused heterocyclic compounds [1-4] posses diverse therapeutic potentialities; thus, they show antitumor, antimicrobial, antitubercular as well as antibacterial [5-8] activities. Prompted by these facts, the use of 4-phenyl-3-thiosemicarbazide for the preparation of new fused heterocycles belonging to pyrazoles, pyrazolo-triazoles and pyrimidines was suggested


Assuntos
Compostos Heterocíclicos , Pirazóis , Antibacterianos , Antineoplásicos
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