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Studies on the Synthesis and Cyclization Reactions of2-(5-Amino-3-arylpyrazol-1-yl)-3-methylquinoxalines

 

作者: Hassan A. El-Sherief,  

 

期刊: Journal of Chemical Research, Synopses  (RSC Available online 1997)
卷期: Volume 0, issue 9  

页码: 322-323

 

ISSN:0308-2342

 

年代: 1997

 

DOI:10.1039/a603951k

 

出版商: RSC

 

数据来源: RSC

 

摘要:

N N Me N N N N H R¢ R N N Me N N O N H Ph N N Me N N NH R R R¢ N N Me N N NH2 R N N Me NHNH2 1 3 5 2 8 N N Me N N R 7 S HN O R¢ R¢CHO RCOCl AcOH HCHO R¢–HN2 HSCH2CO2H RCOCH2CN N N Me N N NHSO2R C6H4Me- p 4 N N Me N N N R 6 R¢ RSO2Cl EtOH Ph C6H4Br- p C6H4Cl- p C6H4Me- p 2 R a b c d e H Me Et CH2Cl Ph 3 R Ph C6H4Me- p 4 R a b c d a b c d Ph C6H4Br- p C6H4Cl- p C6H4Me- p 5-7 R C6H4Cl- p Ph C6H4OMe- p C6H4Cl- p R¢ a b a b c d e Ph Ph Ph C6H4Br- p C6H4Br- p 8 R Me Ph C6H4Me- p Ph C6H4NO2- p R¢ RCO2H R¢CHO 322 J.CHEM. RESEARCH (S), 1997 J. Chem. Research (S), 1997, 322–323 J. Chem. Research (M), 1997, 2049–2061 Studies on the Synthesis and Cyclization Reactions of 2-(5-Amino-3-arylpyrazol-1-yl)-3-methylquinoxalines Hassan A. El-Sherief,* Abdalla M. Mahmoud and Ahmed A. Ismaiel Chemistry Department, Faculty of Science, Assiut University, Assiut, 71516, Egypt A series of 2-(5-amino-3-arylpyrazol-1-yl)-3-methylquinoxalines (2a–d) has been synthesized by the condensation of 2-hydrazino-3-methylquinoxaline (1) with substituted benzoylacetonitriles and converted into the corresponding 3,4-diaryl-1-(3-methylquinoxalin-2-yl)-4,8-dihydro-1H-pyrazolo[3,4-e][1,4]thiazepin-7(6H)-ones (7a–d) and 2-(3-aryl- 4,5,6,7-tetrahydro-5-alkyl/aryl-1H-pyrazolo[3,4-d]pyrimidin-1-yl)-3-methylquinoxalines (8a–e).Quinoxaline derivatives have been found to be biologically active compounds having antibacterial, antifungal, anticancer, antiinflammatory, antidepressant, anthelmintic and herbicidal properties.1–3 Likewise, pyrazole derivatives are reported to have antibacterial, antifungal and other biological activity.4–7 In view of the above interest in these compounds and in continuation of our studies on the cyclization of hydrazino heterocyclic compounds we have investigated 2-hydrazino-3-methylquinoxaline in ring-closure reactions with substituted benzoylacetonitrile under different reaction conditions.Condensation of 2-hydrazino-3-methylquinoxaline (1) with substituted benzoylacetonitriles either in boiling ethanol or by fusion led to the formation of 2-(5-amino-3-arylpyrazol- 1-yl)-3-methylquinoxalines (2) (Scheme).Condensation of the 3-phenylpyrazolyl derivative 2a with formic, acetic or propionic acid afforded the corresponding N-acyl derivatives 3a–c. Compounds 3b,d,e were also obtained on treatment of 2a with acetyl, chloroacetyl and benzoyl chloride11 respectively. Refluxing of the p-tolyl derivative 2d with arenesulfonyl chlorides12 in chloroform containing anhydrous K2CO3 provided the corresponding N-arylsulfonyl derivatives 4a,b.Condensation of 2 with aromatic aldehydes either in acetic acid or in toluene gave 2-(4-arylmethylidene - 5-imino-3-arylpyrazol-1-yl)-3-methylquinoxalines (5a–d), while in ethanol containing a few drops of piperidine, as a catalyst, the corresponding Schiff’s bases (6a–d) were the sole isolable products.15 Condensation of 5 with sulfanylacetic acid in boiling toluene gave 3,4-diaryl-1-(3-methylquinoxalin-2-yl)-4,8- dihydro-1H-pyrazolo[3,4-e][1,4]thiazepin-7(6H)-ones (7a–d).Interestingly, condensation of 6 with sulfanylacetic acid under the same reaction condition gave the same products 7. We also investigated the behaviour of 2 as a bifunctional nucleophile with formaldehyde and appropriate amines in order to study the reactivity at the 4- and 5-positions of the pyrazole moiety. When 2a,b were treated with formaldehyde and primary amines in boiling ethanol only one pure product *To receive any correspondence (e-mail: assiut@frcu.eun.eg). SchemeJ.CHEM. RESEARCH (S), 1997 323 8 was obtained. This could be formed via a double Mannich reaction.17 Techniques used: Elemental analysis, IR, 1H NMR, mass spectrometry, TLC References: 17 Schemes: 3 Tables: 3 (Yields, mps, spectral and analytical data for 2–8) Received, 5th June 1996; Accepted, 2nd June 1997 Paper E/6/03951K References cited in this synopsis 1 Y.Kurasawa and A. Takad, Heterocycles, 1986, 24, 2321. 2 Y. Kurasawa, M. Muramatsu, K. Yamazaki, S. Tajima, Y. Okamoto and A. Takada, J. Heterocycl. Chem., 1986, 23, 1379, 1391. 3 G. Skata, K. Makino and Y. Kurasawa, Heterocycles, 1988, 27, 2481. 4 G. Vertuani, P. Giori, M. Guarneri and G. P. Sarto, J. Pharm. Sci., 1985, 74, 1013. 5 P. Giori, T. Poli, C. B. Vicentini, M. Manfrini, M. Guarneri and V. Brandolini, Farmaco, Ed. Sci., 1985, 40, 795. 6 C. B. Vincentini, T. Poli, M. Manfrini, M. Guarnerim, P. Giori and V. Brandolini, Farmaco, Ed. Sci., 1987, 42, 133. 7 C. B. Vicentini, T. Poli, A. C. Veronese, V. Brandolini, M. Manfrini, M. Guarneri and P. Giori, Pestic. Sci., 1989, 27, 77. 11 C. B. Vicentini, A. C. Veronese, P. Giori, B. Lumachi and M. Guarneri, Tetrahedron, 1990, 46, 5777. 12 G. Szilagyi and P. Dvortsak, Monatsh. Chem., 1989, 120, 131. 15 L. Jennig, J. Hofmann, M. Alva-Astudillo and G. Mann, J. Prakt. Chem., 1990,l 332, 351. 17 M. Tramontini and L. Angiolini, Tetrahedron, 1990, 46, 1791.

 



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