Benzofuran moiety is the main component of many biologically active natural and synthetic heteroc... more Benzofuran moiety is the main component of many biologically active natural and synthetic heterocycles.
Electrochemical fluorination of 2-quinolyl and 4-(7-trifluoromethyl)quinolyl sulfides bearing an ... more Electrochemical fluorination of 2-quinolyl and 4-(7-trifluoromethyl)quinolyl sulfides bearing an electron-withdrawing group at the position alpha to the sulfur atom was studied. Fluorination was successfully carried out using Et(4)NF.nHF (n = 3, 4) and Et(3)N.3HF as a supporting electrolyte and a fluoride ion source in dimethoxyethane in a divided cell to provide the corresponding alpha-fluorinated sulfides in good yields. A trifluoromethyl group positioned on the quinoline ring significantly enhanced anodic alpha-fluorination. 4-(Methylthio)-7-(trifluoromethyl)quinoline was also found to undergo anodic fluorination efficiently. Solvent effects of various donor numbers were also established.
Afinidad Revista De Quimica Teorica Y Aplicada, 2011
2-Cyano-N-(pyridin-4-yl)acetamide (2) was prepared andthen treated with hydrazonoyl chlorides 3 t... more 2-Cyano-N-(pyridin-4-yl)acetamide (2) was prepared andthen treated with hydrazonoyl chlorides 3 to afford the corresponding aminopyrazoles 5. Heating a mixture of 2 with benzylidenemalononitriles and with ethyl benzylidenecyanoacetates afforded the corresponding bipyridines 10 and 16, respectively. Treatment of 2 with phenylisothiocyanatein DMF/KOH followed by addition of the appropriate hydrazonoyl chlorides 5, 10 and ethyl chloroacetate gave the corresponding 1,2,4-thiadiazoles 22 and 27 and 1,3-thiazole 24, respectively.
Treatment of 2-(2-bromoacetyl)-3 H-benzo[ f]chromen-3-one with pyridine, quinoline, and 2-methylq... more Treatment of 2-(2-bromoacetyl)-3 H-benzo[ f]chromen-3-one with pyridine, quinoline, and 2-methylquinoline afforded the corresponding pyridinium, quinolinium and 2-methylquinolinium bromides. The latter salts underwent [3 + 2] 1,3-dipolar cycloaddition with some electron deficient acetylene and ethylene derivatives to give the corresponding indolizine and pyrrolo[1,2- a]quinoline derivatives. Moreover, 2-(2-bromoacetyl)-3 H-benzo[ f]chromen-3-one reacted with arylidene cyanothioacetamides to afford the corresponding 2-amino-4,5-dihydrothiophene-3-carbonitriles. The synthesised compounds were characterised based on their elemental analysis and spectral data. Antimicrobial activity of some of the synthesised compounds was evaluated.
The pyridinium bromides 2a,b reacted with dimethyl acetylene- dicarboxylate (DMAD) to give the in... more The pyridinium bromides 2a,b reacted with dimethyl acetylene- dicarboxylate (DMAD) to give the indolizine derivatives 6a,b. Bromide salts 2a,b reacted also with β-nitrostyrene, ethyl acrylate and with acrylamide to give the corresponding indolizine derivatives 8a,b and 10a-d. Reaction of the quinolinium salts 12a,b with DMAD, β-nitrostyrene and with ethyl acrylate as dipolarophiles furnished the corresponding pyrrolo[1,2-a]quinoline derivatives 16a,b, 18a,b and 20a,b, respectively. Bromide salts 2b and 22 underwent intramolecular cyclization via elimination of water and hydrogen bromide molecules when heated at reflux condition to give the angularly fused indolizine and pyrrolo[1,2-a]quinoline structures 21 and 23, respectively.
A facile and convenient synthesis of a series of 1,2,4-triazolo[5,1-c][1,2,4]triazine, 1,3,4-thia... more A facile and convenient synthesis of a series of 1,2,4-triazolo[5,1-c][1,2,4]triazine, 1,3,4-thiadiazole, thiazolidine, and pyrido[1,2-a]pyrimidine derivatives incorporating pyridine moiety via the versatile, readily accessible 2-cyano-N-(pyrid-2-yl)acetamide are described.
... Kamal M. Dawood,* Ahmad M. Farag and Eman A. Ragab Department of Chemistry, Faculty of Scienc... more ... Kamal M. Dawood,* Ahmad M. Farag and Eman A. Ragab Department of Chemistry, Faculty of Science, Cairo University, Giza 12613, Egypt ... n cm-1 3371, 3248 (NH, NH2), 2230 (CºN); 1H NMR (DMSO-d6) d 5.14 (br, s, 2H, NH2, D2O-ex-changable), 5.81 (s, 1H, CH), 7.37-7.47 ...
Tetrahedron Vol. 49, No. 13, O. 27612766, 1993 00404020 93 S6.O.00 Printed in Great Britain Pagam... more Tetrahedron Vol. 49, No. 13, O. 27612766, 1993 00404020 93 S6.O.00 Printed in Great Britain Pagamort Pray Ltd Facile Syntheses of Bi1,2,4triazoles via Hydrazonyl Halides Ahmad S. Shawali*, Ahmad M. Farag, Hassan A. Albar and Kamal M. Dawood Department of ...
Phosphorus, Sulfur, and Silicon and the Related Elements, 2010
... FACILE SYNTHESIS OF THIOPHENE-AND 1,3,4-THIADIAZOLE-BASED HETEROCYCLES Kamal M. Dawood, Eman ... more ... FACILE SYNTHESIS OF THIOPHENE-AND 1,3,4-THIADIAZOLE-BASED HETEROCYCLES Kamal M. Dawood, Eman A. Ragab, and Ahmad M. Farag Department of Chemistry, Faculty of Science, Cairo University, Giza, Egypt ... AA Fadda, E. Abdel-Latif, and RE El-Mekawy, Eur. ...
Benzofuran moiety is the main component of many biologically active natural and synthetic heteroc... more Benzofuran moiety is the main component of many biologically active natural and synthetic heterocycles.
Electrochemical fluorination of 2-quinolyl and 4-(7-trifluoromethyl)quinolyl sulfides bearing an ... more Electrochemical fluorination of 2-quinolyl and 4-(7-trifluoromethyl)quinolyl sulfides bearing an electron-withdrawing group at the position alpha to the sulfur atom was studied. Fluorination was successfully carried out using Et(4)NF.nHF (n = 3, 4) and Et(3)N.3HF as a supporting electrolyte and a fluoride ion source in dimethoxyethane in a divided cell to provide the corresponding alpha-fluorinated sulfides in good yields. A trifluoromethyl group positioned on the quinoline ring significantly enhanced anodic alpha-fluorination. 4-(Methylthio)-7-(trifluoromethyl)quinoline was also found to undergo anodic fluorination efficiently. Solvent effects of various donor numbers were also established.
Afinidad Revista De Quimica Teorica Y Aplicada, 2011
2-Cyano-N-(pyridin-4-yl)acetamide (2) was prepared andthen treated with hydrazonoyl chlorides 3 t... more 2-Cyano-N-(pyridin-4-yl)acetamide (2) was prepared andthen treated with hydrazonoyl chlorides 3 to afford the corresponding aminopyrazoles 5. Heating a mixture of 2 with benzylidenemalononitriles and with ethyl benzylidenecyanoacetates afforded the corresponding bipyridines 10 and 16, respectively. Treatment of 2 with phenylisothiocyanatein DMF/KOH followed by addition of the appropriate hydrazonoyl chlorides 5, 10 and ethyl chloroacetate gave the corresponding 1,2,4-thiadiazoles 22 and 27 and 1,3-thiazole 24, respectively.
Treatment of 2-(2-bromoacetyl)-3 H-benzo[ f]chromen-3-one with pyridine, quinoline, and 2-methylq... more Treatment of 2-(2-bromoacetyl)-3 H-benzo[ f]chromen-3-one with pyridine, quinoline, and 2-methylquinoline afforded the corresponding pyridinium, quinolinium and 2-methylquinolinium bromides. The latter salts underwent [3 + 2] 1,3-dipolar cycloaddition with some electron deficient acetylene and ethylene derivatives to give the corresponding indolizine and pyrrolo[1,2- a]quinoline derivatives. Moreover, 2-(2-bromoacetyl)-3 H-benzo[ f]chromen-3-one reacted with arylidene cyanothioacetamides to afford the corresponding 2-amino-4,5-dihydrothiophene-3-carbonitriles. The synthesised compounds were characterised based on their elemental analysis and spectral data. Antimicrobial activity of some of the synthesised compounds was evaluated.
The pyridinium bromides 2a,b reacted with dimethyl acetylene- dicarboxylate (DMAD) to give the in... more The pyridinium bromides 2a,b reacted with dimethyl acetylene- dicarboxylate (DMAD) to give the indolizine derivatives 6a,b. Bromide salts 2a,b reacted also with β-nitrostyrene, ethyl acrylate and with acrylamide to give the corresponding indolizine derivatives 8a,b and 10a-d. Reaction of the quinolinium salts 12a,b with DMAD, β-nitrostyrene and with ethyl acrylate as dipolarophiles furnished the corresponding pyrrolo[1,2-a]quinoline derivatives 16a,b, 18a,b and 20a,b, respectively. Bromide salts 2b and 22 underwent intramolecular cyclization via elimination of water and hydrogen bromide molecules when heated at reflux condition to give the angularly fused indolizine and pyrrolo[1,2-a]quinoline structures 21 and 23, respectively.
A facile and convenient synthesis of a series of 1,2,4-triazolo[5,1-c][1,2,4]triazine, 1,3,4-thia... more A facile and convenient synthesis of a series of 1,2,4-triazolo[5,1-c][1,2,4]triazine, 1,3,4-thiadiazole, thiazolidine, and pyrido[1,2-a]pyrimidine derivatives incorporating pyridine moiety via the versatile, readily accessible 2-cyano-N-(pyrid-2-yl)acetamide are described.
... Kamal M. Dawood,* Ahmad M. Farag and Eman A. Ragab Department of Chemistry, Faculty of Scienc... more ... Kamal M. Dawood,* Ahmad M. Farag and Eman A. Ragab Department of Chemistry, Faculty of Science, Cairo University, Giza 12613, Egypt ... n cm-1 3371, 3248 (NH, NH2), 2230 (CºN); 1H NMR (DMSO-d6) d 5.14 (br, s, 2H, NH2, D2O-ex-changable), 5.81 (s, 1H, CH), 7.37-7.47 ...
Tetrahedron Vol. 49, No. 13, O. 27612766, 1993 00404020 93 S6.O.00 Printed in Great Britain Pagam... more Tetrahedron Vol. 49, No. 13, O. 27612766, 1993 00404020 93 S6.O.00 Printed in Great Britain Pagamort Pray Ltd Facile Syntheses of Bi1,2,4triazoles via Hydrazonyl Halides Ahmad S. Shawali*, Ahmad M. Farag, Hassan A. Albar and Kamal M. Dawood Department of ...
Phosphorus, Sulfur, and Silicon and the Related Elements, 2010
... FACILE SYNTHESIS OF THIOPHENE-AND 1,3,4-THIADIAZOLE-BASED HETEROCYCLES Kamal M. Dawood, Eman ... more ... FACILE SYNTHESIS OF THIOPHENE-AND 1,3,4-THIADIAZOLE-BASED HETEROCYCLES Kamal M. Dawood, Eman A. Ragab, and Ahmad M. Farag Department of Chemistry, Faculty of Science, Cairo University, Giza, Egypt ... AA Fadda, E. Abdel-Latif, and RE El-Mekawy, Eur. ...
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