Studies with Biologically Active Enaminones: an Easy Method for Structural Elucidation of Products Produced from Enaminone Starting Materials through Pathways Employing Microwave Irradiation
Saleh M. Al-Mousawi *
Department of Chemistry, Faculty of Science, Kuwait University, P.O. Box 5969, Safat, 13060 – Kuwait
Morsy A. El-Apasery
Department of Chemistry, Faculty of Science, Kuwait University, P.O. Box 5969, Safat, 13060 – Kuwait and Dyeing, Printing and Textile Auxiliaries Department, Textile Research Division, National Research Centre, 12622 Dokki, Giza, Egypt
Huda Mahmoud
Department of Biological Sciences, Faculty of Science, Kuwait University, P.O. Box 5969, Safat, 13060 – Kuwait
Mohamed H. Elnagdi
Department of Chemistry, Faculty of Science, Kuwait University, P.O. Box 5969, Safat, 13060 – Kuwait
*Author to whom correspondence should be addressed.
Abstract
Reactions of enaminones 3a-f with malononitrile under microwave irradiation conditions were found to afford cyano-substituted aminodienamides 8a-f, whose structures were elucidated using both X-Ray crystallographic analysis and NOE methods. In addition, cyclization of 8e to form pyridone 10 takes place upon treatment with a mixture of acetic acid and hydrochloric acid. Coupling enaminone 3e with benzenediazonium chloride affords hydrazone 12, which reacts with cyanoacetamide to produce pyridazinone 17. Finally, the biological activity of the prepared compounds against gram positive bacteria, gram negative bacteria and yeast were evaluated.
Keywords: Dienamides, X-ray crystal structure determination, microwave irradiation, pyridines, NOE difference experiment, pyridazines