title: Synthesis of Some Novel Heterocyclic and Schiff Base Derivatives as Antimicrobial Agents.
abstract: Treatment of 2,3-diaryloxirane-2,3-dicarbonitriles 1a-c with different nitrogen nucleophiles, e.g., hydrazine, methyl hydrazine, phenyl hydrazine, hydroxylamine, thiosemicarbazide, and/or 2-amino-5-phenyl-1,3,4-thiadiazole, afforded pyrazole, isoxazole, pyrrolotriazine, imidazolothiadiazole derivatives 2-5, respectively. Reacting pyrazoles 2a-c with aromatic aldehydes and/or methyl glycinate produced Schiff's bases 7a-d and pyrazolo[3,4-b]-pyrazinone derivative 8, respectively. Treating 7 with ammonium acetate and/or hydrazine hydrate, furnished the imidazolopyrazole and pyrazolotriazine derivatives 9 and 10, respectively. Reaction of 8 with chloroacetic acid and/or diethyl malonate gave tricyclic compound 11 and triketone 12, respectively. On the other hand, compound 1 was reacted with active methylene precursors, e.g., acetylacetone and/or cyclopentanone producing adducts 14a,b which upon fusion with ammonium acetate furnished the 3-pyridone derivatives 15a,b, respectively. Some of newly synthesized compounds were screened for activity against bacterial and fungal strains and most of the newly synthesized compounds showed high antimicrobial activities. The structures of the new compounds were elucidated using IR, ¹H-NMR, (13)C-NMR and mass spectroscopy.
authors.affiliation: Department of Chemistry, Faculty of Science, University of Ain Shams, Cairo 11566, Egypt. meazabali2015@yahoo.com.
authors.forename: Mohamed E
authors.initials: ME
authors.lastname: Azab
authors.affiliation: Department of Chemistry, Faculty of Science, University of Ain Shams, Cairo 11566, Egypt. samehrizk2006@gmail.com.
authors.forename: Sameh A
authors.initials: SA
authors.lastname: Rizk
authors.affiliation: Pharmaceutical Chemistry Department, Drug Exploration & Development Chair (DEDC), College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia. aeamr1963@yahoo.com.|Applied Organic Chemistry Department, National Research Center, Dokki, Cairo 12622, Egypt. aeamr1963@yahoo.com.
authors.forename: Abd El-Galil E
authors.initials: Ael-G
authors.lastname: Amr
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D000935:Antifungal Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D066244:Proton Magnetic Resonance Spectroscopy; D012545:Schiff Bases / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D006571:Heterocyclic Compounds; D012545:Schiff Bases
keywords: Schiff bases; antimicrobial activities; isoxazole; oxirane; pyrazole; pyrazolopyrazine; pyridones