الفهرس | Only 14 pages are availabe for public view |
Abstract SUMMARY 2(3H)-Furanones represent an important type of five-membered heterocyclic systems. The importance of these compounds stems from facile opening of the lactone ring with both nucleophilic and electrophilic reagents to give acyclic product. These acyclic products are the precursors of a wide variety of synthetically and biologically important heterocyclic systems e.g. pyridazinones, oxadiazoles, triazoles, isothiazolones…etc. In this investigation, ring transformation of pyrazolyl substituted 2(3H)-furanone into novel fused and unfused nitrogen containing heterocycles, and the behavior of the synthesized compounds against highly pathogenic avian influenza H5N1 are studied. The original work of this thesis consists of three main parts: Part 1: In this part, the acid hydrazide (1) was obtained from hydrazinolysis of 2(3H)-furanone bearing pyrazolyl moiety at position-3. The reactions of the acid hydrazide (1) with different carbonyl compounds were studied. Thus, when reacted with acetylacetone, ethyl acetoacetate or ethyl cinnamate gave the pyrazole derivatives (4), (6) or (8) respectively. On the other hand, the reaction with acetonylacetone led to the formation of the pyrridazine derivative (2). The pyrazoldione derivative (9) was obtained via refluxing (1) with diethyl malonate in ethanol. Summary II The phthalazinedione derivative (10) was obtained upon treatment the acid hydrazide with phthalic anhydride. The open-chain Shciff base products (12) and (14) were obtained upon condensation of the acid hydrazide with benzil and panisaldehyde respectively. Reaction of the Schiff base product (13) with thioglycolic acid gave the thiazolidinone product (14) The chemical transformations in this part can be represented by the two Schemes (A) and (B). |