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Abstract his thesis describes the studying synthesis of new phthalazine derivatives through the reaction of nucleophiles a with the key intermediates with the aim to evaluate their biological activities. 1. Preparation of the key intermediate phthalazinone derivative 3(a,b): The reaction of phthalic anhydride 1 with benzene or chlorobenzene in the presence of anhydrous AlCl3 were carried out under reflux condition at 80 °C to produce aroyl benzoic acid derivatives 2(a,b). Further cyclisation with hydrazine hydrate to give corresponding intermediate 3(a,b), the key intermediate phthalazine derivatives 4(a,b) was synthesized by chlorination of 3(a,b) through dehydroxychlorinated by POCl3 in a heating mixture of DMF and acetonitrile Scheme 1 2. Synthesis of amino phthalazine derivatives 5,6(a-c). Reactions of phthalazine derivatives 4(a,b) with nitrogen containing nucleophiles such as aniline, m-methyl aniline and p-chloro aniline in dry chloroform affording 5,6(a-c). 3. Synthesis of 1-oxo-Arylphthalazine sulphonylchloride 7(a,b), and sulphonylhydrazide 8(a,b). Arylphthalazine derivatives 3(a,b) were added portion wise to chlorosulphonic acid in the presence of excess amount of thionylchloride at 0 oC with stirring , the temperature was elevated to 90 oC for 72 hours , the reaction mixture was poured into crushed ice , the products were filtered off to give 7(a,b), an treatment with hydrazine hydrate in THF at room temperature affording 8(a,b) in good yields. 4. Synthesis of 1-oxophthalazine sulphonylhydrazone derivatives 9, 10(a-d) and 11, 12(a-c). A mixture of phthalazine sulfonylhydrazide 8(a,b) and aldehyde derivatives such as benzaldehyde, p-chlorobenzaldehyde, anisaldehyde, and mbromobenzaldehyde or sugar derivatives such as D-glucose, D-arabinose and Dxylose in ethanol with catalytic amount of glacial acetic acid were reflux for 2 hours followed reaction affording 9,10(a-d) and 11,12(a-c) in good yields. 5. Synthesis of 1-oxophthalazine carboxamide and carbothioamide derivatives 13, 14(a,b). A mixture of compound 3(a,b) and phenylisocyanate or phenylisothiocyanate in benzene was refluxed for 8 hours , follow reaction to give 13,14(a,b). 6. Reaction with pipredine under Mannich condition 15(a,b). A mixture of compound 3(a,b) and pipredine and formaldehyde solution and DROP of HCl in ethanol was refluxed for 4 hours , followed reaction affording 15(a,b). The structures of all synthesized compounds were characterized by various spectral techniques. (C.f. EX. part) Biological activity All synthesized compounds witch tested against C. Pipiens larval proved to a promising controlling against C. Pipiens larval. |