الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
The thesis includes an introduction reviewing the chemistry of cyanoacetohydrazide and its use in the synthesis ofpyrazoles and con¬densed pyrazoles. A survey is done until 1993. The thesis describes the reaction of cyanoacetohydrazide, as a key starting material, with different aldehydes to give the correspond¬ing hydrazones, which subsequently cyclized via reactions between the nucleophilic and electrophilic centers to afford pyrazolo [1, 2 - a] py-razoles (9a - c) , chromeno [4,3 - c] pyrazolo [1,2 - a] pyrazoles (5a,b). The hydrazone (7c), obtained from cyanoacetohydrazide and o-nitrobenzaldehyde, when refluxed in acetic acid gave the pyrazolo [1,2 - a] pyrazole (9c), which when refluxed in acetic acid in presence of zinc dust gave a product ^identified as pyrazolo /7 \2 V 1,2] pyrazo¬lo [4,3 - c] quinoline. Similarly, hydrazones (lla,b), derived from condensation reac¬tion between cyanoacetohydrazide and ketones, when refluxed in acet¬ic acid underwent self-cyclization via the electrophilic and nucleophil¬ic centers giving the corresponding chromenopyrazolone structure 15. In accordance with this view, when cc - cyanoacetylacetone (lib) was heated in acetic acid, the 3- aminopyrazolone was obtained.