(1.0 mmol), and aryl aldehyde (1.0 mmol) was conducted Furthermore, Aryl aldehydes with electron-withdrawing and electron-donating groups, under typical reaction conditions, also yielded good to excellent output of the products. As for the aryl aldehyde, nature was very important. When the aldehyde derivatives, especially with electron-withdrawing groups such as halide, were deployed, a larger output was obtained accordingly ( Scheme 35). Nawwar et al. 47 reported the isolation of the pyrrolopyridazinone 100 from the reaction of cyanoacetohydrazide 1 with cinnamoylacetonitrile oxime 99. The formation of this product is assumed to proceed via a Michael type addition by the active methylene to the activated oximino double bond giving the 1:1 Michael adduct which then cyclized to the final product 100 (Scheme 36) . The reaction of 1 with ethyl βphenyl -β-methylmethylene cyanoacetate 101 occured with the formation of 3-methyl -3-phenyl -4-cyanopyrazolin -5-one 102 which was formed via ylidene exchange with elimination of ethyl cyanoacetate and subsequent cyclization to the final isolable product 102 (Scheme 37) . Seven membered ring with two hetero atoms could be obtained from the reaction of cyanoacetohydrazide 1 with the unsaturated 1,3-diketone 105. The reaction is assumed to proceed via the intermediacy of 106, resulting from the Knoevenagel condensation which then undergoes intra-cyclization to give the 1, 2diazepinone 107 50 (Scheme 39). We also conclude that the reaction of compound 112 with 2cyanoacetohydrazide 1 supplied the corresponding cyanopyridazone derivative 113, which was treated with phosphorus oxychloride to give the corresponding chloro derivative 114. The latter compound was cyclized with hydrazine hydrate 3 to produce the amino pyrazole derivative 115, Scheme 41 53 . and 2-cyanoacetohydrazide 1 as described in literature 56,57 . When compound 116 was boiled with 2cyanoacetohydrazide 1 afforded 1,2-diazepine derivatives 117a, 117b, as shown in Scheme 42 58 . . Luckily, the reaction of the acid chloride 124 with 2-cyanoacetohydrazide 1 was predominantly capatalizing on the reaction conditions. Therefore, conducting the reaction at ambient temperature furnished the hydrazide derivative 125. Moreover, while at refluxing conditions, the pyrazolone derivative 126 was produced. It was also noted that, the iminochromene derivative 127 was obtained through treating the nitrile derivative 125 with salicylaldehyde 120 in the presence of a catalytic amount of piperidine (Scheme 44) .