%0 Journal Article %T The Reaction of Cyclopentanone with Cyanomethylene Reagents: Novel Synthesis of Pyrazole, Thiophene, and Pyridazine Derivatives %A Wagnat W. Wardakhan %A Eman M. Samir %J Journal of Chemistry %D 2013 %I Hindawi Publishing Corporation %R 10.1155/2013/427158 %X The reaction of cyclopentanone with either malononitrile or ethyl cyanoacetate gave the corresponding condensated products. The latter underwent some heterocyclic reactions to give new pyrazole, thiophene, and pyridazine derivatives. The antitumor evaluation of the newly synthesized products against the three cancer cells, namely, breast adenocarcinoma (MCF-7), nonsmall cell lung cancer (NCI-H460), and CNS cancer (SF-268) showed that some of them have high inhibitory effect towards three cell lines which is higher than the standard. 1. Introduction Heterocyclic compounds are worthy of attention for many reasons, chief among which are their biological activities, with many important drugs bearing thiazol, thiophene and pyridine derivatives. Therefore, organic chemists have been making extensive efforts to produce heterocyclic compounds by developing new and efficient synthetic transformations [1¨C10]. Many pyrazoles, thiophenes, and thiazoles were reported with a wide spectrum of biological activities which are known; they possess potent analgesic [11, 12], anticonvulsant, anti-inflammatory and antibacterial [13, 14], antipyretics [15], antitumor [16, 17], antiparasitic [18], antimicrobial [19], antihistaminic (H1) [20], antianxiety test in mice [21], antiarrhythmic [22], and serotonin antagonist [23]. In the present work, we studied the reaction of cyclopentanone with cyanomethylene reagents followed by heterocyclization of the products together with studying the antitumor evaluation of the newly synthesized products. 2. Experimental Melting points were determined on an Electrothermal melting point apparatus (Electrothermal 9100) and are uncorrected. IR spectra were recorded for KBr discs on a Pye Unicam SP-1000 spectrophotometer. 1H NMR spectra were measured on a Varian EM-390 at 200£¿MHz in DMSO- as solvent using TMS as internal standard. The mass spectra were recorded with Hewlett Packard 5988 A GC/MS system and GCMS-QP 1000 Ex Shimadzu instruments. Analytical data were obtained from the Microanalytical Data Unit at Cairo University, Giza, Egypt. Antitumor evaluation for the newly synthesized products was performed by a research group at the National Research Center and the National Cancer Institute at Cairo University. Fetal bovine serum (FBS) and l-glutamine were from Gibco Invitrogen Co. (Scotland, UK). RPMI-1640 medium was from Cambrex (New Jersey, NJ, USA). Dimethyl sulfoxide (DMSO), doxorubicin, penicillin, streptomycin, and sulforhodamine B (SRB) were from Sigma Chemical Co. (Saint Louis, MO, USA). Stock solutions of all compounds were prepared %U http://www.hindawi.com/journals/jchem/2013/427158/