Shams H.Z.Mohareb R.M.Helal M.H.Mahmoud A.E.Department of ChemistryFaculty of ScienceHelwan UniversityAin HelwanCairoEgypt; Department of Organic ChemistryFaculty of PharmacyOctober University for Modern Sciences and ArtsOctober CityEgypt; Department of ChemistryFaculty of ScienceCairo UniversityGizaEgypt2020-01-252020-01-25201114203049https://doi.org/10.3390/molecules16010052PubMed ID 21187817https://t.ly/2dPm9ScopusThe reaction of 2-amino-3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophene with ethyl cyanoacetate gave 2-cyano-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2- yl)-acetamide. The latter was used to synthesize different heterocyclic derivatives comprising thiophene, thiazole, pyrazole, pyridine, pyrimidine, and coumarin rings. The mechanistic and synthetic pathways depended on regioselective attack and/or cyclization by the cyanoacetamido moiety in the key precursor on various chemical reagents. The competition of the reaction pathways including dipolar cyclization, dinucleophilic-bielectrophilic attack, ?-attack, Gewald-type attack, and condensation reactions led to the diversity of the synthesized products. The antitumor activities of the synthesized products were studied and evaluated. Most of the compounds revealed high inhibitory effects when screened in vitro for their antiproliferative activity. Three human cancer cell lines, namely, breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) were used in the screening tests. The simplicity of the synthetic procedures which mainly involved one-pot reactions under mild reaction conditions, the convenience of yield production and the diversity of the reactive sites in the produced systems play a valuable role for further heterocyclic transformations and further biological investigations. � 2010 by the authors.English4,5,6,7-tetrahydrobenzo[b]thiopheneAntitumorPyrazolePyridineThiazoleantineoplastic agentheterocyclic compoundthiophene derivativearticlechemistrycyclizationdrug screeninghumaninfrared spectroscopymass spectrometrynuclear magnetic resonance spectroscopysynthesistumor cell lineAntineoplastic AgentsCell Line, TumorCyclizationDrug Screening Assays, AntitumorHeterocyclic CompoundsHumansMagnetic Resonance SpectroscopyMass SpectrometrySpectroscopy, Fourier Transform InfraredThiophenesArticlehttps://doi.org/10.3390/molecules16010052PubMed ID 21187817