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The present book includes various methodologies for the synthesis of biologically significant heterocyclic compounds using several reusable heterogeneous catalysts such as aluminium nitride, nano-zinc oxide, lanthanum oxide, ytterbium triflate and montmorillonite-KSF clay under different conditions along with biological activity of some of the synthesized compounds. Chapter-1: Introduction. Chapter-2: Synthesis of 2, 4, 5-triaryl imidazoles, benzimidazoles and bis(indolyl)methanes. Chapter-3: Synthesis of 2, 3-dihydroquinazolin-4(1H)-ones -amino phosphonates. Chapter-4: Lanthanum oxide as a catalyst for the synthesis of Hantzsch polyhydroquinolines and ytterbium triflate as a catalyst for the synthesis of dicoumarols. Chapter-5: Nano ZnO as catalyst for synthesis of pyranopyrazoles and furanones. Chapter-6: Synthesis and biological screening of some novel hydrazone derivatives.

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Dr. Rajendra P. Pawar; [M.Sc., Ph.D., Post Doc.(Israel)], Head and Associate Professor; Department of Chemistry, Deogiri College, Aurangabad,(MS)India 431005. Dr. Sunil U. Tekale;[M.Sc., CSIR/UGC-NET, Ph.D.] Assistant Professor, Department of Chemistry, Shri Muktanand College, Gangapur Dist. Aurangabad (MS) India 431109

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