www.derpharmachemica.com t Available online a Scholars Research Library Der Pharma Chemica, 2014, 6(4):147-152 (http://derpharmachemica.com/archive.html) ISSN 0975-413X CODEN (USA): PCHHAX 147 www.scholarsresearchlibrary.com Synthesis, antimicrobial and antifungal screening of novel chalcones containing imidazo[1,2-a] pyridine nucleus R. Saddik 1 , A. Gaadaoui 2 , M. Koudad 1 , A. Ousaid 1 , A. Elaatiaoui 1 , A. Hamal 2 , A. Zarrouk 1 and N. Benchat 1 1 LCAE-URAC18, Faculté des Sciences, Université Mohammed Premier, Oujda, Morocco 2 Laboatoire de génitique & Biotechnologie (LGB), Faculté des Sciences, Université Mohammed Premier, Oujda, Morocco _____________________________________________________________________________________________ ABSTRACT A series of chalcones were prepared by reacting various 2-(phenyl) imidazo [1,2-a] pyridine-3-carbaldehyde with acetophenones in the presence of alcoholic alkali. The structure elucidation of synthesized compounds has been done on the basis of elemental analysis, infrared and 1H nuclear magnetic resonance spectroscopy and further supported by Mass spectrometry. All the compounds have been evaluated for their in vitro biological assay like antibacterial activity towards Gram positive and Gram negative bacterial strains and antifungal activity towards Aspergillus niger at a concentration of 40µg/ml. The biological activities of synthesized compounds were compared with standard drugs. Keywords: Imidazo [1, 2-a] pyridine; Imidazo [1,2-a]pyridine-3-carbaldehyde chalcones; antifungal activity; antibacterial activity. _____________________________________________________________________________________________ INTRODUCTION Synthesis of new compound with appropriate therapeutic importance is a major challenge in medicinal chemistry. Recently, imidazo [1,2-a] pyridines have significant importance in the pharmaceutical industry[1] owing to their various interesting biological activity displayed over a broad range of therapeutic classes; these molecules exhibit antiviral [2], anti-inflammatory [3], analgesic, antipyretic, antiulcer, and antibacterial[4] properties. They are also β- amyloid formation inhibitors, GABA and benzodiazepine receptor agonists [5]and cardiotonic agents [6]. Drug formulations containing imidazo [1,2-a]pyridine that are currently available on the market include Alpidem (anxiolytic)[7], Zolpidem (hypnotic)[8]and olprinone (PDE-3 inhibitor)[9]. The non-benzodiazepines are generally used as sedatives, anticonvulsants, hypnotics, anxiolytics and muscle relaxants as they show less adverse effects compared to classical benzodiazepines [10]. In fact, imidazopyridines are the major class of non-benzodiazepines, acting upon various central nervous systems (CNS) disorders. Several imidazo [1,2-a]pyridine nucleus already in market which include Alpidem has sedative and anxiolytic properties and Zolpidem is a hypnotic drug. Both Alpidem and Zolpidem have higher affinity for benzodiazepine-1 than for benzodiazepine-2 receptors and their interaction with various receptors has been reported [11]. Some imidazo [1,2- a] pyridine containing drugs are as follow: