International Journal of Pharmacy and Pharmaceutical Sciences ISSN- 0975-1491 Vol 9, Issue 8, 2017 Review Article MESOIONIC SYDNONE: A REVIEW IN THEIR CHEMICAL AND BIOLOGICAL PROPERTIES ABDUALRAHMAN MOHAMMED ABDUALKADER1*, MUHAMMAD TAHER2, NIK IDRIS NIK YUSOFF1 1Pharmaceutical Chemistry Department, 2Pharmaceutical Technology Department, Faculty of Pharmacy, International Islamic University Malaysia, Kuantan, Pahang, Malaysia Email:
[email protected] Received: 08 Mar 2017 Revised and Accepted: 19 Jun 2017 ABSTRACT Various literature sources have documented sydnones as important molecules with exclusive chemical properties and a wide spectrum of bioactivities. Sydnone can be defined as a five-membered pseudo-aromatic heterocyclic molecule. Classically, 1,2,3-oxadiazole forms the main skeleton of sydnone. The molecule has delocalized balanced positive and negative charges. The five annular atoms share the positive charge and the enolate-like exocyclic oxygen atom bears the negative charge. The hydrogen atom at the position C4 was proved to have acidic and nucleophilic functionalities making the sydnone ring reactive towards electrophilic reagents. These unique chemical features enable sydnones to interact with biomolecules resulting in important therapeutic effects like anticancer, antidiabetic, antimicrobial, antioxidant and anti-inflammatory. Consequently, we aim from the current article to review the available chemical and pharmacological information on sydnone and its derivatives. Keywords: Sydnone, Mesoionic, Heterocycles, Anticancer, Antimicrobial, Anti-inflammatory © 2017 The Authors. Published by Innovare Academic Sciences Pvt Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) DOI: http://dx.doi.org/10.22159/ijpps.2017v9i8.18774 INTRODUCTION sydnone into the starting N-nitroso compound. These two facts indicate that the bicyclic system proposed by Earl is improbable [9].