Entrapment of Toxic Anions using Calixarenes Framework

Submit Manuscript | http://medcraveonline.com bind specifically to anions is an area of current importance [1-4]. There are numerous reasons to heighten up this interest. One of the open challenge for modern chemist in anion recognition chemistry is selective recognition of anions. In this course, many synthetic receptors have been developed owing to the coordination ability of the appended substituents. However, the development of anionic receptor is comparatively slow than cationic receptor due to the exceptional properties of anions [5]. These include, delocalised nature of negative charge over atoms, larger size, diverse geometry of anions (spherical, linear, tetrahedral or octahedral), pH dependence and salvation [6]. Release of anion through various commercial applications viz. nucleophiles, bases, catalysts, redox reagents can pose unwanted environmental toxicities [6]. Hence, entrapment of anions through receptors is pivotal that enables the separation using the coordination mechanism. Intriguingly, anions are also essential for the biological relevant metabolic functions therefore molecules that mimicks the anion binding are therapeutically pertinent for treating cystic fibrosis, cancer and Alzheimer’s diseases [7]. There is, therefore, intense effort being devoted to the problem of anion complexation and recognition using macro cyclic receptors based on calixarenes, cyclophane, steroid, pyrroles, and other charged and non-charged macro cyclic receptors are reported so far [810].