%0 Journal Article
%T Green Chemical Synthesis and Analgesic Activity of Fluorinated Thiazolidinone, Pyrazolidinone, and Dioxanedione Derivatives
%A Harshita Sachdeva
%A Diksha Dwivedi
%A Pradeep Goyal
%J Organic Chemistry International
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/976032
%X Facile lemon juice catalyzed green and efficient synthesis of a series of new classes of 5-(fluorinatedbenzylidene)-2-thioxo-1,3-thiazolidin-4-ones (3a¨Ce), 5-methyl-4-(fluorinatedbenzylidene)-2-phenylpyrazolidin-3-ones (5a¨Ce), and 2,2-dimethyl-5-(fluorinatedbenzylidene)-1,3-dioxane-4,6-diones (7a¨Ce) by the reaction of fluorinated aromatic aldehydes with active methylene compounds is reported. Lemon juice is natural acid catalyst which is readily available, cheap, nontoxic, and ecofriendly. This method is experimentally simple, clean, high yielding, green, and with reduced reaction times. The product is purified by simple filtration followed by washing with water and drying process. Some of the synthesized compounds have been evaluated ¡°in vivo¡± for their analgesic activity and all the synthesized compounds are characterized by IR, 1H NMR, 13C NMR, 19F NMR, and mass spectral studies. 1. Introduction The steady growth of interest in the synthesis of heterocyclic compounds is connected with their raised biological activity and also with the fact that these compounds make possible the development of novel materials of unique properties. Pyrazolone is a biologically important scaffold associated with multiple pharmacological activities such as antimicrobial [1], anti-inflammatory [2], analgesic [3], antidepressant [4], anticonvulsant [5], antidiabetic [6], antihyperlipidemic [7], antiviral [8], antitubercular [9], antioxidant [10], and anticancer activites [11, 12]. The synthesis of pyrazolone and its derivatives has engrossed substantial attention from organic and medicinal chemists for many years as they belong to a class of compounds with proven utility in medicinal chemistry. One very interesting and promising class of heterocycles is the 4-thiazolidinone ring system. It represents a class of chemical products with interesting pharmacological and biological activities [13¨C18] including antidiabetic, antitubercular, anti-HIV, antiparasitic, hypnotic, and anathematic agents. Furthermore, the reactivity of the Meldrum¡¯s acid (2,2-dimethyl-1,3-dioxan-4,6-dione) as a methylene active compound was explored about 40 years after its preparation, when the structure was correctly attributed by Davidson and Bernhard [19] assigning the acidic proton to the central carbon, and its high acidity is still object of study [20]. It is known that the Meldrum¡¯s acid undergoes standard Knoevenagel condensation with aromatic and heteroaromatic aldehydes furnishing the corresponding arylidene derivatives, which are versatile substrates for different kinds of reactions [21,
%U http://www.hindawi.com/journals/oci/2013/976032/