Available online www.jocpr.com Journal of Chemical and Pharmaceutical Research, 2016, 8(11):204-210 Research Article ISSN : 0975-7384 CODEN(USA) : JCPRC5 204 Chlorosulfonation of Acetanilide to Obtain an Intermediate for the Preparation of a Sulfa Drug P Shashikala 1 and D Shruthi Keerthi 2* 1 University College of Technology, Osmania University, Hyderabad, Telangana, India 2 Department of Chemical Engineering, Anurag Group of Institutions, Ghatkesar, Telangana, India __________________________________________________________________________________ ABSTRACT Sulphonamides were the first effective chemotherapeutic agents employed systematically for the prevention and cure of bacterial infections in humans. They are called as wonder drugs of their times. Though their usage has been limited they are still being used for burns, bacterial infections in stomach. In the present work the yield of sulfathiazole was increased by using new modified method based on the available literature from which high yields with reduced time periods were successfully achieved. Sulfathiazole is prepared by Chlorosulfonation of Acetanilide to obtain an intermediate which is reacted with 2-aminothiazole. The samples of intermediate and 2- aminothiazole with ratios (3:1, 1:1, and 1:3) and with different acid acceptors named Pyridine, Sodium bi- carbonate, Di-methyl aniline and Ammonium hydroxide are studied. The analysis was done by using IR spectroscopy in FT – IR which is found to be the best method for identification of samples. Keywords: Acetanilide; Chlorsulfonation; FT–IR Spectroscopy; P-Acetamidobenzenesulfonylchloride; Pyridine; Sulfathiazole __________________________________________________________________________________ INTRODUCTION Sulfonamides were the first effective chemotherapeutic agents employed systematically for the prevention and cure of bacterial infections in humans. They were classified as the first real “wonder” drug developed [1]. After the introduction of penicillin and other antibiotics, the popularity of sulfonamides decreased. However, they are still considered useful in certain therapeutic fields, especially in the case of ophthalmic infections as well as infections in the urinary and gastrointestinal tract. Sulfathiazole, (4-Amino-N-2-thiazolylbenzensulfonamide), is clinically one of the most used. Sulfonamide is the basis of several groups of drugs. They are bacterio-static antibiotics that competitively inhibit conversion of p-amino benzoic acid to dihydropteroate, which bacteria need for folate synthesis and ultimately purine and DNA synthesis. For preparation of sulfathiazole [2-5] many methods are available in present day trend but many of the processes don’t offer maximum efficiency. The main aim of the work is to develop a method which gives maximum yields with reduced time and cost efficient when compared to literature. These processes were divided into 3 steps for proper understanding where first step is chlorosulfonation [3] of acetanilide which results in an intermediate p-acetamidobenzenesulfonylchloride. In the present investigation it was found that proper mixture of acetanilide and chlorosulfonic acid is required for a good quality of intermediate. So a trial run was made at different temperatures up till 114 o C till the best sample is obtained. Figure 1: Structure of Sulfathiazole