PREPARATIONS 181 Sulphanilamide (/>-Aminobenzenesulphonamide). NH 2-C 6 H 4-SO 2 NH 2 . Sulphanilamide, the simplest member of a large series of bacteriostatic drugs, can readily be prepared by the following reactions. Acetanilide, when treated with an excess of chlorosulphonic acid, gives />-acetamidobenzenesulphonyl chloride (Reaction A), which readily reacts with ammonia to give />-acetamido-benzenesulphonamide (Reaction B). The acctamido-group in the latter CH 3 CO-NHC 6 H 5-f HOSO 2 Cl = CH 3 CO NH C^H 4-SO 1 Cl + H,O (A) CH 8 CO-NH C 4 H 4-SO 2 Cl -f- 2NH 8 = CH 1 CO-NH-0,H 4-SO 1 NH 1-f- NH 4 Cl (B) CH 8 CO-NH-C 6 H 4 SO 8 NH 8-^H 1 O = NH 3-C 8 H 4-SO 8 NH, -f CH 8 COOH (C) compound can be readily hydrolysed under conditions which leave the sulphon-amido group unaffected, and Sulphanilamide can thus be obtained (Reaction C). Note that p-acetamidobenzenesulphonyl chloride \\ill similarly react with primary and secondary amines, and the products, after hydrolysis of the acetyJ group, may furnish notable drugs:
This is the end of the preview. Sign up
access the rest of the document.