N-Acetylsulfanilyl chloride

A mixture of 10.5 grams of 1-ethylcytosine, 18.6 grams of N-acetylsulfanilyl chloride, and 50 ml of pyridine is stirred at room temperature for 2 days. The precipitated solid is removed by filtration, and the filtrate is evaporated at 60°C under reduced pressure to a syrup. The syrup is triturated with 0.25 N hydrochloric acid, and the solid N-(N-acetyl-sulfanilyl)-1-ethylcytosine obtained is isolated and dried. This solid is suitable for use without further purification. 

Metyrapone Acetylsalicylic acid Caraspirin calcium Acetylsalicylic acid chloride Benoryiate Phenprocoumon N-Acetylsulfanilyl chloride Sulfacytine Sulfamethoxazaole 3-Acetylthiomethyl propanoic acid Captopril... 

R = COMe) with chlorosulfonic acid (five equivalents) at 60 °C (2 hours) to give A -acetylsulfanilyl ehloride (3 R = COMe). Treatment with ammonia and selective hydrolysis of the resultant acetylsulfanilamide afforded the product 4, (R = H). The chlorosulfonation of acetanilide is of eonsiderable industrial importance in the manufacture of sulfa drugs, consequently various modifications have been investigated to improve the yield of N -acetylsulfanilyl chloride (see Chapter 4, p 102). 

N -Heterocyclic Sulfanilamides. The parent sulfanilamide is manufactured by the reaction of A/-acetylsulfanilyl chloride with excess concentrated aqueous ammonia, and hydrolysis of the product. Most heterocycHc amines are less reactive, and the condensation with the sulfonyl chloride is usually done in anhydrous media in the presence of an acid-binding agent. Use of anhydrous conditions avoids hydrolytic destmction of the sulfonyl chloride. The solvent and acid-binding functions are commonly filled by pyridine, or by mixtures of pyridine and acetone. Tertiary amines, such as triethylamine, may be substituted for pyridine. The majority of A/ -heterocycHc sulfanilamides are made by simple condensation with A/-acetylsulfanilyl chloride and hydrolysis. 

Acetxilide-p-sulfonyl chloride Acetylsulfanilyl chloride N-Acelylsulfxilyl chloride N-Acetylsulphanilyl chloride ASC Benzenesulfonyl chloride, 4-(xe lamino)- Dagenan chloride EINECS 204-485-1 HSDB 2712 NSC 127860 Sulfanilyl chloride, N-acetyl-. Needles or prisms mp = 149° Xm = 259 nm (s = 17700, MeOH) soluble in CeHe, CHCI3, very soluble in EtOH, Et20. 

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