Definition

ChEBI: 7-Sulfamoyl-1,2,4-benzothiadiazine 1,1-dioxide in which the hydrogen at position 6 is substituted by chlorine and that at position 3 is substituted by a benzylsulfanylmethyl group. A diuretic, it is used to treat hypertension and edema.

Manufacturing Process

The preparation of the dihydro analog is as follows: (A) Preparation of 3-Chloromethyl-6-Chloro-7-Sulfamyl-3,4-DihydroBenzothiadizine-1,1-Dioxide - To 8 ml of 40-50% chloroacetaldehyde aqueous solution and 7 ml of dimethylformamide are added 10 grams of 2,4- disulfamyl-5-chloroaniline. The mixture is heated on a steam bath for 2 hours after which it is concentrated at reduced pressure. The residue is triturated with water. The solid material is recrystallized from methanol-ether after treatment with activated carbon to give 7.2 grams of product, MP 229°- 230°C. (B) Preparation of Benzylthiomethyl-6-Chloro-7-Sulfamyl-3,4- Dihydrobenzothiadiazine-1,1-Dioxide - A mixture of 3-(chloromethyl)-6-chloro- 7-sulfamyl-3,4-dihydrobenzothiadiazine-1,1-dioxide (0.02 mol) and benzylmercaptan (0.024 mol) in 20 ml of 10% sodium hydroxide and 20 ml of dimethylformamide is stirred at room temperature for 6 hours. After heating for 10 minutes on a steam bath, the mixture is cooled and acidified with 6 N HCl. The product, after recrystallization from acetone, melts at 210°-211°C.

Brand name

Aquatag (Solvay Pharmaceuticals); Fovane (Pfizer).

Safety Profile

Poison by intravenous route. Adiuretic and antihypertensive agent. When heated todecomposition it emits very toxic fumes of SOx, NOx, andCl-.