10-[2-(dimethylamino)propyl]-N,N-dimethyl-10H-phenothiazine-2-sulphonamide monomethanesulphonate

Migristene,Rhone Poulenc,France,1965

ChEBI: Dimethothiazine mesylate is a member of phenothiazines, a sulfonamide and a methanesulfonate salt.

A solution of 3-dimethylsulfamoylphenthiazine (10 grams) in xylene (100 cc) is heated under reflux for 3 hours with sodium amide (1.5 grams). A solution of 1-dimethylamino-2-chloropropane (4.4 grams) in anhydrous xylene (30 cc) is then added and heating under reflux continued for 4 hours. After cooling the suspension obtained is agitated with water (50 cc) and ether (30 cc). The aqueous layer is separated and the basic products are extracted from the organic phase with 10% hydrochloric acid. The xylene layer is discarded and, after the combined acid solutions have been made alkaline with sodium carbonate, the base is extracted with chloroform. The chloroform solutions are then washed with water and dried over anhydrous potassium carbonate. After evaporation of the solvent under reduced pressure there is obtained a crude resinous base (9.7 grams).
On the addition of ethereal hydrogen chloride to a solution of the base in isopropanol and recrystallization from anhydrous ethanol of the salt formed, there is obtained 3-dimethylsulfamoyl-10-(2-dimethylaminopropyl) phenthiazine hydrochloride (2.1 grams), MP 214°C with decomposition. After dissolving the product in anhydrous ethanol and adding methanesulfonic acid there is obtained fonazine mesylate.