Originator
Migristene,Rhone Poulenc,France,1965
Manufacturing Process
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.