Afloqualone HCl

Originator

Arofuto ,TANABES EIYAKU ,Japan ,1983

Manufacturing Process

14.4 g (0.053 mol) of N-(2-amino-5-nitrobenzoyl)-o-toluidine and 6.3 g (0.08 mol) of pyridine are dissolved in 300 ml of tetrahydrofuran. 12.2 g (0.126 mol) of fluoroacetyl chloride are added to the solution for 10 minutes under ice-cooling. The solution is stirred at the same temperature for 30 minutes and then at room temperature for 2.5 hours. The reaction solution is allowed to stand at room temperature overnight. The crystalline precipitate is collected by filtration, washed with water and then dried. 16.4 g of N-(2- fluoroacetamido-5-nitrobenzoyl)-o-toluidine are obtained. Yield: 93.7%; MP 238-239°C.
16.5 g (0.05 mol) of N-(2-fluoroacetamido-5-nitrobenzoyl)-o-toluidine and 25.5 g (0.25 mol) of acetic acid anhydride are dissolved in 250 ml of glacial acetic acid. The solution is refluxed for 2 hours under heating. Then, the reaction solution is evaporated to remove solvent. The residue thus obtained is poured into ice-water, and the aqueous mixture is adjusted to pH 9 with potassium carbonate. The crystalline precipitate is collected by filtration. 15.5 g of 2-fluoromethyl-3-(o-tolyl)-6-nitro-4(3H)-quinazolinone are obtained. Yield: 98.7%; MP 155-158°C (recrystallized from ethanol).
A mixture of 2.0 g (0.064 mol) of 2-fluoromethyl-3-(o-tolyl)-6-nitro-4(3H)- quinazolinone, 0.2 g of 5% palladium-carbon and 100 ml of acetic acid is shaken for 30 minutes in hydrogen gas. The initial pressure of hydrogen gas is adjusted to 46 lb and the mixture is heated with an infrared lamp during the reaction. After 30 minutes of this reaction, the pressure of hydrogen gas decreases to 6 lb. After the mixture is cooled, the mixture is filtered to remove the catalyst. The filtrate is evaporated to remove acetic acid, and the residue is dissolved in chloroform. The chloroform solution is washed with 5% aqueous sodium hydroxide and water, successively. Then, the solution is dried and evaporated to remove solvent. The oily residue thus obtained is dissolved in 2 ml of chloroform, and the chloroform solution is passed through a column of 200 g of silica gel. The silica gel column is eluted with ethyl acetatebenzene (1:1). Then, the eluate is evaporated to remove solvent. The crude crystal obtained is washed with isopropyl ether and recrystallized from isopropanol. 0.95 g of 2-fluoromethyl-3-(o-tolyl)-6-amino-4(3H)-quinazolinone is obtained. Yield: 52.5%; MP 195-196°C.

Therapeutic Function

Muscle relaxant

Raw materials

Preparation Products