Ammonia → HCID 69885766, compound

Participants

Reaction Steps

950 mg of (E)-3-(10-methoxymethyl-10H-pyrazino[2,3-b][1,4]benzothiazin-8-yl)propenoic acid was dissolved in a solvent mixture of tetrahydrofuran (10 ml) with N,N-dimethylformamide (10 ml) in a nitrogen atmosphere. Under ice-cooling, 0.48 ml of diethyl chlorophosphonate was dropped into the reaction mixture. After stirring at room temperature for 30 minutes, ammonia gas was blown into the system. Then the reaction mixture was distributed into an aqueous solution of sodium carbonate and ethyl acetate and extracted with ethyl acetate. The extract was washed with water and dried over anhydrous sodium sulfate. After distilling off the solvent under reduced pressure, the crystals thus precipitated were recrystallized from diisopropyl ether/ethyl acetate to thereby give 400 mg of the title compound as yellow crystals.

Provenance & Evidence