反应详情

A mixture of N-tert-butoxycarbonyl-1-methyl-D-tryptophyl-D-methionine ethyl ester (2.4 g), formic acid (25 ml), and saturated solution of hydrogen chloride in formic acid (10 ml) was stirred on an ice bath for 1.5 hours. After removal of the solvent, the crude residue was dissolved in ethanol (20 ml) and saturated ammonia in ethanol (10 ml) was added. The resulting mixture was stirred for 16 hours at room temperature and precipitated mass was collected, washed with ethanol, and dried. Recrystallization from ethanol gave (3R,6R)-3-(1-methylindol-3-ylmethyl)-6-(2-methylthioethyl)piperazine-2,5-dione (1.16 g).

1. customAfter removal of the solvent
2. dissolutionthe crude residue was dissolved in ethanol (20 ml)
3. additionsaturated ammonia in ethanol (10 ml) was added
4. stirringThe resulting mixture was stirred for 16 hours at room temperature
5. customprecipitated mass
6. customwas collected
7. washwashed with ethanol
8. customdried
9. customRecrystallization from ethanol