反应详情

L-Alanyl-L-proline (1.0 g, 5.4 mmol) is dissolved in a mixture of 10.8 ml of 0.5 N potassium hydroxide and 750 mg (5.4 mmol) of anhydrous potassium carbonate, and 10 ml of acetonitrile are added. After cooling in an ice bath, a concentrated acetonitrile solution of 1.2 g of 6-chloronicotinoyl chloride is added dropwise while stirring and keeping the pH of the mixture at 12 to 13 with 1N potassium hydroxide, as necessary. Stirring is continued for 2 additional hours at room temperature, then the solution is neutralized to pH 6 with aqueous hydrochloric acid, and the solvent is distilled off under reduced pressure. The residue thus obtained is suspended in 50 ml of absolute ethanol, the remaining potassium chloride is separated by centrifugation, and the solvent of the clear solution is distilled off under reduced pressure. The crude product is purified through silica gel column chromatography, using absolute ethanol as eluant, to isolate 700 mg of the desired product (yield: 40%).

1. additionare added
2. temperatureAfter cooling in an ice bath
3. stirringStirring
4. customis continued for 2 additional hours at room temperature
5. distillationthe solvent is distilled off under reduced pressure
6. customThe residue thus obtained
7. customthe remaining potassium chloride is separated by centrifugation
8. distillationthe solvent of the clear solution is distilled off under reduced pressure
9. customThe crude product is purified through silica gel column chromatography