反应详情

4.50 g of the N-(2-ethoxycarbonyloxy-4-methoxybenzoyl)cysteamine was dissolved in 70 ml of methanol, and 17 ml of 2N aqueous solution of sodium hydroxide was added to the solution. The mixture was agitated for 45 minutes. The solvent was distilled off in evacuated atomosphere, and 2N aqueous solution of sodium hydroxide and methylene chloride were added to the mixture for separation. The aqueous phase was further washed with methylene chloride, acidified by adding 6N aqueous hydrochloric acid, and extracted with methylene chloride. The mixture was dried over anhydrous sodium sulfate, and the solvent was distilled off in evacuated atomosphere. The residue was subjected to column chromatography using silica gel, and there was obtained 2.63 g of N-(2-hydroxy-4-methoxybenzoyl)cysteamine (I).

1. distillationThe solvent was distilled off in evacuated atomosphere, and 2N aqueous solution of sodium hydroxide and methylene chloride
2. additionwere added to the mixture for separation
3. washThe aqueous phase was further washed with methylene chloride
4. additionby adding 6N aqueous hydrochloric acid
5. extractionextracted with methylene chloride
6. dry with materialThe mixture was dried over anhydrous sodium sulfate
7. distillationthe solvent was distilled off in evacuated atomosphere