反应详情

500 mg (1 mmol) 1-ethyl-3-methyl-2-((E)-2-phenylamino-vinyl)-5-sulfo-3-(3-sulfo-propyl)-3H-indolium sodium salt 2 and 387 mg (1 mmol) 3-(3-carboxypropyl) -2,3-dimethyl-1-ethyl-3H-indolium iodide 3 salt were dissolved in a mixture of 10 ml acetic acid and 10 ml acetic anhydride. Subsequently, 5 ml pyridine was added. The solution was stirred under reflux for 15 minutes. After cooling to room temperature (about 20° C. to about 22° C.), 20 ml ether was added. The precipitate that was obtained, which was a mixture of the diastereomers 4.1 and 4.2, was extracted by suction, washed with ether, and dried. The residue was purified by column chromatography: RP-18: methanol/water 1/1.

1. temperatureunder reflux for 15 minutes
2. additionwas added
3. customThe precipitate that was obtained
4. additiona mixture of the diastereomers 4.1 and 4.2
5. extractionwas extracted by suction
6. washwashed with ether
7. customdried
8. customThe residue was purified by column chromatography