反应详情

5-(3-Methanesulfonyloxy-propyl)-3-methyl-1H-pyrrole-2,4-dicarboxylic acid 2-tert-butyl ester 4-ethyl ester 1 g (11.964 g, 25.7 mmol) obtained from step 6 of Example 1 was dissolved in N,N-dimethylethylenediamine (12 ml, 97 mmol), the resulting solution was stirred for 5 hours at room temperature. After thin lay chromatography showed the disappearance of starting materials, the reaction mixture was added with ethyl acetate (80 ml) and saturated brine (80 ml), stirred for 5 minutes, and separated into layers. The organic phase was washed with saturated brine (80 ml×4) to remove N,N-dimethylethylenediamine, dried over anhydrous magnesium sulfate, filtered to remove the drying agent and concentrated under reduced pressure to obtain brown oil. The residue was purified by silica gel column chromatography to obtain the title compound 5-[3-(2-dimethylamino-ethylamino)-propyl]-3-methyl-1H-pyrrole-2,4-dicarboxylic acid 2-tert-butyl ester 4-ethyl ester 23a (5.85 g, yield 45.9%) as a yellow oil.

1. stirringstirred for 5 minutes
2. customseparated into layers
3. washThe organic phase was washed with saturated brine (80 ml×4)
4. customto remove N,N-dimethylethylenediamine
5. dry with materialdried over anhydrous magnesium sulfate
6. filtrationfiltered
7. customto remove the drying agent
8. concentrationconcentrated under reduced pressure
9. customto obtain brown oil
10. customThe residue was purified by silica gel column chromatography