反应详情

To a solution of the crude product (19.6 g) containing N,N-dimethyl-L-valinamide hydrochloride obtained in B) and triethylamine (44.0 g) in ethanol (150 mL) was added 4-thioxothiazolidin-2-one (14.4 g) at room temperature, and the reaction mixture was stirred at room temperature for 3 hr. The solvent was evaporated under reduced pressure, the obtained solid was suspended in THF, and the suspension was filtered through celite pad and silica gel pad. The filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (NH, ethyl acetate/petroleum ether) to give the title compound (4.2 g).

1. customThe solvent was evaporated under reduced pressure
2. filtrationthe suspension was filtered through celite pad and silica gel pad
3. concentrationThe filtrate was concentrated under reduced pressure
4. customthe residue was purified by silica gel column chromatography (NH, ethyl acetate/petroleum ether)