反应详情

9.1 g of the crude product N-[(9H-fluoren-9-ylmethoxy)carbonyl]-N-methyl-L-valyl-N-[(3R,4S,5S)-1-tert-butoxy-3-methoxy-5-methyl-1-oxoheptan-4-yl]-N-methyl-L-valinamide (Intermediate 3) were taken up in 56.6 ml of dichloromethane, 56.6 ml of trifluoroacetic acid were added, and the mixture was stirred at RT for 2 h. Subsequently, the reaction mixture was concentrated under reduced pressure and the remaining residue was purified by flash chromatography, using dichloromethane, 3:1 dichloromethane/ethyl acetate and 15:5:0.5 dichloromethane/ethyl acetate/methanol as eluent. After purification of the corresponding fractions and concentration, 5.8 g (86% of theory) of the title compound were obtained as a colourless foam.

1. concentrationSubsequently, the reaction mixture was concentrated under reduced pressure
2. customthe remaining residue was purified by flash chromatography
3. customAfter purification of the corresponding fractions and concentration, 5.8 g (86% of theory) of the title compound
4. customwere obtained as a colourless foam