Trifluoroacetic acid → (5S,8S,11S,12R)-11-((S)-sec-butyl)-1-(9H-fluoren-9-yl)-5,8-diisopropyl-12-methoxy-4,10-dimethyl-3,6,9-trioxo-2-oxa-4,7,10-triazatetradecan-14-oic acid

Participants

Reaction Steps

650 mg (0.94 mmol) of 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 5 ml of dichloromethane, 5 ml of trifluoroacetic acid were added and the mixture was stirred at RT overnight. The mixture was then concentrated under reduced pressure, and the residue that remained was purified by preparative HPLC. This gave 430 mg (72% of theory) of the title compound as a colourless foam.

Provenance & Evidence