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) 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) was dissolved in 5 mL dichloromethane, mixed with 5 mL trifluoroacetic acid and stirred over night at RT. Then the mixture was concentrated in vacuo, and the remaining residue was purified by preparative HPLC, yielding 430 mg (72% of the theoretical) of the title compound as a colorless foam.

Provenance & Evidence