Trifluoroacetic acid → N,2-dimethylalanyl-N-[(3R,4S,5S)-3-methoxy-1-{(2S)-2-[(1R,2R)-1-methoxy-2-methyl-3-oxo-3-{[(1S)-2-phenyl-1-(1,3-thiazol-2-yl)ethyl]amino}propyl]pyrrolidin-1-yl}-5-methyl-1-oxoheptan-4-yl]-N-methyl-L-valinamide

Participants

Reaction Steps

To a mixture of #87 (58 mg, 0.068 mmol, 1 eq.) in dichloromethane (8 mL) was added trifluoroacetic acid (2 mL). After stirring overnight, the reaction mixture was concentrated in vacuo. The residue was taken up in ethyl acetate (10 mL), washed with saturated aqueous sodium bicarbonate solution, dried over sodium sulfate, filtered, and concentrated in vacuo to give #88 (52 mg, quantitative). LC-MS 757.6 [M+H+], retention time=0.69 minute; 1H NMR (400 MHz, DMSO-d6), presumed to be a mixture of rotamers, characteristic signals: δ [8.64 (br d, J=8.6 Hz) and 8.87 (br d, J=8.6 Hz), total 1H], 7.80-7.85 (m, 1H), [7.77 (d, J=3.3 Hz) and 7.80 (d, J=3.1 Hz), total 1H], [7.63 (d, J=3.1 Hz) and 7.66 (d, J=3.3 Hz), total 1H], 7.20-7.31 (m, 4H), 7.13-7.19 (m, 1H), [5.39 (ddd, J=11, 8.5, 4 Hz) and 5.49-5.56 (m), total 1H], [4.51 (dd, J=9, 8 Hz) and 4.61 (dd, J=9, 8 Hz), total 1H], 3.16, 3.20, 3.21 and 3.25 (4 s, total 6H), 2.94 and 3.03 (2 br s, total 3H), 2.10 and 2.10 (2 s, total 3H), 1.16 (br s, 3H), 1.04-1.12 (m, 6H), 0.72-0.80 (m, 3H).

Provenance & Evidence