Hydrochloric Acid → ethyl (1R,2S)-1-{[(4S)-4-{[(4-bromophenyl)sulfonyl]oxy}-1-{(2S)-2-[(tert-butoxycarbonyl)amino]non-8-enoyl}-L-prolyl]amino}-2-ethenylcyclopropanecarboxylate

Participants

Reaction Conditions

Reaction Steps

HATU (27.3 g) was added to the solution of (2S)-2-[(tert-butoxycarbonyl)amino]non-8-enoic acid (19.5 g) in DMF (100 ml) and the solution was stirred 15 minutes. The reaction mixture was cooled to 0° C. Then, the amine from Step 3 (31.8 g) in DMF (200 ml) (cooled to 0° C.) was added followed by DIPEA (11.40 ml). The solution was stirred at 0° C. for 1 hour. Hydrochloric acid (1M) was added and the mixture was extracted with diethyl ether (3×). The combined organic fractions were washed with brine, dried over magnesium sulfate, filtered and concentrated. The residue was purified by flash chromatography (ISCO, 0 to 100% ethyl acetate in hexanes) to give the desired product (40.2 g) as a white foam. LRMS (ES+) m/z 762.2 (M+Na)+.

Provenance & Evidence