Reaction Steps
A mixture of ethyl (2S)-2-(tert-butoxy)-2-{11-cyclopropyl-16-fluoro-4,25-dimethyl-24-oxa-1,5,7,8,11-pentaazapentacyclo[23.2.2.16,9.02,7.013,18]triaconta-2,4,6(30),8,13(18),14,16-heptaen-3-yl}acetate (35 mg, 0.054 mmol) and NaOH (2.154 mg, 0.054 mmol) in EtOH (3 mL) was refluxed for 2 h. It was then cooled to rt and purified by preparative HPLC to isolate (2S)-2-(tert-butoxy)-2-{11-cyclopropyl-16-fluoro-4,25-dimethyl-24-oxa-1,5,7,8,11-pentaazapentacyclo[23.2.2.16,9.02,7.013,18]triaconta-2,4,6(30),8,13(18),14,16-heptaen-3-yl}acetic acid (25.2 mg, 0.040 mmol, 73.7% yield) as a white solid. 1H NMR (500 MHz, DMSO-d6) δ 7.18 (t, J=7.2 Hz, 1H), 6.98 (d, J=9.9 Hz, 1H), 6.85 (t, J=7.7 Hz, 1H), 6.43 (s, 1H), 5.75 (s, 1H), 4.39 (t, J=11.9 Hz, 1H), 3.89 (d, J=9.9 Hz, 1H), 3.65-3.54 (m, 2H), 3.30 (d, J=15.0 Hz, 2H), 3.17 (s, 2H), 2.87-2.77 (m, 1H), 2.73-2.63 (m, 2H), 2.51-2.45 (m, 4H), 1.89-1.42 (m, 11H), 1.16 (br. s., 12H), 0.33 (br. s., 1H), 0.24 (br. s., 1H), 0.13 (br. s., 1H), −0.06 (br. s., 1H). LCMS (M+1)=622.3.
