Trifluoroacetic acid → HCID 18343042, compound

Participants

Reaction Steps

Intermediate 63 was prepared as described above for the preparation of intermediate 52. From 962 mg of N-(Boc)-L-Tyrosine methyl ester and 720 mg of Intermediate 10D was prepared 1.32 g of BOC-protected intermediate methyl ester (81% yield; 1H NMR (CDCl3, 300 MHz) δ8.07-8.03 (m, 2H), 7.19-7.13 (m, 2H), 7.08 (d, 2H, J=8.4), 6.97 (d, 2H, J=8.4), 4.99-4.97 (m, 3H), 4.58-4.57 (m, 1H), 3.74 (s, 3H), 3.09-3.03 (m, 2H), 2.82 (q, 2H. J=7.5), 1.59 (s, 9H), 1.30 (t, 3H, J=7.5); From 1.31 g of BOC-protected ester intermediate was prepared the crude TFA salt of intermediate 63. The TFA salt was suspended into water and the pH adjusted to ˜7.0 with 10% NaOH. The resulting solids were filtered and dried to yield 1.01 g of the title compound; 1H NMR (DMSO-d6, 300 MHz) δ8.01-7.97 (m, 2H), 7.36 (t, 2H, J=9.0), 7.18 (d, 2H, J=8.4), 6.96 (d, 2H, J=8.4), 4.97 (s, 2H), 3.53-3.51 (m, 2H), 3.09-3.04 (m, 2H), 2.84 (q, 2H, J=7.5), 1.22 (t, 3H, J=7.5); low resolution MS (ES+)m/e 384.87 (MH+); TLC Rf=0.44 (4/1, DCM/MeOH).

Provenance & Evidence