反应详情

tert-Butyl 2-(3-(bis(tert-butoxycarbonyl)amino)-6-(2-cyanoethanamido)pyrazin-2-yl)-6-methyl-1H-benzo[d]imidazole-1-carboxylate (isolated from Step 2) was dissolved in DCM (5 mL) and TFA (28.29 mg, 19.11 μL, 0.2481 mmol) was added. The reaction mixture was stirred at ambient temperature for 1 hour and then concentrated in vacuo. The residue was purified by reverse phase preparative HPLC [Waters Sunfire C18, 10 mM, 100 Å column, gradient 10%-95% B (solvent A: 0.05% TFA in water; solvent B: CH3CN) over 16 minutes at 25 mL/min]. The fractions were collected and freeze-dried to give the title compound as a yellow solid (8 mg, 10.5% Yield). 1H NMR (400.0 MHz, CDCl3) δ 2.4 (3H, s), 3.95 (2H, s), 7.15 (1H, d), 7.42-7.49 (1H, m), 7.52-7.58 (1H, m), 8.0 (1H, br s), 8.62 (1H, s), 10.55 (1H, s), 12.8 (1H, vbr s); MS (ES+) 308.0.

1. concentrationconcentrated in vacuo
2. customThe residue was purified by reverse phase preparative HPLC [Waters Sunfire C18, 10 mM, 100 Å column, gradient 10%-95% B (solvent A: 0.05% TFA in water; solvent B: CH3CN) over 16 minutes at 25 mL/min]
3. customThe fractions were collected
4. customfreeze-dried