Triethylamine (10.21 mg, 14.06 μL, 0.1009 mmol) was added to a solution of tert-butyl N-tert-butoxycarbonyl-N-[5-(4-ethylsulfonylpiperazin-1-yl)-3-ethynyl-pyrazin-2-yl]carbamate (50 mg, 0.1009 mmol) and N-hydroxybenzimidoyl chloride (15.70 mg, 0.1009 mmol) in THF (4 mL) and the reaction mixture allowed to stir at ambient temperature for 1 hour. After this time the reaction mixture was heated under reflux for 3 hours and allowed to cool to RT. The reaction was treated with HCl in dioxane (126.1 μL of 4 M, 0.5045 mmol), allowed to stir overnight at ambient temperature, concentrated in vacuo and the resultant residue was purified by reverse phase preparative HPLC [Waters Sunfire C18, 10 uM, 100A 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 an orange solid (9.9 mg, 18% Yield). 1H NMR (DMSO) d 1.03 (3H, t), 2.90 (2H, q), 3.11 (4H, m), 3.33 (4H, m), 5.88 (2H, br s), 7.34-7.36 (4H, m), 7.77 (2H, m), 7.92 (1H, s) ppm; MS (ES+) 414.98
