A solution of [2-Chloro-4-(3-{2-[(E)-3,5-diamino-6-chloro-pyrazine-2-carbonylimino]-1,3,8-triaza-spiro[4.5]dec-8-yl}-3-oxo-propyl)-phenoxy]-acetic acid (step 2) (4.82 g, 8.52 mmol) in DMF (70 ml) was treated with 2-chloro-N,N-dipropyl-acetamide (3.18 g, 17.9 mmol) followed by sodium hydrogen carbonate (2.26 g, 26.9 mmol) and the resulting suspension heated to 60° C. overnight. Water (500 ml) was added to the reaction mixture and the product extracted with EtOAc (1000 ml). The organic extracts were washed with water (500 ml) and brine (500 ml), dried (MgSO4) and concentrated in vacuo. Purification by chromatography on silica eluting with 0-12% 2N ammonia in ethanol in DCM followed by further purification by C18 reverse phase chromatography eluting with MeCN/water afforded the title product; 1H NMR (400 MHz, DMSO-d6) δ 8.43 (1H, br s), 8.36 (1H, br s), 7.34 (1H, d), 7.14 (1H, dd), 7.02 (1H, s), 6.71 (2H, br s), 4.95 (2H, s), 4.89 (2H, s), 3.67-3.53 (2H, m), 3.39 (3H, br s), 3.19 (2H, t), 3.13 (2H, t), 2.75 (2H, t), 2.62 (2H, t), 1.65-1.41 (8H, m), 0.85 (3H, t), 0.80 (3H, t). LC-MS Rt 4.11 mins; 706.5 [M+H]+, Method 10minLC_v003.
