A solution of example 1C (7.41 g, 17.55 mmol), N,N-diethyl-1,3-propanediamine (3.32 ml, 21.06 mmol), 1-hydroxybenzotriazole hydrate (2.96 g, 19.31 mmol) and N-methylmorpholine (4.82 ml, 43.9 mmol) in N,N-dimethylformamide (88 ml) at room temperature was treated with 1-ethyl-3-[3-(dimethylamino)propyl]-carbodiimide hydrochloride (6.06 g, 31.6 mmol). The mixture was added to a well stirred solution of water (800 ml) and ethyl acetate (150 ml) using methanol to rinse the syringe and filter. The resulting suspension was stirred under a stream of nitrogen for several minutes to remove some of the methanol, and filtered with water and diethyl ether rinses to give, after drying, the title compound. 1H NMR (300 MHz, DMSO-d6) δ ppm 0.96 (t, J=7.14 Hz, 6H), 1.61-1.73 (m, 2H), 2.40-2.47 (m, 4H), 3.23-3.38 (m, 4H), 5.89 (bs, 2H), 6.80 (td, J=8.33, 2.78, 1H), 7.14 (bd, J=9.12, 1H), 7.27-7.34 (m, 1H), 7.37 (d, J=8 Hz, 2H), 7.47 (s, 1H) 7.51 (dt, J=11.92, 2.38 Hz, 1H), 7.60 (d, J=8 Hz, 2H), 8.45-8.53 (m, 2H) 8.94 (s, 1H) 8.98 (s, 1H). MS (ESI(+)) m/e 535.2 (M+H)+.
