To a 4 mL vial was added (azidocarbonyl) dipiperidine (ADDP) (25.9 mg, 0.102 mmol) in anhydrous toluene. The vial was introduced into a dry box and tributylphosphine (41.5 mg, 3 eq, 0.205 mmol) was added to the vial. This mixture was shaken until the solution turned clear. To this solution was added a solution of 2-methoxyethanol in anhydrous tetrahydrofuran (1.2 equivalents, 0.082 mmol, 6.24 mg). This mixture was stirred for 10 minutes at ambient temperature. To this mixture was added a solution of Example 36e (0.068 mmol, 31.4 mg) in anhydrous toluene/anhydrous tetrahydrofuran (1:1 v/v) (1 mL). The reaction mixture was stirred at room temperature overnight in the dry box. The reaction mixture was concentrated to dryness and the residue purified by reverse phase HPLC (C18, 10-100% acetonitrile in 0.1% TFA/water) to provide the title compound (4.24%, 1.5 mg). 1H NMR (400 MHz, DMSO d6/D2O) δ ppm 7.49 (d, J=2.75 Hz, 1H), 7.38-7.43 (m, 1H), 7.37 (d, J=2.75 Hz, 1H), 7.35-7.36 (m, 1H), 7.34 (d, J=2.75 Hz, 1H), 7.22-7.27 (m, 1H), 7.05-7.11 (m, 1H), 6.87 (d, J=8.54 Hz, 1H), 6.30 (d, J=2.75 Hz, 1H), 3.78-3.81 (m, 2H), 3.57 (s, 3H), 3.37 (t, J=5.65 Hz, 2H), 3.20 (s, 3H), 3.16 (t, J=7.32 Hz, 2H), 1.26 (t, J=7.48 Hz, 3H). ESI+ m/z=518.0 (M+H)+.
