A mixture comprising 4-(4-fluorophenyl)-2-isopropyl-2,7-diazaspiro[4.5]decan-1-one (ASW MedChem) (243 mg, 0.744 mmol), (R)-2-(2-(tert-butoxycarbonylamino)-2-methylpropanamido)-3-(1-methyl-1H-indol-3-yl)propanoic acid (Intermediate 3D) (300 mg, 0.744 mmol) and DIPEA (0.519 ml, 2.97 mmol) in acetonitrile (3 ml) was treated with ®T3P (50% in DMF, 0.868 ml, 1.487 mmol) and stirred at RT for 19 hours. The reaction mixture was concentrated in vacuo, dissolved in EtOAc and washed with water. The organic portion was dried (MgSO4) and concentrated in vacuo. Purification of the crude product by chromatography on silica eluting with 2% MeOH in DCM afforded the title compound;
