A solution of 2-(2,4-bis-benzyloxy-5-isopropyl-benzoyl)-2,3-dihydro-1H-isoindole-5-carboxylic acid (Preparation D6) (1.76 g, 3.39 mmol), EDC (0.78 g, 4.06 mmol), HOBT (0.55 g, 4.06 mmol), Et3N (1 ml, 6.78 mmol) and N,O-dimethylhydroxylamine hydrochloride (0.36 g, 3.72 mmol) in DMF (20 ml) was stirred at room temperature for 48 hours, then evaporated under vacuum. The crude material was dissolved in ethyl acetate and extracted twice with saturated NaHCO3, organics washed with brine, dried (MgSO4), filtered then evaporated to give 1.84 g of 2-(2,4-bis-benzyloxy-5-isopropyl-benzoyl)-2,3-dihydro-1H-isoindole-5-carboxylic acid methoxy-methyl-amide. MS: [M+H]+ 563.
