Oxalyl chloride (0.16 mL, 1.9 mmol) was reacted with 480 mg (1.5 mmol) of dl-2-[[2-methyl-1-(phenylmethyl)-1H-indol-4-yl]oxy]propanoic acid methyl ester and then reacted with anhydrous ammonia as in Example 1, Part F and the reaction product was dissolved in EtOAc, washed with water, dried (MgSO4) and concentrated. The residue was chromatographed on silica gel (eluted with EtOAc) to give 531 mg (90% yield) of dl-2-[[3-(2-amino-1,2-dioxoethyl)-2-methyl-1-(phenylmethyl)-1H-indol-4-yl]oxy]propanoic acid, methyl ester, melting at approximately 175° C.
