HOBT (161 mg) and EDCI (203 mg) were added to a solution of 6-[(1-methylethyl)oxy]-5-(trifluoromethyl)-3-pyridinecarboxylic acid (132 mg) in THF (4 mL). The resulting solution was stirred for 2 hours. Ethyl 3-{4-fluoro-7-[(Z)-(hydroxyamino)(imino)methyl]-1H-indol-3-yl}propanoate (D45) (210 mg) in THF (4 mL) was added, and the reaction mixture was stirred at RT overnight. TBAF (770 mg) was then added. The reaction vessel was sealed and heated in Biotage Initiator using initial normal to 120° C. for 2.5 hours. After cooling, the reaction was quenched with water, and extracted with EtOAc for 3 times. The combined organic solution was washed with brine, and dried over anhydrous sodium sulfate. The dried solution was concentrated. The residue was purified by column chromatography (10% EtOAc in hexane) to afford ethyl 3-(4-fluoro-7-{5-[6-[(1-methylethyl)oxy]-5-(trifluoromethyl)-3-pyridinyl]-1,2,4-oxadiazol-3-yl}-1H-indol-3-yl)propanoate (D49) (162 mg) as a pale white solid. δH (CDCl3, 400 MHz): 1.25 (3H, t), 1.46 (6H, d), 2.76 (2H, t), 3.24 (2H, t), 4.15 (2H, q), 5.59 (1H, m), 6.92 (1H, dd), 7.15 (1H, d), 8.05 (1H, dd), 8.64 (1H, d), 9.17 (1H, d), 9.65 (1H, br s). MS (ES): C24H22F4N4O4 requires 506; found 507.2 (M+H+).
