1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → Ethyl 3-[5-(5-{5-chloro-6-[(1-methylethyl)oxy]-3-pyridinyl}-1,2,4-oxadiazol-3-yl)-1H-indol-2-yl]propanoate

Participants

Reaction Conditions

Reaction Steps

EDCI (92 mg) and HOBT (80 mg) were added to a solution of 5-chloro-6-[(1-methylethyl)oxy]-3-pyridinecarboxylic acid (52 mg) in THF (6 mL). The resulting mixture was stirred for 1 hour followed by addition of ethyl 3-{5-[(Z)-(hydroxyamino)(imino)methyl]-1H-indol-2-yl}propanoate (D31) (100 mg). The resulting mixture was stirred for 3 hours followed by addition of TBAF (251 mg). The reaction vessel was sealed, and heated at 120° C. in the microwave for 3 hours. THF was removed. The residue was dissolved in EtOAc. The organic solution was washed with saturated aqueous sodium bicarbonate solution. The organic solution was dried over anhydrous sodium sulfate. The dried solution was concentrated. The residue was purified by column chromatography to afford ethyl 3-[5-(5-{5-chloro-6-[(1-methylethyl)oxy]-3-pyridinyl}-1,2,4-oxadiazol-3-yl)-1H-indol-2-yl]propanoate (D115) (54 mg). MS (ES): C23H23ClN4O4 requires 454; found 455.2 (M+H+).

Provenance & Evidence