1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → 3-[4-(5-{3-Chloro-4-[(1-methylethyl)oxy]phenyl}-1,2,4-oxadiazol-3-yl)-1H-indol-1-yl]propanoic acid

Participants

Reaction Steps

3-chloro-4-[(1-methylethyl)oxy]benzoic acid (D4) (117 mg) was added to EDCI (114 mg) and HOBT (81 mg) dissolved in DMF (2.5 ml). This was stirred at RT for 10 minutes and then ethyl 3-{4-[(hydroxyamino)(imino)methyl]-1H-indol-1-yl}propanoate (D57) (150 mg) in DMF (2.5 ml) was added and stirring continued at RT for 2 hours then at 80° C. overnight. The reaction mixture was evaporated to dryness and extracted from H2O (25 ml) with EtOAc (2×25 ml). The combined organics were evaporated and treated with 2 M aq. NaOH (10 ml) and EtOH (10 ml), stirred at 50° C. for 2 hours then evaporated to remove the EtOH. The remaining solution was acidified, filtered and the precipitate washed with EtO/H2O then recrystallised from hot EtOH/H2O then from DMSO. Washing with Et2O and MeOH gave the title compound (46 mg) as a white solid. δH (d6-DMSO, 400 MHz): 1.37 (6H, d), 2.81 (2H, t), 4.50 (2H, t), 4.89 (1H, septet), 7.08 (1H, d), 7.35 (1H, apparent t), 7.46 (1H, d), 7.60 (1H, d), 7.81 (1H, d), 7.94 (1H, d), 8.15 (1H, dd), 8.23 (1H, d). MS (ES−): C22H2035ClN3O4 requires 425; found 424 (M−H+).

Provenance & Evidence