Dimethylformamide → Methyl 3-(3-(4-methyl-3-(7-(3-oxobutyl)imidazo[1,2-a]pyridine-3-carboxamido)phenyl)-1,2,4-oxadiazol-5-yl)azetidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a stirring suspension of 7-(3-oxobutyl)imidazo[1,2-a]pyridine-3-carboxylic acid (86) (40 mg, 0.172 mmol) in anhydrous dichloromethane (2 mL) at 0° C. under Argon was added dropwise oxalyl chloride (16 uL, 0.189 mmol). Then, a drop of anhydrous N,N-dimethylformamide was added and the reaction mixture was stirred at 0° C. for 1 hour. The solvent was concentrated and the crude solid was dried under vacuum. Methyl 3-(3-(3-amino-4-methylphenyl)-1,2,4-oxadiazol-5-yl)azetidine-1-carboxylate (31) (25 mg, 0.086 mmol) and anhydrous pyridine (1 mL) were added to the acid chloride. The reaction was stirred to room temperature under Argon for 20 minutes. The crude product was purified by reverse phase preparative HPLC to give methyl 3-(3-(4-methyl-3-(7-(3-oxobutyl)imidazo[1,2-a]pyridine-3-carboxamido)phenyl)-1,2,4-oxadiazol-5-yl)azetidine-1-carboxylate (F73). 1H NMR (400 MHz, d6-DMSO) δ 10.24 (s, 1H), 9.44-9.41 (m, 1H), 8.73 (s, 1H), 8.09 (d, J=1.6 Hz, 1H), 7.85 (dd, J=1.6, 8.0 Hz, 1H), 7.73 (s, 1H), 7.51 (d, J=8.4 Hz, 1H), 7.32-7.29 (m, 1H), 4.39-4.35 (m, 2H), 4.31-4.24 (m, 1H), 4.21-4.17 (m, 2H), 3.59 (s, 3H), 2.98-2.91 (m, 4H), 2.37 (s, 3H), 2.13 (s, 3H). MS m/z 503.2 (M+1)+.

Provenance & Evidence