4-Methylmorpholine → tert-butyl 2-(4-(2-(4-methoxy-2-(trifluoromethyl)phenyl)acetamido)-N-(4-(3-(4'-methyl-[1,1'-biphenyl]-4-yl)-1,2,4-oxadiazol-5-yl)benzyl)benzamido)acetate

Participants

Reaction Steps

To a stirring solution of 4-((N-(2-(tert-butoxy)-2-oxoethyl)-4-(2-(4-methoxy-2-(trifluoromethyl)phenyl)acetamido)benzamido)methyl)benzoic acid INT-37 (150 mg, 0.25 mmol) in dioxane (4 mL) were added N-methylmorpholine (60.0 μl, 0.55 mmol) and isobutyl chloroformate (34.0 μl, 0.26 mmol). After stirring at room temperature for 1 h, the reaction mixture was added drop wise to a stirring solution of N′-hydroxy-4′-methyl-[1,1′-biphenyl]-4-carboximidamide INT-40 (62.0 mg, 0.275 mmol) in dioxane (2 mL) and DMF (2 mL). The reaction mixture was allowed to stir at room temperature for 1 h, then heated to 90° C. for 2 h, and then heated to 120° C. for 16 h. The reaction mixture was allowed to cool to room temperature then poured into NaHCO3 (20 mL) and extracted with DCM (3×20 mL). The combined organic extracts were dried over MgSO4 and concentrated. The crude product was purified by column chromatography (EA/isohexanes) to yield 77 mg (35%) of tert-butyl 2-(4-(2-(4-methoxy-2-(trifluoromethyl)phenyl)acetamido)-N-(4-(3-(4′-methyl-[1,1′-biphenyl]-4-yl)-1,2,4-oxadiazol-5-yl)benzyl)benzamido)acetate INT-41. LCMS-ESI (m/z) calculated for C45H41F3N4O6: 791; no m/z observed, tR=3.26 min (Method 10). 1H NMR (400 MHz, DMSO) δ 10.34 (s, 1H), 8.35-8.04 (m, 4H), 8.04-7.80 (m, 2H), 7.80-7.28 (m, 11H), 7.28-7.08 (m, 2H), 4.80 (s, 1H), 4.70 (s, 1H), 4.00 (s, 2H), 3.92-3.79 (m, 5H), 2.40 (s, 3H), 1.47 (s, 4.5H), 1.33 (s, 4.5H).

Provenance & Evidence