Boron tribromide → 3-(1-((3,5-dimethylisoxazol-4-yl)methyl)-1H-pyrazol-4-yl)-1-(3-hydroxy-5-methoxybenzyl)-5,5-dimethylimidazolidine-2,4-dione

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Reaction Conditions

Reaction Steps

1-(3,5-dimethoxybenzyl)-3-(1-((3,5-dimethylisoxazol-4-yl)methyl)-1H-pyrazol-4-yl)-5,5-dimethylimidazolidine-2,4-dione (Example 12-18) (114 mg, 0.252 mmol) was dissolved in dichloromethane (1 mL). The mixture was cooled down to −78° C. and boron tribromide (1.0 M solution in dichloromethane, 1.25 mL) was added dropwise. After complete addition, the mixture was allowed to warm to room temperature and stirring continued for 3 hours. The mixture was quenched with water and the organic phase was separated, dried over anhydrous Na2SO4, filtered and evaporated under reduced pressure. The residue was suspended in methanol (1 mL) and purified by reverse phase HPLC (25 minute gradient: acetonitrile/water). Yield 47% (45 mg), white solid. NMR (DMSO-d6, 400 MHz): □s, 6H), 2.16 (s, 3H), 2.42 (s, 3H), 3.67 (s, 3H), 4.43 (s, 2H), 5.20 (s, 2H), 6.22 (t, J=2.4 Hz, 1H), 6.39 (m, 2H), 7.83 (d, J=0.4 Hz, 1H), 8.21 (s, 1H), 9.40 (br s, 1H). Mp. 72-74° C. MS 440 (MH+). The title compound was shown to inhibit hT2R08 bitter receptor and had an IC50 of 0.02 μM.

Provenance & Evidence