Methanaminium, N-((dimethylamino)(3H-1,2,3-triazolo(4,5-b)pyridin-3-yloxy)methylene)-N-methyl-, hexafluorophosphate(1-) (1:1) → (R)-ethyl 4-(5'-fluoro-2'-methoxybiphenyl-4-yl)-3-(oxazole-5-carboxamido)butanoate

Participants

Reaction Steps

To a solution of oxazole-5-carboxylic acid (70 mg, 0.61 mmol) in DMF (1.5 mL) and DCM (1.5 mL) is added (R)-ethyl 3-amino-4-(5′-fluoro-2′-methoxybiphenyl-4-yl)butanoate hydrochloride, intermediate 8-3, (150 mg, 0.41 mmol), HATU (233 mg, 0.61 mmol), and TEA (284 μL, 2.04 mmol). After stirring for 2 hours, the reaction is quenched with H2O, and the crude is diluted with EtOAc, the organic layer is washed with brine, dried over Na2SO4, filtered, and concentrated under reduced pressure. The obtained residue is purified by RP-HPLC (SunFire C18, H2O (0.1% TFA)/CH3CN), and then lyophilized to give (R)-ethyl 4-(5′-fluoro-2′-methoxybiphenyl-4-yl)-3-(oxazole-5-carboxamido)butanoate (157 mg). HPLC retention time=1.50 minutes (condition A); MS (m+1)=427.4; 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 1.19 (t, J=7.2 Hz, 3 H) 2.46-2.62 (m, 2 H) 2.86 (dd, J=13.6, 8.1 Hz, 1 H) 3.02 (dd, J=13.6, 6.1 Hz, 1 H) 3.67 (s, 3 H) 4.05-4.15 (m, 2 H) 4.52-4.69 (m, 1 H) 6.76-6.82 (m, 1 H) 6.83-6.96 (m, 2 H) 7.11-7.21 (m, 3 H) 7.37 (d, J=8.1 Hz, 2 H) 7.61 (s, 1 H) 7.80 (s, 1 H)

Provenance & Evidence