To a stirred solution of 1,1,1-tris(hydroxymethyl)ethane (13.1 g, 109 mmol), (2S)-2-(6-methoxy(2-naphthyl))propanoic acid (naproxen, 5.00 g, 21.7 mmol), 1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride (4.80 g, 25 mmol), and N,N-dimethylaminopyridine (DMAP, 20 mg, catalytic amount) in acetonitrile (200 mL) was added triethylamine (4.2 mL, 30 mmol). The reaction mixture was stirred at ambient temperature for 25 hours, filtered, and the filtrate was concentrated to dryness. The residue was diluted with EtOAc, washed with 1N HCl (2×), saturated NaHCO3, and brine, dried over Na2SO4, filtered, and concentrated. The resulting material was purified by crystallization (2×) from EtOAc/Hexanes (1:3 v:v) to give the title compound (4.72 g, 66% yield) as white flakes. Mp 105° C. 1H NMR (300 MHz, CDCl3) δ 7.72 (d, J=2.0 Hz, 1H), 7.69 (d, J=2.5 Hz, 1H), 7.66 (s, 1H), 7.39 (dd, J=8.5, 1.7 Hz, 1H), 7.17-7.10 (m, 2H), 4.25 (d, J=11.3 Hz, 1H), 4.09 (d, J=11.3 Hz, 1H), 3.90 (s, 3H), 3.88 (q, J=7.1 Hz, 1H), 3.46-3.25 (m, 4H), 2.65-2.55 (m, 2H), 1.60 (d, J=7.1 Hz, 3H), 0.67 (s, 3H). 13C NMR (75 MHz, CDCl3) δ175.8, 157.7, 135.3, 133.8, 129.2, 128.9, 127.3, 126.0, 119.2, 105.6, 67.7, 67.5, 66.8, 55.3, 45.6, 40.9, 18.1, 16.7. LRMS (API-TIS) m/z 350.2 ((M+NH4)+).
