A mixture of (R)-4-[6-(4-tert-butyl-cyclohexyloxy)-naphthalen-2-yl]-3,4-dimethyl-oxazolidin-2-one (80 mg, 0.2 mmol) in 4.2 M of LiOH aqueous (1.5 mL, 6 mmol) and ethanol (1.5 mL) was heated at 120° C. for 5 hrs. The solvent was concentrated and the residue was washed with water to give white precipitate. The crude was purified with silica gel column eluted with 2 M NH3 in MeOH and DCM from 0 to 8% to give 7 mg of product, 10%. ESI-MS (M−30)+: 339.30, room temperature 1.57 min. 1H NMR (400 MHz, CDCl3) δ: 7.76˜7.70 (m, 3H), 7.51 (d, 1H), 7.17-7.12 (m, 2H), 4.27 (m, 1H), 3.88 (d, 1H), 3.71 (d, 1H), 2.32-2.23 (m, 5H), 1.89 (d, 2H), 1.62 (s, 3H), 1.44 (m, 2H), 1.25˜1.05 (m, 3H), 0.90 (s, 9H)
