To a solution of 5-(5-(7-(trifluoromethyl)quinolin-4-yloxy)pentyloxy)-2-(hydroxymethyl)-4H-pyran-4-one 12 (240 mg, 0.57 mmol) in CH2Cl2 (15 mL) was added at 0° C. triethylamine (96 μL, 0.68 mmol), methanesulfonyl chloride (53 μL, 0.68 mmol). The solution was stirred at RT for 1.5 h. Dichloromethane (50 mL) was added and the solution was washed with water (3×100 mL), dried over MgSO4, filtered and evaporated. (5-(5-(7-(trifluoromethyl)quinolin-4-yloxy)pentyloxy)-4-oxo-4H-pyran-2-yl)methyl methanesulfonate 17 was obtained (260 mg, 91% yield) as a crude yellow oil.
