To a solution of methyl-2-hydroxy-3-(5-methoxypyridin-2-ylamino)benzoate 0.91 g (3.3 mmol) of step 4 in dimethylformamide 10 mL were (R)-glycidyl nosylate 1.0 g (4 mmol) and K2CO3 0.5 g (3.6 mmol), followed by stirring at room temperature for 12 hrs. The reaction mixture was concentrated in a vacuum, diluted with ethylacetate, and washed with distilled water and a saturated NaCl solution. After drying over magnesium sulfate and vacuum concentration, purification by column chromatography (developing solvent: ethylacetate/hexane=1/2) afforded 0.95 g of the title compound (yield 87%).
