2-[(Chlorocarbonyl)(methyl)amino]ethyl ethyl carbonate → (+)-Ethyl 2-[[[5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridyl)methyl]sulfinyl]-3H-imidazo[4,5-b]pyridin-3-yl]carbonyl](methyl)amino]ethyl carbonate

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Reaction Conditions

Reaction Steps

To a solution of (+)-enantiomer (0.10 g) in tetrahydrofuran (5 mL), which was obtained by optically resolving 5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridyl)methyl]sulfinyl]-1H-imidazo[4,5-b]pyridine synthesized by a method described in JP-A 63-146882 with preparative HPLC, were added 2-[(chlorocarbonyl)(methyl)amino]ethyl ethyl carbonate (0.081 g) obtained in Reference Synthetic Example 34, triethylamine (0.080 mL) and 4-dimethylaminopyridine (0.007 g), and stirred at 50° C. for 18 hrs. The reaction solution was concentrated under reduced pressure, and to the residue was added water (30 mL), and extracted with ethyl acetate (50 mL). The ethyl acetate layer was washed with saturated brine (30 mL), and dried over anhydrous sodium sulfate. After concentrating under reduced pressure, the residue was purified with basic silica gel column chromatography (eluted with ethyl acetate:hexane=2:1) to give a mixture of 2:1 of title compound and (+)-ethyl 2-[[[5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridyl)methyl]sulfinyl]-1H-imidazo[4,5-b]pyridin-1-yl]carbonyl](methyl)amino]ethyl carbonate as colorless oil (0.115 g).

Provenance & Evidence