Sodium Sulfite → HCID 90449435, compound

The 1′-acetyl-N-(5-chlorothiazol-2-yl)-5-(1-hydroxyethyl)spiro[indoline-3,3′-pyrrolidine]-1-carboxamide (22.3 mg, 0.053 mmol) obtained in Step 2 of Example 401 was dissolved in methylene chloride (0.5 mL). Thereafter, Dess-martin periodinane (27.0 mg, 0.0635 mmol) was added to the above obtained solution at room temperature, and the thus obtained mixture was then stirred at the same temperature as above for 1 hour. Thereafter, an aqueous solution of sodium sulfite was added to the reaction solution, and the mixed solution was then extracted with chloroform. The organic layer was washed with brine, and was then dried over anhydrous sodium sulfate, followed by concentration in vacuo. The obtained residue was purified by silica gel column chromatography (chloroform:methanol=10:1) to obtain the captioned compound (21.7 mg, 99%) in the form of a white solid.