Water → HCID 19348240, compound

Participants

Reaction Steps

A portion (55 mg) of the compound obtained in Example 226 was dissolved in anhydrous tetrahydrofuran (2 ml) and to the solution was added sodium hexamethyldisilazide (1.0 M tetrahydrofuran solution; 0.52 ml) under cooling with ice. After stirring for 30 minutes, methyl iodide (32.3 μl) was added to the mixture, followed by stirring for 15 minutes. After adding further sodium hexamethyldisilazide (1.0 M tetrahydrofuran solution; 0.35 ml), the mixture was stirred for 30 minutes. Then, methyl iodide (21.5 μl) was added and the mixture was stirred for additional 15 minutes. Water was added to the reaction mixture, followed by extraction with two portions of ethyl acetate. The organic layers were combined, washed with water and saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure and the residue was purified by preparative TLC (ethyl acetate/hexane=1:2) to yield 35 mg (61%) of the titled compound as a pale yellow solid. Specific rotation: [α]D +21° (25° C., c0.75, chloroform)

Provenance & Evidence