Water → {2-[2-(2-{2-[2-(4-{2-[2-(2-{2-[2-(9H-fluoren-9-yl-methoxycarbonylamino)-ethoxy]-ethoxy}-ethoxy)-ethoxy]-ethoxy}-phenoxy)-ethoxy]-ethoxy}-ethoxy)-ethoxy]-ethoxy}acetic acid tert-butyl ester

Participants

Reaction Steps

A solution of the crude product of Compound 28 obtained in Production Example 40 (175 mg, 0.311 mmol) in THF (1.2 ml) was cooled with ice, a solution of 9-fluorenylmethylsuccinimidyl carbonate (115 mg, 0.34 mmol) in THF (0.5 ml) was added thereto, triethylamine (62 mg, 0.62 mmol, 85 μl) was further added, and this was followed by stirring for 45 minutes. Water was added thereto to stop the reaction, after which extraction from ethyl acetate was conducted, and the combined organic phases were washed with saturated brine and dried with sodium sulfate. Filtration and concentration under reduced pressure were conducted, after which the concentrate was purified by silica gel column chromatography (Yamazen YFLC Gel, eluent; ethyl acetate-ethyl acetate solution containing 10% methanol) to yield Compound 29 (colorless oil 196 mg, 84%).

Provenance & Evidence