{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 → {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

Participants

Reaction Steps

To Compound 29 (196 mg, 0.25 mmol), 5% hydrated trifluoroacetic acid (1.5 ml) was added at room temperature; this was followed by stirring for 5 minutes. Toluene (about 1 ml) was added; after concentration under reduced pressure, the concentrate was purified by silica gel column chromatography (Yamazen YFLC Gel, eluent; chloroform containing 3% methanol-ethyl acetate solution containing 10% methanol) to yield Compound 30 (colorless oil 175 mg, 96%).

Provenance & Evidence