189209-27-6

911209-07-9

189209-27-6

General procedure for the synthesis of tert-butyl (17-amino-3,6,9,12,15-pentaoxaheptadecyl)carbamate from (17-azido-3,6,9,12,15-pentaoxaheptadecyl)carbamate: Compound 6 (5-PEG-Boc-Amino azide, 2.90 g, 8.0 mmol) was dissolved in a Parr reaction flask in 100 ml of ethyl acetate and 0.25 g of 10% Pd/C catalyst was added. The reaction mixture was stirred overnight under hydrogen atmosphere. Upon completion of the reaction, the reaction mixture was diluted with 200 ml of ethyl acetate and filtered through a diatomaceous earth pad to remove the catalyst. The filtrate was concentrated under reduced pressure to remove the solvent to give 2.41 g of crude product. The crude product was purified by silica gel column chromatography, first eluting using a mixed solvent system of 1% NH4OH/15% MeOH/84% CH2Cl2, and then switching to a mixed solvent system of 1% NH4OH/25% MeOH/74% CH2Cl2, and the target fractions were collected to give 1.37 g of purified product. The purified product was dissolved in toluene and concentrated again under reduced pressure to give 1.21 g (40% yield) of the target compound 7.