To solution of Boc-protected compound 77 (77 mg, 0.16 mmol) in DCM , was added 4N HCl in dioxane and the solution was left to stir at r.t. for 16 h. The reaction was then evaporated to dryness to quantitatively yield an amine intermediate as a HCl salt (63 mg, 0.16 mmol). The amine intermediate was dissolved in DMF (100 µL) followed by the addition of DIPEA . This was then added to a solution containing mesylate 75 2,5,7,10,13-pentaoxapentadecan-15-ol .