Diisopropylethylamine → 15-[(3,5-Bis-tert-butoxycarbonylmethoxybenzyl)-(2-carboxyethyl)carbamoyl]pentadecanoic acid 4-methoxybenzyl ester

Participants

Reaction Conditions

Reaction Steps

Hexadecanedioic acid mono-(4-methoxy-benzyl) ester (0.4 g, 0.98 mmol) was dissolved in ethyl acetate (10 mL). N-Ethyl-N-(3-dimethylaminopropyl)-carbodiimide hydrochloride (0.187 g, 0.98 mmol) and 1-hydroxy-7-azabenzotriazole (0.134 g, 0.98 mmol) was added and the mixture was stirred at 50° C. for 1 hour. After cooling to room temperature, diisopropylethylamin (0.50 mL, 2.95 mmol) was added followed by 3-(3,5-Bis-tert-butoxycarbonylmethoxybenzylamino)propionic acid (0.432 g, 0.98 mmol). The mixture was stirred overnight under nitrogen at room temperature. The mixture was separated between ethyl acetate (200 mL) and water (2×100 mL). The organic phase was dried (Na2SO4), solvent removed in vacuo. The crude product was purified by RP-HPLC on C18-column, buffer A: 0.1% TFA, buffer B: MeCN+0.1% TFA; gradient 80-100% B to yield the title compound.

Provenance & Evidence