Diisopropylethylamine → 4-{[(2-tert-Butoxycarbonylethyl)-(15-tert-butoxycarbonyl-pentadecanoyl)amino]methyl}benzoic acid

Participants

Reaction Conditions

Reaction Steps

Hexadecanedioic acid mono-tert-butyl ester (0.3 g, 0.88 mmol) was dissolved in ethyl acetate. N-Ethyl-N-(3-dimethylaminopropyl)-carbodiimide hydrochloride (0.167 g, 0.88 mmol) and 1-hydroxy-7-azabenzotriazole (0.119 g, 0.88 mmol) was added and the mixture was stirred at 50° C. for 1 hour. After cooling to room temperature, diisopropylethylamin (0.45 mL, 2.63 mmol) was added followed by 4-[(2-tert-Butoxycarbonylethylamino)methyl]benzoic acid (0.489 g, 1.75 mmol). The mixture was stirred overnight under nitrogen at room temperature. The mixture was separated between ethyl acetate (100 mL) and water (2×50 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 (145 mg, 27%).

Provenance & Evidence