Diisopropylethylamine → 5-{2-[(2-tert-Butoxycarbonyl-ethyl)-(17-tert-butoxycarbonyl-heptadecanoyl)-amino]-acetylamino}-isophthalic acid 1-tert-butyl ester 3-(2,5-dioxo-pyrrolidin-1-yl) ester

Participants

Reaction Steps

5-{2-[(2-tert-Butoxycarbonyl-ethyl)-(17-tert-butoxycarbonyl-heptadecanoyl)-amino]-acetylamino}-isophthalic acid mono-tert-butyl ester (214 mg) was dissolved in dry THF and TSTU (0.105 mg) and DIPEA (0.1 ml) was added. The mixture was stirred at room temperature under nitrogen. After 20 h the reaction mixture was concentrated. The residue was redissolved in EtOAc and filteret. The filtrate was extracted with 0.1 N HCl (2×) and brine (1×), dried (Na2SO4) and concentrated to give 5-{2-[(2-tert-Butoxycarbonyl-ethyl)-(17-tert-butoxycarbonyl-heptadecanoyl)-amino]-acetylamino}-isophthalic acid 1-tert-butyl ester 3-(2,5-dioxo-pyrrolidin-1-yl) ester as a yellow sirup in 90% yield (218 mg).

Provenance & Evidence