Triethylamine → Z-Thr(tBu)-Phe-Pro-Gln-Thr(tBu)-Ala-Ile-Gly-OH

Participants

Reaction Conditions

Reaction Steps

2.8 g of Z-Thr(tBu)-Phe-Pro-OH and 0.77 ml of absolute triethylamine are dissolved in 30 ml of dry tetrahydrofurane and the solution, cooled to -10°C, is added dropwise to 700 mg of isobutyl chlorocarbonate, care being taken for the temperature not to exceed -5°C. The mixture is then left for 10 minutes at -10°C and is thereafter added to a solution, precooled to -20°C, of 2.5 g of H-Gln-Thr(tBu)-Ala-Ile-Gly-OH.HCl in 65 ml of dimethylformamide-water (9:1). 1.2 ml of triethylamine are then added dropwise and the mixture is left for 1 hour at -10°C and for 18 hours at 0°C. It is thereafter concentrated, in vacuo and then in a high vacuum at 40°C bath temperature, to a volume of about 15 ml and then precipitated by adding 100 ml of ice-cold 2 % strength acetic acid. The product is filtered off, washed with ice water, dried and twice reprecipitated from methanol-water to purify it; yield 3.9 g of octapeptide derivative.

Provenance & Evidence