Ethylmorpholine → HCID 25425656, compound

Participants

Reaction Conditions

Reaction Steps

6.5 ml (approx. 50 mmoles) of N-ethylmorpholine and 11 g of dicyclohexylcarbodiimide are added at 0° C. to a solution in 100 ml of dimethylformamide of 12.64 g (50 mmoles) of H-Trp-OMe.HCl, 6.75 g (50 mmoles) of 1-hydroxybenzotriazole and 12.55 g (50 mmoles) of Z-Val-OH. The mixture is stirred for one hour at 0° C. and is allowed to stand overnight at room temperature. On the following day the precipitate is filtered off and the filtrate is stirred with 50 ml of saturated NaHCO3 solution and 1,000 ml of water. The mixture is cooled to 4° C. and the precipitate is filtered off. While still wet, the precipitate is dissolved in ethyl acetate. The ethyl acetate phase is extracted by shaking with water, saturated NaHCO3 solution, KHSO4 /K2SO4 solution and again with saturated NaHCO3 solution and is dried over Na2SO4 and concentrated to a small residue. The peptide is precipitated from the concentrated solution with petroleum ether. The precipitate is filtered off and dried. Yield 19.1 g (84%), melting point 146°-148°, [α]D22 =-13.9° (c=1, in methanol).

Provenance & Evidence