Ethylmorpholine → L-Pyroglutamyl-L-alanine amide

Reaction equation

ClC1C(O[C:9](=[O:16])[C@@H:10]2[CH2:14][CH2:13][C:12](=[O:15])[NH:11]2)=C(Cl)C(Cl)=C(Cl)C=1Cl.Cl.[NH2:22][C@H:23]([C:25]([NH2:27])=[O:26])[CH3:24].C(N1CCOCC1)C>CN(C)C=O>[NH:11]1[C:12](=[O:15])[CH2:13][CH2:14][C@H:10]1[C:9]([NH:22][C@H:23]([C:25]([NH2:27])=[O:26])[CH3:24])=[O:16]

Participants

Procedure

3.75 g (10 mmols) of L-pyroglutamic acid pentachlorophenyl ester were stirred in 40 ml of dimethyl formamide with 1.5 g (12 mmols) of L-alanine amide hydrochloride and 1.54 ml (12 mmols) of N-ethylmorpholine for 4 hours. The solvent was distilled off in vacuo. The residue was dissolved in methanol and the solution was stirred successively with strongly basic and strongly acid ion exchangers. The exchanger was removed by filtration and concentration to dryness followed. The residue was triturated with ethyl acetate, dissolved in a little ethanol and precipitated with petroleum ether in the form of a resin that solidified under petroleum ether. Yield: 1.2 g, chromatographically unfirom without sharp melting point.