Hydrochloric Acid → H-Tyr(But)-Gly-OEt.HCl

Reaction equation

[NH:1](C(OCC1C=CC=CC=1)=O)[C@H:2]([C:15]([NH:17][CH2:18][C:19]([O:21][CH2:22][CH3:23])=[O:20])=[O:16])[CH2:3][C:4]1[CH:9]=[CH:8][C:7]([O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[CH:6][CH:5]=1.[H][H].[ClH:36]>CO>[NH2:1][C@H:2]([C:15]([NH:17][CH2:18][C:19]([O:21][CH2:22][CH3:23])=[O:20])=[O:16])[CH2:3][C:4]1[CH:9]=[CH:8][C:7]([O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[CH:6][CH:5]=1.[ClH:36]

Participants

Procedure

19.78 g (43 mmoles) of Z-Tyr(But)-Gly-OEt are dissolved in 200 ml of methanol. A Pd-on-charcoal catalyst is added to this solution and hydrogen is passed through the solution while stirring and adding approx. 2N methanolic HCL at pH 4.5 (autotitrator), until no further methanolic HCl is taken up. The catalyst is then filtered off and the filtrate is concentrated. The residue is stirred with ether and suction-drained. Yield 14.87 g (93.7%), melting point 140°-142°, [α]D22 =+30.9° (c=1, methanol).