N-Benzyloxycarbonyl-L-prolyl-L-alanine → 1-[(Benzyloxy)carbonyl]-L-prolyl-L-alanyl-N-ethyl-L-alaninamide

Participants

Reaction Steps

The condensation of Z-Pro-Ala with Ala-NH-Et by the procedure in Example 7 yields Z-Pro-Ala-Ala-NH-Et; m.p. 219°-220° C. from 2-propanol--AcOEt); (α)D20 =-36.2°; c=0.2 (dimethylformamide). This intermediate is successively converted, as described in Example 2, into (1) BOC-Asp(Obzl)-Pro-Ala-Ala-NH-Et, m.p. 133°-136° C. (AcOEt--petroleum ether), (α)D20 =-61.1°, c=0.2 (MeOH); (2) Asp(OBzl)-Pro-Ala-Ala-NH-Et.HCl, m.p. 189°-193° C. (MeOH--Et2O), and (3) Ac-Asp(OBzl(-Pro-Ala-Ala-NH-Et, m.p. 191°-193° C. (AcOEt--petroleum ether), (α)D20 =-68.5°, c=0.2 (MeOH). Hydrogenolysis of the latter product by the procedure in Example 1 yields the title compound, Nα -Acetylaspartyl-prolyl-alanyl-alanine ethylamide; m.p. 153°-155° C. (melting begins at 143° C.).

Provenance & Evidence