Ethanol → L-prolyl-L-alanyl-L-proline

Reaction equation

C([O:8][C:9](=[O:27])[C@@H:10]1[CH2:14][CH2:13][CH2:12][N:11]1[C:15](=[O:26])[C@H:16]([CH3:25])[NH:17][C:18](=[O:24])[C@@H:19]1[CH2:23][CH2:22][CH2:21][NH:20]1)C1C=CC=CC=1.C(O)C.[H][H]>>[NH:20]1[CH2:21][CH2:22][CH2:23][C@H:19]1[C:18]([NH:17][C@H:16]([C:15]([N:11]1[CH2:12][CH2:13][CH2:14][C@H:10]1[C:9]([OH:27])=[O:8])=[O:26])[CH3:25])=[O:24]

Participants

Reactant 3

HCID 702Ethanol

HCID 86749330L-prolyl-L-alanyl-L-proline benzyl ester

HCID 178418361HCID 178418361, compound

Product 1

HCID 9817252L-prolyl-L-alanyl-L-prolineYield 73%

Procedure

Into a Parr flask flushed with argon containing 450 mg of 10% palladium on charcoal catalyst was added a solution of Ac-L-prolyl-L-alanyl-L-proline benzyl ester in (1.0 g, 2.41 mmol) absolute ethanol (100 ml). The contents were shaken under 40 psi of hydrogen overnight at room temperature. The mixture was filtered through celite and the filtrate concentrated on a rotary evaporator to give crude Ac-L-prolyl-L-alanyl-L-proline which was crystallized from tetrahydrofuran-methanol-ether to give the desired product (0.57 g) in 73% yield.