Acetic Acid → HCID 7299381, Verbindung

Reaktionsgleichung

C[O:2][C:3](=[O:28])[C@H:4]([CH2:24][CH:25]([CH3:27])[CH3:26])[NH:5][C:6](=[O:23])[C@@H:7]([CH2:19][CH:20]([CH3:22])[CH3:21])[NH:8][C:9]([O:11][CH2:12][C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1)=[O:10].O.[OH-].[Li+].C(O)(=O)C>C1COCC1.O>[CH2:12]([O:11][C:9]([NH:8][C@@H:7]([C:6]([NH:5][C@H:4]([C:3]([OH:28])=[O:2])[CH2:24][CH:25]([CH3:26])[CH3:27])=[O:23])[CH2:19][CH:20]([CH3:22])[CH3:21])=[O:10])[C:13]1[CH:14]=[CH:15][CH:16]=[CH:17][CH:18]=1

Komponenten

Versuchsvorschrift

N-(Benzyloxycarbonyl)-D-leucyl-L-leucine methyl ester (Example 29A, 1.12 g, 2.85 mmol) is provided at 0° C. in THF/water 2:1 (15 ml) and then lithium hydroxide monohydrate (140 mg, 5.71 mmol, 2 equivalents) is added. When the HPLC chromatogram (Method 2) shows complete conversion (about 1 h), the reaction mixture is adjusted to pH 3-4 with acetic acid, concentrated in vacuo under cold conditions and then freed of solvent by freeze-drying overnight. The crude product is purified by means of preparative HPLC (Method 13) whereby 958 mg (88.7% of theory) of the title compound are obtained.