Hydrochloric Acid → 2-[3-Cyclopentyl-2-(4-phenoxy-phenyl)-propionylamino]-thiazole-4-carboxylic acid methyl ester
Reaktionsgleichung
[CH:1]1([CH2:6][CH:7]([C:19]2[CH:24]=[CH:23][C:22]([O:25][C:26]3[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=3)=[CH:21][CH:20]=2)[C:8]([NH:10][C:11]2[S:12][CH:13]=[C:14]([C:16]([OH:18])=[O:17])[N:15]=2)=[O:9])[CH2:5][CH2:4][CH2:3][CH2:2]1.Cl.[CH3:33]O>>[CH3:33][O:17][C:16]([C:14]1[N:15]=[C:11]([NH:10][C:8](=[O:9])[CH:7]([C:19]2[CH:20]=[CH:21][C:22]([O:25][C:26]3[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=3)=[CH:23][CH:24]=2)[CH2:6][CH:1]2[CH2:5][CH2:4][CH2:3][CH2:2]2)[S:12][CH:13]=1)=[O:18]Komponenten
4
Versuchsvorschrift
A solution of 2-[3-cyclopentyl-2-(4-phenoxy-phenyl)-propionylamino]-thiazole-4-carboxylic acid (100 mg, 0.23 mmol) in methanol (10 mL) was treated with concentrated hydrochloric acid (1 mL) and then heated under reflux for 16 h. At this time, the reaction mixture was concentrated in vacuo. The residue was dissolved in ethyl acetate (10 mL) and then washed with water (5 mL). The aqueous layer was further extracted with ethyl acetate (3×5 mL). The combined organic extracts were dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230-400 mesh, 90/10 hexanes/ethyl acetate) afforded 2-[3-cyclopentyl-2-(4-phenoxy-phenyl)-propionylamino]-thiazole-4-carboxylic acid methyl ester (40 mg, 39%) as a white foam: EI-HRMS m/e calcd for C25H26N2O4S (M+) 450.1613, found 450.1615.