Lithium Hydroxide → N-(E)-[1-oxo-2-(mercaptomethyl)-3-phenylpropenyl]-beta-alanine
Reaction equation
[O:1]=[C:2]([NH:16][CH2:17][CH2:18][C:19]([O:21]CC1C=CC=CC=1)=[O:20])/[C:3](/[CH2:11][S:12]C(=O)C)=[CH:4]\[C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=1.[Li+].[OH-]>C1COCC1.O>[O:1]=[C:2]([NH:16][CH2:17][CH2:18][C:19]([OH:21])=[O:20])/[C:3](/[CH2:11][SH:12])=[CH:4]\[C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=1Participants
4
Procedure
To a solution of 2 mmol of the diester obtained in Example 1 (step D) dissolved in a THF/H2O (75/25) mixture, are added, at 0° C. and under an argon atmosphere, 8 mmol of LiOH with stirring for 2 hours. The THF is evaporated off and the aqueous phase is washed with ether and acidified with aqueous 3N HCl solution. It is extracted with ether and the ether extract is washed with saturated aqueous NaCl solution and dried over MgSO4. It is filtered and evaporated. Yield: 63% (after flash chromatography, eluent: ether) m.p. 80° C. IR (nujol): 3340, 1700, 1630, 1610 cm-1. 1H NMR (acetone D6): 10.90 to 10.60 (m, 1H); 7.65 (m, 1H); 7.45 to 7.35 (m, 5H); 7.20 (s, 1H); 3.75 to 3.50 (m, 4H); 2.60 (t, 2H, J=6.75 Hz); 2.30 (t, 1H, J=7.50 Hz) Microanalysis: C13H15O3NS Calc. % C=58.85 H=5.70 N=5.28 Found. % C=58.68 H=5.78 N=5.17