Sodium Hydroxide → 2-(5-hexyloxy-1H-indol-2-yl)thio-2-phenylpropionic acid
Reaction equation
[CH2:1]([O:7][C:8]1[CH:16]=[CH:15][C:14]2[N:13]3[C:17](=[O:27])[C:18]([CH3:26])([C:20]4[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=4)[S:19][C:12]3=[CH:11][C:10]=2[CH:9]=1)[CH2:2][CH2:3][CH2:4][CH2:5][CH3:6].[OH-:28].[Na+]>>[CH2:1]([O:7][C:8]1[CH:9]=[C:10]2[C:14](=[CH:15][CH:16]=1)[NH:13][C:12]([S:19][C:18]([C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1)([CH3:26])[C:17]([OH:28])=[O:27])=[CH:11]2)[CH2:2][CH2:3][CH2:4][CH2:5][CH3:6]Participants
3
Procedure
To 7-hexyloxy-2-methyl-2-phenylthiazolo[3,2-a]indol-3(2H)-one (3.92 g), 2N sodium hydroxide (70 ml) was added, and the mixture was heated and refluxed for 1.5 hours. The reaction mixture was allowed to cool, and the deposited crystalline matter was collected by filtration. The crystalline matter was dissolved in methanol. The solution was made acidic by adding concentrated hydrochloric acid under ice cooling, and the solvent was evaporated under reduced pressure. Water was added to the residue, and the mixture was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure, to give 3.81 g (yield: 93 %) of the desired compound as a colorless powder. The melting point was 100°-102° C.