4-Bromo-2-sulfanylbenzoic acid → tert-Butyl 3-[2-(7-bromo-4-oxo-4H-1,3-benzothiazin-2-yl)-4-pyridyl]propanoate
Reaktionsgleichung
[C:1]([C:3]1[CH:8]=[C:7]([CH2:9][CH2:10][C:11]([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12])[CH:6]=[CH:5][N:4]=1)#[N:2].[Br:18][C:19]1[CH:20]=[C:21]([SH:28])[C:22](=[CH:26][CH:27]=1)[C:23](O)=[O:24]>N1C=CC=CC=1>[Br:18][C:19]1[CH:27]=[CH:26][C:22]2[C:23](=[O:24])[N:2]=[C:1]([C:3]3[CH:8]=[C:7]([CH2:9][CH2:10][C:11]([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12])[CH:6]=[CH:5][N:4]=3)[S:28][C:21]=2[CH:20]=1Komponenten
4
Versuchsvorschrift
tert-Butyl 3-(2-cyano-4-pyridyl)propanoate (1.3 g, 5.6 mmol) and 4-bromothiosalicylic acid (1.8 g, 8.0 mmol) were dissolved in pyridine (20 ml), and the mixture was refluxed for 18 hrs. The solvent was evaporated, and the residue was subjected to a silica gel column chromatography. The fractions eluted with hexane-ethyl acetate (3:2, v/v) were collected, concentrated and recrystallized from hexane-tetrahydrofuran to give the titled compound (0.63 g, 25%) as white crystals.