C([O:3][C:4](=[O:23])[CH2:5][NH:6][C:7]([C:9]1[C:10](=[O:22])[S:11][C:12]2[C:17]([C:18]=1[OH:19])=[CH:16][C:15]([Cl:20])=[CH:14][C:13]=2Br)=[O:8])C.[CH2:24]([B-](F)(F)F)[C:25]1[CH:30]=[CH:29][CH:28]=[CH:27][CH:26]=1.[K+].C(=O)([O-])[O-].[Cs+].[Cs+]>C1COCC1.O.C1(P([Pd-2](Cl)(Cl)P(C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>[CH2:24]([C:13]1[CH:14]=[C:15]([Cl:20])[CH:16]=[C:17]2[C:12]=1[S:11][C:10](=[O:22])[C:9]([C:7]([NH:6][CH2:5][C:4]([OH:3])=[O:23])=[O:8])=[C:18]2[OH:19])[C:25]1[CH:30]=[CH:29][CH:28]=[CH:27][CH:26]=1[(8-Bromo-6-chloro-4-hydroxy-2-oxo-2H-thiochromene-3-carbonyl)-amino]-acetic acid ethyl ester (22(d)) (500 mg, 1.2 mmol) was dissolved in THF-water (4:1; 20 mL total volume). To the solution was added potassium benzyltrifluoroborate (285 mg, 1.2 mmol), cesium carbonate (1.2 g, 3.6 mmol), and bis(triphenylphosphino) palladium(II) dichloride (168 mg, 0.24 mmol). The mixture was heated to reflux for six hours, cooled and concentrated. The residue was triturated with hot methanol (20 mL) and filtered to provide the title compound (395 mg.) MS ESI(−) m/e: 402.355, 403.783 (M−1).
Wird geladen…