[CH2:1]([O:3][C:4]([C:6]1[NH:7][C:8]2[C:13]([CH:14]=1)=[CH:12][C:11]([O:15][CH3:16])=[CH:10][CH:9]=2)=[O:5])C.[Mg].Cl>CO>[CH3:1][O:3][C:4]([CH:6]1[CH2:14][C:13]2[C:8](=[CH:9][CH:10]=[C:11]([O:15][CH3:16])[CH:12]=2)[NH:7]1)=[O:5]To 5-methoxy-1H-indole-2-carboxylic acid ethyl ester (5 g, 22.8 mmol) in MeOH (150 ml) was added magnesium turnings (2.2 g, 91.6 mmol, 4eq.) and the mixture vigorously mechanically stirred (10-30° C.) for 2 hr. 4N HCl was added (to pH1-2), then 25% NH4OH (to pH 7), and the mixture extracted with EtOAc (4×100 ml). The combined extracts were then washed with satd. NaCl solution (50 ml), dried (Na2SO4) filtered and evaporated. The crude green oil was chromatographed over SiO2 (Merck 230-400 mesh) eluting with EtOAc-nHexane (1:3) to afford the title compound (3.21g, 15.5 mmol, 68%) as a yellow solid Mp. 59-61° C., MS: m/e=207.1 (M+).
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