[CH3:1][C:2]([C:5]1[CH:6]=[C:7]([S:16][CH2:17][CH2:18][C:19]([NH:21][NH2:22])=[O:20])[CH:8]=[C:9]([C:12]([CH3:15])([CH3:14])[CH3:13])[C:10]=1[OH:11])([CH3:4])[CH3:3].C(=O)(O)[O-].[Na+].[N:28]#[C:29]Br>O1CCOCC1.O.C(OCC)(=O)C>[NH2:28][C:29]1[O:20][C:19]([CH2:18][CH2:17][S:16][C:7]2[CH:8]=[C:9]([C:12]([CH3:13])([CH3:14])[CH3:15])[C:10]([OH:11])=[C:5]([C:2]([CH3:1])([CH3:3])[CH3:4])[CH:6]=2)=[N:21][N:22]=1A solution of 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoic acid hydrazide (0.50 g, 1.54 mmol) in dioxane (15 mL) is added to a solution of sodium bicarbonate (0.14 g, 1.62 mmol) in water (4 mL). Cyanogen bromide (0.17 g, 1.62 mmol) is added in four equal portions at 1-minute intervals, and stirring is continued for 5 hours. The reaction mixture is diluted with ethyl acetate and sequentially washed with aqueous sodium bicarbonate, water, and brine. Drying the organic phase over magnesium sulfate and evaporation provides a solid which is crystallized from ethyl acetate/hexane to give 0.42 g (78%) of 4-[[2-(5-amino-1,3,4-oxadiazol-2-yl)ethyl]thio]-2,6-bis(1,1-dimethylethyl)phenol, mp 172.0°-174.0° C.
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