C([O:8][C:9]1[CH:14]=[CH:13][C:12]([C@@H:15]([O:43][Si](CC)(CC)CC)[CH2:16][NH:17][CH2:18][CH2:19][C:20]2[CH:25]=[CH:24][C:23]([S:26]([CH2:29][C:30]3[N:34]=[C:33]([C:35]4[CH:40]=[CH:39][C:38]([O:41][CH3:42])=[CH:37][CH:36]=4)[O:32][N:31]=3)(=[O:28])=[O:27])=[CH:22][CH:21]=2)=[CH:11][C:10]=1[NH:51][S:52]([CH3:55])(=[O:54])=[O:53])C1C=CC=CC=1.C[Si](I)(C)C.S(=O)(=O)(O)[O-].[Na+]>C(#N)C>[OH:8][C:9]1[CH:14]=[CH:13][C:12]([C@@H:15]([OH:43])[CH2:16][NH:17][CH2:18][CH2:19][C:20]2[CH:21]=[CH:22][C:23]([S:26]([CH2:29][C:30]3[N:34]=[C:33]([C:35]4[CH:40]=[CH:39][C:38]([O:41][CH3:42])=[CH:37][CH:36]=4)[O:32][N:31]=3)(=[O:27])=[O:28])=[CH:24][CH:25]=2)=[CH:11][C:10]=1[NH:51][S:52]([CH3:55])(=[O:53])=[O:54]To a solution of the O-protected amino alcohol of Example 26 (0.292 g, 0.362 mmol) in acetonitrile (3 mL) was added 5 equivalents of trimethylsilyl iodide (0.26 mL, 0.1.81 mmol). The reaction mixture was heated to 50° C. for 16 h. TLC shows the absence of starting material, so 1 mL of dilute aqueous sodium bisulfate (Na2S2O5) solution was added to the room temperature reaction mixture and it was stirred vigorously for 15 minutes. The reaction mixture was evaporated in vacuo to dryness and the residue was flash chromatographed (silica gel; dichloromethane/chloroform/methanol: 12/3/2) to afford 0.140 g of the title compound as a light yellow crystalline solid.
Loading…