[OH:1][C@@H:2]1[C@H:6]2[N:7]([C:21]([O:23][C:24]([CH3:27])([CH3:26])[CH3:25])=[O:22])[CH2:8][C@@H:9]([O:10]S(C3C=CC(C)=CC=3)(=O)=O)[C@H:5]2[O:4][CH2:3]1.[O-][CH2:29][CH3:30].[Na+]>C(O)C.C(=O)([O-])O.[Na+]>[CH2:29]([O:10][C@H:9]1[CH2:8][N:7]([C:21]([O:23][C:24]([CH3:25])([CH3:26])[CH3:27])=[O:22])[C@@H:6]2[C@@H:2]([OH:1])[CH2:3][O:4][C@H:5]12)[CH3:30]A stirred mixture of tosylate (35b) (20 mg, 0.05 mmol), ethanol (1 mL) and sodium ethoxide solution in ethanol (21% wt, 94 μL, 0.25 mmol) was heated under an atmosphere of argon at 80° C. for 16 hours. The mixture was diluted with aqueous saturated sodium hydrogen carbonate solution (10 mL) then extracted with tert-butyl methyl ether (3×5 mL). The organic phase was dried (MgSO4), filtered and reduced in vacuo to leave an oil. Flash chromatography over silica, eluting with diethyl ether:pentane mixtures 65:35 to 83:17 gave ethoxyalcohol (59) as a pale yellow solid (1 mg, 7%). TLC (Rf=0.50, Et2O); analytical HPLC main peak, Rt=15.35 min., HPLC-MS 218.1 [M+2H−tBu]+, 296.1 [M+Na]+, 569.3 [2M+Na]+.
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