反应详情

Using the procedure for Example 11, 4'-thioribose 10 (0.35 g, 0.83 mmol), thymine (0.13 g, 1.05 mmol), potassium nonafluorobutanesulfonate (0.875 g, 2.54 mmol), HMDS (0.175 mL, 0.83 mmol), and TMS-Cl (0.4 mL, 3.2 mmol), following purification by preparative TLC (8:1 dichloromethane/acetonitrile) afforded 371 mg (92.5%) of 14, as a 4:3 α:β anomeric mixture; FAB MS 481 (M+H)+ ; 1H NMR (CDCl3) δ 9.65 (s, 1, NH), 7.7 (m, 4, ArH), 7.4 (m, 6, ArH), 6.3 (m, 1, 1'-Hα,β), 3.88 (m, 1, 4'-Hα), 3.82 (d, 1, 5'-Hβ), 3.66 (d+m, 2, 4'-Hβ, 5'-H α), 2.4-1.85 (m, 4, 2'-Hα,β 's, 3'-Hα,β 's), 1.95 (s, 3, 5β -CH2), 1.77 (s, 3, 5β -CH3), 1.11 (s, 9, β-t-butyl), 1.07 (s, 9, α-t-butyl).

1. custompurification by preparative TLC (8:1 dichloromethane/acetonitrile)