4-methoxytetrahydropyran-4-yl. A symmetrical alternative to the tetrahydropyranyl protecting group.

摘要: Abstract The possibility of using a symmetrical ketal function as an alternative to the tetrahydropyranyl protecting group has been examined. Although simple functions (derived from acetone and cyclohexanone) appear be too labile acidic hydrolysis useful groups, ketals oftetrahydro-4H-pyran-4-one have desired properties. preparation 4-methoxy-5,6-dihydro-2H-pyran is described; this reagent undergoes rapid acid-catalyzed addition alcoholic OH give tetrahydro-4H-pyran-4-one (methoxytetrahydropyranyl derivatives). preparations 2′-O-methoxytetrahydropyranyl-uridine -adenosine, 5′-O-methoxytetrahydropyranyl-thymidine are these derivatives obtained crystalline, in good yields.