Enantioselective synthesis of isoxazolidinyl thymine and cytosine nucleoides

• Published in: Tetrahedron letters 1996-07, Vol.37 (28), p.4877-4880
• Main Authors: Xiang, Yuejun, Gong, Youxiang, Zhao, Kang
• Format: Article
• Language: English
• ISSN: 0040-4039; 1873-3581
• DOI: 10.1016/0040-4039(96)00999-9

A diastereo- and enantioselective synthesis of isoxazolidinyl nucleosides ( 4) is described. The required isoxazolidine intermediate ( 16) was successfully prepared by the dioxolane-derived tautomerization of the corresponding lactol ( 13) which, in turn, was obtained from the reduction of the Michael adduct of N-methyl hydroxylamine and the unsaturated γ-lactone ( 5). A diastereo- and enantioselective synthesis of isoxazolidinyl nucleosides ( 4) is described. The required isoxazolidine intermediate ( 16) was successfully prepared by the dioxolane-derived tautomerization of the corresponding lactol ( 13) which, in turn, was obtained from the reduction of the Michael adduct of N-methyl hydroxylamine and the unsaturated γ-lactone ( 5).