| 摘要 |
<p>A process for the preparation of compounds of the general formula I: <CHEM> wherein R represents hydrogen or a protecting group, which comprises selective reduction of a compound of the general formula II: <CHEM> wherein R is as defined above, and Hal represents halogen; with optional total or partial inversion of the hydroxyl or protected hydroxyl substituent; and when R is a protecting group, optional removal of the protecting group from the compound of general formula I.</p> |
