Process for the preparation of 2,2'-andhydro- and 2'-keto-1-(3',5'-di-o-protected-beta -d-arabinofuranosyl) nucleosides

摘要

A process for the preparation of compounds of the formula: wherein -Pg and R are protecting groups and B is a nucleobase. The process uses protected nucleobases to form 2,2'-anhydro nucleosides having the formula which are hydrolyzed to 2'-hydroxy intermediates which are then oxidized to the desired 2'-keto compounds. The compounds and intermediates are useful as antiviral and antitumor agents and as intermediates to 2,2'-anhydro-1-( beta -D-arabinofuranosyl)cytosine (anhydro-ara-C) and 1- beta -D-arabinofuranosylcytosine (Ara-C).