Crystalline (S) -isopropyl 2 - (((S) - (((2R, 3R, 4R, 5R) -5- (2,4-dioxo-3,4-DIHYDROPYRIMIDIN- 1- (2 H) -yl) - 4-fluoro-3-hydroxy-4-methyltetrahydrofuran-2-yl) methoxy) (phenoxy) phosphoryl) amino) propanoate

摘要

Disclosed herein is a process for preparing an enantiomerically- or a diastereomerically enriched phosphorus-containing active, salt, or pharmaceutically acceptable salt thereof, of formula I-1 , which comprises the steps of: (a) reacting a protected or unprotected Active with a base to form a salt of said active and then reacting said salt with an enantiomerically- or a diastereomerically enriched compound of formula II-1 wherein the Active is a nucleoside, a nucleoside-analog, or a non-nucleoside.