Disclosed herein are nucleosides, nucleotides and nucleotide analogs, methods of synthesizing the same and methods of treating diseases and/or conditions such as a Picornavirus and/or Flaviviridae infection with one or more nucleosides, nucleotides and nucleotide analogs.

The present invention relates to compounds of the formula I: ##STR00001##
including any possible stereoisomers thereof, wherein R.sup.9 has the meaning as defined herein, or a pharmaceutically acceptable salt or solvate thereof. The present invention also relates to processes for preparing said compounds, pharmaceutical compositions containing them and their use, alone or in combination with other HCV inhibitors, in HCV therapy.

The present invention relates to compounds of the formula I: ##STR00001##
including any possible stereoisomers thereof, wherein R.sup.9 has the meaning as defined herein, or a pharmaceutically acceptable salt or solvate thereof. The present invention also relates to processes for preparing said compounds, pharmaceutical compositions containing them and their use, alone or in combination with other HCV inhibitors, in HCV therapy.

The invention provides compounds of the formula: ##STR00001##
wherein B is a nucleobase selected from the groups (a) to (d): ##STR00002##
and the other variables are as defined in the claims,
which are of use in the treatment or prophylaxis of hepatitis C virus infection, and related aspects.

Some embodiments of the present invention include nucleoside 5-monophosphate derivative compounds, their preparation and their uses. In some embodiments, such compounds are useful to treat hepatitis C viral infections.

Some embodiments of the present invention include nucleoside 5-monophosphate derivative compounds, their preparation and their uses. In some embodiments, such compounds are useful to treat hepatitis C viral infections.

Provided herein are compounds, compositions and methods for the treatment of Flaviviridae infections, including HCV infections. In certain embodiments, compounds and compositions of nucleoside derivatives are disclosed, which can be administered either alone or in combination with other anti-viral agents. In certain embodiments, the compounds are 2-dichloro or 2-fluoro-2-chloro nucleoside analogue compounds which display remarkable efficacy and bioavailability for the treatment of, for example, HCV infection in a human. In certain embodiments, the compounds are of Formula (I): or a pharmaceutically acceptable salt, solvate, stereoisomeric form, tautomeric form or polymorphic form thereof; wherein each of R.sup.A and R.sup.B is independently Cl or F, wherein at least one of R.sup.A and R.sup.B is Cl; and Base, PD and Z are as described herein.

##STR00001##

Provided are crystalline forms of the compound of formula (I), which is a nucleoside inhibitor of HCV, processes for the preparation thereof, and pharmaceutical compositions comprising these crystalline forms.

##STR00001##

Provided are crystalline forms of the compound of formula (I), which is a nucleoside inhibitor of HCV, processes for the preparation thereof, and pharmaceutical compositions comprising these crystalline forms.

##STR00001##

Some embodiments of the present invention include nucleoside 5-monophosphate derivative compounds, their preparation and their uses. In some embodiments, such compounds are useful to treat hepatitis C viral infections.