To provide a chiral reagent or a salt thereof. The chiral reagent has following chemical formula (I). In the formula (I), G.sup.1 and G.sup.2 are independently a hydrogen atom, a nitro group (NO.sub.2), a halogen atom, a cyano group (CN), a group of formula (II) or (III), or both G.sup.1 and G.sup.2 taken together to form a group of formula (IV). ##STR00001##

The invention features a mononucleotide comprising a nucleobase bonded to a sugar having a 3-carbon and a 5-carbon, where the 5-carbon is bonded to a phosphorus (V) atom of a phosphate group through an oxygen atom, the phosphorus (V) atom being bonded to (i) a disulfide bioreversible group through an oxygen atom; and (ii) (a) optionally substituted amino, optionally substituted alkoxy, optionally substituted aryloxy, or optionally substituted heteroaryloxy; or (b) the 3-carbon through an oxygen atom. The invention also features methods of delivering the mononucleotide to a cell and methods of treating a subject having Hepatitis C.

The present invention provides nucleosides and oligonucleotides comprising a 5 phosphate mimics of formula (IVc) or (Vc), ##STR00001##
One aspect of the present invention relates to modified nucleosides and oligonucleotides comprising such dinucleotide of formula (Ia). Another aspect of the invention relates to a method of inhibiting the expression of a gene in call, the method comprising (a) contacting an oligonucleotide of the invention with the cell; and (b) maintaining the cell from step (a) for a time sufficient to obtain degradation of the mRNA of the target gene.

The present invention provides nucleosides and oligonucleotides comprising a 5 phosphate mimics of formula (IVc) or (Vc), ##STR00001##
One aspect of the present invention relates to modified nucleosides and oligonucleotides comprising such dinucleotide of formula (Ia). Another aspect of the invention relates to a method of inhibiting the expression of a gene in call, the method comprising (a) contacting an oligonucleotide of the invention with the cell; and (b) maintaining the cell from step (a) for a time sufficient to obtain degradation of the mRNA of the target gene.

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.

The present invention relates to novel phosphorous (V) (P(V)) reagents, methods for preparing thereof, and methods for preparing organophosphorous (V) compounds by using the novel reagents.

Provided herein am phosphoramidate and cyclophosphate prodrug compounds of unnatural configuration nucleotide, their preparation, and their uses, such as treating liver diseases or nonliver diseases via intervening in the molecular pathways in the liver.

Provided herein am phosphoramidate and cyclophosphate prodrug compounds of unnatural configuration nucleotide, their preparation, and their uses, such as treating liver diseases or nonliver diseases via intervening in the molecular pathways in the liver.