Described herein are cyclopentyl nucleoside analogs of Formula (I), pharmaceutical compositions that include one or more cyclopentyl nucleoside analogs and methods of using the same to treat HBV, HDV and/or HIV. (I)

##STR00001##

Methods for preparation of 2′,3′-dideoxynucleotides support structures, such as 2′,3′-dideoxyguanosine, 2′,3′-dideoxyadenosine, and 3′-deoxythymidine support structures are disclosed. Various methods of using such structures are also provided, such as their use for automated DNA synthesis and pyrophosphorolysis activated polymerization.

Methods for preparation of 2′,3′-dideoxynucleotides support structures, such as 2′,3′-dideoxyguanosine, 2′,3′-dideoxyadenosine, and 3′-deoxythymidine support structures are disclosed. Various methods of using such structures are also provided, such as their use for automated DNA synthesis and pyrophosphorolysis activated polymerization.

This disclosure is directed to: (a) processes for preparing compounds and salts thereof that, inter alia, are useful for inhibiting hepatitis C virus (HCV); (b) intermediates useful for the preparation of the compounds and salts; (c) pharmaceutical compositions comprising the compounds or salts; and (d) methods of use of such compositions.

This disclosure is directed to: (a) processes for preparing compounds and salts thereof that, inter alia, are useful for inhibiting hepatitis C virus (HCV); (b) intermediates useful for the preparation of the compounds and salts; (c) pharmaceutical compositions comprising the compounds or salts; and (d) methods of use of such compositions.

Provided is an oligonucleic acid analog which contains, as at least one structural unit thereof, a modified nucleic acid monomer compound which is a ring-open nucleoside having a cleaved carbon-carbon bond between the 2′ and 3′ positions and a substituent hydroxymethyl group at the 4′ position. When used as siRNA, the oligonucleic acid analog exhibits superior biological stability and target gene expression inhibiting activity. The oligonucleic acid analog can be used in antisense methods, ribozyme methods, and decoy methods, etc., can be used as a nucleic acid aptamer, and can also be used as a nucleic acid probe or molecular beacon, etc., or in genetic diagnostics, etc.

Provided is an oligonucleic acid analog which contains, as at least one structural unit thereof, a modified nucleic acid monomer compound which is a ring-open nucleoside having a cleaved carbon-carbon bond between the 2′ and 3′ positions and a substituent hydroxymethyl group at the 4′ position. When used as siRNA, the oligonucleic acid analog exhibits superior biological stability and target gene expression inhibiting activity. The oligonucleic acid analog can be used in antisense methods, ribozyme methods, and decoy methods, etc., can be used as a nucleic acid aptamer, and can also be used as a nucleic acid probe or molecular beacon, etc., or in genetic diagnostics, etc.

Described herein are novel divalent nucleobases that each bind two nucleic acid strands, matched or mismatched when incorporated into a nucleic acid or nucleic acid analog backbone (a genetic recognition reagent, or genetic recognition reagent). In one embodiment, the genetic recognition reagent is a peptide nucleic acid (PNA) or gamma PNA (γPNA) oligomer. Uses of the divalent nucleobases and monomers and genetic recognition reagents containing the divalent nucleobases also are provided.

Described herein are novel divalent nucleobases that each bind two nucleic acid strands, matched or mismatched when incorporated into a nucleic acid or nucleic acid analog backbone (a genetic recognition reagent, or genetic recognition reagent). In one embodiment, the genetic recognition reagent is a peptide nucleic acid (PNA) or gamma PNA (γPNA) oligomer. Uses of the divalent nucleobases and monomers and genetic recognition reagents containing the divalent nucleobases also are provided.

Compounds of Formula I: ##STR00001##
are HIV reverse transcriptase inhibitors, wherein R.sup.1, R.sup.2, R.sup.E, L, M and Z are defined herein. The compounds of Formula I and their pharmaceutically acceptable salts are useful in the inhibition of HIV reverse transcriptase, the prophylaxis and treatment of infection by HIV and in the prophylaxis, delay in the onset or progression, and treatment of AIDS. The compounds and their salts can be employed as ingredients in pharmaceutical compositions, optionally in combination with other antivirals, immunomodulators, antibiotics or vaccines.