The present invention is directed to a method and composition of treating or preventing viral infections, in particular, human immunodeficiency virus (HIV) and hepatitis B virus (HBV) infections, in human patients or other animal hosts, comprising the administration of N.sup.4-acyl-2′,3′-dideoxy-5-fluorocytidine or N.sup.4-acyl-2′,3′-didehyd-ro-2′,3′-dideoxy-5-fluorocytidine, and pharmaceutically acceptable salts, prodrugs, and other derivatives thereof.
1. A compound of formula (II):
or a pharmaceutically acceptable salt thereof, wherein
X is S, NR 5 , CH 2 , CHF or CF 2 ;
R 1 is chosen from halogen, alkyl, haloalkyl, alkenyl, haloalkenyl, alkynyl, haloalkynyl, cycloalkyl, CN, CF 3 , N 3 , NO 2 , aryl, heteroaryl and acyl;
R 2 is chosen from alkenyl, alkynyl, cycloalkyl, aminoalkyl, hydroxyalkyl, haloalkyl, thioalkyl, heteroaryl, and C 6 H 4 R 6 where R 6 is chosen from halogen, CN, CF 3 , N 3 , alkyl, haloalkyl, aminoalkyl, alkoxy, thioalkyl, alkenyl, alkynyl, and aryl;
R 3 and R 3′ are chosen independently from H, halogen, CN, CF 3 , N 3 , NO 2 , alkyl, alkenyl, and alkynyl;
R 4 is H, phosphate, carbonyl substituted with alkyl, alkenyl, alkynyl, or aryl; and
R 5 is H, acyl, alkyl, alkenyl, alkynyl, or cycloalkyl.
2. A pharmaceutical composition that comprises an effective HIV or HBV treatment amount of a compound of claim 1 in a pharmaceutically acceptable carrier or diluent.
3. A method for the treatment of a host infected with HIV that comprises administering an effective amount of a compound of claim 1 in a pharmaceutically acceptable carrier.
4. A method for the treatment of a host infected with HBV that comprises administering an effective amount of a compound of claim 1 in a pharmaceutically acceptable carrier.
5. A method for the treatment of a host infected with HIV that comprises administering an effective amount of a compound of claim 1 in a pharmaceutically acceptable carrier in combination with another anti-HIV agent.
6. A method for the treatment of a host infected with HBV that comprises administering an effective amount of a compound of claim 1 in a pharmaceutically acceptable carrier in combination with another anti-HBV agent.
7. The compound of claim 1 wherein R 3 is H or fluorine and R 3′ is H.
8. The method of claim 3 , wherein R 3 is H or fluorine and R 3′ is H.
9. The method of claim 4 wherein R 3 is H or fluorine and R 3′ is H.