ANTIVIRAL AGENTS

The invention relates to a method for the treatment and/or prophylaxis of a Hepadnaviridae associated infection which comprises administration of an effective amount of a compound of Formula (1), wherein R1 is hydrogen, halogen, hydroxy, azide, optionally substituted alkyl, optionally substituted alkoxy, optionally substituted aryloxy, mercapto, optionally substituted alkylthio, optionally substituted amino, optionally substituted hydrazino or optionally substituted hydroxylamino; R2 is hydrogen, halogen, hydroxy, azide, optionally substituted alkoxy, optionally substituted aryloxy, mercapto, optionally substituted alkylthio or optionally substituted amino; R3 and R3' are the same or different and selected from hydrogen, optionally substituted alkyl, halogen, hydroxy, azide, optionally substituted alkoxy, optionally substituted aryloxy, mercapto, optionally substituted thio and optionally substituted amino; or R3 and R3' together form =O, =S, =NOH or =NOR, wherein R is optionally substituted alkyl; and R4, R5 and R6 are the same or different and selected from optionally substituted alkyl, optionally substituted aralkyl, halogen, hydroxy, azide, optionally substituted alkoxy, optionally substituted aryloxy, mercapto, optionally substituted alkylthio, optionally substituted amino, optionally substituted acyl, optionally substituted ester, cyano, carboxy and mono-, di- or tri- phosphate; two of R4, R5 and R6 are joined together to form a cyclic group; or R4, R5 and R6 are joined together to form a cyclic ortho ester group, salts thereof, pharmaceutically acceptable derivatives thereof, pro-drugs thereof, tautomers thereof and/or isomers thereof to a subject requiring said treatment and/or prophylaxis. The invention also relates to novel compounds of Formula (1), processes for their preparation and pharmaceutical or veterinary compositions containing them. Procédé de traitement et/ou de prévention d'une infection associée aux Hepadnaviridae. Ce procédé consiste à administrer une dose efficace, à un sujet nécessitant ledit traitement et/ou ladite prévention, d'un composé répondant à la formule (1), dans laquelle R1 représente hydrogène, halogène, hydroxy, azide, alkyle éventuellement substitué, alcoxy éventuellement substitué, aryloxy éventuellement substitué, mercapto, alkylthio éventuellement substitué, amino éventuellement substitué, hydrazino éventuellement substitué ou hydroxylamino éventuellement substitué; R2 représente hydrogène, halogène, hydroxy, azid