ANTI-VIRAL PYRIMIDINE NUCLEOSIDE DERIVATIVES

摘要

A compound for use in the treatment or prophylaxis of viral infections such, for example as chicken pox or shingles caused by the Varicella Zoster virus, said compound having the general formula (II): wherein X is O, S, NH or CH₂, Y is O, S or NH, Z is O, S or CH₂, R₁ is C_1-6 alkyl, preferably n-alkyl, e.g., n-pentyl or n-hexyl, and one of R₂ and R₃ is OH, and the other of R₃ and R₂ is a neutral, non-polar amino acid moiety, or a pharmaceutically acceptable salt or hydrate thereof. Said neutral, non-polar amino acid moiety R₂ or R₃ may be (IV): in which R₄, R₅, R₆ and R₇ are each independently H or C _1-2 alkyl. In preferred embodiments, one of R₂ or R₃ is valine, leucine, isoleucine or alanine, particularly valine.