The present invention relates to a prodrug of tenofovir and medical use thereof. Specifically, the present invention relates to compound with a formula (I), or isomer, pharmaceutically acceptable salt, hydrate or solvate thereof, and its use in the treatment of viral infectious diseases, especially AIDS (HIV) infection, hepatitis B and hepatitis B virus-induced diseases, wherein the respective substituents of formula (I) are as those defined in the specification.本發明涉及一種替諾福韋前藥及其在醫藥上的應用。具體而言，本發明涉及一種如通式(I)所示的化合物或其異構體、可藥用鹽、水合物或溶劑化物，以及它們在製備治療病毒感染性疾病特別是愛滋病(HIV)感染、乙型肝炎和乙肝病毒引起的疾病的藥物中的應用，其中通式(I)中的各取代基的定義與說明書中的定義相同。
