NUCLEOSIDE ANALOG

a compound (e.g., AZT, ddI, ddC, d4T, 3TC) that mimics one of the building blocks of DNA and RNA. These compounds suppress retroviral replication by interfering with the reverse transcriptase enzyme. The defective synthetic nucleosides cause premature termination of the viral DNA chain. Nucleoside analogs are prodrugs that are converted into active agents by phosphorylation.