TH6342 is a SAMHD1 modulator that binds to pretetrameric SAMHD1 and prevents its oligomerization and allosteric activation. SAMHD1 is a dNTP triphosphohydrolase and an HIV-1 restriction factor. SAMHD1 can limit the replication of retroviruses and DNA viruses and has antiviral effects. The inhibitory mechanism of TH6342 does not occupy the SAMHD1 nucleotide-binding pocket, gently binds the target, and functions as a chemical probe.