Some parent-progeny suggestions are obvious, e.g., the antiviral progenies very similar to the Emtricitabine parent in the upper-left "spider" in Figure . Focusing on less trivial pairs, we note an Azuvidine parent in Figure and Ribavirin parent found in both Figures and. Among Azuvidine's progenies, Mizoribine immunosuppressant and Pidotimod immunomodulator stand out because of their relevant indications and because their 3D conformations show good overlap with Azuvidine (Figures ). Rivabirin also gives Mizoribine progeny and, additionally, Diphylline antiasthmatic, Inosine antinflammatory, and Thioinosine immunosuppressant, all of which show significant 3D parent-progeny overlap (Figures ). The variety of these primary indications reflects different roles nucleotides and their derivatives play in processes ranging from signaling ), to the inhibition of viral replication (e.g., Ribavirin ), to immunosuppression (e.g., Mizoribine inhibits inosine and guanosine monophosphate synthetases ). Although detailed structural knowledge of SARS-CoV-2 proteins involved in viral replication is lacking, we do not find it inconceivable that some of the closely-shaped nucleotide-based immunosuppressants/immunomodulators might also show activity against viral replication.