C-171 is an inhibitor of stimulator of interferon genes (STING).?It binds to STING, inhibits its palmitoylation, and prevents the recruitment and phosphorylation of TBK1.

STING agonist-30 is a potent activator of STING-dependent immune responses, demonstrating broad-spectrum antiviral effects against viruses such as HSV (Herpes Simplex Virus), rotavirus, and SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2).

STING activator Compound 53 based on an oxindole core structure demonstrated robust on-target functional activation of STING (human EC50 185 nM) in immortalised and primary cells and a cytokine induction fingerprint consistent with STING activation.