{Reference Type}: Journal Article
{Title}: Design, synthesis, pharmacological evaluation, and computational study of benzo[d] isothiazol-based small molecule inhibitors targeting PD-1/PD-l1 interaction.
{Author}: Wang H;Shen L;Chen L;Gao Y;Ma L;Lian W;Zhang Z;Liu H;Yang H;Wang J;Zhao D;Cheng M;
{Journal}: Eur J Med Chem
{Volume}: 275
{Issue}: 0
{Year}: 2024 Sep 5
{Factor}: 7.088
{DOI}: 10.1016/j.ejmech.2024.116622
{Abstract}: Blockade of the programmed cell death-1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway is an attractive strategy for immunotherapy, but the clinical application of small molecule PD-1/PD-L1 inhibitors remains unclear. In this work, based on BMS-202 and our previous work YLW-106, a series of compounds with benzo[d]isothiazol structure as scaffold were designed and synthesized. Their inhibitory activity against PD-1/PD-L1 interaction was evaluated by a homogeneous time-resolved fluorescence (HTRF) assay. Among them, LLW-018 (27c) exhibited the most potent inhibitory activity with an IC50 value of 2.61 nM. The cellular level assays demonstrated that LLW-018 exhibited low cytotoxicity against Jurkat T and MDA-MB-231. Further cell-based PD-1/PD-L1 blockade bioassays based on PD-1 NFAT-Luc Jurkat cells and PD-L1 TCR Activator CHO cells indicated that LLW-018 could interrupt PD-1/PD-L1 interaction with an IC50 value of 0.88 μM. Multi-computational methods, including molecular docking, molecular dynamics, MM/GBSA, MM/PBSA, Metadynamics, and QM/MM MD were utilized on PD-L1 dimer complexes, which revealed the binding modes and dissociation process of LLW-018 and C2-symmetric small molecule inhibitor LCH1307. These results suggested that LLW-018 exhibited promising potency as a PD-1/PD-L1 inhibitor for further investigation.