Exploring 4-morpholinopyrrolo-[2,3-d]-pyrimidine derivatives as novel anti-cancer agents: Design, synthesis and biological studies

Despite extensive research efforts, cancer continues to pose a significant global health challenge. Continuing the anti-cancer research, twenty-four 4-Morpholinopyrrolo-[2,3-d]-pyrimidine derivatives were synthesized and characterized via HRMS, 1H, 13C NMR, and FTIR. A single crystal for one compound, PGT4, was developed for further confirmation. All synthesized compounds were assessed for their anti-cancer activity in three cancer cell lines, SCC-25 (oral squamous cell carcinoma), U87-MG (glioblastoma) and MCF-7 (breast cancer) and one normal cell line HEK-293T (human embryonic kidney) using WST assay. Fourteen compounds demonstrated IC50 values ranging from 2 to 10 mu M against the SCC-25 cell line. PTT3 and PGT7 were the most effective compounds against the SCC-25 cell line, showing an IC50 of 2 mu M. Cell cycle analysis was also performed using propidium iodide staining, and apoptosis studies were carried out using caspase 3/7 activity assay and Annexin V-FITC isothiocyanate assay. PTT3 and PGT7 arrested the cell cycle at the G1 phase and enhanced the apoptosis by 9.1 and 13.8-folds in SCC-25 cells, respectively. Treatment with PTT3 and PGT7 also resulted in a dose-dependent decrease in the colony formation of SCC-25 cells. We carried out the molecular docking and dynamic studies to find the insights on binding mechanisms of PTT3 and PGT7 within the active region of the PI3K gamma target protein (PDB ID: 3IBE, 2.80 & Aring;). Additionally, in-silico ADME properties were predicted for the most active molecules, PTT3 and PGT7, aiding in assessing their pharmacokinetic profiles.