Exploring the anticancer properties of indole pyrimidine derivatives: Synthesis, structural insights, docking analysis, and in vitro evaluation

The nitrogen containing heterocyclic and chalcones moiety widely recognized as favorable combination of diagnostic and therapeutic facilities in medicinal chemistry. In particular, indole analogs play a very important medicinal role in pharmacology activities, hence, drugs like pindolol, indomethacin, oxypertine, ellipticine, arbidol and ate viridine are well known in market. In this view, the title compounds 4(a-j) were synthesized in good yield. The purified compounds were explained by spectroscopic procedures (FT-IR, 1H NMR, 13CNMR, and LC-MS), and lastly, all synthetic compounds have in-vitro efficacy assessed against the HeLa human cervical cancer and MCF-7 human breast cancer cell lines, and their efficacy was compared to that of the well-known anticancer drug methotrexate (Methotrexate). Compounds 4a, 4b, 4c, and 4e from the series (4a-j) demonstrated the most notable inhibitory activity. The cytotoxicity evaluation of these newly synthesized compounds revealed that 4a, 4b, 4c, and 4e were the most toxic to HeLa cells, with IC50 values for growth inhibition of 20.41 ± 3.14, 23.54 ± 3.27, 24.77 ± 2.14, and 26.10 ± 1.58, respectively. These compounds exhibited an even stronger growth-inhibitory effect on MCF-7 cells, with IC₅₀ values of 18.84 ± 2.69, 19.45 ± 3.14, 22.83 ± 2.68, and 21.80 ± 1.68, respectively. In comparison, methotrexate (Methotrexate) showed IC50 values of 28.29 ± 1.0 for HeLa cells and 45.08 ± 2.61 for MCF-7 cells. Additionally, compounds 4a, 4b, 4c, and 4e played a crucial role in interacting with the catalytic domain of PDE3, demonstrating IC₅₀ values for PDE3A inhibition of 8.05 ± 1.27, 7.55 ± 2.14, 15.09 ± 1.54, and 17.12 ± 3.14, respectively. These results are compared with Cilostazol, a known PDE inhibitor, which exhibited an IC50 of 0.00368 ± 3.14. In-silico studies revealed that compounds (4a, 4b, and 4c) are comparatively very efficient in binding with PDE3A which was further validated with MMGBSA and MDSs.