Design, Synthesis, and Biological Evaluation of Novel Bis‐Phthalimides Targeting LANA of Kaposi's Sarcoma‐Associated Herpesvirus

ABSTRACT Kaposi's sarcoma‐associated herpesvirus (KSHV) is a major oncogenic pathogen, largely due to its Latency‐Associated Nuclear Antigen (LANA), which sustains viral latency and drives tumor development. Inhibiting LANA has emerged as a promising therapeutic approach for KSHV‐related cancers. This study focuses on the design, synthesis, and evaluation of novel bis‐phthalimide cytotoxic derivatives as potential LANA inhibitors. A series of derivatives was prepared, structurally characterized, and subjected to computational analyses, including ADME profiling, molecular docking, and molecular dynamics simulations to assess their stability and binding interactions with LANA. Their cytotoxic activity was tested against A549 and HEp‐2 cancer cell lines using MTT assays. Docking studies revealed strong affinities, with compounds AG 38 and AG 43 showing binding energies of −11.4 and −10.2 kcal/mol. ADMET predictions indicated favorable pharmacokinetics. In vitro assays demonstrated dose‐dependent antiproliferative effects, surpassing lenalidomide. Notably, AG 34 and AG 39 exhibited potent activity, with CTC 50 values of 120 ± 9.4 µg/mL against A549 and 135 ± 9.9 µg/mL against HEp‐2. Interestingly, analogues with bulky or branched linkers showed reduced activity, while aromatic linkers, though less cytotoxic, displayed enhanced stability in silico. Overall, these findings highlight bis‐phthalimide derivatives as promising candidates for further optimization against KSHV‐associated malignancies.