Sulfonylated 5-piperazine-substituted 1,3-oxazole-4-carbonitriles were synthesized and evaluated for in vitro anticancer activity. Cytotoxicity was assessed in hepatocellular (HepG2, Huh7), breast (MCF-7, MDA-MB-231), cervical (HeLa), melanoma (M21), and neuroblastoma (Kelly, SH-SY5Y) cell lines, with HEK293 cells used as a non-malignant control. Compounds 7a, 7b, and 8aa emerged as lead structures. Notably, compound 7b showed the highest activity in Kelly neuroblastoma cells (IC₅₀ = 1.3 µM) while exhibiting low cytotoxicity toward HEK293 cells (IC₅₀ > 10 µM), indicating an improved selectivity profile relative to doxorubicin. In silico molecular docking suggested favorable interactions of the lead compounds with several cancer-associated proteins, with the highest predicted affinity observed for Aurora A kinase, along with additional predicted interactions with cyclin-dependent kinases. Predicted ADMET properties of compounds 7a, 7b, and 8aa compared favorably with doxorubicin, although the lead compounds were not readily biodegradable under OECD 301D conditions. Overall, these findings identify oxazole-4-carbonitriles as promising anticancer candidates with a putative kinase-directed mechanism of action.

Neuroblastoma, a leading cause of pediatric cancer mortality, requires efficient and selective therapeutics. We synthesized and characterized a series of sulfonated 5-piperazine-containing 1,3-oxazole-4-carbonitrile derivatives via sulfonylation protocols and evaluated their in vitro cytotoxicity against human hepatocellular carcinoma (HepG2, Huh7), breast (MCF7, MDA-MB-231), cervical (HeLa), melanoma (M21), and two neuroblastoma (Kelly, SHSY5Y) cell lines, alongside non-malignant HEK293 cells. Three compounds (7a, 7b, and 8aa) demonstrated efficient and selective cytotoxicity toward MYCN-amplified (Kelly) and MYCN-non-amplified (SHSY5Y) neuroblastoma cells, with 7b being the most active (IC₅₀ = 1.9 µM in Kelly cells) and showing minimal toxicity in HEK293 (IC₅₀ > 10 µM). In Kelly cells, 7b matched doxorubicin while showing lower off-target toxicity and low-micromolar activity in solid tumors. The hit compounds were shown to be not readily biodegradable under OECD 301D test. In silico docking revealed high-affinity binding to the ATP-binding site of Aurora A kinase in the Aurora A/N-MYC complex (ΔG = –10.8 to –10.9 kcal/mol). Compound 7b exhibited broad cytotoxicity across all tested cancers (IC₅₀ = 1.5–4.0 µM). ADMET profiling of 7a, 7b, and 8aa indicated favorable pharmacokinetic and toxicity parameters compared with doxorubicin. These findings identify sulfonylated oxazole-4-carbonitriles as neuroblastoma therapeutics with potential use against proliferating malignancies.