Abstract
Spirochromanes incorporating Schiff's bases and semicarbazones 4a-e and 5a-j were synthesizedand analyzed for their potential antiproliferative activity using four human cancer cell lines (MCF-7, HCT-116, PC3, and A549). Compounds 5a, 5b and 5g possessed the highest antiproliferative activity among the tested compounds,with an IC(50) range of 1.154-9.09 μM. Compound 5j selectively inhibited the PC3 cell proliferation (IC(50) = 5.47 μM). Spirochromanes 5a, 5b and 5g exhibited high inhibitory activity against EGFR (IC(50) = 0.116, 0.132, and 0.077 μM, respectively) and HER2 (IC(50) = 0.055, 0.210 and 0.085 μM, respectively) compared with the references, erlotinib (IC(50) = 0.090 and 0.038 μM, respectively) and gefitinib (IC(50) = 0.052 and 0.072 μM, respectively). Cell cycle analysis and apoptosis results showed that compounds 5a, 5b and 5g arrested growth inthe S phase, and the programmed cell death induced by these compounds was an apoptotic mechanism rather than a necrotic pathway. Molecular docking studies of spirochromanes 5a, 5b and 5g to EGFR and HER2 binding sites were performed to explore the orientation mode and interaction.