One‐Step Synthesis of Novel Erlotinib Analogs Catalyzed by Nano‐CuO as Potent Anticancer Agent

ABSTRACT Twenty new substituted erlotinib analogs with anticancer activity were produced with good to excellent yields through the one‐step reaction of erlotinib, aromatic aldehydes, and cyclic secondary amines such as piperidine, morpholine, pyrrolidine, N ‐methylpiperazine, or imidazole using nano‐CuO in choline chloride: urea (ChCl:urea) solvent under ultrasound irradiation at 80°C. MTT protocol was applied to investigate the cytotoxicity of all produced substituted erlotinib analogs in A431 (human epidermoid carcinoma cell) and HU02 (foreskin fibroblast) cell lines. The results illustrated that at a concentration of less than 10 μM, the growth of A431 cells could be inhibited by the produced compounds. Compared to erlotinib as positive control, the highest cytotoxic activity with IC 50 equal to 2.58 ± 0.57 μM belonged to compound 4c carrying 4‐fluorobenzene with piperidine substitution. All of the synthesized compounds showed significant cytotoxic activity on A431, while showing no apparent cytotoxicity to HU02. The reasons for the stronger cytotoxic activity 4c can be most probably attributed to the two phenomena of greater solubility of the fluoro derivative and the flexibility of piperidine. Based on this study, compound 4c is the most promising compound with anticancer properties.