Synthesis and Cytotoxic Activities of Novel Ether Conjugates of Dihydroartemisinin and Zerumbone: Evidenced by Intergrating Network Pharmacology and In Vitro Assay.

O-alkylation of the hydroxy compounds, including acetaminophen, starting compounds for the synthesis of the drug, and natural compounds with the bromides of dihydroartemisinin (DHA) and zerumbone, produced twenty novel ether conjugates 15a-j and 16a-j, respectively. Their structures were elucidated by 1D-, 2D-NMR, and HRMS data. Their in vitro cytotoxic activity was screened using three cancer cell lines: HepG2, HeLa, and PC-12. The results showed that eight out of ten conjugates in series 15a-j containing DHA skeleton exhibited activity against the tested cell lines, with IC50 values ranging from 4.26-47.37 µM. Notably, all conjugates in series 16a-j containing zerumbone scaffolds inhibited the growth of HepG2, HeLa, and PC12 with IC50 in the range of 4.46-35.07 µM. Using network pharmacology and molecular docking to target anti-liver cancer in the above 20 synthetic compounds, 271 intersection targets were discovered, including 5 targets with high degree values (EGFR, ESR1, AKT1, MDM2, and NFKB1). Artemisinin derivative 15i gave the highest binding energy for targets AKT1, EGFR, and NFKB1, while zerumbone-murrayafoline A ether 16g in the remaining series also gave the highest energy for proteins EGFR, AKT1, and NFKB1.