“…Many other lactones have antitumor activities, including alantolactone which shows almost similar activities against many tumors as ISA ( Liu X. et al, 2021 ; Wang, 2021 ). Many derivatives of ISA have been synthesize and their antitumor effects were tested in various kinds of tumors ( Anikina et al, 2018 ; Kumar et al, 2016 ; Mo et al, 2024 ; Semakov et al, 2018 ). Among these derivatives, the most potent one is a hybrid of ISA/hydroxamic acid, ((3αR,4αR,6R,8αR, 9αR)-8α-methyl-3,5-dimethylene-2-oxododecahydronaphtho [2,3-b]furan-6-yl (4-((E)-3-(hydroxyamino)-3-oxoprop-1-en-1-yl) benzoyl)- R -alaninate) (Derivative 11, Figure 2K ), the IC 50 of which against the cancer cell lines were below 0.3 μM ( Mo et al, 2024 ).…”