Palladium-Catalyzed Synthesis and Anticancer Activity of Paclitaxel–Dehydroepiandrosterone Hybrids

[Image: see text] According to the activity–structure relationship of the C-13 side chain in paclitaxel or docetaxel, eighteen novel paclitaxel–dehydroepiandrosterone (DHEA) hybrids were designed and synthesized by Pd(II)-catalyzed Suzuki–Miyaura cross-coupling of 17-trifluoromethanesulfonic enolate-DHEA with different aryl boronic acids. The in vitro anticancer activity of the hybrids against a human liver cancer cell line (HepG-2) was evaluated by MTT assay, showing that most of these hybrids possessed moderate antiproliferative activity against the HepG-2 cancer cell line. Among these hybrids, three ones (7b, 7g, and 7i) with ortho-substituents in the phenyl group of the D-ring of DHEA analogues exhibited moderate anticancer activity. The optimal compound 7i showed superior anticancer activity against the HepG-2 cell line with an IC(50) value of 26.39 μM.