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Fig.6. Confocal laser scanning microscopic images of HepG2 cells treated
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Cell images in bright field. b) Fluorescence images of cells stained with 12. c)
Fluorescence images of cells stained with Rh123. d) Merged images of a and b.
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MDA-MB231
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In summary, a series of sterol 5α,8α-endoperoxide derivatives
were synthesized and evaluated for their anticancer activities.
Some of the synthesized compounds exhibited good anticancer
activities against the four tested cancer cell lines in vitro. In
particular, compound 9d, 9f, 9h, 9j and 9m were the most
promising derivatives, with IC50 values ranging from 9.3-20 µM,
against all the four cancer cell lines respectively. Substituent
changes to the C-17 position can affect potency against different
kinds of cancer cell lines. Fluorescence images showed that the
designed coumarin-9d (12) conjugate localized mainly in
mitochondria, leading to enhanced anticancer activities over 9d.
Future work will focus on the synthesis of additional candidate
structures with different side chains to address specific cancer
cell lines. It appeared that substituent changes to the C-17
position could serve as a promising launch point for further
design of this type of steroidal anticancer agents.
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Supplementary Material
Supplementary data associated with this article can be found,
in the online version, at
Acknowledgments
The authors would like to acknowledge financial support from
the Chinese Natural Science Foundation Project (21272020), and
Beijing Key Laboratory for Green Catalysis and Separation.
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