Abstract: Background: Alkynes are fundamental building blocks in synthetic chemistry with high
pharmaceutical applications. Among the bioactive acetylenic molecules, propargylic alcohol is most important
as almost all the marketed drugs contains quaternary centered propargylic alcohol functionality.
Objective: In this study we have synthesised and evaluated 3-hydroxy-3-ethynylindolin-2-one derivatives for in
vitro cytotoxic activity.
Method: An expeditious method for direct alkynylation of isatins (ketones) has been developed using tetrabutylammonium
fluoride (TBAF) as a catalyst in THF solvent at room temperature under metal-free conditions.
Furthermore, this method is an economically viable process that also compliments green aspects like being a
ligand/metal free process under ambient conditions. This reaction tolerated a wide range of substrates with good
to excellent yields (80-94%).
Results: The results showed that the synthesized compounds (4m, 4n and 4p) has the ability to inhibit Akt
kinase activity with IC50 values ranging from 7.7 to 9.8 µM.
Conclusion: All the 3-hydroxy-3-ethynylindolin-2-one derivatives were subjected for in vitro cytotoxic activity
on five different cancer cell lines. Further, the synthesized compounds (4m, 4n and 4p) were evaluated for their
ability to inhibit Akt kinase activity and exhibited good inhibition with IC50 values ranging from 7.7 to 9.8 µM..