Autocatalytic synthesis of 3-ethyl-3-hydroxy-indole-2-ones and their neuroprotection and antitumor activities' evaluation

In this study, a series of 3-ethyl-3-hydroxy-indole-2-ones were synthesized through the addition reaction of Et₂Zn and N-substituted isatin by an autocatalytic process. The synthesized compounds were characterized by NMR spectroscopy and mass spectrometry, and the reaction mechanism was discussed. The antitumor and neuroprotection activities of these compounds were evaluated. The results showed that several compounds display protection activity on H₂O₂-induced apoptosis of PC12 cells, which are more effective than that of (±)-α-tocopherol Vitamin E (VE). Moreover, these compounds also show antitumor activity against A549 and P388 cell lines.