Regioselective oxidation of indoles to 2-oxindoles was written by Shelar, Santosh V.;Argade, Narshinha P.. And the article was included in Organic & Biomolecular Chemistry in 2019.Name: 2-(2-Oxoindolin-3-yl)acetic acid This article mentions the following:
Facile regioselective oxidation of indoles to 2-oxindoles I [R = H, CH2CO2H, CH2CO2Me, etc.] promoted by sulfuric acid adsorbed on silica gel was reported. The demonstrated practical site-selective heterogeneous oxidation reactions conveniently took place with a broad substrate scope and functional group tolerances. The present oxidation strategy was also employed to accomplish the total synthesis of natural products donaxaridine and donaxarine. On the basis of anal. and spectral data it was evidenced that donaxarine stayed in equilibrium with its hydrated ring opened form. The structural features essential for this type of oxidation and plausible mechanism were discussed in brief. In the experiment, the researchers used many compounds, for example, 2-(2-Oxoindolin-3-yl)acetic acid (cas: 2971-31-5Name: 2-(2-Oxoindolin-3-yl)acetic acid).
2-(2-Oxoindolin-3-yl)acetic acid (cas: 2971-31-5) belongs to indole derivatives. Indole, also called Benzopyrrole, a heterocyclic organic compound occurring in some flower oils, such as jasmine and orange blossom, in coal tar, and in fecal matter. They are capable of binding to a variety of receptors with high affinity and thus have applications in a wide range of therapeutic areas.Name: 2-(2-Oxoindolin-3-yl)acetic acid
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Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles