Direct Catalytic Asymmetric Synthesis of Oxindole-Derived δ-Hydroxy-β-ketoesters by Aldol Reactions was written by Zhang, Dongxin;Chen, Yan;Cai, Hu;Yin, Lei;Zhong, Junchao;Man, Jingjing;Zhang, Qian-Feng;Bethi, Venkati;Tanaka, Fujie. And the article was included in Organic Letters in 2020.Category: indole-building-block This article mentions the following:
Direct asym. synthesis of δ-hydroxy-β-ketoesters was accomplished via regio- and enantioselective aldol reactions of β-ketoesters with isatins catalyzed by cinchona alkaloid thiourea derivatives The C-C bond formation of the reactions occurred only at the γ-position of the β-ketoesters. Reaction progress monitoring and product stability analyses under the conditions that included the catalyst indicated that the γ-position reaction products were formed kinetically. Various δ-hydroxy-β-ketoesters bearing 3-alkyl-3-hydroxyoxindole cores relevant to the development of bioactive mols. were synthesized. In the experiment, the researchers used many compounds, for example, 5,6-Difluoroindoline-2,3-dione (cas: 774-47-0Category: indole-building-block).
5,6-Difluoroindoline-2,3-dione (cas: 774-47-0) belongs to indole derivatives. Indole could be stereoselectively alkylated with chiral cyclopentyl sulfone reagent. Indole plays a fundamental role for QS in E. coli, being one of the signal molecules responsible for the transcription of a variety of genes (gabT, and tnaB ASTD). Category: indole-building-block
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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