Lewis-Acid-Catalysed Reaction of 3-Hydroxy-2-oxindoles with Terminal Alkynes: Synthetic Approaches to the Pyrroloindoline Alkaloids
作者:Lakshmana K. Kinthada、K. Naresh Babu、Dikshaa Padhi、Alakesh Bisai
DOI:10.1002/ejoc.201700507
日期:2017.6.8
quaternary centre. On further extension of this method, a variety of spiro-2-oxindoles have been synthesized in high yields. The aforementioned methodology has been used in addressing the cyclotryptamine alkaloids linked with aryl group at the pseudobenzylic position.
Lewis Acid-Catalyzed Malonate Addition onto 3-Hydroxy-2-oxindoles: Mechanistic Consideration and Synthetic Approaches to the Pyrroloindoline Alkaloids
作者:K. Naresh Babu、Nikhil Raj Kariyandi、Saina Saheeda M. K.、Lakshmana K. Kinthada、Alakesh Bisai
DOI:10.1021/acs.joc.8b02017
日期:2018.10.19
Metal triflate-catalyzed reactions of 3-hydroxy-2-oxindoles with a variety of malonates have been developed under mild conditions. The reaction afford a variety of 2-oxindoles sharing a C-3 quaternary center at the pseudobenzylic position in an operationally simple procedure. Control experiments using enantioenriched 3-hydroxy/methoxy 2-oxindoles (91% ee) afforded a malonate addition product in racemic
ASYMMETRIC SYNTHESES FOR SPIRO-OXINDOLE COMPOUNDS USEFUL AS THERAPEUTIC AGENTS
申请人:XENON PHARMACEUTICALS INC.
公开号:US20130274483A1
公开(公告)日:2013-10-17
This invention is directed to asymmetric syntheses of certain spiro-oxindole derivatives, which are useful for the treatment and/or prevention of sodium channel-mediated diseases or conditions, such as pain.
FeCl<sub>3</sub>-Promoted Annulation of 2-Haloindoles: Switchable Synthesis of Spirooxindole-chromeno[2,3-<i>b</i>]indoles and Spirooxindole-chromeno[3,2-<i>b</i>]indoles
Electrophilic indoles bearing a leaving group at C2 undergo C3-regioselective dearomative hydroaryloxylation and subsequent 1,2-tertiary alkyl migration/aromatization. This is the first ring-opening migration of the spiroindolenine intermediate formed by the C3 nucleophilic addition reaction. Various spiro-oxindole-chromeno[3,2-b]/[2,3-b]indoles were successfully synthesized in excellent yields (up
The oxindole-embedded ortho-quinone methides were employed as reactive intermediates in formal [4 + 2] annulation with 1,3-dicarbonyls, providing an efficient access to spiro[chromen-4,3'-oxindole] scaffolds via a cascade conjugate addition/ketalization/dehydration process. This protocol featured metal-free conditions, wide substrate scope, and excellent yields.