Stereoselective synthesis and applications of spirocyclic oxindoles

Organic Chemistry Frontiers, Journal Year: 2021, Volume and Issue: 8(5), P. 1026 - 1084

Published: Jan. 1, 2021

This review summaries recent synthetic developments towards spirocyclic oxindoles and applications as valuable medicinal targets.

Language: Английский

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Organocatalytic Synthesis of Chiral Spirooxindoles with Quaternary Stereogenic Centers

European Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 2020(32), P. 5101 - 5118

Published: May 12, 2020

The structure of spirooxindoles is present in a large number natural compounds, with relevant and different biological activities. organic synthesis these compounds has been synthetic challenge due to the fusion two or more cycles one contiguous stereogenic centers. In this review, it described, feasibility organocatalytic asymmetric for achievement chiral through two‐ three‐component reaction presence organocatalyst producing high yield, diastereoselectivity enantiomeric purity. This review covers literature from 2010 2019. most explored reactions purpose have 1,3‐dipolar cycloaddition, Diels‐Alder nucleophilic heterocyclic carbenes reactions, where their mechanisms showed are an approach possible mechanism.

Language: Английский

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DABCO-Catalyzed Michael/Alkylation Cascade Reactions Involving α-Substituted Ammonium Ylides for the Construction of Spirocyclopropyl Oxindoles: Access to the Powerful Chemical Leads against HIV-1

The Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 85(8), P. 5203 - 5219

Published: March 23, 2020

A novel Michael/alkylation cascade reaction of N-unprotected 3-bromooxindoles with α,β-unsaturated acyl phosphonates using DABCO as a robust catalyst followed by the derivatization phosphonate intermediates in situ has been developed. This scenario enables rapid access to diverse set highly functionalized spirocyclopropyl oxindoles moderate yields good excellent diastereoselectivities, which are analogues high active non-nucleoside reverse transcriptase inhibitor against HIV-1. The synthetic potential this tactic highlighted gram-scale and Suzuki cross-coupling reactions product. Moreover, mechanism tentatively elucidated control experiments dynamic high-resolution mass spectrometry studies, indicates that involves DABCO-derived α-substituted ammonium ylides.

Language: Английский

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Metal-Free Catalytic Synthesis of Tetrasubstituted Furans from α-Hydroxy Ketones and Cyano Compounds

Molecules, Journal Year: 2025, Volume and Issue: 30(8), P. 1832 - 1832

Published: April 19, 2025

A novel method for the efficient and straightforward synthesis of tetrasubstituted furans is presented, employing a base-catalyzed reaction α-hydroxy ketones cyano compounds. The proceeds under relatively mild conditions, utilizes readily available starting materials, exhibits good functional group tolerance high yields. Notably, this obviates need expensive metal catalysts introduces crucial groups such as amino moieties. Furthermore, it avoids prerequisite functionalization substrates, thereby enhancing atomic economy.

Language: Английский

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Squaramide Catalyzed Asymmetric Synthesis of Five‐ and Six‐Membered Rings

Asian Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 10(6), P. 1345 - 1376

Published: April 19, 2021

Abstract Chiral analogues of squaramides have been fruitful in organocatalyzed asymmetric reactions over last decade. Alongside other H‐bonding catalysts like ureas, thioureas: proved to be efficient for the formation acyclic and cyclic chiral molecules. A wide range molecules bearing multiple functionalities stereocenters synthesized by using several bifunctional as catalysts. These perform base utilizing basic N atom their extension help stereoinduction forming H‐bonds with suitable H‐bond acceptors. The present review focuses on assembling recent progresses synthesis five six membered rings promoted squaramides. handful articles published research groups documenting construction five‐ six‐membered part interesting complex molecular architectures. Different methodologies conventional formal cycloadditions or cascade engineered through assistance fabricate carbo‐ heterocycles. This also includes dual cooperative catalytic system which squaramide is one

Language: Английский

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Chemodivergent Photocatalytic Synthesis of Dihydrofurans and β,γ‐Unsaturated Ketones

Advanced Synthesis & Catalysis, Journal Year: 2021, Volume and Issue: 363(13), P. 3267 - 3282

Published: April 21, 2021

Abstract A synthetic procedure, catalysed by Ir(ppy) 3 under visible‐light irradiation, for the chemodivergent synthesis of 2,3‐dihydrofurans ( ) or β,γ‐unsaturated ketones 7 starting from α‐halo 1 and alkenes 2 has been developed. The mild reaction conditions redox‐neutral nature process make it particularly sustainable avoiding use both sacrificial reactants stoichiometric strong oxidants. Careful experimental investigations, supported DFT calculations, allowed to disclose in details a possible mechanistic pathway direct chemodivergently either toward , depending not only on substrates, but also choice conditions. magnified image

Language: Английский

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Advances in the Synthesis of Benzo‐Fused Spiro Nitrogen Heterocycles: New Approaches and Modification of Old Strategies

Helvetica Chimica Acta, Journal Year: 2020, Volume and Issue: 103(12)

Published: Nov. 26, 2020

Abstract The review covers the results of studies published in literature on synthesis spiro‐linked heterocycles indole, quinoline, benzoxazine, benzothiazine, indenoquinoxaline, pyridopyrimidine, and acridine series. Possible approaches to spirocycles through a sequence well‐known Knoevenagel , Michael reactions, deamination cyclization 1,2‐dicarbonyl, CH‐acid compounds, direct cycloaddition activated olefins isatins, 3‐alkylideneindoles, 2‐oxindoles, situ generated azomethine ylides, indenoquinoxalines are analyzed. Attention is drawn preparation spiro‐fused compounds using reactions intra‐ intermolecular dearomatization indoles. Recent advances benzo from derivatives 2‐olefin substituted anilines summarized. examples by means metal complexes catalyzed decomposition diazo given. Some syntheses biologically active representatives shown, as well use transformations spiroheterocycles other heterocycles.

Language: Английский

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Organocatalytic Enantioselective Synthesis of Tetrahydro‐Furanyl Spirooxindoles via [3+2] Annulations of 3‐Hydroxyoxindoles and Cyclic Ketolactams

Advanced Synthesis & Catalysis, Journal Year: 2021, Volume and Issue: 363(8), P. 2177 - 2182

Published: Feb. 20, 2021

Abstract Asymmetric construction of pharmacologically interesting tetrahydrofuranyl spirooxindole frameworks has been achieved through organocatalytic [3+2] annulations the readily available 3‐hydroxyoxindoles and pyrrolidone‐derived cyclic ketolactams. A variety chiral spiro products, which contain four contiguous stereocenters including two tetrasubstituted carbon centers, have rapidly synthesized with remarkable results (up to 99% yield, >95:5 dr, 99:1 er). Synthetic derivatization hemiketal moiety enables installation various halogen atoms into structurally complex molecules in a stereospecific manner. Preliminary screening anticancer bioactivity was performed, 4 w showed obvious inhibitory capacity proliferation on panel cancer cell lines. magnified image

Language: Английский

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Coumarin-3-formylpyrazoles as 3-carbon synthons in cyclocondensation for the synthesis of spiro-fused pentacyclic spirooxindoles

Organic & Biomolecular Chemistry, Journal Year: 2019, Volume and Issue: 18(5), P. 845 - 850

Published: Dec. 30, 2019

Coumarin-3-formylpyrazoles have been synthesized and applied as 3-carbon synthons in reaction with 3-hydroxyoxindoles by using DABCO the catalyst. A range of structurally diverse spiro-fused pentacyclic spirooxindoles, bearing a spirooxindole-γ-lactone 3,4-dihydrocoumarin substructure, could be smoothly obtained good to excellent yields (up 99%) diastereoselectivities (all cases >20 : 1 dr). The asymmetric version this tandem was preliminarily investigated chiral organocatalysts.

Language: Английский

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Stereoselective synthesis of hydrazinodihydrofuransviacascade Michael addition–substitution involving the reaction of curcumin and other β-dicarbonyls with α-hydrazinonitroalkenes

Organic & Biomolecular Chemistry, Journal Year: 2019, Volume and Issue: 18(1), P. 140 - 153

Published: Nov. 26, 2019

Reaction of 1,3-dicarbonyls with α-hydrazinonitroalkenes leads to 2-hydrazino-2,3-dihydrofurans high stereoselectivity in the presence atert-leucine derived squaramide and K₂CO₃in aqueous THF.

Language: Английский

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