Asymmetric Organocatalytic [3 + 2]-Cycloaddition of N-Alkoxy-4-oxo-acrylamides with Isatin-Derived Ketimines: Access to Enantioselective Synthesis of Spirooxindole-imidazolidinones

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: April 27, 2025

The spirooxindole framework is a privileged motif in numerous biologically significant natural products and has been demonstrated as crucial core scaffold variety of medicinally compounds. Herein, we achieved highly efficient enantioselective [3 + 2]-cycloaddition reaction N-alkoxy-4-oxo-acrylamides with isatin-derived ketimines. This method enabled the precise synthesis chiral spirooxindole-imidazolidinone derivatives, which are notable for their intricate structures presence quaternary centers. Our approach utilized an organocatalytic strategy hydrogen-bonding bifunctional squaramide-based catalyst. impressive results, achieving high yields exceptional enantioselectivities >99% ee majority substrates, even when employing only 2 mol %

Language: Английский

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Base-promoted [3+2]-cycloaddition of N-alkoxy-4-oxo-acrylamides with isatins for stereoselective synthesis of spirooxindole-2-oxazolidinones

Tetrahedron Letters, Journal Year: 2025, Volume and Issue: unknown, P. 155624 - 155624

Published: May 1, 2025

Language: Английский

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Substrate‐Controlled Regioselectivity Switch in a Three‐Component 1,3‐Dipolar Cycloaddition Reaction to Access 3,3′‐Pyrrolidinyl‐Spirooxindoles Derivatives

Advanced Synthesis & Catalysis, Journal Year: 2022, Volume and Issue: 364(12), P. 2047 - 2052

Published: May 12, 2022

Abstract The additive‐free 1,3‐dipolar cycloaddition reaction of isatin‐derived azomethine ylides with α‐cyano‐α,β‐unsaturated compounds was developed, which enabled diversity‐oriented synthesis a series novel and structurally complex 3,3′‐pyrrolidinyl‐spirooxindoles derivatives containing four contiguous two quaternary stereogenic centers in high yields (up to 92%) excellent diastereoselectivities >25:1 dr). displays switchable regioselectivity depending on the steric effect substrates. magnified image

Language: Английский

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Synthesis of tryptanthrin appended dispiropyrrolidine oxindoles and their antibacterial evaluation

RSC Medicinal Chemistry, Journal Year: 2023, Volume and Issue: 14(6), P. 1165 - 1171

Published: Jan. 1, 2023

The synthesis of sixteen tryptanthrin appended dispiropyrrolidine oxindoles, employing [3 + 2] cycloaddition tryptanthrin-derived azomethine ylides with isatilidenes, and their detailed antibacterial evaluation is described.

Language: Английский

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Asymmetric α-Regioselective [3 + 2] Annulation of Morita–Baylis–Hillman Carbonates: Construction of Three Contiguous Stereocenters with Vicinal Quaternary Carbon Centers

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(15), P. 9593 - 9606

Published: July 14, 2022

Asymmetric α-regioselective annulation of MBH carbonates with 4-arylmethylisoxazol-5-ones has been developed to afford spirocyclic oxindole derivatives containing three contiguous stereogenic centers and vicinal all-carbon quaternary chiral centers. This reaction exhibits a broad substrate scope excellent functional group tolerance. Excellent yields high diastereo- enantioselectivities were obtained in this efficient organocatalytic reaction.

Language: Английский

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Asymmetric Friedel–Crafts Alkylation of Indoles Catalyzed by Chiral Aziridine-Phosphines

Catalysts, Journal Year: 2020, Volume and Issue: 10(9), P. 971 - 971

Published: Aug. 26, 2020

Over the course of present studies, a series optically pure phosphines functionalized by chiral aziridines was synthesized in reasonable/good chemical yields. Their catalytic activity checked enantioselective Friedel–Crafts alkylation indoles β-nitrostyrene presence copper(I) trifluoromethanesulfonate benzene complex. The corresponding products were achieved efficiently terms yield and enantioselectivity (up to 85% some cases).

Language: Английский

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Trienamine catalysed unprecedented remote olefin E/Z isomerisation/[4 + 2]-cycloaddition reaction to access spirooxindole hexahydroindoles

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(5), P. 945 - 949

Published: Jan. 1, 2023

Herein, for the first time, we report asymmetric synthesis of an unexpected stereoisomer spirohexahydroindole via a trienamine-catalysed remote olefin E/Z isomerisation/[4 + 2]-cycloaddition reaction. The reaction afforded vast library aesthetically pleasing spirooxindole hexahydroindole scaffolds with exceptional enantio- and diastereo-selectivities (up to 95% yield, 99% ee >99 : 1 dr). In addition, demonstrated synthetic transformation enantiomerically pure hexahydroindoles synthesize alkyl homologated fluoro-pyranooctahydroindole moieties four seven contiguous stereocenters, respectively, in excellent yield selectivities. We have also evidence proposed pathway through NMR investigations.

Language: Английский

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Access to Spirooxindole-Fused Cyclopentanes via a Stereoselective Organocascade Reaction Using Bifunctional Catalysis

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(12), P. 7724 - 7735

Published: Jan. 27, 2023

The present study reports an asymmetric organocascade reaction of oxindole-derived alkenes with 3-bromo-1-nitropropane efficiently catalyzed by the bifunctional catalyst. Spirooxindole-fused cyclopentanes were produced in moderate-to-good isolated yields (15-69%) excellent stereochemical outcomes. synthetic utility protocol was exemplified on a set additional transformations corresponding spirooxindole compounds.

Language: Английский

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Construction of C2‐Spirocyclopropyl‐Indolin‐3‐Ones through Base‐Promoted [2+1] Annulation Reaction of Indolin‐3‐ones with Bromosulfonium Salts

European Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 26(15)

Published: March 15, 2023

Abstract A simple base‐promoted [2+1] annulation of indolin‐3‐ones and bromosulfonium salts has been developed in this article. This strategy uses easily prepared 1 as C1 synthons 2 C2 under mild reaction conditions, 33 examples C2‐spirocyclopropyl‐indolin‐3‐ones were obtained with up to 99 % yield >20 : dr.

Language: Английский

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Evaluation of antibiofilm properties of dehydroacetic acid (DHA) grafted spiro-oxindolopyrrolidines synthesized via multicomponent 1,3-dipolar cycloaddition reaction

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: Sept. 15, 2023

Abstract The current work involves the use of dehydroacetic acid based chalcone derivatives for synthesis spirooxindole grafted pyrrolidine moieties. All synthesized compounds have been characterized using spectroscopic techniques such as NMR ( 1 H-NMR and 13 C-NMR), IR, mass elemental analysis. Molecular mechanics studies were performed to comprehend regioselectivity in product formation. docking was with few bacterial proteins Bacillus subtilis Pseudomonas aeruginosa responsible biofilm formation followed by molecular dynamics simulations potential lead compound. Further, corroborate results obtained via silico study, anti-biofilm activity etc. 4a – e ) checked effectiveness against Taken together, this study opens up explore these compounds’ multiple roles diverse fields arena medical sciences.

Language: Английский

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