A simple and sensitive coumarin-based fluorescence probe (ZXD-1) for determination of hydrogen peroxide and its application in bioimaging

Journal of Molecular Structure, Год журнала: 2023, Номер 1299, С. 137124 - 137124

Опубликована: Ноя. 20, 2023

Язык: Английский

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Natural and Synthetic Spirobutenolides and Spirobutyrolactones

Asian Journal of Organic Chemistry, Год журнала: 2020, Номер 9(10), С. 1377 - 1409

Опубликована: Авг. 1, 2020

Abstract Spirobutenolides and spirobutyrolactones structural motifs are widespread in various natural products that exhibit a broad array of biological activities. Additionally, their synthetic analogues also serve as biologically active compounds building blocks complex molecules. Owing to the wide range pharmacological activities diversity spirobutenolides spirobutyrolactones, efficient methodologies have been established construct such interesting scaffolds. In past decades, numerous total syntheses containing reported. Structurally diverse synthesized by using singlet oxygen, Mannich reaction, aldol condensation, rearrangement Reformatsky Michael‐addition cyclization, Diels‐Alder photocyclization pericyclic reactions. Recently, metal‐catalyzed photocatalyzed radical Baylis‐Hillman asymmetric organocatalysis, NHC catalysis, ring contraction reactions, hypervalent iodine catalysis emerged powerful tools architect these nuclei. This review gives an overview advancements chemically relevant origin. It covers newer for construction well along with potential applications.

Язык: Английский

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Organocatalytic Atroposelective Fluorooxindole Addition to Coumarin Michael Acceptors

Chemical Communications, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

Organocatalytic atropisomeric synthesis with fluorinated oxindoles and 4-halo-3-nitrocoumarins gives congested structures displaying a Csp2-Csp3 chirality axis an adjacent tetrasubstituted stereogenic carbon center good yields, up to 97% ee 41 : 1 dr. The scalable dehalogenative C-C bond formation is achieved under mild conditions commercially available urea catalyst.

Язык: Английский

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Enantioselective Synthesis of Bispiro[indanedione-oxindole-cyclopropane]s through Organocatalytic [2+1] Cycloaddition

The Journal of Organic Chemistry, Год журнала: 2022, Номер 88(12), С. 7641 - 7650

Опубликована: Авг. 12, 2022

A series of compounds featuring a novel bispiro[indanedione-oxindole-cyclopropane] moiety have been synthesized through squaramide-catalyzed [2+1] cycloaddition reaction. The tandem Michael-alkylation reaction 2-arylidene-1,3-indanediones with 3-bromooxindoles furnished the cycloadducts in high yields excellent diastereo- and enantioselectivities. ammonium ylide catalytic process, as key intermediate, was revealed by high-resolution mass spectrometry study.

Язык: Английский

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Pyrazoleamides in Catalytic Asymmetric Reactions: Recent Advances

Advanced Synthesis & Catalysis, Год журнала: 2021, Номер 363(14), С. 3380 - 3410

Опубликована: Фев. 23, 2021

Abstract Pyrazoleamides are a class of compounds which have received significant attention in the last years asymmetric catalysis as more reactive and practical surrogates esters or amides. These readily available reagents served variety diastereo‐ enantioselective metal‐ organocatalytic transformations, spanning from simple carbon‐carbon carbon‐heteroatom bond formation to cascade rearrangement reactions, produce valuable classes heterocyclic compounds. More recently, pyrazoleamides proved be pertinent merged with photoredox catalysis, challenging stereoselective bond‐forming occurring directly visible‐light activated substrate/catalyst complex without any charge separation. Both strategies enable new activation concepts useful for production difficult‐to‐access intermediates pharmaceuticals. In this review, an overview progress achieved catalytic reactions 2015 up middle 2020, is illustrated. magnified image

Язык: Английский

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Stereo‐ and Regioselective Construction of Spirooxindoles Having Continuous Spiral Rings via Asymmetric [3+2] Cyclization of 3‐Isothiocyanato Oxindoles with Thioaurone Derivatives

European Journal of Organic Chemistry, Год журнала: 2020, Номер 2020(42), С. 6614 - 6622

Опубликована: Окт. 29, 2020

A highly efficient enantioselective [3+2] cyclization of 3‐isothiocyanato oxindoles with thioaurone derivatives was explored for the synthesis spirooxindoles containing continuous spiral ring structures. Three structures and three consecutive chiral centers (including two spiro quaternary stereocenters) were conveniently constructed at a time. In addition, an uncommon sulfur‐containing spirocyclic same The reaction went smoothly whether alkenyl moiety 2‐position (up to 99 % yield, up ee , > 20:1 dr ) or 3‐position 96 95 12:1 ).

Язык: Английский

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DBU-catalyzed dearomative annulation of 2-pyridylacetates with α,β-unsaturated pyrazolamides for the synthesis of multisubstituted 2,3-dihydro-4H-quinolizin-4-ones

Organic Chemistry Frontiers, Год журнала: 2021, Номер 9(1), С. 88 - 94

Опубликована: Ноя. 9, 2021

DBU-catalyzed dearomative [3 + 3] annulation of 2-pyridylacetates and α,β-unsaturated pyrazolamides for the synthesis multisubstituted 2,3-dihydro-4 H -quinolizin-4-ones was developed.

Язык: Английский

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Asymmetric Formal (3 + 2) Cyclocondensation of Coumarin-3-Formylpyrazoles as 3-Carbon Partners with 3-Hydroxyoxindoles via Esterification/Michael Addition Sequence

The Journal of Organic Chemistry, Год журнала: 2022, Номер 87(22), С. 15210 - 15223

Опубликована: Окт. 28, 2022

The first enantioselective formal (3 + 2) cyclocondensation involving α,β-unsaturated pyrazoleamides as 3-carbon partners was accomplished in a stepwise fashion. esterification/Michael addition sequence is promoted by Zn(OTf)2 and quinine-squaramide derivative, respectively. protocol enables access to spiro-fused pentacyclic spirooxindoles from coumarin-3-formylpyrazoles 3-hydroxyoxindoles good satisfactory overall yields (up 91%) with excellent dr (all cases >20:1 dr) high ee values 99%). Mechanistic investigations contributed shedding light on the event of process.

Язык: Английский

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A water-promoted catalytic hydrodecarboxylation of conjugated carboxylic acids under open air conditions at room temperature

Green Chemistry, Год журнала: 2023, Номер 25(8), С. 3040 - 3045

Опубликована: Янв. 1, 2023

The first example of organocatalyzed ionic hydrodecarboxylation conjugated carboxylic acids has been developed under open air conditions at room temperature.

Язык: Английский

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A facile synthesis of novel oxindole-dihydrocoumarins via tandem Michael addition-decarboxylation

Tetrahedron, Год журнала: 2024, Номер 166, С. 134229 - 134229

Опубликована: Авг. 27, 2024

Язык: Английский

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