Asymmetric Tandem Michael Addition/Interrupted Nef Reactions of Nitromethane with Oxindole-Derived Alkenes: Enantioselective Synthesis of Spiro-polycyclic Oxindoles

Organic Letters, Journal Year: 2024, Volume and Issue: 26(15), P. 3279 - 3283

Published: April 5, 2024

Chiral spiro-polycyclic oxindoles are valuable heterocyclic ring systems that widely distributed in natural alkaloids and biologically active compounds. Herein, we reported an asymmetric tandem Michael addition/interrupted Nef reaction of nitromethane with oxindole-derived alkenes catalyzed by a chiral 2-aminobenzimidazole bifunctional organocatalyst. A series novel enantiomerically enriched oxindole derivatives bearing oxime group were synthesized moderate to excellent isolated yields (up 99%) level enantioselectivities 99% ee). Furthermore, the antiproliferation activity resulting evaluated, compound 2d demonstrated promising anticancer properties against HCT116 (IC50 = 14.08 μM) HT29 15.46 cell lines.

Language: Английский

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Pd-Catalyzed Cross-Coupling of Cyclopropanols with 2-Br-p-Quinone Methides/2-Br-Cinnamate Esters Followed by a 1,6- and 1,4-Conjugate Addition Reaction

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

Published: March 10, 2025

A novel cascade Pd-catalyzed cross-coupling reaction of cyclopropyl alcohol-derived ketone homoenolate with 2-Br-p-quinone methides and 2-Br-cinnamate esters followed by a 1,6- 1,4-conjugate addition is disclosed. This protocol converts various alcohols into homoenolate, which undergoes C-C bond formation 2-Br p-quinone esters. The salient features this methodology include its operational simplicity, mild conditions, an environmentally benign protocol, high efficiency, good to excellent yields, wide substrate scope.

Language: Английский

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Metal-Free Regioselective Oxa-Michael Approach to Access Spirooxindole-Fused Tetrahydrofuran/Tetrahydropyran through [3 + 2]/ [4 + 2] Spirocyclization of Methyleneindolinones with Haloalcohols

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(13), P. 9389 - 9404

Published: June 24, 2024

An efficient one-pot metal-free, base-catalyzed method has been developed for the regioselective [3 + 2]/[4 2] annulation reactions of electrophilic methyleneindolinones with haloalcohols to furnish spirooxindole derivatives under mild reaction conditions. This afforded corresponding products two contiguous stereocenters including a quaternary center in good excellent yield (up 95%) moderate diastereoselectivities 12.5:1 dr) complete regioselectivity.

Language: Английский

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A one-pot Synthesis of 2,3-Dihydrobenzofurans, Benzofuran-2(3H)-ones, and Indoles via [4 + 1] Annulation Reaction of ortho-substituted para-Quinone Methides and Bromonitromethane

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

A facile one-pot synthesis of oxygen- and nitrogen-containing benzoheterocycles has been achieved through [4 + 1] annulation para -quinone methides, followed by an oxidation/elimination sequence.

Language: Английский

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Comprehensive In Silico Analysis of Uncaria Tomentosa Extract: Chemical Profiling, Antioxidant Assessment, and CLASP Protein Interaction for Drug Design in Neurodegenerative Diseases

Current Computer - Aided Drug Design, Journal Year: 2024, Volume and Issue: 21(1), P. 94 - 109

Published: Feb. 4, 2024

Background: Uncaria tomentosa is a traditional medicinal herb renowned for its anti-inflammatory, antioxidant, and immune-enhancing properties. In the realm of neurodegenerative diseases (NDDS), CLASP proteins, responsible regulating microtubule dynamics in neurons, have emerged as critical players. Dysregulation proteins associated with NDDS, such Alzheimer's, Parkinson's, Huntington's diseases. Consequently, comprehending role NDDS holds promise development innovative therapeutic interventions. Objectives: The objectives research were to identify phytoconstituents hydroalcoholic extract (HEUT), evaluate antioxidant potential through vitro free radical scavenging assays explore interaction using silico molecular docking studies. Methods: HPLC LC-MS techniques used quantify phytochemicals HEUT. was assessed DPPH, ferric reducing power (FRAP), nitric oxide (NO) superoxide (SO) methods. Interactions between conventional quinovic acid, chlorogenic epicatechin, corynoxeine, rhynchophylline syringic acid studied Auto Dock 4.2. Results: HEUT demonstrated highest concentration derivatives. exhibited strong radical-scavenging activity IC50 values 0.113 μg/ml (DPPH) 9.51 μM (FRAP). It also suppressed NO production by 47.1 ± 0.37% at 40 inhibited 77.3 0.69% SO generation. Additionally, revealed NDDS. Conclusion: protein suggest promising treating linked dysregulation.

Language: Английский

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Synthesis of Aza‐Bicyclic Maleimide Skeleton by Addition‐Ring Opening Cascade Reaction of Vinylogous Oxindole

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 27(20)

Published: April 1, 2024

Abstract An efficient method has been developed to facilitate the addition‐ring opening cascade reaction of vinylogous oxindole, resulting in synthesis a variety aza‐bicyclic maleimide derivatives with high yields and exceptional diastereoselectivities. Furthermore, product could be effectively easily transformed into difluoromethylenecyclohexane skeleton through dehydrofluorination process. This methodology demonstrates significant potential for skeleton, which possesses biological or pharmaceutical activity.

Language: Английский

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Five-membered ring systems: Pyrroles and benzo analogs

Progress in heterocyclic chemistry, Journal Year: 2024, Volume and Issue: unknown, P. 123 - 173

Published: Jan. 1, 2024

Language: Английский

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