Asymmetric Synthesis of Hydroxylated Pyrrolidines, Piperidines and Related Bioactive Compounds: From N-Acyliminium Chemistry to N-α-Carbanion Chemistry

Oxazolidinones are an important class of heterocyclic compounds that are used as chiral auxiliaries in asymmetric synthesis and as biologically active pharmaceutical agents. Moreover, carbohydrates are ideal scaffolds to generate libraries of bioactive compounds due the presence of defined configuration. We report here asymmetric alkylation studies on N-derivatized glucose-and allose-based spirooxazolidinones which do act as chiral auxiliaries.

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Asymmetric Synthesis of Isoxazol-5-ones and Isoxazolidin-5-ones

Synthesis ◽

10.1055/s-0040-1706483 ◽

2020 ◽

Vol 53 (01) ◽

pp. 107-122

Author(s):

Jean-François Brière ◽

Mario Waser ◽

Antonio Massa ◽

Antonio Macchia ◽

Andreas Eitzinger

Keyword(s):

Asymmetric Synthesis ◽

Bioactive Compounds ◽

Related Compound ◽

Building Blocks ◽

Metal Catalysts ◽

Enantioselective Synthesis

AbstractIsoxazol-5-ones and isoxazolidin-5-ones represent two important classes of heterocycles, with several applications as bioactive compounds and as versatile building blocks for further transformations. Unlike the parent aromatic isoxazoles, the presence of one or two stereocenters in the ring renders their asymmetric construction particularly important. In this review, starting from the description of general features and differences between these two related compound families, we present an overview on the most important enantioselective synthesis strategies to access these heterocycles. Both chiral metal catalysts and organocatalysts have recently been successfully employed for this task and some of the most promising approaches will be discussed.1 Introduction2 Isoxazol-5-ones as Nucleophiles2.1 Isoxazol-5-ones as C-Nucleophiles2.2 Isoxazol-5-ones as N-Nucleophiles2.3 Isoxazol-5-ones as C-Nucleophiles in Cyclization Processes3 Asymmetric Construction of Isoxazolidin-5-ones3.1 Enantioselective α-Functionalizations of Isoxazolidin-5-ones4 Arylideneisoxazol-5-ones in Conjugated Addition5 Conclusions

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Asymmetric Organocatalytic Syntheses of Bioactive Compounds

Current Organic Synthesis ◽

10.2174/1570179418666210728145206 ◽

2021 ◽

Vol 18 ◽

Author(s):

Estibaliz Sansinenea ◽

Aurelio Ortiz

Keyword(s):

Natural Products ◽

Asymmetric Synthesis ◽

Bioactive Compounds ◽

Cascade Reactions ◽

Biologically Active ◽

Active Compounds ◽

Total Syntheses ◽

Main Structure ◽

New Methodologies ◽

High Stereoselectivity

Background: The total syntheses of complex natural products have evolved to include new methodologies to save time, simplifying the form to achieve these natural compounds. Objective: In this review, we have described the asymmetric synthesis of different natural products and biologically active compounds of the last ten years until the current day. Results: An asymmetric organocatalytic reaction is the key to generate stereoselectively the main structure with the required stereochemistry. Conclusion: Even more remarkable, the organocatalytic cascade reactions, which are carried out with high stereoselectivity, as well as a possible approximation of the organocatalysts activation with substrates are also described.

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Step economy in the Stereoselective Synthesis of Functionalized Oxindoles via Organocatalytic Domino/One-pot Reactions

Current Organic Chemistry ◽

10.2174/1385272825666210518124845 ◽

2021 ◽

Vol 25 ◽

Author(s):

Martina Bortolami ◽

Francesca Leonelli ◽

Marta Feroci ◽

Fabrizio Vetica

Keyword(s):

Natural Products ◽

Asymmetric Synthesis ◽

Bioactive Compounds ◽

Stereoselective Synthesis ◽

Environmentally Friendly ◽

Important Class ◽

One Pot ◽

Asymmetric Organocatalysis ◽

Toxic Approach

: Oxindoles are an important class of heterocyclic scaffolds widely present in natural products and bioactive compounds. For this reason, a plethora of methodologies for the stereoselective synthesis of enantioenriched oxindoles has been studied over the years. Among all the reported synthetic strategies, organocatalysis has proven to be a powerful tool for the asymmetric synthesis of this class of compounds being a step- and atom-economical, environmentally friendly, and non-toxic approach. This review will outline the application of asymmetric organocatalysis in the synthesis of chiral oxindole-based structures, relying on domino/one-pot reaction sequences in a step-economical fashion.

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Enantioselective Vinylogous Reactions of 3-Alkylidene Oxindoles

Synthesis ◽

10.1055/s-0037-1609731 ◽

2018 ◽

Vol 50 (13) ◽

pp. 2463-2472 ◽

Cited By ~ 3

Author(s):

Renato Dalpozzo ◽

Raffaella Mancuso

Keyword(s):

Natural Products ◽

Asymmetric Synthesis ◽

Bioactive Compounds ◽

Carbonyl Compounds ◽

Important Class ◽

Chiral Molecules ◽

Research Groups ◽

Mannich Reactions ◽

The Creation ◽

Synthetic Derivatives

Oxindoles represent an important class of bioactive compounds and synthetic derivatives found in many natural products. Most of these compounds are chiral molecules and the challenge of their asymmetric synthesis has fascinated many research groups. In particular, the creation of chiral centers out of the oxindole ring by vinylogous addition to 3-alkylidene-substituted oxindoles (3-alkylidene-1,3-dihydro-2H-indol-2-ones) has emerged in recent years. This review aims to give an overview of this topic.1 Introduction2 Aldol and Mannich Reactions3 Addition to Unsaturated Carbonyl Compounds4 Addition to Nitroalkenes5 Miscellaneous6 Conclusion

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