Asymmetric Synthesis Of Natural Products Research Articles

Recent asymmetric synthesis of natural products bearing an α-tertiary amine moiety via temporary chirality induction strategies.

Covering: 2013 to 2023The α-tertiary amine moiety is a common structural motif in natural alkaloids and is frequently associated with intriguing biological activities and inherent synthetic challenges. A major hurdle in the total synthesis of these alkaloids is the asymmetric construction of the α-tertiary amine moiety. Temporary chirality inductions have been effective strategies employed to address this issue, particularly in natural product synthesis. The temporary chirality induction strategies in α-tertiary amine synthesis can be broadly classified into three categories based on the types of temporary chirality involved: Seebach's self-regeneration of stereocenters (SRS), C-to-N-to-C chirality transfer, and memory of chirality (MOC). This review highlights the recent advancements in temporary chirality induction strategies for the total synthesis of α-tertiary amine-containing natural products between 2013 and 2023.

Chiral Hydroxamic Acid Ligands in the Asymmetric Synthesis of Natural Products

Chiral hydroxamic acid (HA) and bis-hydroxamic acid (BHA) ligands have made significant contributions to the field of asymmetric synthesis, particularly in the synthesis of natural products. These ligands possess unique molecular structures that allow for exceptional stereochemical control, leading to their widespread use in catalytic systems. This review highlights the advancements made in asymmetric synthesis using chiral hydroxamic acid and bis-hydroxamic acid ligands and their impact on the synthesis of complex natural products. This discussion encompasses their role in enantioselective C–C bond formation, the functionalization of C–H bonds, the asymmetric transformations involving heteroatoms, and their application in the total synthesis of natural products. The versatility and efficiency of chiral hydroxamic acid ligands and bis-hydroxamic acid ligands make them invaluable tools for synthetic chemists working towards the efficient and selective synthesis of natural products. This review provides a comprehensive overview of their contributions, showcasing their potential to expand the boundaries of chemical synthesis and access the diverse array of natural product scaffolds.

Recent Applications of Asymmetric Organocatalytic Methods in Total Synthesis

AbstractNatural products are the great sources of drugs and leading compounds in drug discovery, as it has been estimated that most of the current medicines are derived from natural products. Total synthesis of natural products, especially those of biological activities, has been an important part of organic chemistry, which, besides its potential practical utilities, also provides new inspirations and novel synthetic methodologies. Over the past two decades, organocatalysis has been shown to be very effective in controlling the stereochemistry of the reaction products and has found many applications in the asymmetric synthesis of natural products and related compounds. In this review we will attempt to summarize some applications of asymmetric organocatalysis in the total synthesis of natural products and related compounds in the past seven years.

Catalytic Synthesis of Optically Active Polycyclic Heterocyclic Compounds

In basic pharmaceutical sciences to achieve drug development, research on the efficient chemical synthesis of small molecules having cyclic skeletons is important. We have been engaged in the development of artificial catalysts for asymmetric ring formation reactions that exclusively synthesize right-handed or left-handed cyclic compounds and have achieved the construction of optically active cyclic skeletons using our original catalysts. The synthesis of biologically active compounds was facilitated through six-membered ring construction by Diels-Alder reaction of Danishefsky diene; however, no asymmetric variant of the reaction has been achieved. We approached this unresolved issue using multi-coordinated lanthanide metals. A new chiral lanthanide catalyst was developed, and the catalytic asymmetric Diels-Alder reaction of Danishefsky diene was realized for the first time. By modifying the chemical structure of Danishefsky diene, we applied the lanthanide catalyst to the syntheses of polycyclic compounds and biologically active compounds. We achieved the asymmetric synthesis of natural products, antibacterial and antimalarial compounds, and an anti-obesity drug lead compound. Moreover, the novel catalyst exhibited higher performance than the previously reported ones. The latest generation of the catalyst can be handled stably in air at room temperature. Furthermore, we succeeded in the development of new catalysts by focusing on the properties of its metal precursors, such as nickel and indium, and achieved the construction of polycyclic skeletons by using these catalysts.

Pyroglutamic Acid and its Derivatives: The Privileged Precursors for the Asymmetric Synthesis of Bioactive Natural Products

Pyroglutamic acid is one of the privileged asymmetric precursors for the synthesis of a variety of molecules such as Angiotensin-Converting Enzyme (ACE) inhibitors, angiotensin II receptor subtypes (AT-1 receptor antagonists), as well as bioactive natural products. Starting with primary reports in 1980’s, last almost four decades has witnessed a rapid overgrowth of publications using pyroglutamic acid as a preferred asymmetric precursor and these have been well documented. Pyroglutamic acid has two differential carbonyl groups a lactam carbonyl and a carboxylic functionality along with an NH group, and all of these functionalities can be further derivatized/ transformed and in turn opened avenues for the synthesis of variety of molecules. Derived easily from glutamic acid by internal cyclization, pyroglutamic acid offers a cheap and very good source of chirality and has provided an important tool for the synthesis of natural products/intermediates to natural products. Herein, we wish to describe the exploitation of the chemistry of pyroglutamic acid and its derivatives in the asymmetric synthesis of natural products establishing its versatility as a privileged asymmetric precursor.

Internal Chelation within Functionalized Organoindium Reagents: Prospects for Regio- and Stereocontrol in the Allylation, Propargylation and Allenylation of Carbonyl Compounds

The low basicity, selective nucleophilicity, and mildness of organoindium compounds allow for the incorporation of many important yet sensitive functional groups into their structure, including examples capable of intramolecularly chelating the indium center within these reagents. The specific nature of such chelated organoindiums causes the reactions involving them to proceed in a unique manner, often with regio- and stereoselectivity inaccessible with simple organometallic reagents. This review covers the rare examples of regio- and stereoselective allylation, propargylation, and allenylation of carbonyl compounds with chelated organoindiums, including brief descriptions of the applications of the resulting adducts in the asymmetric synthesis of natural products and synthetic targets of biological and medicinal interest.1 Introduction2 Internal Chelation Control in the Allylation Processes2.1 Allylindiums with a Chelating Center at the γ-Position2.2 Allylindiums with a chelating Center at the δ-Position2.3 Allylindiums with a Chelating Center at ε- and ζ-Positions2.4 Allylindiums with a Chelating Center at γ′- and δ′-Positions3 Internal Chelation Control in Propargylation and Allenylation Processes­3.1 Additions of Chelated Allenylindiums3.2 Additions of Chelated Propargylindiums4 Conclusion

Recent Applications in the Use of Sulfoxides as Chiral Auxiliaries for the Asymmetric Synthesis of Natural and Biologically Active Products

The contribution of chiral sulfoxides as versatile auxiliaries in the field of organic chemistry has shown a prevalent interest in the asymmetric synthesis of natural products during the last 45 years. In this short review, we report the recent applications of these chiral auxiliaries to the synthesis of natural and biological active products highlighted from 2010 to 2019. We hope to allow the reader to have an overview of the potential of sulfoxide chemistry in the field of enantio­selective synthesis.1 Introduction2 Diastereoselective Additions to Ketones2.1 Reduction of β-Keto Sulfoxides2.2 Reduction of β-Keto Sulfoxides Followed by Bromohydrin Forma tion3 Synthesis of an α-Amino α′-Sulfinyl Ketone Followed by Diastere oselective Reduction of the β-Keto Sulfoxide4 Diastereoselective Addition of Carbanionic Chiral Sulfoxides4.1 Addition to an Aldehyde4.1.1 Aldol Reactions4.1.2 Reformatsky-Type Reactions4.2 Additions to Chiral Sulfinimines5 Diastereoselective Cyclization Reactions Directed by a Chiral Sulf oxide5.1 1,4-Radical Additions5.2 Intramolecular Conjugate Additions5.3 Nazarov Cyclizations5.4 Diels–Alder Reactions6 Atropodiastereoselective Synthesis7 Conclusion

Recent Advances in Natural Products Synthesis Using Bifunctional Organocatalysts Bearing a Hydrogen‐Bonding Donor Moiety

AbstractOrganocatalysis is widely used for the asymmetric synthesis of natural products and pharmaceuticals, and bifunctional organocatalysts are particularly effective for controlling stereochemistry. Here, we present an overview of natural products syntheses involving bifunctional catalysts bearing a hydrogen‐bonding donor moiety reported during the last five years.

Efficient Enantioselective Syntheses of Chiral Natural Products Facilitated by Ligand Design.

The employment of enantioselective transition-metal-catalyzed transformations as key steps in asymmetric natural product syntheses have attracted considerable attention in recent years owing to their versatile synthetic utilities, mild conditions and high efficiency in chirality generation. The chiral catalysts or supporting ligands are believed to be crucial for the requisite reactivity and enantioselectivity. Therefore, the rational design of chiral ligands is at the heart of developing new asymmetric transition-metal catalyzed reactions and provides an avenue to the asymmetric synthesis of natural products. Our group has been engaged in the development of transition-metal-catalyzed enantioselective cross-coupling, cyclization and other related reactions and the application of these methodologies to natural product syntheses. In this account, we summarized our recent synthetic efforts towards the efficient total syntheses of several different types of natural products including terpenes, alkaloids and polyketides facilitated by the design of a series of versatile P-chiral phosphorous ligands.

Asymmetric Vinylogous Aldol-type Reactions of Aldehydes with Allyl Phosphonate and Sulfone

SummaryTwo catalytic asymmetric vinylogous aldol-type reactions of aldehydes with allyl phosphonate and allyl sulfone have been uncovered in good to high yields for the first time. The bulky ligand—(R)-DTBM-SEGPHOS—was found to be the key to perfectly control both regio- and enantioselectivities. Transformations of the vinylogous products (including Horner-Wadsworth-Emmons and Julia olefinations) were successfully realized by virtue of the phosphonate and sulfone moieties. Moreover, the present methodology was successfully applied in the asymmetric synthesis of natural products.

Catalytic Asymmetric Vinylogous Aldol-Type Reactions of Aldehydes with Allyl Phosphonate and Allyl Sulfone

Two catalytic asymmetric vinylogous aldol-type reactions of aldehydes with allyl phosphonate and allyl sulfone have been uncovered in good to high yields for the first time. The bulky ligand — (R)-DTBM-SEGPHOS was found to be the key to perfectly control both regio- and enantioselectivities. Transformations of the vinylogous products (including Horner-Wadsworth-Emmons olefination and Julia olefination) were successfully realized by virtue of the phosphonate and the sulfone moieties. Moreover, the present methodology was successful applied in the asymmetric synthesis of natural products.

抗結核薬および抗がん剤のリード創製を志向した天然物の触媒的不斉全合成

抗結核薬および抗がん剤のリード創製を志向した天然物の触媒的不斉全合成

Stereospecific and stereoconvergent cross-couplings between alkyl electrophiles

The development of metal-catalysed cross-coupling reactions between one electrophilic and one organometallic nucleophilic partner has revolutionized the practice of chemical synthesis, with coupling reactions between sp2 centres now commonplace in both academic and industrial research. Methods to allow coupling of sp3 centres are rapidly being developed, with many recent advances even enabling control of the absolute configuration of newly formed stereogenic centres. The related cross-electrophile couplings have not been developed as thoroughly owing to the challenge of obtaining cross-selectivity between two substrates with similar reactivity. However, the discovery of improved methods to address this challenge has led to significant recent progress. The development of enantioselective cross-electrophile coupling reactions is an emerging area of research. Both stereoconvergent and stereospecific variants have been reported for the synthesis of a range of products containing tertiary stereogenic centres. Many of these transformations build on lessons learnt from traditional (electrophile–nucleophile) cross-couplings of alkyl electrophiles. For example, all enantioselective transformations described to date use a nickel catalyst. Continued progression is likely to provide strategic disconnections for asymmetric synthesis of natural products and medicinal agents. The cross-electrophile coupling approach to stereocontrolled C–C bond formation provides a complementary alternative to traditional cross-coupling methods. This Perspective provides an overview of the recent development of nickel-catalysed asymmetric cross-electrophile coupling reactions. Both stereoconvergent and stereospecific examples are considered and mechanistic details are highlighted.

ChemInform Abstract: Asymmetric Reactions Employing 1,3‐Dipoles

AbstractReview: 54 refs + subrefs.

Asymmetric reactions employing 1,3-dipoles

The preparation of heterocyclic compounds using 1,3-dipolar cycloaddition chemistry is now well recognized in the fields of organic synthesis, drug discovery efforts, polymer chemistry, and materials science. As highlighted in this review, a growing area of interest in organic synthesis involves the enantioselectivity aspects of dipolar cycloaddition chemistry for the preparation of many different classes of natural products. Asymmetric synthesis of natural products using chiral substrates has been elegantly accomplished over the past decade using an assortment of dipole intermediates and represents the focus of this review article.

ChemInform Abstract: Asymmetric Synthesis of Natural Products and Medicinal Drugs Through One‐Pot‐Reaction Strategies

AbstractReview: [78 refs.

Asymmetric Synthesis of Natural Products and Medicinal Drugs through One-Pot-Reaction Strategies

One-pot synthesis has become an important subject of modern synthetic chemistry owing to its efficiency, versatility and expediency in constructing complicated polycyclic ring systems, especially with a sustainable and catalytic aspect. This review aims to highlight the recent advances in this area with specific emphasis on the asymmetric synthesis of natural products and related core structures as well as medicinal drugs via one-pot operation. 1 Introduction 2 Double Reactions 3 Triple Reactions 4 Quadruple Reactions 5 Pot-Economy Reactions 6 Conclusions

Asymmetric total synthesis of Apocynaceae hydrocarbazole alkaloids (+)-deethylibophyllidine and (+)-limaspermidine.

An unprecedented asymmetric catalytic tandem aminolysis/aza-Michael addition reaction of spirocyclic para-dienoneimides has been designed and developed through organocatalytic enantioselective desymmetrization. A unified strategy based on this key tandem methodology has been divergently explored for the asymmetric total synthesis of two natural Apocynaceae alkaloids, (+)-deethylibophyllidine and (+)-limaspermidine. The present studies not only enrich the tandem reaction design concerning the asymmetric catalytic assembly of a chiral all-carbon quaternary stereocenter contained in the densely functionalized hydrocarbazole synthons but also manifest the potential for the application of the asymmetric catalysis based on the para-dienone chemistry in asymmetric synthesis of natural products.

Synthetic studies of alkaloids containing pyrrolidine and piperidine structural motifs.

Awarding Institute: Goa University (India) Date awarded: December, 2013 Supervisor: Prof. Santosh G. Tilve, HOD Chemistry, Goa University, Goa (India)

비고리 알릴아민 화합물의 입체선택적 이중알코올화 반응

비고리 알릴아민 화합물의 이중알코올화 반응은 아미노 다이올 구조를 도입할 수 있는 효율적인 합성법으로 아미노 다이올 구조를 포함하는 다양한 생리활성 천연물의 효율적인 합성에 적용될 수 있다. 본 리뷰에서는 기질 그 자체, 혹은 카이랄 리간드를 이용한 다양한 입체선택적 이중알코올화 반응들을 소개하고 이를 실제 천연물의 합성에 적용한 최근의 반응 결과들을 살펴보고자 한다. The dihydroxylation reaction of allylic amines is a facile and useful synthetic method to obtain amino diol structures that are widely found in lots of biologically important natural products. This review will focus on the recent methods of both substrate-controlled and ligand-controlled dihydroxylation reactions of acyclic allylic amines. In addition, several applications of the diastereoselective dihydroxylation methods to asymmetric syntheses of natural products are presented.