Versatility of glycals in synthetic organic chemistry: coupling reactions, diversity oriented synthesis and natural product synthesis

2019 ◽  
Vol 17 (17) ◽  
pp. 4153-4182 ◽  
Author(s):  
Henok H. Kinfe
Keyword(s):  
Organic Chemistry ◽  
Natural Products ◽  
Natural Product ◽  
Stereoselective Synthesis ◽  
Natural Product Synthesis ◽  
Coupling Reactions ◽  
Diversity Oriented Synthesis ◽  
Synthetic Organic Chemistry

Versatility of glycals in the stereoselective synthesis of natural products.

scholarly journals Synthesis of spirocyclic scaffolds using hypervalent iodine reagents

2018 ◽  
Vol 14 ◽  
pp. 1778-1805 ◽  
Author(s):  
Fateh V Singh ◽  
Priyanka B Kole ◽  
Saeesh R Mangaonkar ◽  
Samata E Shetgaonkar
Keyword(s):  
Organic Chemistry ◽  
Heavy Metals ◽  
Natural Product ◽  
Organic Synthesis ◽  
Stereoselective Synthesis ◽  
Natural Product Synthesis ◽  
Hypervalent Iodine ◽  
Toxic Heavy Metals ◽  
Synthetic Organic Chemistry ◽  
The Past

Hypervalent iodine reagents have been developed as highly valuable reagents in synthetic organic chemistry during the past few decades. These reagents have been identified as key replacements of various toxic heavy metals in organic synthesis. Various synthetically and biologically important scaffolds have been developed using hypervalent iodine reagents either in stoichiometric or catalytic amounts. In addition, hypervalent iodine reagents have been employed for the synthesis of spirocyclic scaffolds via dearomatization processes. In this review, various approaches for the synthesis of spirocyclic scaffolds using hypervalent iodine reagents are covered including their stereoselective synthesis. Additionally, the applications of these reagents in natural product synthesis are also covered.

scholarly journals Synthetic organic chemistry in China: building on an ancient tradition—an interview with Qi-Lin Zhou and Xiaoming Feng

2017 ◽  
Vol 4 (3) ◽  
pp. 437-440
Author(s):  
Philip Ball
Keyword(s):  
Organic Chemistry ◽  
Natural Products ◽  
Natural Product ◽  
Organic Synthesis ◽  
Anticancer Agents ◽  
Natural Product Synthesis ◽  
Chiral Molecules ◽  
Alternative Source ◽  
Natural Product Chemistry ◽  
Product Chemistry

Abstract If the core of chemistry is making molecules, then the construction of those found in nature—natural products—has long been regarded as one of the highest forms of the art in synthesis. These molecules, produced by living organisms for a variety of purposes, are a key source of pharmaceuticals such as antibiotics and anticancer agents. The medicinal value of natural products has been known for centuries via herbal treatments, and such compounds are still collected, refined and screened for potential drugs today, sometimes being identified from local ‘folk medicine’ practices. By identifying the active ingredients of natural extracts used in traditional medicine, chemists can then synthesize modified forms that may be even more active: this was how the analgesic aspirin was first identified as a derivative of the plant hormone salicylic acid from willow bark. As well as offering such derivatives, natural-product synthesis in organic chemistry can potentially provide a more plentiful alternative source of natural products that are available in only tiny amounts from their natural sources. Efforts to devise cheap and efficient synthetic strategies for molecules such as paclitaxel (Taxol, an anticancer agent present in the Pacific yew) and artemisinin (an anti-malarial extracted from the herb sweet wormwood, qinghao (青蒿), and recognized by the 2015 Nobel Prize for Medicine) are still on-going to satisfy global demand. Organic synthesis is about much more than making natural products: it contributes, for example, to catalysis, polymer chemistry, food science and the development of wholly synthetic drugs. Yet efforts to make complex natural products may supply a motivational testing ground for developing new synthetic techniques with broader applications. Indeed, many chemists prize the discovery of a new synthetic method above the recreation of some complex natural molecule: it is the means, not the end, that matters. The field of organic and natural-product synthesis has a strong history in China, where there is a long tradition of herbal medicine. The use of the qinghao extract for treating malaria is first recorded in AD 340, in a manual that the 2015 Nobel laureate Tu Youyou says she consulted for clues about isolating the compound in the beginning of 1970s. Some say that, in the past decade, Chinese natural-product chemistry has entered a ‘golden era’ (Zheng Q-Y and Li A. Sci China Chem 2016;59: 1059–60). Qi-Lin Zhou of Nankai University and Xiaoming Feng of Sichuan University have been at the forefront of this upsurge. Both of them have developed methods for making so-called chiral molecules: arrangements of atoms that have a handedness, so that they can exist in two mirror-image versions. Natural products typically are chiral molecules, and their biological activity may depend on having the correct handedness. The selective synthesis of chiral molecules (asymmetric synthesis) is therefore vital to natural-product chemistry, and typically involves the use of catalysts that are chiral themselves. National Science Review spoke to Zhou and Feng about their work and their perspectives on organic synthesis in China. Qi-Lin Zhou of College of Chemistry at Nankai University, China. (Courtesy of Q Zhou)

Strategies for the construction of γ-spirocyclic butenolides in natural product synthesis

2020 ◽  
Vol 18 (28) ◽  
pp. 5287-5314 ◽  
Author(s):  
Sudip Mandal ◽  
Barla Thirupathi
Keyword(s):  
Natural Products ◽  
Natural Product ◽  
Stereoselective Synthesis ◽  
Natural Product Synthesis ◽  
Antitumor Activities ◽  
Model Compounds ◽  
Anti Inflammatory

This review describes the stereoselective synthesis of a γ-spirocyclic containing natural products or model compounds showing phytotoxic, antibiotic, anti-inflammatory, antiviral, antimicrobial, cytotoxic, and antitumor activities.

Recent applications of asymmetric organocatalytic annulation reactions in natural product synthesis

2021 ◽  
Author(s):  
Nengzhong Wang ◽  
Zugen Wu ◽  
Junjie Wang ◽  
Nisar Ullah ◽  
Yixin Lu
Keyword(s):  
Natural Products ◽  
Natural Product ◽  
Natural Product Synthesis ◽  
Natural Products Synthesis

A comprehensive and updated summary of asymmetric organocatalytic annulation reactions is presented; in particular, the applications of these annulation strategies to natural products synthesis are highlighted.

scholarly journals Applications of the Horner-Wadsworth-Emmons olefination in modern natural product synthesis

Synthesis ◽  
2021 ◽  
Author(s):  
Dávid Roman ◽  
Maria Sauer ◽  
Christine Beemelmanns
Keyword(s):  
Natural Products ◽  
Natural Product ◽  
Natural Product Synthesis ◽  
Reaction Conditions ◽  
Comprehensive Review ◽  
Modern Natural ◽  
Key Steps ◽  
Synthetic Approaches

Here, we have summarized more than 30 representative natural product syntheses published in 2015 to 2020 that employ one or more Horner-Wadsworth-Emmons (HWE) reactions. We comprehensively describe the applied phosphonate reagents, HWE reaction conditions and key steps of the total synthetic approaches. Our comprehensive review will support future synthetic approaches and serve as guideline to find the best HWE conditions for the most complicated natural products known

14 Electrochemistry in Natural Product Synthesis

2022 ◽  
Author(s):  
K. Lam ◽  
M. C. Leech ◽  
A. J. J. Lennox
Keyword(s):  
Natural Products ◽  
Natural Product ◽  
Redox Reactions ◽  
Natural Product Synthesis ◽  
Reaction Type ◽  
Multistep Synthesis ◽  
Reaction Solution ◽  
Electrochemical Redox ◽  
Synthetic Methodologies ◽  
Unique Ability

The multistep synthesis of natural products has historically served as a useful and informative platform for showcasing the best, state-of-the-art synthetic methodologies and technologies. Over the last several decades, electrochemistry has proved itself to be a useful tool for conducting redox reactions. This is primarily due to its unique ability to selectively apply any oxidizing or reducing potential to a sufficiently conductive reaction solution. Electrochemical redox reactions are readily scaled and can be more sustainable than competing strategies based on conventional redox reagents. In this chapter, we summarize the examples where electrochemistry has been used in the synthesis of natural products. The chapter is organized by the reaction type of the electrochemical step and covers both oxidative and reductive reaction modes.

scholarly journals Catalytic Asymmetric Intramolecular Darzens Reaction of 2-Halomalonate Derivatives

2019 ◽  
Vol 14 (10) ◽  
pp. 1934578X1988440
Author(s):  
Kenichi Kobayashi ◽  
Kosaku Tanaka ◽  
Momoko Suzuki ◽  
Hiroshi Kogen
Keyword(s):  
Natural Products ◽  
Natural Product ◽  
Phase Transfer ◽  
Building Blocks ◽  
Natural Product Synthesis ◽  
Darzens Reaction ◽  
Phase Transfer Catalysts ◽  
Catalytic Asymmetric

A catalytic asymmetric intramolecular Darzens reaction of 2-halomalonate derivatives was developed for the enantioselective preparation of chiral building blocks for epoxide-containing natural products. Among the screened catalysts, some phase-transfer catalysts gave the desired epoxide in moderate enantioselectivity, albeit in low yield. The epoxide product would be useful as versatile chiral building blocks for natural product synthesis.

scholarly journals Directed aromatic functionalization in natural-product synthesis: Fredericamycin A, nothapodytine B, and topopyrones B and D

2011 ◽  
Vol 7 ◽  
pp. 1475-1485 ◽  
Author(s):  
Charles Dylan Turner ◽  
Marco A Ciufolini
Keyword(s):  
Natural Products ◽  
Biological Activity ◽  
Natural Product ◽  
Natural Product Synthesis ◽  
Fredericamycin A

This is a review of our efforts toward the synthesis of a group of natural products that display noteworthy biological activity: Fredericamycin A, nothapodytine B, and topopyrones B and D. In each case, directed aromatic functionalization methodology greatly facilitated the assembly of the key molecular subunits.

Alkynyl Prins and Alkynyl Aza-Prins Annulations: Scope and Synthetic Applications

Synthesis ◽  
2020 ◽  
Vol 52 (14) ◽  
pp. 1991-2007 ◽  
Author(s):  
Alison J. Frontier ◽  
Shukree Abdul-Rashed ◽  
Connor Holt
Keyword(s):  
Natural Products ◽  
Small Molecules ◽  
Natural Product ◽  
Natural Product Synthesis ◽  
Pericyclic Reactions ◽  
Prins Reaction ◽  
Prins Cyclization ◽  
Synthetic Utility ◽  
Cascade Processes ◽  
Saturated Heterocycles

This review focuses on alkynyl Prins and alkynyl aza-Prins cyclization­ processes, which involve intramolecular coupling of an alkyne with either an oxocarbenium or iminium electrophile. The oxocarbenium or iminium species can be generated through condensation- or elimination-type processes, to achieve an overall bimolecular annulation that enables the synthesis of both oxygen- and nitrogen-containing­ saturated heterocycles with different ring sizes and substitution patterns. Also discussed are cascade processes in which alkynyl Prins heterocyclic adducts react to trigger subsequent pericyclic reactions, including [4+2] cycloadditions and Nazarov electrocyclizations, to rapidly construct complex small molecules. Finally, examples of the use of alkynyl Prins and alkynyl aza-Prins reactions in the synthesis of natural products are described. The review covers the literature through the end of 2019.1 Introduction1.1 Alkyne-Carbonyl Coupling Pathways1.2 Coupling/Cyclization Cascades Using the Alkynyl Prins Reaction2 Alkynyl Prins Annulation (Oxocarbenium Electrophiles)2.1 Early Work2.2 Halide as Terminal Nucleophile2.3 Oxygen as Terminal Nucleophile2.4 Arene as Terminal Nucleophile (Intermolecular)2.5 Arene Terminal Nucleophile (Intramolecular)2.6 Cyclizations Terminated by Elimination3 Synthetic Utility of Alkynyl Prins Annulation3.1 Alkynyl Prins-Mediated Synthesis of Dienes for a [4+2] Cyclo­- addition­-Oxidation Sequence3.2 Alkynyl Prins Cyclization Adducts as Nazarov Cyclization Precursors3.3 Alkynyl Prins Cyclization in Natural Product Synthesis4 Alkynyl Aza-Prins Annulation4.1 Iminium Electrophiles4.2 Activated Iminium Electrophiles5 Alkynyl Aza-Prins Cyclizations in Natural Product Synthesis6 Summary and Outlook

Sign in / Sign up

Export Citation Format

Share Document