Article
Chemistry, Organic
Paola Marzullo, Alice Maiocchi, Giuseppe Paladino, Umberto Ciriello, Leonardo Lo Presti, Daniele Passarella
Summary: The paper presents an enantioselective total synthesis of Cannabidiol-C-4, a natural product found in Cannabis extracts. The synthesis involves the use of 3,5-dimetoxybenzaldehyde as a starting material and includes several key steps such as Corey-Bakshi-Shibata reduction, Claisen-Ireland rearrangement, and ring-closing metathesis. The synthesized compound was characterized spectroscopically and confirmed to be present in low amounts in the extracts.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Kazutoshi Tomoya, Kazuaki Komiya, Daisuke Nakajima, Nariyoshi Umekubo, Satoshi Yokoshima
Summary: A total synthesis of kopsone was achieved by stereoselective preparation of an acyclic aldehyde with a protected hydroxylamine moiety through Ireland-Claisen rearrangement and intramolecular cycloaddition of an eight-membered cyclic nitrone, forming the 2-azabicyclo[3.3.1]nonane skeleton.
Article
Chemistry, Multidisciplinary
Bin Shi, Jia-Bin Liu, Ze-Tian Wang, Liang Wang, Yu Lan, Liang-Qiu Lu, Wen-Jing Xiao
Summary: This study presents a new method for the synthesis of chiral endocyclic allenes with high efficiency and enantioselectivity, using a relay strategy that combines Pd-catalyzed [3+2] annulation and enyne-Cope rearrangement.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Zigmars Leitis, Guna Sakaine, Artis Kinens, Gints Smits
Summary: The total syntheses of three pyrrolo[1,4]benzodiazepine anticancer antibiotic family members, oxo-prothracarcin, oxotomaymycin, and boseongazepine B, were described. The syntheses utilized late-stage stereoselective olefination with modified Julia-Kocienski reagents, which could be conveniently prepared in two steps and reduced the number of linear steps. Detailed density functional theory (DFT) studies explained the stereochemical outcome of the key step.
Article
Chemistry, Applied
Camille Van Wesemael, Nicolas Brach, Mihaela Gulea, Gaelle Blond
Summary: A series of 3-allenyl benzo[b]thiophenes were synthesized through a gold(I)-catalyzed domino reaction. The process involves a 5-endo-dig cyclization with C S bond formation and consecutive S-to-C propargyl migration via [3,3]-sigmatropic Claisen rearrangement. Various fused O-heterocycles can be obtained from a substrate bearing a 3-butynol moiety via intramolecular hydroalkoxylation. The gold-mediated 1,3-migration involving allenyl to propargyl rearrangement is also described.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Ramon Fraga, Kateryna Len, Regis Lutzing, Gilles Laverny, Julian Loureiro, Miguel A. Maestro, Natacha Rochel, Enrique Rodriguez-Borges, Antonio Mourino
Summary: The study focuses on the development of new vitamin D analogs with restricted side-chain mobility to address the hypercalcemic effects in therapeutic applications. By constructing the triene system and conducting reactions, the synthesis of target compounds was achieved and the biological activity in the binding domain of the vitamin D receptor was verified.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Organic
Michael Kohr, Niklas Papenkordt, Manfred Jung, Uli Kazmaier
Summary: This study describes a novel synthesis strategy for the naturally occurring HDAC inhibitor WF-3161. The key steps involve Matteson homologation to generate stereogenic centers in the side chain, and Pd-catalysed C-H functionalisation to connect the side chain to the peptide backbone. WF-3161 was found to be highly selective for HDAC1, with no activity observed towards HDAC6. It also exhibited high activity against the cancer cell line HL-60.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Julian Baars, Isabelle Grimm, Dirk Blunk, Joerg-Martin Neudoerfl, Hans-Guenther Schmalz
Summary: A 12-step total synthesis of the natural product dysiherbol A was achieved, revealing the need for revision of the originally proposed structure and absolute configuration. The synthesis involved key steps including Cu-catalyzed addition/enolate-trapping, Au-catalyzed double cyclization, and late installation of the C5-bridgehead methyl group. Spectroscopic measurements confirmed the identity of the synthetic compound with the natural product but with an opposite molecular rotation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Zahra Khademi, Majid M. Heravi
Summary: The Claisen condensation is a base-mediated reaction that generates alpha,beta-keto ester by reacting an ester with a molecule containing alpha-hydrogen atom. This review focuses on the applications of Claisen condensation in the total synthesis of natural products, covering relevant literature up to the beginning of 2021.
Article
Chemistry, Multidisciplinary
Yuichiro Kawamoto, Naoki Noguchi, Toyoharu Kobayashi, Hisanaka Ito
Summary: The total synthesis of lucidumone (1), a Ganoderma meroterpenoid, was accomplished in racemic form via a one-pot preparation of the tetracyclic core skeleton using Claisen rearrangement followed by an intramolecular aldol reaction. The enantioselective total synthesis of 1 was also achieved through a chiral transfer strategy in the Claisen rearrangement.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Yannick Linne, Elisa Bonandi, Christopher Tabet, Jan Geldsetzer, Markus Kalesse
Summary: The first total synthesis of chondrochloren A was achieved using a 1,2-metallate rearrangement addition as an alternative to the Nozaki-Hiyama-Kishi reaction. This approach not only overcomes the challenges of the polyketide segment but also provides a novel strategy for assembling polyketidal frameworks, utilizing a Z-selective cross coupling to form the Z-enamide.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Yuichiro Uchida, Bubwoong Kang, Hirosato Takikawa
Summary: We describe divergent total syntheses of isoflavanquinone natural products using a novel convergent synthetic strategy. A 3-chloro-2H-chromene was synthesized through Claisen rearrangement-cyclization cascade and coupled with three purposefully protected 2,5-dibenzyloxyarylboronic acids via Suzuki-Miyaura cross coupling, resulting in isoflavenes with benzyl-protected hydroquinone moieties. These isoflavenes were then subjected to catalytic hydrogenation and subsequent oxidation to obtain three isoflavanquinone natural products, abruquinones B, E, and P, in high overall yields. Our method enables facile total syntheses of natural isoflavanquinones, including the first syntheses of abruquinones E and P.
Article
Chemistry, Organic
Rongbiao Tong
Summary: This Account presents the use of two synthetic strategies (Phenol Oxidative Dearomatization, POD; and Fur an Oxidative Dearomatization, FOD) in the total synthesis of natural products. It focuses on how these total synthesis projects are conceived and connected from the perspective of laboratory development. Total synthesis is shown to be a connecting and inspirational point that sparks new ideas and projects.
Article
Chemistry, Applied
Rayhane Hammami, Pascale Maldivi, Christian Philouze, Sebastien Carret, Benjamin Darses, Soufiane Touil, Jean-Francois Poisson
Summary: A variety of 4-phosphinylpyrrolidin-3-ones were synthesized via a [3+2] cycloaddition reaction between aryl aldonitrones and phosphinylallenes. The products were obtained as unique 4,5-trans diastereomers in yields ranging from 47% to 80% for 23 examples. Chiral racemic allenes exhibited a moderate 2:1 to 4:1 2,5-diastereoselectivity. Under the reaction conditions, the cycloadducts undergo a rearrangement to selectively afford the corresponding pyrrolidin-3-ones. DFT calculations provided insights into the mechanism involving the homolytic cleavage of the N-O bond of the cycloadduct.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Haibo Wu, Zhiyao Zheng, Kaiheng Zhang, Johan Kajanus, Magnus J. Johansson, Armando Cordova, Jan-E. Baeckvall
Summary: A sustainable methodology for the synthesis of chiral allenes was reported using a simple and cheap cellulose supported heterogeneous nanocopper catalyst. High yields and excellent enantiospecificity were achieved for diverse 1,3-di and tri-substituted allenes, and the recycling of the catalyst was also demonstrated.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
