Article
Chemistry, Organic
Jia-Tian Lu, Yingxiao Zong, Xiaodong Yue, Junke Wang
Summary: The enantioselective synthesis of (+)-isolysergol was achieved in 18 steps with an overall yield of 11% from (2R)-(+)-phenyloxirane. Key steps included a stereoselective intramolecular 1,3-dipolar addition of nitrone with terminal olefin and a Cope elimination to form the D ring. A rhodium-catalyzed intramolecular [3 + 2] annulation of a benzene ring with alpha-imino carbenoid was designed for the late-stage synthesis of the 3,4-fused indole scaffold.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Kuei-Wei Chiu, Yu-Hsun Tseng, Ying-Xin Li, Rong-Jie Chein
Summary: In this study, a novel biomimetic synthesis of clavicipitic acid diastereomers was reported, utilizing a DDQ-mediated crossdehydrogenative coupling (CDC) reaction. The synthesis involved Suzuki coupling for prenylation and an intramolecular CDC reaction for the construction of the azepinoindole core. The trans isomer was obtained as the major product, and the two diastereomers were separable. The CDC reaction conditions were investigated, and a plausible mechanism for diastereoselectivity was proposed.
Article
Chemistry, Organic
Stephan Scheeff, Solenne Riviere, Johal Ruiz, Simon Dedenbach, Dirk Menche
Summary: The study details the full synthesis strategies for iso-archazolids and archazologs, including biomimetic conversion and multi-step synthesis. Through a series of reaction steps, the total synthesis of these potentially anticancer compounds was successfully accomplished.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Kenzo Yahata, Raphael J. Zachmann, Alois Fuerstner
Summary: After resolving all the issues surrounding the constitution and stereostructure of prorocentin through a recent total synthesis, a new approach was devised to improve the supply of this scarce marine natural product; this compound is a cometabolite of the phosphatase inhibitor okadaic acid but still lacks detailed biological profiling. The revised method starts from 2-deoxy-D-glucose; the key to success was a telescoped hemiacetal reduction/acetal cleavage and an exquisitely selective gold/Bronsted acid-cocatalyzed spiroacetalization.
Article
Chemistry, Organic
Ankush Banerjee, Tiffany A. Brisco, Zhen Zhang, Alexander A. Busse, Krissty Sumida, Myles W. Smith
Summary: Total syntheses of the 5/5-spirocyclic indoline alkaloids have been achieved via a modular approach, which are concise and highly amenable to analogue synthesis.
Article
Chemistry, Organic
Yinxin Liu, Jun Liu, Chuanfang Zhao, Yuguo Du
Summary: The stereoselective total synthesis of siladenoserinols A and D was achieved using carbohydrates as a chiral template. The key feature of this work is the construction of the medicinally privileged 6,8-DOBCO scaffold through a cascade reaction, which could facilitate bioactivity investigation of siladenoserinols.
Article
Chemistry, Organic
Shan-Shan Li, Li-Li Zhao, Min Pan, Na Feng, Bao-Qiong Li, Xiang-Zhi Zhang, Jin-Bao Peng, Ai-Jun Ma
Summary: An efficient synthesis of (+)-peniciketal B has been achieved in 15 steps from commercially available materials. A concise synthetic approach employing a cascade reaction was used to construct the benzo-fused 2,8-dioxabicyclo[3.3.1]-nonane with excellent stereoselectivity. The generality of the transformation was demonstrated by the broad scope of potential candidates for natural product synthesis and medicinal chemistry.
Article
Chemistry, Multidisciplinary
Victor-Emmanuel H. Kassin, Romain Morodo, Thomas Toupy, Isaline Jacquemin, Kristof Van Hecke, Raphael Robiette, Jean-Christophe M. Monbaliu
Summary: A scalable continuous flow process has been developed for the efficient and safe electrophilic alpha-aminohydroxylation of enolizable ketones using alpha-chloronitroso derivatives. The process showcases the economic and efficient nature of alpha-chloronitroso derivatives in transferring electrophilic synthons of hydroxylamine, allowing for the preparation of valuable molecules with high atom economy. The process features sequential modules, in-line extractions, and in-line analytical procedures to improve process control and safety, making it easily transposable to pilot scale and ideal for compound library screening in medicinal chemistry.
Article
Chemistry, Organic
Guang Tian, Yi-Chi Zhang, Chuanguang Qin, Jie Wang
Summary: Here, we present a unified strategy for the divergent total synthesis of six Elaeocarpus alkaloids in 6-10 steps from commercially available materials. This strategy involves the rapid construction of the tetrahydrobenzopyran-4-one framework through a series of reactions, including aldol/dehydration/oxa-Michael processes. Additionally, a key NbCl5-mediated intramolecular Mannich reaction is utilized to build the C ring and ensure the presence of both stereoisomers found in the natural products. Furthermore, a diversification step is achieved through the intermediacy of thioamide.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Multidisciplinary
Baochao Yang, Guang Li, Qian Wang, Jieping Zhu
Summary: An asymmetric synthesis of (+)-stephadiamine has been achieved using a series of reactions, including enantioselective dearomatizative Michael addition, reductive generation of nitrone followed by intramolecular cycloaddition, Curtius rearrangement, benzylic C-H oxidation, and diastereoselective ketone reduction.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Review
Chemistry, Multidisciplinary
Liyan Yang, Zhonglei Wang
Summary: Aflatoxins, produced by various Aspergillus fungi, are natural compounds with pentacyclic structures that pose a risk to human health. Over the past 55 years, there have been significant advancements in the total synthesis of aflatoxins, aiming to better understand their biological activity and presence in food industry samples.
FRONTIERS IN CHEMISTRY
(2021)
Article
Chemistry, Organic
Shota Iiyama, Keisuke Fukaya, Yu Yamaguchi, Ami Watanabe, Hiroaki Yamamoto, Shota Mochizuki, Ryosuke Saio, Takashi Noguchi, Takeshi Oishi, Takaaki Sato, Noritaka Chida
Summary: The total synthesis of paclitaxel is achieved through a double Rubottom oxidation of the bis(silyl enol ether) derived from a tricarbocyclic diketone, efficiently installing a bridgehead olefin and C-5/C-13 hydroxy groups in one step. Additionally, a novel Ag-promoted oxetane formation method is used to smoothly construct the tetracyclic framework of paclitaxel.
Article
Chemistry, Multidisciplinary
Ya-Jian Hu, Chen-Chen Gu, Xin-Feng Wang, Long Min, Chuang-Chuang Li
Summary: Taxol is a famous natural diterpenoid and important anticancer medicine with synthetic challenges. This study presents an asymmetric total synthesis of Taxol through a concise approach and the efficient construction of the challenging eight-membered ring. The new convergent approach allows for the creation of Taxol derivatives for further biological research.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Organic
Peng-Zhen Sheng, Lu-Lu Li, Zhi-Bin Ni, Kun Wei, Yu-Rong Yang
Summary: Cephalotine A, a newly isolated alkaloid from Cephalotaxus, was successfully synthesized enantioselectively via three crucial reactions. These involved SmI2-mediated radical cyclization of lactone and aldehyde for the final ring formation, Chang's iridium-catalyzed C-H amidation for constructing pyrrolidone stereoselectively, and Carreria's dual Ir/amine catalyzed allylation to introduce the neighboring tertiary stereocenters.
Article
Chemistry, Multidisciplinary
K. C. Nicolaou, Saiyong Pan, Yogesh Shelke, Dipendu Das, Qiuji Ye, Yong Lu, Susanta Sau, Ruiyang Bao, Stephan Rigol
Summary: A new strategy for the total synthesis of Halichondrin B was described in this study, presenting a novel approach that allows for improved syntheses of complex compounds. The method involves the reversal of sequential construction and the coupling of defined fragments to achieve a convergent pathway.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Applied
Rolande Tsafack Nguemo, Roukayatou Mbouangouere, Gabin Thierry M. Bitchagno, Roland Tchuenguem, Elise Vanessa N. Temgoua, Blanche Laure Ndontsa, James Simo Mpetga, Till Opatz, Augustin Silvere Ngouela, Pierre Tane
Summary: This study reports a new ceramide and six known compounds from the methanol extract of Lannea schimperi leaves. These metabolites were characterized using spectroscopic and spectrometric techniques and demonstrated promising radical-scavenging activity against reactive oxygen species (ROS).
NATURAL PRODUCT RESEARCH
(2022)
Article
Biochemistry & Molecular Biology
Markus Rohr, Anna Maria Kiefer, Ulrich Kauhl, Jonathan Gross, Till Opatz, Gerhard Erkel
Summary: Two new compounds were isolated from a fungus and found to inhibit the activity of the pro-inflammatory marker gene CXCL10. These compounds also interfered with multiple signaling pathways and reduced the synthesis of inflammatory mediators.
BIOLOGICAL CHEMISTRY
(2022)
Article
Chemistry, Applied
Claudie Fokou Kenmogne, Beaudelaire Kemvoufo Ponou, Blondelle Matio Kemkuignou, Jonas Kuhlborn, Roland T. Tchuenguem, Remy Bertrand Teponno, Jean Paul Dzoyem, Till Opatz, Leon Azefack Tapondjou
Summary: A new triterpenoid saponin and nine known compounds were isolated from Mimosa diplotricha. The structure of the new compound was elucidated through spectroscopic and mass spectrometric data. One of the compounds showed inhibitory activity against Proteus mirabilis and Pseudomonas aeruginosa.
NATURAL PRODUCT RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Paul Eckhardt, Quintin Elliot, Igor Alabugin, Till Opatz
Summary: In this study, the possibility of oxidation under basic conditions for cross-dehydrogenative coupling (CDC) to form three-electron bonds was explored, which allows the use of milder oxidants and avoids the formation of high-energy intermediates.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Sarah Jane Mear, Tobias Lucas, Grace P. Ahlqvist, Juliana M. S. Robey, Jule-Philipp Dietz, Pankaj Khairnar, Sanjay Maity, Corshai L. Williams, David R. Snead, Ryan C. Nelson, Till Opatz, Timothy F. Jamison
Summary: This study improved the synthesis method of bedaquiline, increasing the yield and reducing the cost, making this crucial medication more accessible to a larger number of patients.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Dennis Pollok, Luca M. Grossmann, Torsten Behrendt, Till Opatz, Siegfried R. Waldvogel
Summary: This article presents a highly versatile approach to access the Amaryllidaceae alkaloids family of natural products. Through sustainable electro-organic transformation and biomimetic synthesis, important drugs for the treatment of Alzheimer's disease can be synthesized.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Biochemistry & Molecular Biology
Anja Eckelt, Franziska Wichmann, Franziska Bayer, John Eckelt, Jonathan Gross, Till Opatz, Kerstin Jurk, Christoph Reinhardt, Klytaimnistra Kiouptsi
Summary: The study compared the effects of an ethyl hydroxyethyl cellulose (EHEC) solution with other biocompatible materials on platelet aggregation. The results showed that the EHEC solution exhibited shear-thinning behavior similar to human blood and did not enhance blood clot formation or platelet aggregation and activation, suggesting its potential as a biocompatible carrier material in blood circulation.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Plant Sciences
Gabin Thierry M. Bitchagno, Anja Schueffler, Jonathan Gross, Matthias Krumb, Pierre Tane, Till Opatz
Summary: The genus Vernonia is a valuable source of biologically active sesquiterpene lactones. This study investigates the structure, cytotoxicity, antimicrobial properties, and biosynthetic pathway of newly discovered germacranolide-like sesquiterpenoids from Vernonia tufnelliae, a medicinal plant from Cameroon. The compounds show unique structural features and exhibit potential for medicinal applications. The study also confirms the presence of known compounds in V. tufnelliae and provides insights into their stereochemistry. This research contributes to the understanding of the chemistry and biology of V. tufnelliae.
JOURNAL OF NATURAL PRODUCTS
(2022)
Editorial Material
Chemistry, Multidisciplinary
Luca Marius Grossmann, Vera Beier, Lea Duttenhofer, Laura Lennartz, Till Opatz
Summary: The cover of this issue features the electrochemical coupling of amines and carboxylic acids to form amides.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Biochemistry & Molecular Biology
Lena Katharina Mueller-Heupt, Nadine Wiesmann-Imilowski, Sofia Schroeder, Jonathan Gross, Pablo Cores Ziskoven, Philipp Bani, Peer Wolfgang Kaemmerer, Eik Schiegnitz, Anja Eckelt, John Eckelt, Ulrike Ritz, Till Opatz, Bilal Al-Nawas, Christopher Synatschke, James Deschner
Summary: Periodontitis is a chronic inflammatory disease that leads to tooth loss and significantly impacts global health. A hyaluronic acid-based dispersion with controlled oxygen delivery shows potential as a treatment for periodontitis. In vitro and in vivo studies demonstrate the biocompatibility, antimicrobial activity against Porphyromonas gingivalis, and angiogenesis enhancement of the developed oxygen-releasing dispersion. This suggests the potential of oxygen-releasing biomaterials for periodontal tissue regeneration.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Infectious Diseases
Lena Katharina Mueller-Heupt, Anja Eckelt, John Eckelt, Jonathan Gross, Till Opatz, Nadine Kommerein
Summary: Periodontitis, caused by bacterial dysbiosis, is a common global disease associated with anaerobic bacterial colonization. A study investigated the potential of calcium peroxide (CaO2) as an antimicrobial agent for treating periodontitis. It was found that CaO2 selectively inhibited the growth and viability of Porphyromonas gingivalis but had little effect on Streptococcus oralis, indicating its potential for selectively affecting both planktonic bacteria and mono-species biofilms of P. gingivalis.
Article
Chemistry, Applied
Tobias Lucas, Jule-Philipp Dietz, Flavio S. P. Cardoso, David R. Snead, Ryan C. Nelson, Kai O. Donsbach, B. Frank Gupton, Till Opatz
Summary: An efficient gram-scale synthesis of the antituberculosis agent pretomanid was achieved using straightforward chemistry, mild reaction conditions, and readily available starting materials. The synthesis involved investigating different protecting groups on the glycidol moiety and utilized a linear three-step process with up to 40% isolated yield. Notably, the deprotection and cyclization steps were performed in a one-pot fashion without the need for hazardous materials or steps.
ORGANIC PROCESS RESEARCH & DEVELOPMENT
(2023)
Article
Chemistry, Multidisciplinary
Johannes Rocker, Till Opatz
Summary: This study demonstrates the use of a readily accessible polyazahelicene as a strongly reducing metal-free alternative to commonly used precious metal-based photoredox catalysts. An improved two-step synthesis of the catalyst is described, and its photophysical properties as a photoredox catalyst are evaluated. The polyazahelicene exhibits comparable activity to an iridium-based catalyst in two double radical light-driven multicomponent reactions.
ACS ORGANIC & INORGANIC AU
(2022)
Article
Chemistry, Organic
Paulo Eliandro da Silva Junior, Shaiani Maria Gil de Melo, Murilo Helder de Paula, Ricardo Vessecchi, Till Opatz, James E. H. Day, A. Ganesan, Flavio da Silva Emery
Summary: This article discusses the reactivity of 6-azaindazole and 2,6-naphthyridine, which are important in fragment-based drug discovery. The article introduces selective functionalization methods for pyridone and pyrazole, as well as a new method for selective functionalization of heterocycle 1.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Cintia M. C. F. Lima, Till Opatz, Mauricio M. Victor
Summary: 7-Azaisoindigo is an important member of the bisoxindole family with various biological activities and potential in electronic material synthesis. However, there is limited research on its preparation and few derivatives have been reported. This study successfully synthesized six new substituted 7-azaisoindigos using an acid-catalyzed coupling reaction between 7-azaoxindole and substituted isatins with ZrCl4 as a catalyst in refluxing ethanol.
RESULTS IN CHEMISTRY
(2022)
