Article
Chemistry, Multidisciplinary
Lukas Englert, Uwe Schmidt, Michael Domling, Max Passargus, Tom E. Stennett, Alexander Hermann, Merle Arrowsmith, Marcel Harterich, Jonas Mussig, Alexandra Phillipps, Dominic Prieschl, Anna Rempel, Felix Rohm, Krzysztof Radacki, Fabian Schorr, Torsten Thiess, J. Oscar C. Jimenez-Halla, Holger Braunschweig
Summary: Reactions of terminal acetylenes with doubly Lewis base-stabilised diborenes exhibit distinct outcomes based on temperature and ligand properties, involving either cycloaddition or hydroalkynylation. Phosphine-stabilised diborenes undergo exclusively cycloaddition, leading to significant molecular rearrangement.
Article
Chemistry, Multidisciplinary
Jian Song, Wen-Hua Zheng
Summary: Despite the widespread use of boronic acids in catalysis, the development of efficient chiral boronic acids remains challenging. In this study, a rational design and a concise synthesis of new C2-symmetric disubstituted boronic acids, or borinic acids, were disclosed. These chiral borinic acids were found to be effective in achieving highly enantioselective desymmetrization of 2,2-disubstituted-1,3-propanediols, leading to chiral diols with a quaternary stereocenter. A range of substrates were successfully utilized in this reaction, providing chiral diols with high enantioselectivity. 11B NMR studies confirmed the presence of tetracoordinate borinate in the catalytic cycle, and a stereocontrol model was proposed.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Saswata Gupta, Siyuan Su, Yu Zhang, Peng Liu, Donald J. Wink, Daesung Lee
Summary: Metallaaromatics are a unique class of aromatic compounds incorporating one or more transition metal elements, showing distinctive structural and theoretical interests, and serving as a novel platform for new catalyst development.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Review
Chemistry, Organic
Waqar Ahmed, Vikrant Jayant, Shakeel Alvi, Nadeem Ahmed, Azeem Ahmed, Rashid Ali
Summary: The synthesis of natural products has always been a top priority for synthetic chemists worldwide. Various synthetic methodologies have been used to extract, elucidate, synthesize, and document a wide range of natural products. The synthesis of complex natural products often presents challenges that can be overcome through modification or development of new synthetic methods. Metathesis tactics, discovered unexpectedly in the 1950s and awarded the Nobel Prize in 2005, have greatly influenced and changed the landscape of total and formal synthesis. This review article provides a comprehensive detail of metathetic tools used in the synthesis of natural products from 2017 to 2019.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Julian Greb, Till Drennhaus, Moritz K. T. Klischan, Zachary W. W. Schroeder, Wolfgang Frey, Joerg Pietruszka
Summary: This article describes the enantioselective synthesis of a chiral 2,2'-biphenol building block and demonstrates its potential for the synthesis of natural products.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Gihan C. Dissanayake, Cornelius N. Ndi, Jana L. Markley, James B. Martinez, Paul R. Hanson
Summary: Two synthetic strategies involving phosphate tether-mediated one-pot sequential protocols were developed for the total synthesis of sanctolide A, a polyketide nonribosomal peptide macrolide, and the formal synthesis of its (2S)-epimer.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Mathias S. Neumann, Jan O. Jeppesen
Summary: Redox-responsive compounds, including Tetrathiafulvalene (TTF) derivatives, have been widely studied in molecular nanotechnology for their potential applications in constructing redox-active materials. However, the use of BPTTF as a building block is still limited despite its favorable properties. This study reports the synthesis and functionalization of two novel non-symmetric BPTTF building blocks, which can be obtained from specific intermediates in moderate to high yields.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Organic
Michele Retini, Francesca Bartoccini, Giovanni Zappia, Giovanni Piersanti
Summary: This article describes a new class of chiral thioureas that, in combination with 4-methoxybenzoic acid, promote enantioselective reactions. The formation of a chiral catalyst-anion complex was explored using H-1 NMR spectroscopy.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Polymer Science
Ankita Mandal, Indradip Mandal, Andreas F. M. Kilbinger
Summary: Regioselective chain transfer agents, in combination with the PA-ROMP technique, are used to synthesize narrowly dispersed heterotelechelic polymers with excellent control over molecular weight and dispersity. The chain transfer agents show high efficacy in 15 pulses of polymerization, with minimal catalyst decomposition and high degree of chain end functionalization confirmed by H-1 NMR and MALDI-ToF mass spectrometry.
Article
Chemistry, Organic
Pramod Swami, Maruti Mali, Baswaraj Dhulshette, Subhash Ghosh
Summary: The first total synthesis of the recently isolated natural product thiocladospolide A, along with its C2-epimer, was achieved in nine straightforward linear steps with a 12% overall yield. The key feature of the synthesis is the construction of the macrocyclic ring via a late-stage ring-closing metathesis reaction followed by alkene reduction.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Organic
Amit Singh Adhikari, Nilanjana Majumdar
Summary: This study reveals the unprecedented reactivity of a Grubbs catalyst in the reaction between vinyl azaarenes and alkenylnitriles under standard metathesis conditions, resulting in high-yield hydroalkylation products with no observed metathesis. The practical utility of the obtained products in useful transformations, such as the formation of cyclic iminoesters and highly challenging medium-sized carbocycles, has been demonstrated.
Article
Chemistry, Physical
Wei Zhang, Weilu Yang, Hongbing Pan, Xiaolin Lyu, Anqi Xiao, Dong Liu, Yun Liu, Zhihao Shen, Huai Yang, Xing-He Fan
Summary: Two novel organic-inorganic block molecules capable of forming sub-5-nm ordered structures were reported in this study. The sizes of the structures can be regulated by adjusting the number of chains. These block molecules have the potential for sub-5-nm nanopatterning.
Article
Polymer Science
Ankita Mandal, Indradip Mandal, Andreas F. M. Kilbinger
Summary: Single chain transfer agents are used to synthesize narrowly distributed heterotelechelic ROMP polymers in one pot, exploiting a new mechanistic and synthetic approach. The strategy allows for excellent control over molecular weight and dispersity of the resulting polymers, showcasing a straightforward and efficient method for synthesizing heterotelechelic ROMP polymers.
Article
Chemistry, Organic
Woraluk Mansawat, Phanomsak Yukhet, Worawan Bhanthumnavin, Oliver Reiser, Tirayut Vilaivan
Summary: The use of C-2-symmetrical chiral amino alcohol ligands in combination with CuCl2 has been shown to be effective for the asymmetric acylation of dI-hydrobenzoins, with up to 99% ee obtained for the monoacylated products.
Article
Polymer Science
Shoichiro Uchiyama, Taichi Sotani, Toshiko Mizokuro, Hiromitsu Sogawa, Kenneth B. Wagener, Fumio Sanda
Summary: The functionalization of polymer chain ends is a hot topic in synthetic polymer chemistry. This study demonstrates the incorporation of a platinum complex at the terminal of a polynorbornene derivative for the first time. The modified polymers exhibited enhanced absorption and photoluminescence properties compared to the unmodified polymer. The weight residues of the functionalized polymers at high temperatures were higher than the unmodified polymer.
Article
Chemistry, Organic
Nastja Riemer, Martin Riemer, Mandy Krueger, Guy J. Clarkson, Michael Shipman, Bernd Schmidt
Summary: exo-Methylene-beta-lactams were synthesized in high yields as single isomers in a two-step reaction involving a Heck-type arylation with arene diazonium salts. The Pd-catalyzed coupling reaction showed high exo-regioselectivity and E-stereoselectivity in the beta-hydride elimination step. However, coupling products with aryl iodides, triflates, or bromides were obtained only in low yields due to extensive decomposition of the starting materials at elevated temperatures.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Medicinal
Benson Oloya, Jane Namukobe, Matthias Heydenreich, Willy Ssengooba, Bernd Schmidt, Robert Byamukama
Summary: Lupeol, sesamin, trans-fagaramide, and other compounds isolated from the stem bark of Zanthoxylum leprieurii showed moderate to significant antimycobacterial activities, with trans-fagaramide potentially serving as a vital template for novel and effective tuberculosis drugs.
NATURAL PRODUCT COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Kajsa Lood, Triin Tikk, Mandy Krueger, Bernd Schmidt
Summary: The cross-metathesis reactions of four combinations of type-I olefins isoeugenol and 4-hydroxy-3-methoxystyrene with type-II olefins acrolein and crotonaldehyde were investigated. Only the combination of isoeugenol and crotonaldehyde showed useful conversions. The high reactivity of this combination was demonstrated by the synthesis of 7-methoxywutaifuranal with a 44% yield. Methylene capping was suggested as the reason for the superior performance of crotonaldehyde in these reactions.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Nanoscience & Nanotechnology
Yuhang Zhao, Radwan M. Sarhan, Alberto Eljarrat, Zdravko Kochovski, Christoph Koch, Bernd Schmidt, Wouter Koopman, Yan Lu
Summary: Bimetallic nanostructures can generate a new type of photo-enhanced nanoreactors by utilizing photo-generated heat to accelerate catalytic reactions. The study demonstrates that the photothermal conversion of Au-Pd nanorods can be improved by coating with polydopamine or TiO2, resulting in increased reaction rates.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Applied
Gaston Bravo-Arrepol, Jose Becerra, Leandro Ortiz, Jaime Cabrera-Pardo, Bernd Schmidt, Matthias Heydenreich, Alexandra Kelling, Eric Sperlich, Tomasz M. Karpinski, Cristian Paz
Summary: Furofuran lignanes, which are obtained from various plants, possess important biological activities for treating infectious diseases, inflammatory diseases, and metabolic disorders. In this study, eudesmin, a furofuran lignan, was easily isolated from Araucaria araucana knots using soxhlet extraction and cryo-crystallization. The bromination of eudesmin led to the formation of epieudesmin and its corresponding mono and di-brominated derivatives. The structures of these compounds were determined by NMR and X-ray diffraction. Furthermore, eudesmin exhibited moderate activity against Candida yeast strains, while epieudesmin and the bromine derivatives showed no activity.
NATURAL PRODUCT RESEARCH
(2023)
Article
Biochemistry & Molecular Biology
Nicole Cortez, Victor Marin, Veronica A. Jimenez, Victor Silva, Oscar Leyton, Jaime R. Cabrera-Pardo, Bernd Schmidt, Matthias Heydenreich, Viviana Burgos, Paola Duran, Cristian Paz
Summary: Fungal biotransformation is an effective and attractive method for synthesizing specific compounds with unique chemical functionality. In this study, Cladosporium antarcticum was used to produce novel drimane sesquiterpenoid alcohols with activity against Candida yeast. The compounds were obtained through high-yield reduction of polygodial and isotadeonal. The antifungal activity of the compounds was evaluated, and it was found that one of the compounds showed potent inhibitory effects against three Candida species.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Biochemistry & Molecular Biology
Victor Marin, Bryan Bart, Nicole Cortez, Veronica A. Jimenez, Victor Silva, Oscar Leyton, Jaime R. Cabrera-Pardo, Bernd Schmidt, Matthias Heydenreich, Viviana Burgos, Cristian Paz
Summary: This study identified compounds from Drimys winteri (Winteraceae) that possess antifungal activity against Candida yeast. The most active compound, polygodial, showed fungistatic activity but caused irritation to the eyes and skin. A new compound, winterdial, was also discovered with potential antifungal properties. These findings are valuable for the development of more potent and safer drugs to treat candidiasis using natural compounds as a primary source.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Organic
Patrick Sand, Bernd Schmidt
Summary: The regioselectivity of two mechanistically distinct alkenylation reactions catalyzed by in situ-formed cationic transition metal complexes was studied using N-allyl-N-phenylethenesulfonamide as a model compound. Orthogonal selectivity was observed for the Ru-catalyzed C-H-activating alkenylation with acetanilides, which occurs preferentially at the electron deficient double bond, and for a Pd-catalyzed Heck-type coupling with arene diazonium salts, which occurs preferentially at the more electron rich double bond of the N-allyl substituent.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Plant Sciences
Vaderament-Alexe Nchiozem-Ngnitedem, Eric Sperlich, Valaire Yemene Matieta, Jenifer Reine Ngnouzouba Kuete, Victor Kuete, Ejlal A. A. Omer, Thomas Efferth, Bernd Schmidt
Summary: FicucariconeD and its 4'-demethyl congener 2 are isoflavones obtained from Ficus carica fruits with a 5,7-dimethoxy-6-prenyl-substituted A-ring. They were synthesized for the first time in six steps from 2,4,6-trihydroxyacetophenone. The compounds showed no cytotoxicity against leukemia cell lines but exhibited antimicrobial activities, especially when combined with the efflux pump inhibitor PA beta N.
JOURNAL OF NATURAL PRODUCTS
(2023)
Article
Chemistry, Physical
Radwan M. M. Sarhan, Sergio Kogikoski Jr, Robin M. M. Schuermann, Yuhang Zhao, Andreas Krause, Bernd Schmidt, Ilko Bald, Yan Lu
Summary: This study presents a facile and environmentally friendly method to synthesize black gold nanoparticles via a one-step green synthesis at room temperature using commonly known precursors. The self-assembly of in situ-formed small nanoparticles followed by a fusion step creates extensive networks of nanowires, resulting in strong photothermal and surface-enhanced Raman scattering (SERS) effects. The black gold nanoparticles show potential for applications in solar energy conversion and photothermal therapy.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Plant Sciences
Benson Oloya, Jane Namukobe, Matthias Heydenreich, Willy Ssengooba, Johannes Martin, Heiko Michael Moeller, Bernd Schmidt, Robert Byamukama
Summary: Two new compounds with strong anti-mycobacterial activities were isolated from the root bark of Z. leprieurii, which could potentially serve as new and highly effective drugs for tuberculosis.
PHYTOCHEMISTRY LETTERS
(2023)
Article
Chemistry, Organic
George Kwesiga, Julia Greese, Alexandra Kelling, Eric Sperlich, Bernd Schmidt
Summary: Isoflavones were synthesized via Suzuki-Miyaura coupling using para-phenolboronic acid and para-methoxybenzene boronic acid as reactants. The optimized conditions led to higher yields of isoflavones.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Rebeca Perez, Claudia Figueredo, Viviana Burgos, Jaime R. Cabrera-Pardo, Bernd Schmidt, Matthias Heydenreich, Andreas Koch, Jennifer R. Deuis, Irina Vetter, Cristian Paz
Summary: Maqui, a tree native to Chile, is used by the Mapuche people as an anti-inflammatory agent for the treatment of digestive ailments, fever, and skin lesions. Maqui fruits are considered a superfruit with potential health benefits, including antioxidant, cardioprotective, and anti-inflammatory properties. The leaves of maqui contain alkaloids, polyphenols, and terpenes. The alkaloids, aristoteline and hobartine, were found to inhibit Na(V)1.8, a key Na-V isoform involved in pain sensation, suggesting a potential mechanism for the reported analgesic properties of maqui.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Chemistry, Multidisciplinary
Eric Sperlich, Alexandra Kelling, George Kwesiga, Bernd Schmidt
Summary: The molecular structures of three closely related isoflavones were determined and analyzed using X-ray diffraction and various analysis methods. The study found that non-covalent interactions play a crucial role in the formation of supramolecular structures and the macroscopic properties of the compounds.
Article
Chemistry, Organic
Andreas Krause, Eric Sperlich, Bernd Schmidt
Summary: Itaconic acid esters and hemiesters undergo efficient Pd-catalyzed coupling reactions with arene diazonium salts, leading to the synthesis of benzazepine-2-ones in one to two steps with high yields.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)