Article
Chemistry, Multidisciplinary
Wen-Lei Xu, Wei-Ming Zhao, Ru-Xia Zhang, Jie Chen, Ling Zhou
Summary: The translation introduces a new and efficient method for synthesizing axially chiral aryl-C3-benzoindoles, explaining the success of the strategy in detail.
Article
Chemistry, Multidisciplinary
Kazutaka Shibatomi
Summary: This paper summarizes our recent efforts in the enantioselective organocatalytic synthesis of chiral halogenated compounds. The discussion includes enantioselective alpha-halogenation of aldehydes, decarboxylative chlorination of beta-keto acids, and enantioselective C-C bond formation at the trifluoromethylated prochiral carbon to yield organohalides with chlorinated, fluorinated, or trifluoromethylated chiral stereogenic centers. Common organocatalysts such as Jorgensen-Hayashi catalyst and cinchona alkaloid-derivatived catalyst were applied, and novel chiral amine catalysts were developed for these reactions. Stereospecific derivatizations of the chiral halogenated compounds via nucleophilic substitution are also discussed, resulting in the synthesis of many novel chiral compounds that have not been reported before, even as racemates.
Article
Chemistry, Multidisciplinary
Kai Yang, Yanfei Mao, Jie Xu, Hao Wang, Yong He, Wangyang Li, Qiuling Song
Summary: An atroposelective Miyaura borylation of bromoarenes with unsymmetrical diboron reagents has been reported for the direct catalytic synthesis of optically active atropisomeric arylborons. This reaction exhibits broad substrate scope, high yields, and good enantioselectivities in producing axially chiral arylborons.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Organic
Xi Gao, Chengwen Li, Li Chen, Xin Li
Summary: A highly enantioselective arylation reaction of 3-aryl-5-aminopyrazoles and quinone derivatives was achieved using a chiral phosphoric acid catalyst under mild conditions. The reaction showed a broad scope in terms of both arylation reaction partners and produced axially chiral arylpyrazoles with high yields (up to 95%) and enantioselectivity (99%). The reaction was proven to be efficient, as the catalyst loadings could be reduced to 1 mol % while maintaining enantioselectivity. Moreover, the synthetic utility of the protocol was demonstrated through gram-scale reaction and product transformation.
Article
Chemistry, Multidisciplinary
Shengli Huang, Haojun Wen, Yuhong Tian, Pengfei Wang, Wenling Qin, Hailong Yan
Summary: This study presents an effective method for the enantioselective preparation of polychiral compounds by intramolecular introduction of multiple stereogenic elements using organocatalysis. The compounds synthesized show potential applications in optoelectronic materials and heavy metal ion detection, as indicated by their optical properties and Ru3+-induced fluorescence responses.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Ankit Yadav, Mamta Gill, Vinod K. Singh
Summary: The asymmetric synthesis of an unprecedented exocyclic dihydronaphthalene and an axially chiral naphthalene chalcone has been reported. Good to excellent asymmetric induction is achieved through the unusual formation of exocyclic dihydronaphthalene, which is crucial for ensuring axial chirality. This is the first report of exocyclic molecules enabling the synthesis of axially chiral chalcones via stepwise asymmetric vinylogous domino double-isomerization using secondary amine catalysis.
Article
Chemistry, Multidisciplinary
Cong-Shuai Wang, Qi Xiong, Hui Xu, Hao-Ran Yang, Yanfeng Dang, Xiu-Qin Dong, Chun-Jiang Wang
Summary: A novel organocatalytic method for the synthesis of axially chiral N,N'-pyrrolylindoles based on o-alkynylanilines has been successfully developed using chiral phosphoric acid as the catalyst. This strategy allows for the efficient and selective synthesis of N,N'-pyrrolylindoles with excellent yields and enantioselectivity. Preliminary biological activity studies show that these compounds exhibit promising cytotoxicity against various cancer cell lines.
Article
Chemistry, Organic
Linan Hou, Sheng Zhang, Ji Ma, Haiyu Wang, Tienan Jin, Masahiro Terada, Ming Bao
Summary: An organocatalytic atroposelective strategy for the construction of axially chiral compounds containing benzimidazole and quinoline rings is introduced. The reaction of 2-alkynylbenzimidazoles with ortho-aminophenylketones proceeds smoothly in the presence of chiral phosphoric acid, resulting in axially chiral heterobiaryls with good yields and enantioselectivities. This paper presents the first example of combining benzimidazole and quinoline rings at the 2- and 3-positions, respectively, into axially chiral heterobiaryls using this new strategy.
Article
Chemistry, Multidisciplinary
Danijel Glavac, Matija Gredicak
Summary: This study describes the synthesis of enantioenriched Betti base precursors containing a congested quaternary stereocenter. In a chiral phosphoric acid-catalyzed reaction, a series of in situ generated isoindolinone-derived ketimines and phenol derivatives yield products with good to excellent yields and moderate enantioselectivities. Conversion of the obtained products into chiral Betti bases while retaining optical purity is demonstrated.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Organic
Eider Dunabeitia, Aitor Landa, Rosa Lopez, Claudio Palomo
Summary: The study demonstrates the capability of bicyclic acylpyrrol lactims to act as pronucleophiles and form carbon-carbon bonds under organocatalytic conditions, leading to the synthesis of chiral pyrrolodiketopiperazines. The use of ureidoaminal-derived Bronsted bases in the Michael addition to nitroolefins allows for the generation of heterocyclic scaffolds with a high degree of skeletal diversity.
Article
Chemistry, Organic
Chenguang Yu, Peng Ji, Yueteng Zhang, Xiang Meng, Wei Wang
Summary: This method utilizes a cascade cocatalysis strategy to achieve the easy construction of chiral gamma, gamma-disubstituted butenolides, showing good generality and effectiveness.
Article
Chemistry, Organic
Yuhong Tian, Fengdi Wu, Shiqi Jia, Xiangnan Gong, Hui Mao, Pengfei Wang, Wenling Qin, Hailong Yan
Summary: An organocatalytic asymmetric protocol for constructing tetrasubstituted carbon stereocenters with three heteroatoms is reported. The reaction proceeds via an enantioselective intramolecular cyclization reaction of vinylidene ortho-quinone methide (VQM) with imidates to form pentacyclic heterocycles. The resulting tetrasubstituted carbon center is stable under high temperatures and conditions for further transformations.
Article
Chemistry, Physical
Shihui Luo, Jun (Joelle) Wang
Summary: In Angewandte Chemie, Wang, Song, and co-workers proposed a new and practical organocatalysis method to synthesize axially chiral pyrazole-based phosphorus scaffolds. They achieved the central-to-axial chirality conversion in the Huisgen-type cycloaddition reaction by using a dipeptide-phosphonium salt catalyst with very low catalyst loading (1 mol %).
Article
Chemistry, Organic
Yiran Mo, Xuehuan Zhang, Yongqi Yao, Cong Duan, Ling Ye, Zhichuan Shi, Zhigang Zhao, Xuefeng Li
Summary: A sulfa-Michael/aldol/lactonization cascade reaction has been established to construct isotetronic acid-fused thiochromanes in a highly stereoselective fashion (>= 11:1 dr, 35-98% ee). The tricyclic products were obtained in 35-99% isolated yields in the presence of a bifunctional squaramide. Three reactive sites of beta,gamma-unsaturated alpha-ketoester, including the less-explored ester carbonyl group, were sequentially utilized to construct two fused heterocycles in a one-pot operation.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Pengfei Luo, Jun Dai, Ronghua Ye, Lei Zhu, Yu-Hua Deng, Fangzhi Peng, Zhihui Shao
Summary: In this study, chiral acyclic secondary aminocatalysts are developed to address the challenge of asymmetric reactions involving acetaldehyde. These catalysts exhibit unique reactivity and selectivity, improving the activity and enantioselectivity of the reactions.
CELL REPORTS PHYSICAL SCIENCE
(2022)
Review
Biochemical Research Methods
Pedro A. M. M. Varandas, Alexander J. A. Cobb, Marcela A. Segundo, Eduarda M. P. Silva
BIOCONJUGATE CHEMISTRY
(2020)
Article
Chemistry, Multidisciplinary
Daniel Townsend, Kenneth Shankland, Alex Weymouth-Wilson, Zofia Komsta, Tim Evans, Alexander J. A. Cobb
CHEMISTRY-A EUROPEAN JOURNAL
(2020)
Article
Chemistry, Multidisciplinary
Rossana Fanelli, Denes Berta, Tamas Foldes, Edina Rosta, Robert Andrew Atkinson, Hans-Joerg Hofmann, Kenneth Shankland, Alexander J. A. Cobb
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2020)
Article
Chemistry, Organic
Daniel Townsend, Kenneth Shankland, Alex Weymouth-Wilson, Zofia Komsta, Tim Evans, Alexander J. A. Cobb
TETRAHEDRON LETTERS
(2020)
Article
Biochemistry & Molecular Biology
Priyanka Parijat, Laszlo Kondacs, Alexander Alexandrovich, Mathias Gautel, Alexander J. A. Cobb, Thomas Kampourakis
Summary: Current therapeutic interventions for heart disease and heart failure are insufficient and associated with side effects. Research targeting sarcomeric proteins and identifying small molecule effectors for cardiac thin filament activation pathway have shown potential, with fingolimod identified as a new lead compound for heart failure therapeutics.
ACS CHEMICAL BIOLOGY
(2021)
Article
Chemistry, Organic
Conor Dean, Stefan Roesner, Sundaram Rajkumar, Guy J. Clarkson, Matthew Jones, Michael Shipman
Summary: This study presents a strategy for drug discovery by creating sp(3)-rich, non-planar scaffolds using stereo-controlled reactions to generate 1,2-diazetidines. The resulting chemical library is characterized by significant sp(3)-character with nitrogen substituents in an anti-configuration.
Article
Chemistry, Organic
Jamie S. Sweet, Sundaram Rajkumar, Paul Dingwall, Peter C. Knipe
Summary: This research developed a novel synthetic approach to generate a library of axially chiral N-aryl quinolinium salts inspired by naturally occurring molecules, with enantiopurities up to 93% ee obtained via a four-step route. The axial stereochemistry was controlled through an enantioselective ring-closing Buchwald-Hartwig coupling reaction. The structure and properties of the salts were examined by various methods, revealing high rotational barriers and solvatochromic behavior.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Applied
Laura A. Bryant, Kenneth Shankland, Hannah E. Straker, Callum D. Johnston, Nicholas R. Lees, Alexander J. A. Cobb
Summary: The article describes a rare organocatalytic intramolecular cyclization of resorcinols with a high enantioselectivity using a specific organocatalyst. The obtained bicyclic resorcinols show excellent utility in the synthesis of cannabinoid-like compounds, and exhibit anticonvulsant activity.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Qi Lin, Hao Lan, Chunmiao Ma, Ryan T. Stendall, Kenneth Shankland, Rebecca A. Musgrave, Peter N. Horton, Carsten Baldauf, Hans-Joerg Hofmann, Craig P. Butts, Manuel M. Mueller, Alexander J. A. Cobb
Summary: We present the first structures of an unusual helix formed by a heteromeric sequence of alpha- and delta-amino acids and demonstrate its application in catalysis. The helix formation is driven by intramolecular hydrogen bonds, but we also observed an apolar interaction that stabilizes one type of helix over another. This unique stabilization enables the alpha-residues to engage in bifunctional catalysis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Pharmacology & Pharmacy
Thomas Hibbard, Hannah Mitchell, Yoonha Kim, Kenneth Shankland, Hisham Al-Obaidi
Summary: The aim of this study was to investigate inhaled formulations of progesterone through spray drying and analyze how spray drying affects the physicochemical properties of progesterone. X-ray diffraction, spectroscopy, and thermal analysis were used to characterize the formulations. The addition of HPMCAS was shown to increase the solubility of progesterone and temporarily enable a supersaturated state. Additionally, spray drying improved the inhalation performance of progesterone. Therefore, HPMCAS is suggested as a suitable excipient to improve the solubility and inhalation properties of spray-dried progesterone formulations.
EUROPEAN JOURNAL OF PHARMACEUTICS AND BIOPHARMACEUTICS
(2023)
Article
Chemistry, Multidisciplinary
Mark J. Spillman, Norman Shankland, Kenneth Shankland
Summary: This paper describes an effective and efficient method for dealing with ring systems whose conformations are not known in advance during crystal structure determination from powder diffraction data. The method can also be applied to compounds containing multiple centers of unknown chirality.
Article
Chemistry, Multidisciplinary
Elena A. Kabova, Charles D. Blundell, Christopher A. Muryn, George F. S. Whitehead, Inigo J. Vitorica-Yrezabal, Marta J. Ross, Kenneth Shankland
Summary: This article presents a method for routine crystal structure determination using powder X-ray diffraction data from a laboratory-based single-crystal diffractometer on very small amounts of crystalline material (typically 0.1 mg or less). The method has successfully solved structures of various levels of molecular and crystallographic complexity.
Article
Chemistry, Multidisciplinary
Toyah M. C. Warnock, Sundaram Rajkumar, Matthew P. Fitzpatrick, Christopher J. Serpell, Paul Dingwall, Peter C. Knipe
Summary: This study presents a new class of chiral cyclic trimers and tetramers formed by macrocyclisation of open-chain foldamer precursors. Structural characterisation is achieved via X-ray and DFT, demonstrating near-planar conformation in tetramers and a shallow bowl-like shape in trimers. A proof-of-concept experiment is conducted to show the macrocycles' capacity for cation binding.
Article
Chemistry, Multidisciplinary
Mark J. Spillman, Kenneth Shankland
Summary: By combining local and global optimization, and using GPU to accelerate calculations, this approach successfully solved two challenging crystal structures and improved the frequency of obtaining solutions. With complex crystal structures being increasingly generated in polycrystalline form, this method represents a significant advancement in structure determination capabilities.
Article
Chemistry, Multidisciplinary
Conor Dean, Sundaram Rajkumar, Stefan Roesner, Nessa Carson, Guy J. Clarkson, Martin Wills, Matthew Jones, Michael Shipman
Article
Chemistry, Multidisciplinary
Alexander M. Prophet, Kritanjan Polley, Gary J. Van Berkel, David T. Limmer, Kevin R. Wilson
Summary: The oxidation kinetics of iodide by ozone at the air-water interface is studied in single microdroplets. Molecular simulations and kinetic modeling are used to understand the underlying multiphase mechanism.
Article
Chemistry, Multidisciplinary
Rong Zhang, Jiajing Lan, Fei Wang, Shumei Chen, Jian Zhang
Summary: By utilizing 1,1'-ferrocene dicarboxylic acid as a chelating and surface protection ligand, we have synthesized multi-nuclear indium oxide clusters with varying nuclear sizes, including heptanuclear and thirteen-nuclear clusters. These clusters possess labile coordination sites, allowing for structural modification and self-assembly, resulting in the formation of various cluster structures.
Article
Chemistry, Multidisciplinary
Hui Wang, Hui Liu, Mingsen Wang, Jiaheng Hou, Yongjun Li, Yuancheng Wang, Yingjie Zhao
Summary: Two supramolecular complexes were prepared using CBs and M1, and their single-crystal structures were analyzed by SCXRD. The unexpected 1:2 self-assembly structure between M1 and CB[8] was discovered for the first time. These complexes exhibit unique photophysical properties and provide valuable information about the structure and photophysical properties of supramolecular complexes.
Article
Chemistry, Multidisciplinary
Chang-Hee Lee, Sookil Park, Sanggil Kim, Ji Young Hyun, Hyun Soo Lee, Injae Shin
Summary: The epidermal growth factor receptor (EGFR) is a cell-surface glycoprotein involved in cell proliferation and tumor development. This study used a fluorescently labeled EGFR to investigate its time-dependent endocytosis in live cells and found that appended glycans affect EGFR internalization. Additionally, the study detected sialic acid residues attached to EGFR on the live cell surface using FRET-based imaging. This research provides valuable insights into the cellular functions of EGFR.
Article
Chemistry, Multidisciplinary
Subhankar Sahu, Lokesh Kumar, Sumita Das, Dipti Gupta, Ruchi Anand
Summary: This study proposes a strategy that combines organic electronics with biosensor scaffolds to create a compact device for monitoring environmental aromatic pollution. By coupling biosensing protein MopR with an organic electrochemical transistor (OECT), a sensor module capable of efficient detection of phenol was designed. Exclusive phenol detection with minimal loss of sensitivity could be achieved in complex pollutant mixtures and real environmental samples.
Review
Chemistry, Multidisciplinary
Changseok Lee, Hyung-Joon Kang, Sungwoo Hong
Summary: The formation of C-N bonds through hydroamination reactions catalyzed by nickel hydrides has been a topic of recent interest. This approach offers a way to efficiently transform a variety of alkene and alkyne substrates into compounds enriched with C-N bonds. The review provides a concise overview of the underlying reaction mechanisms and aims to stimulate further progress in NiH-catalytic techniques and catalyst design.
Article
Chemistry, Multidisciplinary
Yueci Wu, Lu-Lu Sun, Hai-Hao Han, Xiao-Peng He, Weiguo Cao, Tony D. James
Summary: Drug-induced liver injury (DILI) is a common cause of acute liver failure in the USA and Europe, but most cases can be recovered or prevented by discontinuing the offending drug. Recent research has found that peroxynitrite (ONOO-) can be used as a potential indicator for early diagnosis of DILI, and there is an urgent need to establish a method to detect and track peroxynitrite in DILI cases. In this study, a FRET-based nano fluorescent probe CD-N-I was developed, which showed high selectivity and sensitivity in detecting peroxynitrite. The probe successfully detected exogenous peroxynitrite in live cells and endogenous peroxynitrite in APAP-induced liver injury of HepG2 cells.
Article
Chemistry, Multidisciplinary
Dmitry L. Lipilin, Mikhail O. Zubkov, Mikhail D. Kosobokov, Alexander D. Dilman
Summary: This article describes a direct photocatalytic method for the thiolation of unprotected acids, which was previously challenging. By using a thionocarbonate reagent with an N-O bond, the efficient conversion of carboxylic acids to thiols is achieved.
Article
Chemistry, Multidisciplinary
Jason Malenfant, Lucille Kuster, Yohann Gagne, Kouassi Signo, Maxime Denis, Sylvain Canesi, Mathieu Frenette
Summary: Raman microscopy can reveal compound-specific vibrational fingerprints without sample preparation. The combination of efficient theoretical calculations and a user-friendly software can accurately predict peak positions and provide match scores to assist with structure determination.
Article
Chemistry, Multidisciplinary
Jayoh A. Hernandez, Paul S. Micus, Sean Alec Lois Sunga, Luca Mazzei, Stefano Ciurli, Gabriele Meloni
Summary: Essential trace metals play crucial roles in the survival and virulence of bacterial pathogens. Helicobacter pylori requires nickel for colonization and persistence in the stomach, and NixA is an essential nickel transporter in this process. This study characterizes the selectivity and electrogenic nature of NixA-mediated nickel transport.
Article
Chemistry, Multidisciplinary
Tarali Devi, Kuheli Dutta, Jennifer Deutscher, Stefan Mebs, Uwe Kuhlmann, Michael Haumann, Beatrice Cula, Holger Dau, Peter Hildebrandt, Kallol Ray
Summary: This study emphasizes the importance of subtle electronic changes and secondary interactions in the stability of biologically relevant metal-dioxygen intermediates. It also shows that the role of the chloride ligand in stabilizing the Fe-III-(OOBu)-Bu-t moiety can extend to other anions, including the thiolate ligand.
Article
Chemistry, Multidisciplinary
Jacqueline R. Santhouse, Jeremy M. G. Leung, Lillian T. Chong, W. Seth Horne
Summary: By studying the folding kinetics and mechanism of the BdpA sequence, researchers found that altering the backbone connectivity can affect protein folding. This suggests that protein mimetic chains have a significant degree of plasticity in transitioning between unfolded and folded states.
Article
Chemistry, Multidisciplinary
Divanshu Gupta, Ralf Einholz, Holger F. Bettinger
Summary: This study presents the first direct spectroscopic evidence of a cyclic seven-membered iminoborane. Compared to linear amino-iminoboranes, this cyclic iminoborane exhibits weakened bond strength and lower Lewis acidity value. The study suggests that the reduced ring strain of cyclic iminoborane prevents nitrogen fixation but allows facile (2 + 2) cycloaddition reaction with C2H4.
Article
Chemistry, Multidisciplinary
Renny Mathew, Aniruddha Mazumder, Praveen Kumar, Julie Matula, Sharmarke Mohamed, Petr Brazda, Mahesh Hariharan, Brijith Thomas
Summary: This study reveals the packing arrangement of partially disordered nitro-perylenediimide (NO2-PDI) using a synergistic approach that combines 3D ED, ssNMR, and DFT techniques. By overcoming these challenges, this methodology opens up new avenues for material characterization, driving exciting advancements in the field.
