Article
Chemistry, Organic
Jessica E. Budwitz, Christopher G. Newton
Summary: pars-Quinones are widely used as targets and/or intermediates in various chemical and biological disciplines, highlighting the significance of efficient preparative methods. This Synpacts article provides an overview of ring forming approaches to para-hydroquinones and para-benzoquinones, concluding with our recent contribution on the development of 2,5-bis(tert-butyldimethylsilyloxy)furans as vicinal bisketene equivalents in the DieIs-Alder reaction.
Article
Chemistry, Organic
Flavie Rambaud, Regis Guillot, Valerie Alezra, Cyrille Kouklovsky
Summary: A cycloaddition-fragmentation sequence involving benzene oxide and a nitroso- or azo-dienophile was studied for the synthesis of highly substituted cyclohexene oxide derivatives. The alkyl lithium-promoted fragmentation of the cycloadducts resulted in cyclic derivatives through 1,4- or 1,2-addition of a second equivalent of the lithium reagent. The use of non-nucleophilic bases of hindered alkyl lithium reagents led to new fragmentation processes. All reactions exhibited complete stereocontrol.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Miglena K. Georgieva, A. Gil Santos
Summary: The Diels-Alder reaction is a fascinating chemical process that has been extensively studied, both in its achiral and chiral versions. In this study, the authors investigate the Diels-Alder reaction of 2'-hydroxychalcones with two dienes, catalyzed by chiral organo-boron Lewis acid complexes. The authors use theoretical methods to evaluate the proposed reaction mechanism and provide insights into the enantioselectivity and endo/exo selectivity of the reaction.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Bienfait Kabuyaya Isamura, Kevin Alan Lobb
Summary: In this manuscript, new insights into the concept of (a)synchronicity in Diels-Alder (DA) reactions are reported. The results suggest that the DA reaction transitions from a concerted mechanism to a stepwise one within a narrow window of synchronicity indices. The relative position of the global minimum of the reaction force constant with respect to the transition state (TS) is proposed as a quantifiable indicator of the (a)synchronicity in the DA reactions. Moreover, the atomic resolution of energy derivatives reveals the involvement of two inner elementary processes in the DA reaction mechanism.
Article
Chemistry, Multidisciplinary
Masao Ohashi, Dan Tan, Jiayan Lu, Cooper S. Jamieson, Daiki Kanayama, Jiahai Zhou, K. N. Houk, Yi Tang
Summary: The synthesis of cis-decalin structures using [4 + 2] cycloaddition with high stereoselectivity is challenging. In this study, we investigated the biosynthetic pathway of the fungal natural product fischerin (1) and identified a novel pericyclase, FinI, which catalyzes this reaction. The cocrystal structure of FinI, a predicted O-methyltransferase, with the product and SAM provides valuable insights into the natural formation of cis-decalin.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Julia O. Strelnikova, Alexander N. Koronatov, Nikolai Rostovskii, Alexander F. Khlebnikov, Olesya Khoroshilova, Mariya A. Kryukova, Mikhail S. Novikov
Summary: The domino reaction catalyzed by Rh-2(Piv)(4) leads to the formation of N-sulfonylated (Z)-2-(2-aminovinyl)imidazoles, providing a direct and flexible access to the desired compounds.
Article
Chemistry, Organic
Yan Jiang, Hao-Jie Ma, Xue-Long Wang, Yi Yang
Summary: A Yb(OTf)(3)-catalyzed formal (4 + 3) cycloaddition reaction was successfully achieved using donor-acceptor cyclopropanes and 3-benzylideneindoline-2-thiones as reactants. Functionalized 5,10-dihydro-2H-thiepino[2,3-b]indole derivatives were synthesized with good yields and moderate to good diastereoselectivity. This reaction represents the first (4 + 3) cycloaddition of 3-benzylideneindoline-2-thiones.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Rupkumar Khuntia, Sanat Kumar Mahapatra, Lisa Roy, Subhas Chandra Pan
Summary: An important goal in organic synthesis and medicinal chemistry is to efficiently and affordably synthesize structurally diverse and complex molecules from readily available starting materials. In this study, a protocol for the synthesis of benzofuran fused azocine derivatives and spiro-cyclopentanone benzofurans has been developed. The method involves sequential catalysis with chiral H-bonding catalyst and Lewis base catalyst. The products exhibit high yields and high stereo- and enantioselectivities.
Article
Chemistry, Multidisciplinary
Rupkumar Khuntia, Sanat Kumar Mahapatra, Lisa Roy, Subhas Chandra Pan
Summary: In this study, a new method has been developed to rapidly synthesize structurally diverse and complex molecules from easily available starting materials through catalytic reactions. Through the analysis of the mechanistic intricacies, the roles of chiral and Lewis base catalysts in the reaction have been investigated.
Article
Chemistry, Physical
Wakana Sakai, Lori Gonnet, Naoki Haruta, Tohru Sato, Michel Baron
Summary: This study theoretically explains the factors that control the mechanochemical reactivities using Diels-Alder reactions as an example. The introduction of dimensionless mechanochemical reaction constants allows for the comparison of different reactions.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2024)
Article
Chemistry, Organic
Nan-Fang Mo, Ying Zhang, Zheng-Hui Guan
Summary: An asymmetric organocatalyzed three-component Povarov reaction has been developed to construct azaspirocycles. A chiral phosphoric acid catalyst with a unique structure was highly efficient in the reaction, leading to a wide range of azaspirocycles in high yields and excellent enantioselectivities. This reaction has expanded the scope of the traditional Povarov reaction.
Article
Chemistry, Organic
Gary L. Points, Christopher M. Beaudry
Summary: Substituted carbazoles are efficiently synthesized from 3-triflato-2-pyrones and alkynyl anilines, allowing for multiple substituents with complete control of regiochemistry, resulting in complex substitution patterns. This strategy can also be applied to prepare substituted bicarbazoles and related biaryls, and has been demonstrated in the synthesis of the carbazole natural product clausine C.
Article
Chemistry, Organic
Tao Wang, Wen-Bin Wang, Yan-Ming Fu, Cheng-Feng Zhu, Lan-Jun Cheng, Yang-En You, Xiang Wu, You-Gui Li
Summary: An asymmetric double oxidative [3 + 2] cycloaddition is reported, which generates highly functionalized chiral CF3-containing spiro[pyrrolidin-3,2'-oxindole] with four contiguous stereocenters stereoselectively. This method directly constructs two C-C bonds from four C(sp3)-H bonds, and it features mild conditions, broad substrate scope, and excellent functional group compatibility.
Review
Polymer Science
Prantik Mondal, Prasanta K. Behera, Nikhil K. Singha
Summary: The concept of 'click' chemistry has been established in the field of chemistry for almost two decades, leading to the development of numerous chemical approaches with similar features. Various types of 'click' reactions are used in polymer chemistry to prepare functional polymers, and the ultrafast 'click' modification based on 1,2,4-triazoline-3,5-dione (TAD) derivatives has gained significant attention in polymer research.
PROGRESS IN POLYMER SCIENCE
(2021)
Article
Chemistry, Organic
Yan Jiang, Hao-Jie Ma, Xue-Long Wang, Yi Yang
Summary: A new compound was synthesized successfully in this study by using Yb-(OTf)(3) catalyst to react donor-acceptor cyclopropanes with sulfur-containing 4π components. The reaction showed high yields and moderate to good diastereoselectivity.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Biochemical Research Methods
Loraine Carolina Goenaga-Mafud, Yordania Matos Gamez, Carolina P. Campos, Jose Dirceu Vollet-Filho, Natalia Mayumi Inada, Cristina Kurachi, Vanderlei Salvador Bagnato
Summary: This article demonstrates the feasibility of reducing bacterial load in a kidney model by using ultraviolet-C as a germicidal agent. The results show that the bacterial load in the perfusate can be fully eliminated in less than 30 minutes of liquid circulation and irradiation. A modeling approach is used to verify the decrease in bacterial load when an organ is present in the circuit.
JOURNAL OF BIOPHOTONICS
(2022)
Article
Biochemistry & Molecular Biology
M. A. Tiburcio, A. R. Rocha, R. A. Romano, N. M. Inada, V. S. Bagnato, R. M. Carlos, H. H. Buzza
Summary: The study investigated the photosensitizing efficiency of RupPDIp against S. brasiliensis and C. albicans. Results showed that RupPDIp eliminated both fungi at <= 5.0 mu M, with green light showing the best results.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY
(2022)
Article
Dentistry, Oral Surgery & Medicine
Cesar Augusto Abreu-Pereira, Marlise Inez Klein, Carmelia Isabel Vitorino Lobo, Ana Luiza Gorayb Pereira, Claudia Carolina Jordao, Ana Claudia Pavarina
Summary: This study evaluated the effectiveness of DNase I combined with antimicrobial photodynamic therapy against biofilms formed by a fluconazole-resistant Candida albicans strain. The results showed that DNase treatment combined with aPDT could significantly reduce cell viability and the components of the biofilm.
Article
Chemistry, Organic
Aline A. N. de Souza, Aloisio de A. Bartolomeu, Timothy J. Brocksom, Timothy Noel, Kleber T. de Oliveira
Summary: The electrochemical sulfenylation reaction was investigated in both batch and continuous flow regimes, with quaternary ammonium salts identified as the best mediators. The tolerance of Boc-cysteine to the reaction protocol was noted, increasing its relevance. The methodology was found to be scalable in both batch and continuous flow conditions, offering potential for further studies involving important functional groups in organic synthesis.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Irwin A. P. Linares, Leticia P. Martinelli, Milene N. O. Moritz, Heloisa S. Selistre-de-Araujo, Kleber T. de Oliveira, Janice Rodrigues Perussi
Summary: Photodynamic Therapy (PDT) is a promising treatment that uses photosensitizers to generate reactive oxygen species and induce cell death. This study evaluated the photoactivity of four chlorins in tumor and non-tumor cell lines, and found that certain chlorins exhibited high selectivity and phototoxicity in tumor cells, suggesting their potential for clinical cancer treatment.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2022)
Article
Cardiac & Cardiovascular Systems
Cynthia Aparecida Castro, Tereza Cristina Buzinari, Rafael Luis Bressani Lino, Heloisa Sobreiro Selistre de Araujo, Fernanda de Freitas Anibal, Roberto Mario Machado Verzola, Vanderlei Salvador Bagnato, Natalia Mayumi Inada, Gerson Jhonatan Rodrigues
Summary: The study evaluated the role of TNF-α and IL-6 in foam cell formation, confirming that higher concentrations of FITC-ox-LDL led to more accumulation of lipoproteins in cells and higher production of TNF-α and IL-6.
ARQUIVOS BRASILEIROS DE CARDIOLOGIA
(2022)
Article
Materials Science, Paper & Wood
Deyvid S. Porto, Ana Cassales, Heloisa Ciol, Natalia M. Inada, Elisabete Frollini
Summary: This study demonstrates the use of microcrystalline cellulose as a polyol in the synthesis of polyurethane films. The films exhibit transparency, high crystallinity, and moderate hydrophobicity. Biocompatibility tests show non-cytotoxicity, indicating potential applications in coatings, packaging, and dressings.
Article
Robotics
Mateus Gasparino, Arun N. Sivakumar, Yixiao Liu, Andres E. B. Velasquez, Vitor A. H. Higuti, John Rogers, Huy Tran, Girish Chowdhary
Summary: We propose a self-supervised learning approach for wheeled mobile robots to predict traversable paths. Our method autonomously generates paths using RGB and depth data, along with navigation experience, and trains a neural network using online traction estimates, avoiding the need for heuristics used by previous methods.
IEEE ROBOTICS AND AUTOMATION LETTERS
(2022)
Article
Biochemistry & Molecular Biology
Regina Westphal, Eclair Venturini Filho, Laiza Bruzadelle Loureiro, Claudio Francisco Tormena, Claudia Pessoa, Celina de Jesus Guimaraes, Mariana Palmeira Manso, Rodolfo Goetze Fiorot, Vinicius Rangel Campos, Jackson Antonio Lamounier Camargos Resende, Fabrizio Medici, Sandro Jose Greco
Summary: In this study, a microwave-assisted Knoevenagel/Michael/cyclization multicomponent domino methodology was developed for the synthesis of spiro compounds. Twelve spiro compounds were synthesized and one of them exhibited anti-cancer activity.
Article
Oncology
Felipe Pereira, Sarah Raquel de Annunzio, Thais de Assis Lopes, Kleber Thiago de Oliveira, Eduardo Maffud Cilli, Paula Aboud Barbugli, Carla Raquel Fontana
Summary: The study evaluated the antimicrobial effects of AMP P5 and aPDT mediated by bixin and chlorin-e6 on Cutibacterium acnes, with Ce6 proving to be a more efficient photosensitizer. The combination of P5 with Ce6-aPDT showed a synergistic effect in reducing microbial load on bacterial biofilm.
PHOTODIAGNOSIS AND PHOTODYNAMIC THERAPY
(2022)
Article
Chemistry, Multidisciplinary
Coral Mycroft, Guilherme Dal Poggetto, Thaiis M. Barbosa, Claiudio F. Tormena, Mathias Nilsson, Gareth A. Morris, Laura Castanar
Summary: The NMR analysis of fluorine-containing molecules is important in pharmaceuticals and biochemistry, but faces challenges due to severe peak overlap. This study introduces a new method, IPAP-FESTA, that simplifies measurements of proton-fluorine couplings. Its usefulness is demonstrated in the structural study of the drug fluticasone propionate and in assessing solvent effects on fluorohydrin conformational equilibrium in a mixture.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Materials Science, Multidisciplinary
Luiz Gustavo Bonato, Guilherme Dal Poggetto, Raphael Fernando Moral, Brener Rodrigo de Carvalho Vale, Jose Carlos Germino, Diogo Burigo Almeida, Patricia Santiago, Pablo Sebastian Fernandez, Claudio Francisco Tormena, Lazaro A. Padilha, Ana Flavia Nogueira
Summary: In this study, the influence of organic ligands on the photostability of CsPbBr3 perovskite nanocrystals was investigated. The results demonstrate that alkylphosphate ligands can improve the photostability of colloidal nanocrystals dispersions, which is important for applications requiring continuous excitation.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Biochemistry & Molecular Biology
Marciana Pierina Uliana, Andreia da Cruz Rodrigues, Bruno Andrade Ono, Sebastiao Pratavieira, Kleber Thiago de Oliveira, Cristina Kurachi
Summary: This study describes the semi-synthesis of cost-effective photosensitizers derived from chlorophyll a and their effectiveness in photodynamic inactivation against different microorganisms. The results indicate that these nature-inspired PSs are highly effective and promising alternatives for selectively inactivating microorganisms.
Article
Optics
N. Piovella, G. R. M. Robb, R. Bachelard
Summary: This study demonstrates the coherent transfer of orbital angular momentum (OAM) from a laser beam to a Bose-Einstein condensate in a ring trap, in quantized units of h??. The control of specific angular momentum states allows for the generation of light with different OAM than the pump light through the imprinting of the atomic ring on the scattered light.
Proceedings Paper
Dermatology
Priyanka Vasanthakumari, Renan A. Romano, Ramon G. T. Rosa, Ana G. Salvio, Vladislav Yakovlev, Cristina Kurachi, Javier A. Jo
Summary: The study utilizes a deep learning model and multispectral autofluorescence lifetime dermoscopy images for the diagnosis of melanoma, and evaluates the diagnostic performance by constructing probability maps and using Receiver Operator Characteristics (ROC). The results demonstrate that the method can effectively distinguish between benign and malignant lesions.
PHOTONICS IN DERMATOLOGY AND PLASTIC SURGERY 2022
(2022)
Article
Chemistry, Organic
Fuying Zhu, Yamei Lin
Summary: In this study, a low-metal iron-supported catalyst (Fe20/NC-Mg) was reported for the efficient synthesis of quinoxaline compounds, using water as a solvent and without additional bases. The synergistic effect of FeNx site and Mg (OH)2 nanorods in the catalyst played a key role in achieving high yields (82-91%) in 16 examples. The gram-level synthesis and reusability of the catalysts after four cycles demonstrated its industrial application potential.
Article
Chemistry, Organic
Mikhail Kozlov, Alexey Tyurin, Andrey Dmitrenok, Vyacheslav Rusak, Aleksander Fedorov, Igor Zavarzin, Yulia Volkova
Summary: This study presents a novel and practical synthesis method for phosphorus-substituted 1,3,4-thiadiazolines using phosphorylthioformic acid hydrazides and ketones. The protocol demonstrates operational simplicity, availability of reagents, and tolerance towards different functional groups.
Article
Chemistry, Organic
Jisna Jose, Thomas Mathew
Summary: 2-Cyclopentenone and its derivatives are highly esteemed synthetic intermediates with exceptional utility in organic synthesis. They are favored structural motifs in numerous pharmaceutical drugs and natural products, highlighting their significance. The review discusses the various methods used to synthesize cyclopentenones from 2016 to 2023.
