Article
Chemistry, Organic
Iliyasu Aliyu Bashir, Sunwoo Lee
Summary: Symmetrical anhydrides can be synthesized from activated amides such as N-benzoylsaccharins and N-Boc-protected benzamides. The reaction of activated amides with H2O in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) at 25 degrees C can efficiently cleave the C-N bond and yield the corresponding symmetrical anhydrides in high yields. Additionally, N-benzoylsaccharins can react with benzoic acid derivatives to generate unsymmetrical anhydrides in high yields.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Pinku Tung, Neal P. Mankad
Summary: A light-mediated, Cu-catalyzed process has been developed for directly producing aliphatic, symmetric acid anhydrides from alkyl (pseudo)halides in a single step without the need for precious metal additives. This transformation utilizes simple Cu salts and abundant bases to generate a heterogeneous Cu0 photocatalyst in situ, maintaining high efficiency and selectivity upon scale-up, and operates via a radical mechanism with several advantageous features. This discovery will facilitate the engineering of efficient and sustainable bulk processes for producing commodity anhydrides.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Applied
Guofu Zhang, Qiankun Fan, Huimin Wang, Yiyong Zhao, Chengrong Ding
Summary: A new protocol for the synthesis of sulfinic esters via esterification of sulfonyl hydrazides with alcohols using NaHSO3 as the promoter has been developed. This method offers mild transition-metal-free reaction conditions, an inexpensive and readily available reagent, and operational simplicity. Controlled experiments suggest that the transformation likely proceeds through a radical pathway.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Shihao Li, Haojun Shu, Sheng Wang, Wenqing Yang, Fei Tang, Xiao-Xuan Li, Shilu Fan, Yi-Si Feng
Summary: An intermolecular 1,2-diacylation of alkenes is achieved through cooperative N-heterocyclic carbene and photoredox catalysis mediated by PPh3 and Cs2CO3. This method provides a practical approach for the synthesis of 1,4-dicarbonyl compounds and pharmaceutical derivatives. Regioselective dicarbonyl compounds can be synthesized by utilizing acyl azolium salt. Mechanistic investigations reveal a critical radical/radical cross coupling of ketyl radicals with benzylic C-radicals.
Article
Chemistry, Multidisciplinary
Enrique Reyes-Bravo, Dino Gnecco, Jorge R. Juarez, Maria L. Orea, Sylvain Bernes, David M. Aparicio, Joel L. Teran
Summary: This study describes the synthesis of new chiral highly functionalized zwitterionic bicyclic lactams starting from acyclic beta-enaminoesters derived from (R)-(-)-2-phenylglycinol. The key step involves an intramolecular non-classical Corey-Chaykovsky ring-closing reaction of the corresponding sulfonium salts derived from beta-enaminoesters. This methodology allows for the generation of two or three new stereogenic centers with high diastereoselectivity, and the utility of these intermediates was demonstrated by the stereocontrolled total synthesis of cis-4-hydroxy-2-methyl piperidine and its corresponding pipecolic acid derivative.
Article
Chemistry, Organic
Joydev K. K. Laha, Anjali Gupta, Upma Gulati, Mandeep Kaur Hunjan, J. Patrick Weber, Martin Breugst
Summary: This study explores the application of isoniazid and other pyridine acyl radicals in organic synthesis. The radicals are generated through denitrogenation reactions and react with amines to yield pyridine carboxamides in moderate to high yields. The method offers mild and metal-free reaction conditions, water as a solvent, a wide substrate scope, and excellent functional-group tolerance.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Inorganic & Nuclear
M. Sharath Babu, A. Srivani, B. Srinivasa Rao, Dasari Ayodhya
Summary: In this study, indium-modified heteropoly tungstate catalysts were synthesized to enhance the Lewis acidity. The catalysts were characterized by various techniques, confirming the presence of Keggin ion structure after modification. The modification with indium ions improved the acidity and stability of the catalysts. Pyridine adsorbed FT-IR spectra indicated the presence of Lewis acidic sites associated with indium ions. The catalysts showed different acidity and activity depending on the amount of indium ions. The partially exchanged In0.66TPA catalyst exhibited high glycerol conversion and selectivity to glycerol carbonate. Optimum reaction conditions were determined by investigating various reaction parameters.
INORGANICA CHIMICA ACTA
(2023)
Article
Chemistry, Organic
Xuewei Wang, Yongli Zhao, Jinhua Yang, Yanxi Li, Ying Luo, Mengyao Xu, Junfeng Zhao
Summary: A novel strategy for thioester synthesis using ynamide was developed, showing no detectable racemization for thioesterifications of carboxylic acids with alpha-chiral centers. The method is compatible with amino acid side chain functional groups and can also be used for selenoesters.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Xiaofang Wu, Lei Zhou, Fangshao Li, Jing Xiao
Summary: A novel method utilizing PCl3 has been developed for the conversion of tert-butyl esters into esters and amides in one-pot under air. This method enables the synthesis of bioactive molecule skeletons and gram-scale reactions, and involves the formation of an acid chloride followed by reactions with alcohols or amines to produce the desired products.
JOURNAL OF CHEMICAL RESEARCH
(2021)
Article
Chemistry, Organic
Fangshao Li, Xiaofang Wu, Fengzhe Guo, Zi-Long Tang, Jing Xiao
Summary: A general and efficient method for the iodine-promoted chlorination of amides and esters with phosphorus trichloride is described, allowing for the direct conversion of various inactivated amides to the corresponding acid chlorides, as well as exploring the substrate scope of methyl esters. This simple, scalable and wide-ranging approach provides a method for the preparation of these acid chlorides.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Madhukar S. Said, Nilesh S. Khonde, Pradeep Kumar, Jayant M. Gajbhiye
Summary: This study reveals a method for the synthesis of trifluoromethyl ketones via the fluoroarene-mediated trifluoromethylation of carboxylic acids. The fluoroarene activates the acid group and generates the fluoride source in situ for the trifluoromethylation reaction. The protocol is safe, metal-free, operates under mild conditions, and does not require external additives to generate trifluoromethyl anion. The transformation shows good functional group tolerance and delivers high yields of trifluoromethyl ketones in both batch and continuous flow processes.
Article
Biochemistry & Molecular Biology
Maria Carolina Pereira Goncalves, Jessica Cristina Amaral, Roberto Fernandez-Lafuente, Ruy de Sousa Junior, Paulo Waldir Tardioli
Summary: This paper investigated the Lipozyme 435-catalyzed synthesis of xylose oleate in MEK, studying the effects of substrate ratios, temperature, and time on esterification rates. Results showed that an excess of oleic acid was favorable for the reaction, and the highest Lipozyme 435 activities occurred between 55 and 70 degrees C. The study also found that the predicted kinetic model fitted well with experimental data and there was no evidence of inhibitions.
Article
Chemistry, Multidisciplinary
Yundong Wu, Lei Guo, Yuxuan Liu, Jiannan Xiang, Jun Jiang
Summary: A selective and mild method for the synthesis of N-aryl amides was developed in this study, with good yields obtained in water from commercially available nitroarenes and acyl halides. The reaction, with Fe dust as the only reductant and additive, can be easily performed on a large scale.
Article
Chemistry, Multidisciplinary
Sailam Sri Gogula, Kamalaker Reddy Kamireddy, Saraswathi Meesa, Sunil Misra, Ch. Abraham Lincoln, P. Muralidhar Reddy
Summary: A novel synthesis of chromenopyridine derivatives using formyl chromone and beta-enaminoester mediated by indium (III) has been developed, which exhibit various biological activities. The synthesized compounds were characterized and tested for antifungal activity against Candida test pathogens. Out of 16 compounds, 12 showed antifungal activity, with four (3c, 3f, 3g, and 3n) exhibiting good inhibition against all pathogens. Microbial least inhibition concentration and minimum fungicidal concentration determination revealed values between 7.8 and 250 μg/mL towards the selected fungal pathogens.
Article
Biochemistry & Molecular Biology
Cecilia Garcia-Oliva, Almudena Perona, Angel Rumbero, Pilar Hoyos, Maria J. Hernaiz
Summary: This study reports the enzymatic synthesis of rhamnose fatty acid esters through transesterification using lipase from Pseudomonas stutzeri as a biocatalyst. Optimum conditions were determined for achieving high conversion and regioselectivity, and the role of various reaction conditions was investigated. The use of specific solvents and acyl donors with different chain lengths greatly influenced the efficiency of the reaction. The enzyme's regioselectivity and its ability to accommodate ester chains of different lengths were explained through molecular modeling and simulation studies.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Inorganic & Nuclear
Felipe Dornelles da Silva, Artur Luis Hennemann, Robert Alan Burrow, Ernesto Schulz Lang, Ulrich Abram, Sailer Santos dos Santos
Summary: This study investigated the synthesis and structural characterization of six new [HgTe]-based cluster compounds derived from bis(2-pyridyl)ditellane and different mercury salts. Various techniques, including single-crystal X-ray diffraction and FT-IR spectroscopy, were used to study the compounds, and their optical properties were evaluated by solid-state UV-Vis diffuse reflectance spectroscopy. The results showed a strong dependence of the optical properties on the core structure's size and composition, with smaller core structures presenting larger energy gap values.
JOURNAL OF CLUSTER SCIENCE
(2022)
Article
Chemistry, Organic
Wanderson C. Souza, Jose Tiago M. Correia, Priscilla M. Matos, Camila M. Kisukuri, Pablo S. Carneiro, Marcio W. Paixao
Summary: This study presents a new approach for the synthesis of 1,3-diene derived quinolinone compounds using a mild reaction protocol, a metal-free catalyst, and a sustainable solvent. The methodology offers an efficient route towards decorated 1,3-diene products.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Review
Biochemistry & Molecular Biology
Flavio A. R. Barbosa, Romulo F. S. Canto, Kerolain F. Teixeira, Anacleto S. de Souza, Aldo S. de Oliveira, Antonio L. Braga
Summary: Alzheimer's disease (AD) is a prevalent type of dementia that affects millions of older people worldwide. Selenium-containing compounds have shown potential as multi-targeted drugs for the treatment of AD due to their antioxidant and anticholinesterase properties. These compounds can decrease the aggregation of amyloid-beta (A beta), a key feature of AD. Some selenium-derived compounds have molecular features similar to FDA-approved drugs, suggesting that they may have optimized pharmacokinetic properties.
CURRENT MEDICINAL CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Lenna Rosanie Cordero Mallaupoma, Barbara Karina de Menezes Dias, Maneesh Kumar Singh, Rute Isabel Honorio, Myna Nakabashi, Camila de Menezes Kisukuri, Marcio Weber Paixao, Celia R. S. Garcia
Summary: Melatonin can synchronize the intraerythrocytic cycle of the parasite by triggering a specific signaling cascade. Compounds with certain chemical structures have inhibitory effects on the proliferation of malaria parasites, indicating their potential as new antimalarial drugs. The study found that certain synthetic compounds can inhibit different chloroquine-resistant strains of the parasite. In addition, melatonin affects the parasite load and modulates the expression of signaling components, providing a focus for further research.
Review
Chemistry, Organic
Guilherme A. M. Jardim, Juliana A. Dantas, Amanda A. Barboza, Marcio W. Paixao, Marco A. B. Ferreira
Summary: Visible-light-induced palladium-mediated reactions have shown great potential in organic synthesis and can achieve new and unique reactivities by generating versatile Pd-radical hybrid species. This review provides an overview of recent advances in the combination of Pd-based photocatalytic manifolds and radical generation in the functionalization of important motifs in synthetic chemistry.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Organic
Wanderson C. C. de Souza, Rafaely N. N. Lima, Iva S. S. de Jesus, Jose Tiago M. Correia, Marcio W. Paixao
Summary: A deaminative alkyl radical cascade cyclization of 1,7-dienes under visible-light photocatalysis is reported. This method enables the synthesis of a family of benzoazepinones (benzazepinones) and can be carried out under mild reaction conditions, providing a broad substrate scope with excellent functional group tolerance and good yields. This protocol has also been extended to 1,7-enynes, resulting in a representative collection of cyclopentaquinolinones.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Multidisciplinary
Kimberly Benedetti Vega, Jose Antonio Campos Delgado, Lucas V. B. L. Pugnal, Burkhard Koenig, Jose Tiago Menezes Correia, Marcio Weber Paixao
Summary: In this study, a strategy for the precise installation of sulfones and carboxylic acids onto styrenes using sodium sulfinates and CO2 as coupling partners was described. The protocol allowed for the preparation of carboxy-sulfonylated compounds with high yields and broad functional group tolerance. Additionally, a one-pot photocatalytic carboxy-sulfonylation-elimination strategy was developed for the synthesis of alpha-aryl-acrylates by taking advantage of the leaving group ability of the sulfone moiety.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Fabricia Nunes da Silva, Hugo Marchi Luciano, Carlos H. Stadtlober, Giliandro Farias, Fabien Durola, Juliana Eccher, Ivan H. Bechtold, Harald Bock, Hugo Gallardo, Andre A. Vieira
Summary: This study found that triply phenanthryl- and tetrahelicenyl-substituted triazine-hexaalkyl esters with short alkyl chains can exhibit glass transitions conveniently above room temperature within the hexagonal columnar liquid crystalline state, resulting in a solid columnar order at room temperature. These glassy columnar liquid matrices can be used for the orientation of guest emitters to achieve anisotropic emission, as the hexagonal columnar mesophase can be easily aligned with a perpendicular director on a solid substrate. The condition for face-on alignment on substrates can be achieved with the moderately nonplanar tetrahelicenyl derivatives, despite their short alkyl periphery. An unusual phase transition between two columnar mesophases of the same hexagonal symmetry but very different long-distance regularity of the column lattice was found in one phenanthryl homolog.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Hugo Marchi Luciano, Giliandro Farias, Cristian M. Salla, Larissa G. Franca, Suman Kuila, Andrew P. Monkman, Fabien Durola, Ivan H. Bechtold, Harald Bock, Hugo Gallardo
Summary: By incorporating sulfur-containing thiophene bridges, the spin-orbit coupling associated with the radiative T-1 -> S-0 pathway was enhanced, allowing room-temperature phosphorescence to be observed in solution for all compounds.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Fabricia Nunes da Silva, Hugo Marchi Luciano, Carlos H. Stadtlober, Giliandro Farias, Fabien Durola, Juliana Eccher, Ivan H. Bechtold, Harald Bock, Hugo Gallardo, Andre A. Vieira
Summary: Columnar liquid crystals with small molecular masses are obtained by mixed dissymmetric substitution of sym-triazine, showing stable mesophase and pronounced calorimetric glass transitions. The small molecules do not require long ester tails to induce liquid crystalline state, leading to the absence of insulating and weight-increasing alkyl periphery. The films obtained from solution exhibit resistance to crystallization during annealing, indicating the direct formation of columnar hexagonal mesoscopic order.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Spectroscopy
Tiago E. A. Frizon, Cristian A. M. Salla, Felipe Grillo, Fabiano S. Rodembusch, Viktor S. Camara, Henrique C. Silva, Eduardo Zapp, Eduardo Junca, Fabio Z. Galetto, Angelica M. de Costa, Gabriela J. Pedroso, Antonio A. Chepluki, Sumbal Saba, Jamal Rafique
Summary: This study synthesized new PMDI derivatives through proton-transfer reactions in the excited state (ESIPT). These compounds exhibited absorption maxima in the ultraviolet region and showed redshifted absorptions compared to the non-ESIPT dye. They also displayed fluorescence emissions dependent on solvent polarity and chemical structure, with ESIPT derivatives showing dual fluorescence and a large Stokes shift. The compounds demonstrated good thermal stability and electrochemical properties.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Biochemistry & Molecular Biology
Mauricio Tavares Jacques, Viviane de Souza, Flavio Augusto Rocha Barbosa, Romulo Faria Santos Canto, Samantha Cristiane Lopes, Rui Daniel Prediger, Antonio Luiz Braga, Michael Aschner, Marcelo Farina
Summary: Oxidative glutamate toxicity is a harmful mechanism in ischemic stroke. Two new probucol analogues (C1 and C2) were designed and synthesized, and their effects against glutamate-induced neuronal oxidative toxicity were investigated. C2 showed the lowest toxicity and provided significant protection against glutamate-induced cytotoxicity both in vitro and in vivo. This study presents a promising neuroprotective drug for ischemic stroke.
ACS CHEMICAL NEUROSCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Priscila Pazini Abatti, Nicolas Oliveira Decarli, Szymon Gogoc, Przemyslaw Data, Ivan H. Bechtold, Eduard Westphal, Hugo Gallardo
Summary: Three tetraaryl-1,4-dihydropyrrolo[3,2-b]pyrrole derivatives with different numbers of long alkoxy chains were synthesized and applied in OLEDs. These compounds showed good emission properties and exhibited different emission features in solution and solid state. Additionally, the compounds formed aggregates with redshifted emission.
Article
Chemistry, Multidisciplinary
Muhammad Saeed Ahmad, Abu Bakar Siddique, Muhammad Khalid, Akbar Ali, Muhammad Ashraf Shaheen, Muhammad Nawaz Tahir, Muhammad Imran, Ahmad Irfan, Muhammad Usman Khan, Marcio Weber Paixao
Summary: In this study, a one-pot synthesis of tetra-substituted imidazole was reported, and a series of metal complexes were obtained by reacting the synthesized imidazole with salts of 1(st) row transition metals. The synthesized compounds were characterized using spectroscopic and analytical techniques, and their antioxidant and antimicrobial activities were evaluated. The results showed that the metal complexes exhibited stronger antimicrobial activity compared to the ligand, and the ligand had better antioxidant activity than the metal complexes. Computational studies revealed a clear intra-molecular charge transfer in the ligand and its metal complexes.
Article
Chemistry, Multidisciplinary
Carlos V. Doerner, Jose S. S. Neto, Climei R. Cabreira, Sumbal Saba, Louis P. Sandjo, Jamal Rafique, Antonio L. Braga, Francisco F. de Assis
Summary: Here, an original and sustainable synthetic methodology for the synthesis of 3-selanyl-isoflavones from 2-hydroxyphenyl enaminones and diorganoyl diselenides is presented. The reaction, promoted by trichloroisocyanuric acid and using ethanol as a solvent, proceeds in a one-pot manner under mild conditions. Using this protocol, 22 examples of 3-selanyl-isoflavones were prepared in yields ranging from 34% to 95%.
NEW JOURNAL OF CHEMISTRY
(2023)
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.
