Article
Chemistry, Applied
Yanyan Wang, Zhen Cao, Nengzhong Wang, Mingguo Liu, Haifeng Zhou, Long Wang, Nianyu Huang, Hui Yao
Summary: A versatile S-glycosylation approach was developed using palladium-catalyzed allylic substitution to form alpha- and beta-thioglycosides under mild conditions. The method exhibited high functional group tolerance and stereoselectivity, yielding 70%-86% of thioglycosides. This protocol also enabled quick synthesis of various S-linked disaccharides and glycopeptides.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Nuria Vazquez-Galinanes, Isabel Velo-Heleno, Martin Fananas-Mastral
Summary: A method for the use of vinyl epoxides in catalytic allylboration of alkynes is described, which allows for the synthesis of bifunctional skipped dienes bearing both an allylic alcohol and an alkenylboronate from simple starting materials with high regio- and stereoselectivity. These products show versatile reactivity and can be converted into cyclic boron compounds and polyenes.
Article
Chemistry, Physical
Diego Olivieri, Riccardo Tarroni, Nicola Della Ca', Raffaella Mancuso, Bartolo Gabriele, Gilberto Spadoni, Carla Carfagna
Summary: We have developed a chemoselective method for the carbonylation of allylic substrates, leading to alkyl succinates with preservation of the X group. Our method exhibits a completely different selectivity compared to the classical substitutive carbonylation of allyl compounds. By optimizing the ligand and nucleophile, as well as through DFT calculations, we achieved moderate to good yields of succinate derivatives.
Article
Chemistry, Organic
Eric M. Miller, Maciej A. Walczak
Summary: This study presents stereoselective C-arylation and etherification reactions of anomeric trifluoroborates derived from BMIDA esters, exhibiting high anomeric selectivities for 2-deoxysugars and showing a broad substrate scope, including disaccharides and trifluoroborates with free hydroxyl groups. This new class of carbohydrate reagents adds to the palette of anomeric nucleophile reagents suitable for efficient installation of C-C bonds.
Article
Chemistry, Physical
Marion Duval, Victor Deboos, Agnes Hallonet, Gilles Sagorin, Audrey Denicourt-Nowicki, Alain Roucoux
Summary: Palladium nanoparticles with core sizes of approximately 2.5 nm were synthesized by chemical reduction and found to be efficient for the selective hydrogenolysis of various aromatic and aliphatic epoxides in water. The study also identified the most suitable capping agents and reaction conditions for different industrial substrates, leading to the successful hydrogenation of 7,8-epoxy-2-methoxy-2,6-dimethyloctane into Florsantol (R) at a multigram scale.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Applied
Kameshwar Prasad, Ananay Sharma, Soumyaranjan Pati, Marc Taillefer, Florian Jaroschik, Srinivas Hotha
Summary: We report metal free conditions for the activation of alkynyl glycosyl carbonate donors using I-2/TMSOTf in stoichiometric quantities. The extrusion product was characterized as vinylidene iodide by single crystal X-ray analysis. The reaction conditions were suitable for the synthesis of various glycosides, purine/pyrimidine nucleosides, and a pentasaccharide repeating unit of Klebsiella pneumoniae (O-3 antigen).
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Review
Biotechnology & Applied Microbiology
Jie Ren, Caleb Don Barton, Jixun Zhan
Summary: Polyphenolic compounds can be biosynthesized into glycosides with improved hydrophilicity through glycosylation, which decreases toxicity, increases bioavailability and stability, and changes bioactivity. Engineered biosynthesis provides an environmentally friendly and cost-effective approach to generate polyphenolic glycosides using glycosyltransferases and sugar biosynthetic enzymes.
BIOTECHNOLOGY ADVANCES
(2023)
Article
Chemistry, Multidisciplinary
Carla Obradors, Benjamin Mitschke, Miles H. Aukland, Markus Leutzsch, Oleg Grossmann, Sebastian Brunen, Sebastian A. Schwengers, Benjamin List
Summary: Since early 2020, scientists have been striving to find effective solutions to combat SARS-CoV-2, focusing on developing reliable vaccines and repurposing drugs. However, the current synthetic routes for Remdesivir, the most widely used therapeutic during the early stages of infection, face challenges in cost-effective supply to patients. In this study, researchers have developed a straightforward method for adding (hetero)arenes to unprotected sugars, significantly expediting the synthesis of Remdesivir precursor GS-441524.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Sijing Xue, Bart Limburg, Debasish Ghorai, Jordi Benet-Buchholz, Arjan W. Kleij
Summary: Dual palladium/photoredox-catalysis is an effective method for the decarboxylative asymmetric synthesis of vicinal alpha,beta-tri/tetra- or alpha,beta-tetrasubstituted homoallylic alcohols using Hantzsch-type esters as radical precursors. This methodology utilizes vinyl cyclic carbonates as accessible reagents to provide the target molecules in appreciable to good yields, high branch selectivity, and enantiomeric ratios of up to 94:6, making it a rare example of using prochiral electrophiles for the creation of vicinal congested carbon centers.
Article
Plant Sciences
Qinggang Yin, Yiding Wei, Xiaoyan Han, Jingwang Chen, Han Gao, Wei Sun
Summary: Chinese horse chestnut flowers and leaves contain abundant flavonoids, with significantly higher content of seven flavonol glycosides in flowers than in leaves. The crude proteins of flowers can catalyze the formation of flavonol glucosides. These studies provide theoretical and experimental basis for the utilization of Chinese horse chestnut flowers and leaves as additives and dietary supplements.
FRONTIERS IN PLANT SCIENCE
(2022)
Article
Chemistry, Physical
Prashant Kumar, Pravesh Kumar, Sugumar Venkataramani, S. S. V. Ramasastry
Summary: This study reveals a new chemical reactivity pattern of allylic gem-diacetates and successfully synthesizes complex benzo[f]chromene compounds, demonstrating the versatility of the method. Additionally, interesting photochromic properties of the new classes of benzo[f]chromenes are discovered.
Article
Chemistry, Physical
Prashant Kumar, Pravesh Kumar, Sugumar Venkataramani, S. S. V. Ramasastry
Summary: This work explores the unusual chemical reactivity pattern of allylic gem-diacetates and establishes them as new prototypes for synthesizing complex benzo[f]chromene systems. The versatility of the method in synthesizing bioactive natural products based on chromene is demonstrated, along with the discovery of interesting photochromic properties of the new classes of benzo[f]chromenes.
Article
Chemistry, Physical
Caitlin Kozack, Stephen J. Tereniak, Jonathan N. Jaworski, Bao Li, David L. Bruns, Spring M. M. Knapp, Clark R. Landis, Shannon S. Stahl
Summary: This study focuses on the impact of benzoquinone on the catalytic activity in palladium(II)-catalyzed allylic acetoxylation. The results indicate that benzoquinone enhances the performance of the catalyst, showing a synergistic effect with Co(salophen) in improving reaction performance. The mechanistic studies suggest that both benzoquinone and oxygen play significant roles in oxidizing Pd(0) to Pd(II), leading to better reaction outcomes.
Article
Chemistry, Multidisciplinary
Wei-Cheng Zhao, Rui-Peng Li, Chao Ma, Qi-Ying Liao, Miao Wang, Zhi-Tao He
Summary: A novel protocol for stereoselective geminal bisglycosylations of saccharides has been established, showcasing the simultaneous introduction of C-C and C-B bonds at the anomeric stereogenic center of furanoses and pyranoses. Additionally, a scarce metal-free 1,1-difunctionalization process of alkenes has been demonstrated.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Review
Chemistry, Multidisciplinary
Bruna Martins Guimaraes, Rayane de Oliveira Silva, Maria Veronica de Sales Barbosa, Jucleiton Jose Rufino de Freitas, Juliano Carlo Rufino Freitas, Ronaldo Nascimento de Oliveira, Joao Rufino de Freitas Filho
Summary: This review covers the recent advances in the natural occurrence, synthesis, mechanism, and pharmacological applications of N-glycopyranosides from 2010 to 2022.
Article
Chemistry, Organic
Yogesh Jaiswal, Yogesh Kumar, Rima Thakur, Jagannath Pal, Ranga Subramanian, Amit Kumar
JOURNAL OF ORGANIC CHEMISTRY
(2016)
Article
Chemistry, Organic
Yogesh Kumar, Mukta Shaw, Rima Thakur, Amit Kumar
JOURNAL OF ORGANIC CHEMISTRY
(2016)
Article
Chemistry, Organic
Rima Thakur, Girish K. Rawal, Yashwant D. Vankar
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2017)
Article
Chemistry, Multidisciplinary
Yogesh Kumar, Yogesh Jaiswal, Rima Thakur, Amit Kumar
Article
Chemistry, Organic
Rima Lahiri, Ashokkumar Palanivel, Sudhir A. Kulkarni, Yashwant D. Vankar
JOURNAL OF ORGANIC CHEMISTRY
(2014)
Article
Chemistry, Organic
Mukta Shaw, Rima Thakur, Amit Kumar
JOURNAL OF ORGANIC CHEMISTRY
(2019)
Article
Chemistry, Organic
Mosidur Rahaman Molla, Pradip Das, Kanika Guleria, Ranga Subramanian, Amit Kumar, Rima Thakur
JOURNAL OF ORGANIC CHEMISTRY
(2020)
Article
Chemistry, Organic
Rima Thakur, Yogesh Jaiswal, Amit Kumar
Summary: Primary amides serve as crucial coordinating directing groups for transition-metal catalyzed C-H activation reactions, enabling site-selective activation of ortho-C-H bonds in aromatic compounds, leading to diverse molecular architectures.
Article
Chemistry, Multidisciplinary
Pradip Das, Mosidur Rahaman Molla, Amit Kumar, Rima Thakur
Summary: The study reports an efficient and stereoselective synthesis of 2,3-dideoxy-beta-O-glycosides from C3-(o-cyanobenzoate) ester protected glycal donors via Ferrier rearrangement under Pd(0)-catalyzed Tsuji-Trost conditions. The stereo-chemical outcome of the reactions was independent of the nature of protecting groups or conformational flexibility of the glycal donors. Incorporation of the directing group on the benzoate ester altered the reactivity for Tsuji-Trost as well as Ferrier Rearrangement pathway.
CHEMISTRY-AN ASIAN JOURNAL
(2022)
Article
Chemistry, Organic
Mosidur Rahaman Molla, Rima Thakur
Summary: The use of (1 N/2 N)-methylated tetrazole methyl ethers as a C2-directing group for the formation of 1,2-trans-beta-O-glycosides, in combination with the activation of tethered thioglycoside donors by PIFA-TfOH reagent system, allows for efficient glycosylation reactions with high selectivity.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Pradip Das, Rima Thakur
Summary: The Ferrier rearrangement on glycals is a highly efficient method for synthesizing 2,3-dideoxyglycosides, enabling the access to various sugar derivatives through olefin functionalization. The classical acid-mediated transformation selectively delivers the α-O-glycosides. In this approach, amides derived from amino acids glycine and proline are utilized as sustainable β-directing leaving groups on glycal substrates. These directing groups facilitate the β-selective Ferrier rearrangement for hard alcohol nucleophiles via the Pd(0)-catalyzed Tsuji-Trost inner sphere pathway.
Article
Chemistry, Organic
Mosidur Rahaman Molla, Rima Thakur
Summary: A new readily synthesized orthogonal protecting group, cyanomethyl (CNMe) ether, has been reported for efficient protection of saccharides with easy removal.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Review
Chemistry, Organic
Rima Thakur, Yogesh Jaiswal, Amit Kumar
ORGANIC & BIOMOLECULAR CHEMISTRY
(2019)
Article
Chemistry, Organic
Mukta Shaw, Amit Kumar, Rima Thakur
TRENDS IN CARBOHYDRATE RESEARCH
(2017)
Article
Chemistry, Organic
Mukta Shaw, Yogesh Kumar, Rima Thakur, Amit Kumar
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
(2017)
