Article
Chemistry, Multidisciplinary
Sooyeon Moon, Sourav Chatterjee, Peter H. Seeberger, Kerry Gilmore
Summary: By quantifying the steric and electronic contributions of all chemical reagents and solvents through quantum mechanical calculations, a random forest algorithm was trained to accurately predict the stereoselective outcome of glycosylations. The model accurately predicts stereoselectivities for unseen nucleophiles, electrophiles, acid catalyst, and solvents across a wide temperature range, and was experimentally validated on a microreactor platform. This model helps identify novel ways to control glycosylation stereoselectivity and accurately predicts previously unknown means of stereocontrol.
Article
Chemistry, Organic
Maude Cloutier, Serge Lavoie, Charles Gauthier
Summary: This study thoroughly investigated the reaction conditions and structural parameters of benzylidene acetal-protected 3-O-acyl-fi-D-idopyranosides through extensive glycosylation study, NMR analyses, X-ray diffraction, and quantum molecular modeling. It not only reported a direct and fi-stereoselective idosylation approach, but also provided fundamental structural insights into the conformational flexibility of idose.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Maude Cloutier, Serge Lavoie, Charles Gauthier
Summary: Through glycosylation study and multiple analysis methods, we have thoroughly investigated the Lewis acid-catalyzed C7 epimerization of benzylidene acetal-protected 3-O-acyl-fi-D-idopyranosides. Our work not only presents a direct, fi-stereoselective idosylation approach, but also provides fundamental structural insights into the conformational flexibility of idose.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Michael P. Maloney, Brock A. Stenfors, Paul Helquist, Per-Ola Norrby, Olaf Wiest
Summary: This Perspective provides an overview of the current methods used in the application of computational methods in enantioselective catalysis, with particular emphasis placed on the Q2MM/CatVS method. Through case studies, it is argued that computational methods have become equal partners to experimental studies and can correct published results in some cases. Finally, the consequences of this approach to data-driven methods are discussed.
Article
Chemistry, Organic
Taeok Kim, Michael R. Bell, V. Narasimharao Thota, Todd L. Lowary
Summary: This study reports a one-pot strategy for functionalizing pyranoside 1,2-cis-diols with two different ester protecting groups. The approach selectively acylates through orthoester hydrolysis promoted by a carboxylic acid, and after removal of water and introduction of a coupling agent, the carboxylic acid is esterified with the liberated hydroxyl group. Although applied to 1,2-cis-diols on pyranoside scaffolds, this method can be applicable to similar motifs on any six-membered ring.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Catherine Alex, Alexei V. Demchenko
Summary: This paper describes a new method for the direct, highly stereoselective synthesis of glycans containing beta-linked D-mannosaminuronic acid (ManNAcA) residues, including the capsular polysaccharide of Staphylococcus aureus type 8. The method achieves stereocontrol and introduces a way to achieve complete alpha-ManNAcA stereoselectivity.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Bijoyananda Mishra, Sujit Manmode, Gulab Walke, Saptashwa Chakraborty, Mahesh Neralkar, Srinivas Hotha
Summary: The chemical synthesis of complex oligosaccharides, especially those with hyper-branched structures and specific glycosidic bonds, is a challenging task due to factors such as reactivity of glycosyl donors and acceptors, and proper tuning of solvent/temperature/activator. In this study, a semi-conserved hyper-branched core tetrasaccharide motif was successfully synthesized from chloroviruses, involving a thorough study of various factors to achieve a stereoselective galactopyranosidic linkage.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Helle H. Trinderup, Sofie M. Andersen, Mads Heuckendorff, Henrik H. Jensen
Summary: The study showed that increasing the concentration and amount of triflic acid catalyst can enhance beta-selectivity in the reaction, while lowering temperature has a significant effect on the glycosylation outcome. The alpha/beta-ratio in the reaction with L-menthol as glycosyl acceptor was not affected by the molecular sieve pore size or NIS activator amount.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Ao Sun, Zipeng Li, Yuchao Wang, Shuai Meng, Xiao Zhang, Xiangbao Meng, Shuchun Li, Zhongtang Li, Zhongjun Li
Summary: This study presents an indirect method for the stereoselective synthesis of alpha-Kdo glycosides. The method utilizes a C3-p-tolylthio-substituted Kdo phosphite donor to achieve enhanced reactivity and complete alpha-stereocontrol. Various Kdo alpha-glycosides were successfully synthesized using this method. The orthogonality of the phosphite donor and thioglycoside donor was demonstrated through the one-pot synthesis of a trisaccharide. Furthermore, an efficient total synthesis route for a challenging 4,5-branched Kdo trisaccharide was highlighted. The high reactivity of the approach was further demonstrated by the synthesis of a highly crowded 4,5,7,8-branched Kdo pentasaccharide.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Kazuki Inaba, Yuna Naito, Mina Tachibana, Kazunobu Toshima, Daisuke Takahashi
Summary: A regioselective and beta-stereospecific d-/l-arabinofuranosylation method has been developed for efficient synthesis of biologically active natural glycosides. The method showed high regioselectivity and yield with complete beta-stereoselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Frank F. J. de Kleijne, Hidde Elferink, Sam J. Moons, Paul B. White, Thomas J. Boltje
Summary: The study characterizes low-populated, rapidly equilibrating mannosyl dioxanium ions using chemical exchange saturation transfer (CEST) NMR spectroscopy, revealing their structure and equilibration kinetics under relevant glycosylation conditions. Highly alpha-selective couplings were observed, suggesting glycosylation takes place via this elusive intermediate.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Zhen Wang, Ana Gimeno, Marta G. Lete, Herman S. Overkleeft, Gijsbert A. van der Marel, Fabrizio Chiodo, Jesus Jimenez-Barbero, Jeroen D. C. Codee
Summary: We report the first total synthesis of the Streptococcus pneumoniae serotype 1 (Sp1) oligosaccharide, which is a zwitterionic capsular polysaccharide carrying unstable O-acetyl esters. The synthesis was achieved by assembling trisaccharide building blocks in a highly stereoselective manner, up to the 9-mer level. The structure investigation revealed that the oligomers adopt a right-handed helical structure, with the acetyl esters exposed on the periphery and in close proximity of the neighboring AAT residues.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Thomas Hansen, Tim P. Ofman, Joey G. C. Vlaming, Ivan A. Gagarinov, Jessey van Beek, Tessa A. Gote, Jacoba M. Tichem, Gijs Ruijgrok, Herman S. Overkleeft, Dmitri V. Filippov, Gijsbert A. van der Marel, Jeroen D. C. Codee
Summary: By systematically studying the reactivity-stereoselectivity relationships of caryophyllose donor and acceptor glycosides, using experimental and computational techniques, we were able to design carbohydrate building blocks with the necessary properties to assemble mycobacterial lipooligosaccharide fragments of M. marinum.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Lai Mengnan, Wang Qiuyuan, Hua Min, Huang Nianyu, Yao Hui
Summary: An open-air stereoselective preparation of C-aryl fucosides and arabinosides was reported using 3,4-O-carbonate glycals and arylboronic acids. The configurations of products were determined by various analytical techniques. Competitive reactions demonstrated the compatibility of this method and its potential for the preparation of various C-glycosides through functionalization.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Yuna Guo, Nan Wang, Yihong Zhong, Wei Li, Yiran Li, Guyu Wang, Yunyan Yao, Yue Shi, Liusheng Chen, Xiaojian Wang, Huangxian Ju, Lin Ding
Summary: Cell surface engineering allows customization of cell interfaces with desirable properties and functions. However, methods for covalent labeling of cells that can simultaneously install multiple molecules with different functions are rare. In this study, a proximity catalytic covalent labeling platform enabled by aptamers was developed for multifunctional surface reconfiguration of target cells. The platform allows for selective binding and covalent labeling of target cells in mixed cell populations. It has the ability to perform a variety of manipulations on target cells, including labeling, tracking, assembly regulation, and surface remodeling. The platform also enables multiplexed covalent labeling, allowing the installation of two different reactive molecules simultaneously on the surface of target cells.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
