Article
Chemistry, Multidisciplinary
Yuanyuan Bai, Xiaohong Yang, Hai Yu, Xi Chen
Summary: Innovation in process development is crucial for the industrial and laboratory production of organic compounds, such as HMOs, through biocatalysis. A substrate and process engineering strategy called MSOPME design allows for efficient synthesis of HMOs, including long-chain oligosaccharides, without the need for isolation of intermediate products. The method can be scaled up for large-scale synthesis and automation.
Article
Chemistry, Multidisciplinary
Xiaona Li, Cristina Di Carluccio, He Miao, Lvfeng Zhang, Jintao Shang, Antonio Molinaro, Peng Xu, Alba Silipo, Biao Yu, You Yang
Summary: We report a promoter-controlled cycloglycosylation approach for the synthesis of cyclic α-(1→6)-linked mannosides up to a length of 32 units. The method relies on the role of a gold(I) complex in the proper preorganization of the ultra-large cyclic transition state. NMR experiments and a computational study revealed that the cyclic 2-mer, 4-mer, 8-mer, 16-mer, and 32-mer mannosides adopted different conformational states and shapes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Chaoyu Hu, Shengjie Wu, Fei He, Deqin Cai, Zhuojia Xu, Wenjing Ma, Yating Liu, Bangguo Wei, Tiehai Li, Kan Ding
Summary: Bioactive polysaccharides are potential target molecules for drug development, but the synthesis of branched complex polysaccharides with well-defined structures is challenging. In this study, a highly branched heptadecasaccharide moiety of a native bioactive polysaccharide from Carthamus tinctorius L. was efficiently synthesized, and its biological activity in targeting galectin-3 and inhibiting pancreatic cancer cell growth was demonstrated.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Peng Wen, Peijing Jia, Qiuhua Fan, Bethany J. McCarty, Weiping Tang
Summary: A streamlined iterative assembly of thio-oligosaccharides was developed by aqueous glycosylation, efficiently synthesizing 1,2-trans S-glycosides with high chemo- and stereoselectivity at room temperature. The method was successfully applied to the synthesis of a trimannoside moiety of N-linked glycans core region.
Article
Chemistry, Organic
Ganesh Shrestha, Matteo Panza, Yashapal Singh, Keith J. Stine, Alexei V. Demchenko
Summary: In this study, the activation process of N-alkylated SInR derivatives was investigated by NMR, leading to the discovery of different activation pathways for SIn and SInR derivatives. The orthogonality between SInR leaving groups and thioglycosides, as well as the selective activation of thioimidates over SInR glycosides, were also examined.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Samim Sahaji, Pradip Shit, Anup Kumar Misra
Summary: A convergent [4+2] stereoselective block glycosylation strategy was developed for the synthesis of the hexasaccharide repeating unit of Klebsiella K19 strain's capsular polysaccharide with high yield. Temporary alkyl protecting group p-methoxybenzyl (PMB) was used and removed through glycosylation conditions. Thioglycoside served as a glycosyl acceptor in an orthogonal glycosylation reaction. TEMPO-mediated selective oxidation and thiophilic promoter N-iodosuccinimide (NIS) in combination with perchloric acid supported over silica (HClO4-SiO2) were used.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Organic
Serena Traboni, Emiliano Bedini, Alba Silipo, Giulia Vessella, Alfonso Iadonisi
Summary: The novel glycosylation method reported in this study, based on the direct activation of per-O-acylated donors using methanesulfonic acid as a catalyst in the absence of solvents, offers a sustainable and environmentally friendly approach for the synthesis of carbohydrates and their derivatives. The method not only avoids the use of toxic and polluting organic solvents, but also shows high stereoselectivity and efficiency in obtaining desired glycosides.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Swapan Kumar Jana, Pradip Shit, Anup Kumar Misra
Summary: In this study, the pentasaccharide repeating unit rich in 2-acetamidosugars corresponding to the O-antigenic polysaccharide from entero-pathogenic E. coli was successfully synthesized as the p-me-thoxyphenyl glycoside using a sequential glycosylation strategy. The key components of the synthetic strategy included regioselective glycosylation, use of a single monosaccharide intermediate in multiple glycosylations, and the use of thioglycosides as glycosyl donors in the presence of a combination of N-iodosuccinimide and perchloric acid supported over silica.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Multidisciplinary
Yashapal Singh, Samira Escopy, Melanie Shadrick, Mithila D. Bandara, Keith J. Stine, Alexei V. Demchenko
Summary: Human milk oligosaccharides (HMO) are an active area of research in glycoscience and nutrition due to their involvement in infant development and potential disease prevention. This study reports the chemical synthesis of two core hexasaccharides found in human milk, pLNH and pLNnH, using a 3+3 convergent coupling strategy.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Biochemistry & Molecular Biology
Mei-Huei Lin, Jakob B. Wolf, Eric T. Sletten, Dario Cambie, Jose Danglad-Flores, Peter H. Seeberger
Summary: This article discusses the complexity of synthesizing defined oligosaccharides and introduces several enabling technologies that have been introduced in the past two decades to facilitate their synthesis. The application of automated glycan assembly, flow chemistry, and data science are highlighted as examples, emphasizing how the synergies between these technologies can further advance the field of glycochemistry.
Article
Chemistry, Multidisciplinary
Xiaona Li, You Yang
Summary: Automated chemical solid-phase synthesis is a reliable and efficient automation platform for synthesizing glycans. Automated Glycan Assembly (AGA), as a key breakthrough in the field, has evolved from a proof-of-concept to a robust technology for streamlined production of various glycans. In addition, HPLC-assisted automated synthesis shows promising potential in accessing glycans.
CHINESE JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Xian-Yang Zhou, Ling-Xin Li, Zhen Zhang, Shi-Chao Duan, Ying-Wen Huang, Yi-Yang Luo, Xiao-Dong Mu, Zhi-Wei Chen, Yong Qin, Jing Hu, Jian Yin, Jin-Song Yang
Summary: Acinetobacter baumannii poses a serious threat to global health, and its lipopolysaccharide (LPS) has been found to have antigenic properties. Research has identified a potential antigenic epitope in one of the branches of the LPS, which is attractive for the development of carbohydrate vaccines against A. baumannii.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Shuo Zhang, Mauro Sella, Julinton Sianturi, Patricia Priegue, Dacheng Shen, Peter H. Seeberger
Summary: Researchers synthesized oligosaccharides resembling the capsular polysaccharides of Streptococcus suis serotypes and identified lead antigens for the development of semi-synthetic S. suis serotypes 2 and 9 glycoconjugate veterinary vaccines by screening blood from infected pigs.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Zhi Qiao, Dongwei Li, Jingru Gao, Zijiao Hou, Ningjie Yan, Ni Song, Peng Wang, Ming Li
Summary: This study describes a novel and efficient approach to synthesizing rare L-hexoses from readily available and inexpensive D-sugars. It involves the transformation of sugar rings through radical decarboxylative fluorination of uronic acids, allowing for the installation of anomeric hydroxymethyl group under mild conditions and C1-to-C5 switch. The power of this protocol is demonstrated by the assembly of a pentasaccharide repeating unit of Pseudomonas ATCC 31554 extracellular polysaccharide.
CHINESE JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Matheus A. Meirelles, Jean-Louis Reymond
Summary: This study presents an optimized synthesis method for a probe used in studying protein N-glycosylation in eukaryotic cells. The yields and reaction times of three phosphate coupling steps were improved by adjusting reagents and conditions. An efficient purification protocol was also developed to obtain the pure product.
HELVETICA CHIMICA ACTA
(2023)
Article
Biochemistry & Molecular Biology
Ganesh Shrestha, Gustavo A. Kashiwagi, Keith J. Stine, Alexei Demchenko
Summary: The article presented an improved synthesis method for a common 3-OH glycosyl acceptor, utilizing Koto's selective benzylation protocol followed by acylation-purification-deacylation sequence. Despite involvingadditional manipulations, this approach offers consistent results and is superior to other indirect strategies. In addition to obtaining 3-OH acceptor, a minor quantity of 4-OH acceptor was also obtained.
CARBOHYDRATE RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Samira Escopy, Yashapal Singh, Keith J. Stine, Alexei V. Demchenko
Summary: As the 21st century unfolds with rapid changes, new challenges have arisen in research and development. This article introduces a solution phase batch synthesis method based on the HPLC platform, which enables sequential synthesis of multiple oligosaccharides and automates the process.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Organic
Ganesh Shrestha, Matteo Panza, Yashapal Singh, Keith J. Stine, Alexei V. Demchenko
Summary: In this study, the activation process of N-alkylated SInR derivatives was investigated by NMR, leading to the discovery of different activation pathways for SIn and SInR derivatives. The orthogonality between SInR leaving groups and thioglycosides, as well as the selective activation of thioimidates over SInR glycosides, were also examined.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Medicinal
Olivia Slater, Kapur B. Dhami, Ganesh Shrestha, Maria Kontoyianni, Michael R. Nichols, Alexei V. Demchenko
Summary: This study reports the development of a new Lipid-A analogue lacking a disaccharide core but still exhibiting potent antagonistic activity against LPS-induced inflammation. Computational, synthetic, and biological studies revealed new structural determinants of these simplified analogues.
ACS INFECTIOUS DISEASES
(2022)
Review
Chemistry, Multidisciplinary
Yashapal Singh, Scott A. Geringer, Alexei V. Demchenko
Summary: Advances in synthetic carbohydrate chemistry have improved access to common glycans, but challenges remain. Glycosyl halides play a crucial role in glycosylation.
Article
Chemistry, Organic
Scott A. Geringer, Gustavo A. Kashiwagi, Alexei V. Demchenko
Summary: The reverse orthogonal strategy, using orthogonal protecting groups that can be removed during glycosylation, offers a new approach to simplify glycan assembly. New combinations of orthogonal leaving and protecting groups have been discovered, improving the efficiency of this strategy.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Melanie Shadrick, Keith J. Stine, Alexei V. Demchenko
Summary: This study presents a stereoselective synthesis of alpha-galactosides using galactosyl chlorides as glycosyl donors under the catalytic system of Ag2SO4 and Bi(OTf)3.
BIOORGANIC & MEDICINAL CHEMISTRY
(2022)
Article
Chemistry, Analytical
Palak Sondhi, Dharmendra Neupane, Jay K. Bhattarai, Alexei V. Demchenko, Keith J. Stine
Summary: This article reports a simple and robust method for the fabrication of hierarchical and bimodal nanoporous gold electrodes and analyzes their potential application in biosensor development. The hierarchical pore structure was successfully created using electrochemical alloying and dealloying processes, and the performance of the electrode was evaluated using various characterization techniques.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Mariya Novakova, Anupama Das, Catherine Alex, Alexei V. V. Demchenko
Summary: This study presents a streamlined synthesis of a rare sugar D-altrosamine and investigates the glycosylation of different glycosyl acceptors using differentially protected altrosamine donors. High facial stereoselectivity is achieved through the H-bond-mediated aglycone delivery (HAD) pathway with 3-O-picoloyl donors and reactive glycosyl acceptors. In contrast, glycosidations with altrosamine donors equipped with the 3-O-benzoyl group show poor stereoselectivity.
FRONTIERS IN CHEMISTRY
(2022)
Review
Materials Science, Multidisciplinary
Palak Sondhi, Dhanbir Lingden, Jay K. K. Bhattarai, Alexei V. V. Demchenko, Keith J. J. Stine
Summary: Nanoporous gold (np-Au) has unique properties that make it attractive for therapeutic applications, including high surface area-to-volume ratio, tunable shape and size, ability to interact with organic molecules including drugs, and biocompatibility. The photothermal effect of np-Au nanostructures can be utilized for controlled drug release and local heating for cancer cell destruction. Despite its enormous potential, research on the therapeutical use of np-Au is still in its early stages.
Article
Chemistry, Multidisciplinary
Ashley Dent, Samira Escopy, Alexei V. Demchenko
Summary: This study presents a novel method for activating thioglycosides without using a glycosyl halide intermediate. It utilizes a combination of a silver salt, an acid additive, and molecular iodine. The enhanced stereocontrol is achieved through the H-bond mediated aglycone delivery (HAD) method, and the extended trisaccharide synthesis is achieved via a series of deprotection and glycosylation steps.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Biochemistry & Molecular Biology
Nicholas Forsythe, Leah Liu, Gustavo A. Kashiwagi, Alexei V. Demchenko
Summary: A novel method for activating thioglycosides and thioimidates using benzyl trichloroacetimidate in the presence of catalytic triflic acid is reported. Excellent yields were achieved with reactive substrates, but the efficiency of reactions with unreactive glycosyl donors and/or acceptors was modest.
CARBOHYDRATE RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Yashapal Singh, Samira Escopy, Melanie Shadrick, Mithila D. Bandara, Keith J. Stine, Alexei V. Demchenko
Summary: Human milk oligosaccharides (HMO) are an active area of research in glycoscience and nutrition due to their involvement in infant development and potential disease prevention. This study reports the chemical synthesis of two core hexasaccharides found in human milk, pLNH and pLNnH, using a 3+3 convergent coupling strategy.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Nicholas P. Forsythe, Emma R. Mize, Gustavo A. Kashiwagi, Alexei V. Demchenko
Summary: This study reports a streamlined synthetic approach for the production of superarmed glycosyl donors with various leaving groups, and showcases the applicability of this method in the direct formation of disaccharides.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Multidisciplinary
Alessio Romerio, Ana Rita Franco, Melanie Shadrick, Mohammed Monsoor Shaik, Valentina Artusa, Alice Italia, Federico Lami, Alexei V. Demchenko, Francesco Peri
Summary: This study developed a series of structurally simplified synthetic TLR4 agonists as vaccine adjuvants by mimicking the lipid A portion of LPS. Introducing a monosaccharide unit in C6 can improve the target affinity of the new molecules, which showed higher activity and selectivity in vitro.
