Article
Chemistry, Multidisciplinary
Jacob M. A. van Hengst, Rik J. C. Hellemons, Wouter A. Remmerswaal, Koen N. A. van de Vrande, Thomas Hansen, Stefan van der Vorm, Hermen S. Overkleeft, Gijsbert A. van der Marel, Jeroen D. C. Codee
Summary: By systematically surveying 67 acceptor alcohols in glycosylation reactions, this study reveals how the reactivity of a carbohydrate acceptor depends on its configuration and substitution pattern, which greatly influences the yield and stereoselectivity of the reaction. The study demonstrates the influence of functional groups flanking the acceptor alcohol on its reactivity, highlighting the importance of both the nature and relative orientation. The empirical acceptor reactivity guidelines obtained will assist in the rational optimization of glycosylation reactions and serve as an important tool in oligosaccharide assembly.
Article
Biochemistry & Molecular Biology
Gefei Li, Masato Noguchi, Masaki Ishihara, Yuka Takagi, Marina Nagaki, Sachie Saito, Masashi Saito, Xin-shan Ye, Shin-ichiro Shoda
Summary: Chemical O-glycosylation is crucial for synthesizing sugar-containing molecules like glycolipids. However, traditional carbohydrate chemistry involves extensive use of protective groups, which is time-consuming and inefficient. In this study, a protecting-group-free glycosylation strategy using DBT-glycosides as glycosyl donors was developed. The method allows for direct synthesis of DBT-glycosyl donors from unprotected sugars in water. O-glycosylation of alcohols using DBT-glycosyl donors under mild hydrogenolytic conditions resulted in stereo-selective formation of alkyl glycosides with high yields.
CARBOHYDRATE RESEARCH
(2023)
Article
Biochemistry & Molecular Biology
Shogo Hamajima, Naoko Komura, Hide-Nori Tanaka, Akihiro Imamura, Hideharu Ishida, Tsuyoshi Ichiyanagi, Hiromune Ando
Summary: Chemical synthesis of Kdo-containing glycans is important for developing vaccines against pathogenic bacteria. The alpha-stereoselective glycosidation of Kdo has been achieved using a macrobicyclic donor. In this study, the protection of the 4-OH group and the use of a selectively removable booster allowed the synthesis of the dimeric Kdo sequence.
Article
Chemistry, Organic
Tao Luo, Qiang Zhang, Yang-Fan Guo, Zhi-Chao Pei, Hai Dong
Summary: Efficient strategies were developed in this study to synthesize 2-deoxysugars with exclusive alpha/beta-configuration. Four methyl 2-SAc glycosides were synthesized through the double serial inversion strategy and further converted into corresponding glycosyl donors. Glycosylation and synthesis of 2-deoxysugars were also investigated.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Plant Sciences
Yandong Song, Chunju Peng, Qinjiao Wu, Shijie Tao, Tingting Mei, Zhihong Sun, Zhaojiang Zuo, Chunyu Pan, Yufeng Zhou, Guomo Zhou
Summary: This study investigated the photosynthetic and isoprene emission characteristics of Moso bamboo at different culm ages. The results showed that the effect of culm age on isoprene emission was different from that on photosynthesis, indicating that the isoprene emission rate was higher in old bamboo compared to mature bamboo. Therefore, considering culm age is important when establishing an isoprene emission model of Moso bamboo, and attention should be paid to the management of bamboo age structure and timely felling of aged bamboo to reduce environmental risk.
FRONTIERS IN PLANT SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Xiaoqian Li, Zhi Ma, Rongkun Liu, Mattan Hurevich, You Yang
Summary: A green and efficient photolabile protecting group (PPG)-mediated glycosidation approach for the synthesis of 2-deoxy-glycosides is reported. Multiple oNBC groups in the 2-deoxy-glycosides can be completely cleaved by irradiation at 365 nm, resulting in the desired 2-deoxy-glycosides in an efficient manner. Oligosaccharides with three to six oNBC groups are effectively achieved based on this PPG-mediated glycosidation approach.
CHINESE JOURNAL OF 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, Organic
Claude Zoukimian, Remy Beroud, Didier Boturyn
Summary: In this study, we utilized the Hmb(off/on) protecting group for directed disulfide bond formation. By combining it with classical Trt, Acm, and Mob groups, we successfully synthesized NMB-1 and phlotoxin-1 toxins, demonstrating new orthogonal strategies for directed disulfide bond formation.
Article
Polymer Science
Jungyeon Kim, Valentin Beyer, C. Remzi Becer
Summary: In this study, we have developed a simple and elegant approach for the synthesis of poly(2-oxazoline) (POx) with pendant hydroxyl groups, using silyl protecting groups. By protecting the hydroxyl groups, well-defined polymers with tunable hydrophilicity and thermoresponsive behavior in water were obtained.
Article
Chemistry, Organic
Mayumi Takahashi, Andrzej Grajkowski, Brian M. Cawrse, Serge L. Beaucage
Summary: The implementation of protecting groups for the 2'-hydroxyl function of ribonucleosides remains challenging for RNA purification for therapeutic applications, requiring easy installation and efficient incorporation while minimizing impurities. Complete cleavage of the protecting group without the formation of side products or mutagenic adducts is crucial.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Shiqi Liu, Kun Zhang, Yutong Meng, Jiaxi Xu, Ning Chen
Summary: In this study, a highly efficient and convergent synthetic approach for the construction of tetrahydroisoquinoline-fused polyheterocycles is reported, utilizing a three-component formal [2 + 2 + 2] annulation process. The reaction involves the combination of 3,4-dihydroisoquinolines, CO2, and benzynes, with electron-rich 3,4-dihydroisoquinolines and electron-deficient benzynes showing greater reactivity. This method benefits from the convergent synthesis and the utilization of carbon dioxide, providing a valuable strategy for the facile synthesis of tetrahydroisoquinoline-fused polyheterocycles, with potential applications in the discovery and development of novel organic molecules.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Wouter A. Remmerswaal, Kas J. Houthuijs, Roel van de Ven, Hidde Elferink, Thomas Hansen, Giel Berden, Herman S. Overkleeft, Gijsbert A. van der Marel, Floris P. J. T. Rutjes, Dmitri V. Filippov, Thomas J. Boltje, Jonathan Martens, Jos Oomens, Jeroen D. C. Codee
Summary: The stereoselective introduction of glycosidic bonds is crucial for oligosaccharide synthesis, and the participation of neighboring or distal acyl groups is commonly used for stereoselectivity control. A recent study found that the 2,2-dimethyl-2-(ortho-nitrophenyl)acetyl (DMNPA) protection group exhibited enhanced stereoselective steering compared to other acyl groups. Through glycosylation reactions and infrared ion spectroscopy (IRIS) combined with isotopic labeling and population analysis, it was determined that the enhanced stereoselectivity of the DMNPA group is not a result of the direct participation of the nitro moiety, but rather due to the stabilization of a dioxolenium ion formed by the nitro group.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Konstantinos Grammatoglou, Madara Darzina, Aigars Jirgensons
Summary: This article discusses the C-H deprotonation of 6-methylpyridyl-2-methyl protected tetrazoles using the turbo-Grignard reagent, as well as a method for cleaving the protecting group under reductive electrochemical conditions.
Article
Chemistry, Multidisciplinary
Jay Tromans, Bian Zhang, Bernard T. Golding
Summary: A new benzyl-type protecting group (DIMON) has been developed for the selective removal of hydroxyl functions under oxidative conditions without damaging polyunsaturated fatty acyl groups. Its application has led to the first synthesis of an ether phospholipid containing a specific acyl group.
CHEMICAL COMMUNICATIONS
(2023)
Article
Biochemistry & Molecular Biology
Xing-Yong Liang, Jing Yang, Zhong-Hao Qiu, Lei Wang, Todd L. Lowary, Hua-Jun Shawn Fan
Summary: This study developed a method for preparing 2-deoxy-2-azido-alpha-D-galactopyranosidic bonds using donor 5, which exhibited good to excellent alpha-selectivity attributed to specific protecting groups. The presence of TBDPS on 3-O and benzylidenyl on 4,6-di-O enhanced the activity of the thioglycoside and improved stereoselectivity, as demonstrated through the synthesis of a alpha-galactosamine-containing pentasaccharide 26.
CARBOHYDRATE RESEARCH
(2021)