67773-44-8Relevant academic research and scientific papers
Stereoselective β-mannosylations and β-rhamnosylations from glycosyl hemiacetals mediated by lithium iodide
McGarrigle, Eoghan M.,Pepe, Dionissia A.,Pongener, Imlirenla,Ruddy, Joseph J.
, p. 10070 - 10075 (2021/08/04)
Stereoselective β-mannosylation is one of the most challenging problems in the synthesis of oligosaccharides. Herein, a highly selective synthesis of β-mannosides and β-rhamnosides from glycosyl hemi-acetals is reported, following a one-pot chlorination,
Highly regioselective and stereoselective synthesis of C-Aryl glycosidesvianickel-catalyzedortho-C-H glycosylation of 8-aminoquinoline benzamides
Chen, Xi,Ding, Ya-Nan,Gou, Xue-Ya,Liang, Yong-Min,Luan, Yu-Yong,Niu, Zhi-Jie,Shi, Wei-Yu,Zhang, Zhe,Zheng, Nian
, p. 8945 - 8948 (2021/09/10)
C-Aryl glycosides are of high value as drug candidates. Here a novel and cost-effective nickel catalyzedortho-CAr-H glycosylation reaction with high regioselectivity and excellent α-selectivity is described. This method shows great functional group compatibility with various glycosides, showing its synthetic potential. Mechanistic studies indicate that C-H activation could be the rate-determining step.
Straightforward synthesis of protected 2-hydroxyglycals by chlorination-dehydrochlorination of carbohydrate hemiacetals
Choutka, Jan,Kratochvíl, Michal,Parkan, Kamil,Pohl, Radek,Zyka, Jakub
supporting information, (2020/08/24)
A straightforward and scalable method for the synthesis of protected 2-hydroxyglycals is described. The approach is based on the chlorination of carbohydrate-derived hemiacetals, followed by an elimination reaction to establish the glycal moiety. 1,2-dehy
Method for preparing halogenated sugar under mild conditions
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Paragraph 0052-0054, (2020/07/02)
The invention discloses a method for preparing halogenated sugar under mild conditions. The method comprises the following steps that an easily-prepared thioglycoside donor and a halogen simple substance or halogen intercompound undergo a reaction at room temperature to obtain the halogenated sugar (chlorine, bromine and iodine). The halogen simple substance or the halogen intercompound is commercial easily available iodine elementary substance, iodine bromide and iodine chloride. The method is suitable for various pyranoses and furanoses. The method has no limitation on a protecting group ofthe thioglycoside donor, and the protecting group can be an electron withdrawing group such as acetyl, benzoyl and the like, and can also be an electron donating group such as benzyl, silicon base andthe like. Meanwhile, the reaction can occur in various organic solvents such as dichloromethane, acetonitrile and methylbenzene. The preparation method of the halogenated sugar is simple, reaction conditions are mild, raw materials are easy to obtain, the application range is wide, the halogenated sugar is compatible with acid-labile groups such as isopropylidene ketal and silicon groups, and a pure product can be obtained by removing a solvent from the halogenated sugar which is not stable in the separation process.
Synthesis of Glycosyl Chlorides and Bromides by Chelation Assisted Activation of Picolinic Esters under Mild Neutral Conditions
Balzer, Paul G.,Blaszczyk, Stephanie A.,Duan, Xiyan,Ma, Zhi-Xiong,Simmons, Christopher J.,Stevens, Christopher M.,Tang, Weiping,Wang, Hao-Yuan,Wen, Peng,Ye, Wenjing,Yin, Dan
supporting information, (2020/02/28)
A general method has been developed for the formation of glycosyl chlorides and bromides from picolinic esters under mild and neutral conditions. Benchtop stable picolinic esters are activated by a copper(II) halide species to afford the corresponding products in high yields with a traceless leaving group. Rare β glycosyl chlorides are accessible via this route through neighboring group participation. Additionally, glycosyl chlorides with labile protecting groups previously not easily accessible can be prepared.
Establishment of Guidelines for the Control of Glycosylation Reactions and Intermediates by Quantitative Assessment of Reactivity
Chang, Chun-Wei,Wu, Chia-Hui,Lin, Mei-Huei,Liao, Pin-Hsuan,Chang, Chun-Chi,Chuang, Hsiao-Han,Lin, Su-Ching,Lam, Sarah,Verma, Ved Prakash,Hsu, Chao-Ping,Wang, Cheng-Chung
, p. 16775 - 16779 (2019/11/03)
Stereocontrolled chemical glycosylation remains a major challenge despite vast efforts reported over many decades and so far still mainly relies on trial and error. Now it is shown that the relative reactivity value (RRV) of thioglycosides is an indicator for revealing stereoselectivities according to four types of acceptors. Mechanistic studies show that the reaction is dominated by two distinct intermediates: glycosyl triflates and glycosyl halides from N-halosuccinimide (NXS)/TfOH. The formation of glycosyl halide is highly correlated with the production of α-glycoside. These findings enable glycosylation reactions to be foreseen by using RRVs as an α/β-selectivity indicator and guidelines and rules to be developed for stereocontrolled glycosylation.
Synthesis of glycosyl chlorides using catalytic Appel conditions
Pongener, Imlirenla,Nikitin, Kirill,McGarrigle, Eoghan M.
supporting information, p. 7531 - 7535 (2019/08/20)
The stereoselective synthesis of glycosyl chlorides using catalytic Appel conditions is described. Good yields of α-glycosyl chlorides were obtained using a range of glycosyl hemiacetals, oxalyl chloride and 5 mol% Ph3PO. For 2-deoxysugars treatment of the corresponding hemiacetals with oxalyl chloride without phosphine oxide catalyst also gave good yields of glycosyl chloride. The method is operationaly simple and the 5 mol% phosphine oxide by-product can be removed easily. Alternatively a one-pot, multi-catalyst glycosylation can be carried out to transform the glycosyl hemiacetal directly to a glycoside.
Iron(iii) chloride-catalyzed activation of glycosyl chlorides
Geringer, Scott A.,Demchenko, Alexei V.
supporting information, p. 9133 - 9137 (2019/01/03)
Glycosyl chlorides have historically been activated using harsh conditions and/or toxic stoichiometric promoters. More recently, the Ye and the Jacobsen groups showed that glycosyl chlorides can be activated under organocatalytic conditions. However, thos
Solvent-free synthesis of glycosyl chlorides based on the triphenyl phosphine/hexachloroacetone system
Traboni, Serena,Liccardo, Federica,Bedini, Emiliano,Giordano, Maddalena,Iadonisi, Alfonso
, p. 1762 - 1764 (2017/04/13)
Glycosyl chlorides, useful as glycosyl donors in glycoside synthesis and precursors in organic synthesis, can be easily prepared under solvent-free conditions by exposing a sugar hemiacetal to an equimolar mixture of PPh3 and hexachloroacetone
Regenerative glycosylation under nucleophilic catalysis
Nigudkar, Swati S.,Stine, Keith J.,Demchenko, Alexei V.
supporting information, p. 921 - 923 (2014/02/14)
This article describes 3,3-difluoroxindole (HOFox)-mediated glycosylation. The uniqueness of this approach is that both the in situ synthesis of 3,3-difluoro-3H-indol-2-yl (OFox) glycosyl donors and activation thereof can be conducted in a regenerative fashion as is a typical reaction performed under nucleophilic catalysis. Only a catalytic amount of the OFox imidate donor and a Lewis acid activator are present in the reaction medium. The OFox imidate donor is constantly regenerated upon its consumption until glycosyl acceptor has reacted.
