358681-51-3Relevant academic research and scientific papers
Concise Synthesis of 1-Thioalkyl Glycoside Donors by Reaction of Per-O-acetylated Sugars with Sodium Alkanethiolates under Solvent-Free Conditions
Dong, Hai,Feng, Guang-Jing,Guo, Yang-Fan,Liu, Chun-Yang,Luo, Tao
, (2022/02/07)
A relatively green method for synthesizing 1-thioalkyl glycosides has been developed, where sodium alkanethiolates were used to react with per-O-acetylated sugars instead of odorous alkyl mercaptans in the presence of BF3·Et2O without the use of solvents under mild conditions. Furthermore, we found that 1,2-trans-β-thioglycosides can be converted into corresponding 1,2-cis-α-thioglycosides in the presence of trifluoromethanesulfonic acid in nonpolar solvents under mild conditions. This provides a simple and efficient new approach for synthesizing challenging 1,2-cis-α-thioglycosides.
Triflic acid-mediated synthesis of thioglycosides
Escopy, Samira,Singh, Yashapal,Demchenko, Alexei V.
supporting information, p. 8379 - 8383 (2019/09/30)
An efficient synthesis of thioglycosides from per-acetates in the presence of triflic acid is described. The developed protocol features high reaction rates and product yields. Some reactive sugar series give high efficiency in the presence of sub-stoichiometric trifluoromethanesulfonic acid (TfOH) in contrast to other known protocols that require multiple equivalents of Lewis acids to reach high conversion rates.
Synthesis of triazolyl-linked polysialic acids
Xiong, De-Cai,Zhou, Yichuan,Cui, Yuxin,Ye, Xin-Shan
supporting information, p. 9405 - 9412 (2015/03/05)
A new approach for the synthesis of triazolyl-linked α-(2-9) oligosialic acids by iterative copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC) and desilylation has been developed. By using propargyl α-sialoside 5 and trimethylsilylated-propargyl 9-azido-α-sialoside 3 as building blocks, triazolyl-linked α-(2-9) di- to octa-sialic acids were constructed in good to moderate yields. Finally, the pseudo-α-(2-9)-oligosialic acids were obtained very smoothly via O-deprotection. The oligosialic acids with a triazolyl-linkage represent a new type of pseudooligosialic acids. This protocol may find applications in the preparation of oligosialic acid analogues with biological importance.
Comparative studies on the O-sialylation with four different α/β-oriented (N-acetyl)-5-N,4-O-carbonyl-protected p-toluenethiosialosides as donors
Zhang, Xiao-Tai,Gu, Zhen-Yuan,Xing, Guo-Wen
, p. 1 - 7 (2014/03/21)
Four types of 5-N,4-O-carbonyl-protected p-toluenethiosialosides were synthesized and their couplings with different acceptors were thoroughly investigated. The results indicate that the sialyl donor structure, the amount of glycosyl acceptor, and the detailed promotion conditions have great influence on the sialylation stereoselectivties and product yields. Under the (p-Tol)2SO/Tf2O activation conditions, the glycosylations with simple alcohols provided declined α-selectivities and higher yields with increasing the amounts of acceptors from 1.1 equiv to 2.0 equiv. However, the outcome of same sialylation was independent of the relative amounts of sugar alcohol acceptors. With NIS/TfOH as promoter, the α-selectivities of the sialylations were significantly improved compared with the cases activated by (p-Tol)2SO/Tf2O. In general, the difference in configuration of N-acetylated sialyl donors (D2 and D4) has little effect on the sialylation yield and stereoselectivity. In contrast, the N-deacetylated α/β sialyl donors (D1 and D3) show complex sialylation profiles with different acceptors.
Solvent-free synthesis of thioglycosides by ball milling
Ramrao Patil, Premanand,Ravindranathan Kartha
experimental part, p. 953 - 956 (2010/04/23)
Thioglycosides have been prepared in excellent yields by three different routes from a range of readily available glycosyl halides under solvent-free conditions employing a planetary ball mill.
Versatile acetylation of carbohydrate substrates with bench-top sulfonic acids and application to one-pot syntheses of peracetylated thioglycosides
Chao, Chin-Sheng,Chen, Min-Chun,Lin, Shih-Che,Mong, Kwok-Kong T.
, p. 957 - 964 (2008/09/17)
Inexpensive and readily available sulfonic acids, p-toluenesulfonic acid, and sulfuric acid are versatile and efficient catalysts for the peracetylation of a broad spectrum of carbohydrate substrates in good yield and in a practical time frame. Three appealing features in sulfonic acid-catalyzed acetylation of free sugars were explored including (1) suppression of furanosyl acetate formation for d-galactose and l-fucose; (2) high yielding chemoselective acetylation of sialic acid under appropriate conditions; and (3) peracetylation of amino sugars with different amino protecting functions. Simple one-pot two step acetylation-thioglycosidation methods for the expeditious synthesis of p-tolyl per-O-acetyl thioglycosides were also delineated.
Conversion of the carboxy group of sialic acid donors to a protected hydroxymethyl group yields an efficient reagent for the synthesis of the unnatural beta-linkage
Ye,Huang,Wong
, p. 974 - 975 (2007/10/03)
New sialyl donors with a protected hydroxymethyl group at the anomeric center are over 1000 times more reactive than the normal ester containing sialylation reagent and give excellent yield (> 90%) with unusually high β-stereoselectivity in sialylation.
