172847-85-7Relevant articles and documents
Triflic Imide-Catalyzed Glycosylation of Disarmed Glycosyl ortho-Isopropenylphenylacetates and ortho-Isopropenylbenzyl Thioglycosides
Qiao, Zhi,Wang, Peng,Ni, Jingxuan,Li, Dongwei,Sun, Yao,Li, Tiantian,Li, Ming
, (2022/01/19)
Glycosylation reaction involving the coupling of a glycosyl donor with a glycosyl acceptor is one of the cornerstones of chemical preparation of pure glycans and glycoconjugates of biological relevance. Catalytic glycosylation of glycosyl ester donors and thioglycosides is an attractive but underexplored topic in carbohydrate chemistry. Herein, triflic imide (Tf2NH)-catalyzed glycosylation of various O-, S-, and C-nucleophiles has been achieved using disarmed glycosyl ortho-isopropenylphenylacetates (GIPPAs) and ortho-isopropenylbenzyl thioglycosides as glycosylating agents. The reactions proceed under mild conditions to give the desired glycosides in good-to-excellent yields. Of particular note, the comparable reactivity for the α-isomers and the β-ones of GIPPAs is observed. The mechanistic investigation demonstrates that the isopropenyl group is essential for the reaction and its preferential protonation triggers the reaction. This work provides another member to the arsenals of glycosyl ester and thioglycoside donors suitable for acid-catalyzed glycosylation to create various glycosidic bonds.
Urea–hydrogen peroxide prompted the selective and controlled oxidation of thioglycosides into sulfoxides and sulfones
Singh, Adesh Kumar,Tiwari, Varsha,Mishra, Kunj Bihari,Gupta, Surabhi,Kandasamy, Jeyakumar
, p. 1139 - 1144 (2017/06/20)
A practical method for the selective and controlled oxidation of thioglycosides to corresponding glycosyl sulfoxides and sulfones is reported using urea–hydrogen peroxide (UHP). A wide range of glycosyl sulfoxides are selectively achieved using 1.5 equiv of UHP at 60 °C while corresponding sulfones are achieved using 2.5 equiv of UHP at 80 °C in acetic acid. Remarkably, oxidation susceptible olefin functional groups were found to be stable during the oxidation of sulfide.
Facile preparation of α-glycosyl iodides by in situ generated aluminum iodide: Straightforward synthesis of thio-, seleno-, and o-glycosides from unprotected reducing sugars
Weng, Shiue-Shien,Li, Chia-Ling,Liao, Chun-Sheng,Chen, Ting-An,Huang, Chao-Cheih,Hung, Kuo-Tung
, p. 429 - 440 (2012/06/01)
A facile and practical protocol was developed for the synthesis of glycosyl iodides using AlI3 generated in situ from cheap aluminum metal and molecular iodine. Furthermore, in combination with iodine-catalyzed per-O-acetylation, sequential synthesis of per-acetylated glycosyl iodides, per-acetylated thioglycosides, selenoglycoside, and O-glycosides from unprotected reducing sugars was also achieved with complete diastereocontrol in a one-pot version. Supplemental material is available for this article. Go to the publisher's online edition of Journal of Carbohydrate Chemistry to view the free supplemental file. Copyright Taylor & Francis Group, LLC.