Stereoselective Synthesis of 2-C-Branched (Acetylmethyl) Oligosaccharides and Glycoconjugates: Lewis Acid-Catalyzed Glycosylation from 1,2-Cyclopropaneacetylated Sugars

	Stereoselective Synthesis of 2-C-Branched (Acetylmethyl) Oligosaccharides and Glycoconjugates: Lewis Acid-Catalyzed Glycosylation from 1,2-Cyclopropaneacetylated Sugars
	Tian, Qiang ; Dong, Liang ; Ma, Xiaofeng ; Xu, Liyan ; Hu, Changwei ; Zou, Wei ; Shao, Huawu
刊名	JOURNAL OF ORGANIC CHEMISTRY
	2011
卷号	76 期号:4 页码:1045-1053
ISSN号	0022-3263
通讯作者	Hu, Changwei ; Shao, Huawu
产权排序	1
英文摘要	1,2-Cyclopropaneacetylated sugars as glycosyl donors reacted with a series of glycosyl acceptors (monosaccharides, amino acids, and other alcohols) in the presence of Lewis acid to produce oligosaccharides and glycoconjugates containing 2-C-acetylmethylsugars. Galactosyl donor gave good to excellent alpha-selectivities with TMSOTf as a catalyst, whereas galactosyl donor offered moderate to good beta-selectivities when BF3 center dot Et2O was used as a catalyst. However, glucosyl donors produced beta-exclusive selectivity under both conditions. The stereoselectivities of glycosylation depend on the reactivity of donor sugars and Lewis acid catalyst, which effectively dictated the glycosylation pathways. The evidence suggests that galactosyl donors (e.g., 7) can undergo S(N)1 pathway with a strong Lewis acid (TMSOTf) and S(N)2 pathway under BF3 center dot Et2O, whereas the glucosyl donors (e.g., 8 and 10) followed S(N)2 pathway. The stereoselectivity was also consequential to the formation of a C2'-acetal intermediate formed via the 2-C-acetylmethyl group and the anomeric carbonium intermediate in glycosylation.
学科主题	Chemistry
收录类别	SCI
资助信息	Chinese Academy of Sciences; National Science Foundation of China[20972151]
语种	英语
WOS记录号	WOS:000287122600004
公开日期	2012-11-09
内容类型	期刊论文
源URL	[http://210.75.237.14/handle/351003/23559]
专题	成都生物研究所_天然产物研究
推荐引用方式 GB/T 7714	Tian, Qiang,Dong, Liang,Ma, Xiaofeng,et al. Stereoselective Synthesis of 2-C-Branched (Acetylmethyl) Oligosaccharides and Glycoconjugates: Lewis Acid-Catalyzed Glycosylation from 1,2-Cyclopropaneacetylated Sugars[J]. JOURNAL OF ORGANIC CHEMISTRY,2011,76(4):1045-1053.
APA	Tian, Qiang.,Dong, Liang.,Ma, Xiaofeng.,Xu, Liyan.,Hu, Changwei.,...&Shao, Huawu.(2011).Stereoselective Synthesis of 2-C-Branched (Acetylmethyl) Oligosaccharides and Glycoconjugates: Lewis Acid-Catalyzed Glycosylation from 1,2-Cyclopropaneacetylated Sugars.JOURNAL OF ORGANIC CHEMISTRY,76(4),1045-1053.
MLA	Tian, Qiang,et al."Stereoselective Synthesis of 2-C-Branched (Acetylmethyl) Oligosaccharides and Glycoconjugates: Lewis Acid-Catalyzed Glycosylation from 1,2-Cyclopropaneacetylated Sugars".JOURNAL OF ORGANIC CHEMISTRY 76.4(2011):1045-1053.