Stereoselective Phenylselenoglycosylation of Glycals Bearing a Fused Carbonate Moiety toward the Synthesis of 2-Deoxy-β-galactosides and β-Mannosides
作者:Shuai Meng、Wenhe Zhong、Wang Yao、Zhongjun Li
DOI:10.1021/acs.orglett.0c00732
日期:2020.4.17
A phenylselenoglycosylation reaction of glycal derivatives mediated by diphenyl diselenide and phenyliodine(III) bis(trifluoroacetate) under mild conditions is described. Stereoselective glycosylation has been achieved by installing fused carbonate on those glycals. 3,4-O-Carbonate galactals and 2,3-O-carbonate 2-hydroxyglucals are converted into corresponding glycosides in good yields with excellent
Diacyl Disulfide: A Reagent for Chemoselective Acylation of Phenols Enabled by 4-(<i>N</i>,<i>N</i>-Dimethylamino)pyridine Catalysis
作者:Hong-Xin Liu、Ya-Qian Dang、Yun-Fei Yuan、Zhi-Fang Xu、Sheng-Xiang Qiu、Hai-Bo Tan
DOI:10.1021/acs.orglett.6b02818
日期:2016.11.4
A general and excellent acylation reagent, diacyl disulfide, was uncovered for efficient ester formation enabled by DMAP (4-(N,N-dimethylamino)pyridine) catalysis. This protocol offered a promising synthetic platform on site-selective acylation of phenolic and primary aliphatic hydroxyl groups, which greatly expanded the realm of protecting group chemistry. The importance of the reagent was also reflected
AbstractHighly selective acylation of the phenolic hydroxy group can be achieved with (hydroxyalkyl)phenols carrying both alcoholic and phenolic hydroxyls by the use of vinyl carboxylates as acyl donors in the presence of rubidium fluoride. Graphical Abstract
A convenient preparation of glycosyl sulfoxides and its application to the synthesis of Salidroside epimer
作者:Qing Wang、Xiong Wei、Kaijun Liao、Hui Li、Xiangbao Meng、Zhongjun Li
DOI:10.1016/j.tetlet.2016.04.045
日期:2016.5
A facile and green approach for the preparation of glycosyl sulfoxides utilizing 30% aqueous H2O2 in phenol or acetic acid is described. Advantages include relatively mild conditions, high chemoselectivity, and good tolerance to a wide range of protective groups. Furthermore, the epimer of Salidroside containing one 1,2-cis glycosidic bond was synthesized in three steps in 90.1% overall yield using
描述了一种利用在苯酚或乙酸中的30%H 2 O 2水溶液制备糖基亚砜的简便且绿色的方法。优点包括相对温和的条件,较高的化学选择性和对多种保护基的良好耐受性。此外,使用吡喃葡萄糖基亚砜作为糖基供体,以30.1个步骤的总产率合成了含有1,2-顺式糖苷键的红景天苷的差向异构体。