136984-89-9Relevant articles and documents
Direct dehydrative glycosylation catalyzed by diphenylammonium triflate
Hsu, Mei-Yuan,Lam, Sarah,Lin, Mei-Huei,Lin, Su-Ching,Wang, Cheng-Chung,Wu, Chia-Hui
supporting information, (2020/03/13)
Methods for direct dehydrative glycosylations of carbohydrate hemiacetals catalyzed by diphenylammonium triflate under microwave irradiation are described. Both armed and disarmed glycosyl-C1-hemiacetal donors were efficiently glycosylated in moderate to excellent yields without the need for any drying agents and stoichiometric additives. This method has been successfully applied to a solid-phase glycosylation.
Remote Participation during Glycosylation Reactions of Galactose Building Blocks: Direct Evidence from Cryogenic Vibrational Spectroscopy
Marianski, Mateusz,Mucha, Eike,Greis, Kim,Moon, Sooyeon,Pardo, Alonso,Kirschbaum, Carla,Thomas, Daniel A.,Meijer, Gerard,von Helden, Gert,Gilmore, Kerry,Seeberger, Peter H.,Pagel, Kevin
supporting information, p. 6166 - 6171 (2020/03/10)
The stereoselective formation of 1,2-cis-glycosidic bonds is challenging. However, 1,2-cis-selectivity can be induced by remote participation of C4 or C6 ester groups. Reactions involving remote participation are believed to proceed via a key ionic intermediate, the glycosyl cation. Although mechanistic pathways were postulated many years ago, the structure of the reaction intermediates remained elusive owing to their short-lived nature. Herein, we unravel the structure of glycosyl cations involved in remote participation reactions via cryogenic vibrational spectroscopy and first principles theory. Acetyl groups at C4 ensure α-selective galactosylations by forming a covalent bond to the anomeric carbon in dioxolenium-type ions. Unexpectedly, also benzyl ether protecting groups can engage in remote participation and promote the stereoselective formation of 1,2-cis-glycosidic bonds.
Photo-induced glycosylation using a diaryldisulfide as an organo-Lewis photoacid catalyst
Iibuchi, Naoto,Eto, Takahiro,Aoyagi, Manabu,Kurinami, Reiji,Sakai, Hayato,Hasobe, Taku,Takahashi, Daisuke,Toshima, Kazunobu
supporting information, p. 851 - 855 (2020/02/15)
Photo-induced glycosylations of several acceptors with trichloroacetimidate donors using bis(2-naphthyl)disulfide as an organo-Lewis photoacid (LPA) catalyst proceeded effectively to give the corresponding glycosides in good to high yields. In addition, t
A visible light promoted O-glycosylation with glycosyl trichloroacetimidates using eosin Y as an organo photoacid
Li, Hongfang,Liu, Jiao,Ni, Guanghui,Wang, Haimei,Yin, Shan
, (2020/03/06)
A photoacid catalyzed O-glycosylation of alcohols with glycosyl trichloroacetimidates in the presence of commercially available phenolic photoacids, fluorescein, 4′,5′-dibromo-fluorescein, and eosin Y under visible light irradiation by blue LEDs was devel
Visible light promoted method for constructing O-glycoside bonds
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Paragraph 0028-0029, (2020/07/13)
The invention discloses a visible light promoted method for constructing O-glycoside bonds. Glycosyl trichloroacetimidate is taken as a donor, and phenolic compounds are taken as a photocatalyst; a molecular sieve is added; and the O-glycoside bonds are g
N-benzoylglycine/thiourea cooperative catalyzed stereoselective O-glycosidation: Activation of O-glycosyl trichloroacetimidate donors
Dubey, Atul,Sangwan, Rekha,Mandal, Pintu Kumar
, p. 123 - 129 (2019/04/17)
A new practical utility for β-stereoselective glycosylation via activation of O-glycosyl trichloroacetimidate donors using N-benzoylglycine/thiourea cooperative catalysis has been demonstrated. This method represents the first instance where amino acid derived N-benzoylglycine is used as a catalyst for O–glycosylation under mild reaction conditions at ambient temperature. NMR spectroscopy studies suggest that thiourea cocatalyst exhibit a cooperative behaviour that has a strong effect on the reaction rate, yield, and the β-selectivity.
An Unexpected FeCl 3/C-Catalyzed β-Stereoselective Glycosylation in the Presence of the C(2)-Benzyl Group
Guo, Hong,Li, Juan,Si, Wenshuai,Tang, Jie,Tang, Tianjun,Wang, Zhongfu,Yang, Guofang,Zhang, Jianbo
, p. 2984 - 3000 (2019/07/22)
An efficient and completely β-stereoselective glycosylation that did not rely on neighboring group participation is described using 2-20 molpercent FeCl 3 /C as the catalyst and benzylated propargyl glycosides as the donors to reach yields up to 96percent under mild condition. With an octatomic-ring intermediate at the α-face of FeCl 3 /C with alkyne of propargyl glycosides, a panel of aglycones comprising aliphatic, alicyclic, unsaturated alcohols, halogenated alcohols, and phenols with different substitution were examined successfully for the exclusive β-stereoselective glycosylation reaction.
Gold(III)-Catalyzed Glycosylation using Phenylpropiolate Glycosides: Phenylpropiolic Acid, An Easily Separable and Reusable Leaving Group
Shaw, Mukta,Thakur, Rima,Kumar, Amit
, p. 589 - 605 (2019/01/14)
An efficient and operationally simple gold(III)-catalyzed glycosylation protocol was developed using newly synthesized benchtop stable phenylpropiolate glycosyl (PPG) donors. Gold(III)-catalyzed activation of PPGs proceeds well with various carbohydrate a
An Empirical Understanding of the Glycosylation Reaction
Chatterjee, Sourav,Moon, Sooyeon,Hentschel, Felix,Gilmore, Kerry,Seeberger, Peter H.
supporting information, p. 11942 - 11953 (2018/09/27)
Reliable glycosylation reactions that allow for the stereo- and regioselective installation of glycosidic linkages are paramount to the chemical synthesis of glycan chains. The stereoselectivity of glycosylations is exceedingly difficult to control due to the reaction's high degree of sensitivity and its shifting, simultaneous mechanistic pathways that are controlled by variables of unknown degree of influence, dominance, or interdependency. An automated platform was devised to quickly, reproducibly, and systematically screen glycosylations and thereby address this fundamental problem. Thirteen variables were investigated in as isolated a manner as possible, to identify and quantify inherent preferences of electrophilic glycosylating agents (glycosyl donors) and nucleophiles (glycosyl acceptors). Ways to enhance, suppress, or even override these preferences using judicious environmental conditions were discovered. Glycosylations involving two specific partners can be tuned to produce either 11:1 selectivity of one stereoisomer or 9:1 of the other by merely changing the reaction conditions.
Stereocontrolled glycoside synthesis by activation of glycosyl sulfone donors with scandium(III) triflate
Xolin, Amandine,Losa, Romain,Kaid, Aicha,Tresse, Cédric,Beau, Jean-Marie,Boyer, Fran?ois-Didier,Norsikian, Stéphanie
, p. 325 - 335 (2018/01/12)
The activation of aryl glycosyl sulfone donors has been achieved using scandium(iii) triflate and has led to the selective preparation of α-mannosides resulting from a post-glycosylation anomerization.
