1037510-19-2Relevant academic research and scientific papers
Directing effect by remote electron-withdrawing protecting groups at O-3 or O-4 position of donors in glucosylations and galactosylations
Baek, Ju Yuel,Kwon, Hea-Won,Myung, Se Jin,Park, Jung Jun,Kim, Mi Young,Rathwell, Dominea C.K.,Jeon, Heung Bae,Seeberger, Peter H.,Kim, Kwan Soo
, p. 5315 - 5320 (2015/07/15)
Glucosylations and galactosylations of various acceptors with donors possessing an electron-withdrawing benzylsulfonyl, benzoyl, or acetyl group at the O-3 or O-4 position were performed. A β-directing effect by the benzylsulfonyl group at O-3 of the glucosyl donors and by the benzylsulfonyl and acyl groups at O-4 of the glucosyl donors was observed. In contrast, acyl groups at O-3 of the glucosyl donors and acyl groups at O-3 and O-4 of the galactosyl donors exhibited an α-directing effect. The α-directing effect is partly considered to remote participation of the acyl groups, whereas the β-directing effect is somewhat attributed to the SN2-like reaction of the acceptor with the glycosyl triflate or the contact ion pair, which is stabilized by remote electron-withdrawing groups. Further evidence for the stability of the α-glycosyl triflates was determined by a low-temperature NMR study.
Direct glycosylation with anomeric hydroxy sugars by activation with 3-fluorophthalic anhydride and trifluoromethanesulfonic anhydride
Baek, Ju Yuel,Lee, Bo-Young,Pal, Rita,Lee, Won-Yong,Kim, Kwan Soo
supporting information; experimental part, p. 6250 - 6254 (2011/03/17)
An efficient and direct one-pot glycosylation method using anomeric hydroxy sugars as glycosyl donors, employing 3-fluorophthalic anhydride and triflic anhydride as activating agents, has been developed. The present glycosylation utilizing 3-fluorophthali
Stereoselective synthesis of α-glucosides by neighbouring group participation via an intermediate thiophenium ion
Cox, Daniel J.,Fairbanks, Antony J.
experimental part, p. 773 - 780 (2009/09/30)
The use of a 2-O-(thiophen-2-yl)methyl protecting group allows highly stereoselective α-glucosylation of a trichloroacetimidate donor; increased stereoselectivity, presumably arising from the intramolecular formation of a transient intermediate thiophenium ion, correlates with increased bulk of the glycosyl acceptor.
Stereoselective direct glycosylation with anomeric hydroxy sugars by activation with phthalic anhydride and trifluoromethanesulfonic anhydride involving glycosyl phthalate intermediates
Kwan, Soo Kim,Fulse, Dinanath Baburao,Ju, Yuel Baek,Lee, Bo-Young,Heung, Bae Jeon
supporting information; experimental part, p. 8537 - 8547 (2009/02/02)
An efficient direct one-pot glycosylation method with anomeric hydroxy sugars as glycosyl donors employing phthalic anhydride and triflic anhydride as activating agents has been developed. Thus, highly stereoselective β-mannopyranosylations were achieved
