73045-58-6Relevant academic research and scientific papers
Towards stable di-carba analogues of guanofosfocins
Duchek, Jan,Huang, Mu-Hua,Vasella, Andrea
supporting information; scheme or table, p. 2940 - 2942 (2011/06/23)
Guanofosfocins are strong inhibitors of chitin synthases, but also very prone to hydrolytic cleavage. Two advanced intermediates 15 and 20 for the synthesis of stable di-carba-guanofosfocins were prepared via ester 11. Acylation of the allylic C-glycoside
An easy and versatile approach for the regioselective De-O-benzylation of protected sugars based on the I2/Et3SiH combined system
Pastore, Antonello,Valerio, Silvia,Adinolfi, Matteo,Iadonisi, Alfonso
experimental part, p. 5881 - 5889 (2011/06/24)
The use of cheap and easy to handle reagents, such as I2 and Et3SiH, at low temperature allows the regioselective removal of benzyl protecting groups from highly O-benzylated carbohydrates. The observed regioselectivity is dependent
One-pot catalytic glycosidation/Fmoc removal - An iterable sequence for straightforward assembly of oligosaccharides related to HIV gp120
Pastore, Antonello,Adinolfi, Matteo,Iadonisi, Alfonso,Valerio, Silvia
experimental part, p. 711 - 718 (2010/03/24)
The removal of a transient Fmoc protecting group can be simply performed by the addition of excess Et3N just after the accomplishment of a Bi(OTf)3-promoted glycosidation reaction. The obtained oligosaccharide can be directly employed as a glycosyl acceptor for further elongation of the saccharide. The preparation of biologically important, linear and branched mannans incorporated into HIV gp 120 demonstrates that the iteration of this one-pot sequence leads to a very straightforward oligosaccharide assembly.
Facile oxidative cleavage of 4-O-benzyl ethers with dichlorodicyanoquinone in rhamno- and mannopyranosides
Crich, David,Vinogradova, Olga
, p. 3581 - 3584 (2008/02/04)
On exposure to dichlorodicyanoquinone in wet dichloromethane at room temperature, equatorial 4-O-benzyl ethers are removed with moderate selectivity in the presence of other benzyl ethers in glycopyranosides and glycothiopyranosides.
Preparation of an advanced intermediate for the synthesis of stable analogues of guanofosfocin
George, Tesmol G.,Szolcsanyi, Peter,Koenig, Stefan G.,Paterson, Duncan E.,Isshiki, Yoshiaki,Vasella, Andrea
, p. 1287 - 1298 (2007/10/03)
The synthesis of C-mannosyl-guanosine 23, an advanced intermediate for the preparation of stable analogues of guanofosfocin, is described. This convergent approach features an improved Traube-type synthesis of a 8-substituted guanine, followed by ribosylation. NMR Studies show that the C-mannopyranosyl moiety of 23 adopts a distorted 1C4 conformation while the nucleoside is predominantly syn-oriented.
Diisobutylaluminium hydride (DIBAL-H) as a molecular scalpel: A new mechanistic proposal for a spiroketal rearrangement
Meng, Xiangbao,Zhang, Yongmin,Sollogoub, Matthieu,Sina?, Pierre
, p. 8165 - 8168 (2007/10/03)
Taking advantage of our knowledge of the capacity of DIBAL-H to de-O-alkylate, we propose an alternative mechanism for a spiroketal rearrangement described by E. Suàrez. We also show that this proposal can account for the formation of the secondary product, whose original structure we propose to correct.
Highly diastereoselective 1,4-addition of an organocuprate to methyl α-D-gluco-, α-D-manno-, or α-D-galactopyranosides tethering an α,β-unsaturated ester. Novel asymmetric access to β-C-substituted butanoic acids
Totani,Nagatsuka,Yamaguchi,Takao,Ohba,Tadano
, p. 5965 - 5975 (2007/10/03)
The 1,4-addition of magnesium divinylcuprate prepared from vinylmagnesium bromide and cuprous bromide to some 4-O-crotonyl derivatives of methyl α-D-glucopyranoside proceeds with a high level of diastereochemical induction, providing the adduct in good-to
Synthesis of a pentasaccharide corresponding to the repeating unit of the exopolysaccharide from Cryptococcus neoformans serovar D
Zegelaar-Jaarsveld, Korien,Smits, Sander A. W.,Van Der Marel, Gijs A.,Van Boom, Jacques H.
, p. 1819 - 1832 (2007/10/03)
The assembly of the pentasaccharide repeating unit of the exopolysaccharide from Cryptococcus neoformans serovar D (i.e. 1) is described. The glucuronic acid residue in 1 is introduced as a glucopyranoside and oxidized in a later stage of the synthesis. Thus, iodonium ion-assisted glycosylation of the partially protected methyl mannopyranoside 11 with ethylthio donor 14 gave, after selective deprotection, disaccharide 18. Elongation of the latter with D-glucopyranoside 35 gave trisaccharide 36. Subsequent protective group manipulations yielded the acceptor 37. Condensation of disaccharide donor 31 with trisaccharide acceptor 37 yielded pentasaccharide 38. Protective group manipulations of 38 afforded 42, the glucoside of which was oxidized to yield the corresponding glucuronide 44. Hydrogenolysis of 44 gave the target pentasaccharide 1.
