87470-72-2Relevant academic research and scientific papers
Synthesis and reactivity of 4'-deoxypentenosyl disaccharides
Padungros, Panuwat,Fan, Ren-Hua,Casselman, Matthew D.,Cheng, Gang,Khatri, Hari R.,Wei, Alexander
, p. 4878 - 4891 (2014/06/23)
4-Deoxypentenosides (4-DPs) are versatile synthons for rare or higher-order pyranosides, and they provide an entry for structural diversification at the C5 position. Previous studies have shown that 4-DPs undergo stereocontrolled DMDO oxidation; subsequent epoxide ring-openings with various nucleophiles can proceed with both anti or syn selectivity. Here, we report the synthesis of α- and β-linked 4'-deoxypentenosyl (4'-DP) disaccharides, and we investigate their post-glycosylational C5' additions using the DMDO oxidation/ring-opening sequence. The α-linked 4'-DP disaccharides were synthesized by coupling thiophenyl 4-DP donors with glycosyl acceptors using BSP/Tf2O activation, whereas β-linked 4'-DP disaccharides were generated by the decarboxylative elimination of glucuronyl disaccharides under microwave conditions. Both α- and β-linked 4'-DP disaccharides could be epoxidized with high stereoselectivity using DMDO. In some cases, the α-epoxypentenosides could be successfully converted into terminal l-iduronic acids via the syn addition of 2-furylzinc bromide. These studies support a novel approach to oligosaccharide synthesis, in which the stereochemical configuration of the terminal 4'-DP unit is established at a post-glycosylative stage.
Nickel(II) chloride-mediated regioselective benzylation and benzoylation of diequatorial vicinal diols
Gangadharmath, Umesh B.,Demchenko, Alexei V.
, p. 2191 - 2193 (2007/10/03)
Ni(II)-chelates of monosaccharide vicinal diols were found to be useful intermediates in regioselective monobenzylation and monobenzoylation. It was observed that the substitution occurs exclusively at the position adjacent to the axially oriented substit
Chemistry of 4,6-O-benzylidene-D-glycopyranosyl triflates: Contrasting behavior between the gluco and manno series
Crich, David,Cai, Weiling
, p. 4926 - 4930 (2007/10/03)
Activation of either anomer of S-phenyl 2,3-di-O-benzyl-4,6-O- benzylidene-1-deoxy-1-thia-D-glucopyranoside with triflic anhydride in dichloromethane at -78 °C in the presence of 2,6-di-tert-butyl-4- methylpyridine affords a highly active glycosylating species which, on addition of alcohols, provides α-glucosides with high selectivity. This selectivity stands in stark contrast to the analogous mannopyranoside series, which affords the β-mannosides with excellent selectivity under the same conditions. Low-temperature NMR experiments support the notion that a glucosyl triflate is formed in the initial activation step. Possible reasons for the diverging stereoselectivity in the gluco and manno series are discussed.
Practical synthesis of oligosaccharides. Partial synthesis of avermectin B(1a)
Nicolaou,Dolle,Papahatjis,Randall,Dolle
, p. 4189 - 4192 (2007/10/02)
A practical synthesis of oligosaccharides from phenylthio sugars via glycosyl fluorides is described. The new technology is applied to the synthesis of hexasaccharide 9 from a glucose derivative and avermectin B1a(11) from an avermectin B1
HYDROGENOLYSIS OF THE BENZYLIDENE ACETALS OF THIOGLYCOSIDES WITH THE LiAlH4-AlCl3 REAGENT. SYNTHESIS OF PARTIALLY BENZYLATED THIOGLYCOSIDE DERIVATIVES
Liptak, A.,Jodal, I.,Harangi, J.,Nanasi, P.
, p. 415 - 422 (2007/10/02)
Reductive hydrogenolysis of phenyl 2,3-di-O-benzyl-4,6-O-benzylidene-1-thio-β-D-gluco- (4) and -galactopyranoside (8) and phenyl 2,3,6,2',3'-penta-O-benzyl-4',6'-O-benzylidene-1-thio-β-cellobioside (15) with the LiAlH4-AlCl3 reagent resulted in the corres
