73485-90-2Relevant articles and documents
Deuterium-induced isotope effects on the 13C chemical shifts of α- D -glucose pentaacetate
Pérez-Hernández, Nury,álvarez-Cisneros, Celina,Cerda-García-Rojas, Carlos M.,Morales-Ríos, Martha S.,Joseph-Nathan, Pedro
, p. 136 - 142 (2013)
1,2,3,4,6-Penta-O-acetyl-α-d-glucopyranose and the corresponding [1-2H], [2-2H], [3-2H], [4-2H], [5-2H], and [6,6-2H2]-labeled compounds were prepared for measuring deuterium/hydrogen-induced effects on 13C chemical shift nΔ (DHIECS) values. A conformational analysis of the nondeuterated compound was achieved using density functional theory (DFT) molecular models that allowed calculation of several structural properties as well as Boltzmann-averaged 13C NMR chemical shifts by using the gauge-including atomic orbital method. It was found that the DFT-calculated C-H bond lengths correlate with 1Δ DHIECS. Copyright
A kinetic isotope effect study on the hydrolysis reactions of methyl xylopyranosides and methyl 5-thioxylopyranosides: Oxygen versus sulfur stabilization of carbenium ions
Indurugalla,Bennet
, p. 10889 - 10898 (2007/10/03)
The following kinetic isotope effects, KIEs (klight/kheavy), have been measured for the hydrolyses of methyl α- and β-xylopyranosides, respectively, in aqueous HClO4 (μ = 1.0 M, NaClO4) at 80 °C: α-D, 1.128 ± 0.004, 1.098 ± 0.005; β-D, 1.088 ± 0.008, 1.042 ± 0.004; γ-D2, (C5) 0.986 ± 0.001, 0.967 ± 0.003; leaving-group 18O, 1.023 ± 0.002, 1.023 ± 0.003; ring 18O, 0.983 ± 0.001, 0.978 ± 0.001; anomeric 13C, 1.006 ± 0.001, 1.006 ± 0.003; and solvent, 0.434 ± 0.017, 0.446 ± 0.012. In conjunction with the reported (J. Am. Chem. Soc. 1986, 108, 7287-7294) KIEs for the acid-catalyzed hydrolysis of methyl α- and β-glucopyranosides, it is possible to conclude that at the transition state for xylopyranoside hydrolysis resonance stabilization of the developing carbenium ion by the ring oxygen atom is coupled to exocyclic C-O bond cleavage, and the corresponding methyl glucopyranosides hydrolyze via transition states in which charge delocalization lags behind aglycon departure. In the analogous hydrolysis reactions of methyl 5-thioxylopyranosides, the measured KIEs in aqueous HClO4 (μ = 1.0 M, NaClO4) at 80 °C for the α- and β-anomers were, respectively, α-D, 1.142 ± 0.010, 1.094 ± 0.002; β-D 1.061 ± 0.003, 1.0185 ± 0.001; γ-D2, (C5) 0.999 ± 0.001, 0.986 ± 0.002; leaving-group 18O, 1.027 ± 0.001, 1.035 ± 0.001; anomeric 13C, 1.031 ± 0.002, 1.028 ± 0.002; solvent, 0.423 ± 0.015, 0.380 ± 0.014. The acid-catalyzed hydrolyses of methyl 5-thio-α- and β-xylopyranosides, which occur faster than methyl α- and β-xylopyranosides by factors of 13.6 and 18.5, respectively, proceed via reversibly formed O-protonated conjugate acids that undergo slow, rate-determining exocyclic C-O bond cleavage. These hydrolysis reactions do not have a nucleophilic solvent component as a feature of the thiacarbenium ion-like transition states.
Mono-, Di-, and Tri-C-Deuteration of 1,5-Anhydro-D-glucitol
Funabashi, Masuo,Hasegawa, Toshimori
, p. 2528 - 2531 (2007/10/02)
Deuterium was effectively introduced into the title sugar (1a) at C-1, C-3, C-5, and C-6 to afford 1,5-anhydro-D-,-,-, and -glucitols respectively as primary targets for a basic study of the unknown metabolism of 1a, which had
A SIMPLE SYNTHESIS OF (1R and 1S)--1,5-ANHYDRO-D-GLUCITOL AND -1,5-ANHYDRO-D-GLUCITOL
Funabashi, Masuo,Yoshioka, Shigetake
, p. 677 - 680 (2007/10/02)
As a basic study of metabolism of 1,5-anhydro-D-glucitol, which has recently been identified in both human cerebrospinal fluid and plasma, the title compounds were conveniently synthesized as preliminary targets not only for multideuteration but for triti
