583-50-6Relevant articles and documents
Phillips,Criddle
, p. 3404,3405, 3407, 3408 (1960)
Combined effect of promoter and surfactant on the chromium(VI) oxidation of D-ribose in aqueous media at room temperature
Sar, Pintu,Ghosh, Aniruddha,Malik, Susanta,Saha, Bidyut
, p. 86 - 105 (2016)
Effect of polypyridine derivatives on chromium(VI) oxidation of D-ribose in aqueous media was studied spectrophotometrically. The oxidized product D-erythrose was detected by paper chromatography. The promoters 1,10-phenanthroline, 2,2-bipyridine, 2-picolinic acid, and 2,3-dipicolinic acid accelerated the oxidation, whereas isomeric 4,7-phenanthroline, 4,4-bipyridine, 4-picolinic acid, and 2,6-dipicolinic acid did not influence the oxidation. Formation of Cr(VI)-promoter complex was identified through fluorescence spectroscopy. Rate constants depended on promoter concentration. SDS and TX-100 enhanced the D-ribose oxidation, while CPC retarded the reaction. Location of D-ribose inside micelles was observed through 1H NMR. DLS study showed that the relative size of SDS and TX-100 micelles expanded in presence of chromium(VI).
PHOTOOXIDATION OF MONOSACCHARIDES WITH METAL CATALYSIS. OXIDATION WITH ATMOSPHERIC OXYGEN BY COUPLING WITH THE OXIDATION-REDUCTION CYCLE OF METAL IONS
Araki, Koji,Shiraishi, Shinsaku
, p. 267 - 270 (1984)
D-Fructose was oxidatively degraded to D-erythrose by atmospheric oxygen with irradiation of a Pyrex-filtered light in the presence of catalytic amount of FeCl3 at near neutral pH range.The reaction proceeded by coupling with the oxidation-reduction cycle of iron ion.D-Glucose-FeCl3 and D-fructose-MnCl2 systems were also found to be susceptible to the catalytic photooxidation.
Synthesis, structure, and conformation of anti-tumor agents in the solid and solution states: Hydroxyl derivatives of ftorafur
Stokes, David M.,Paul, Brajeswar,Alderfer, James L.,Wollman, Robert M.,Srikrishnan, Thamarapu
, p. 863 - 882 (2002)
The pyrimidine antimetabolite Ftorafur [FT; 5-fluoro-1-(tetrahydro-2-furyl)uracil] has shown significant antitumor activity in several adenocarcinomas with a spectrum of activity similar to, but less toxic than, 5-fluorouracil (5-FU). It is considered as a prodrug that acts as a depot form of 5-FU, and hence the two drugs exhibit a similar spectrum ofchemotherapeutic activity. Ftorafur is metabolized in animals and humans when hydroxyl groups are introduced into the tetrahydrofuran moiety. These metabolites are also thought to be as active as ftorafur but less toxic than 5-FU. Hydroxyl derivatives: 2′-hydroxyftorafur (III), 3′-hydroxyftorafur (IV) and 2′,3′-dihydroxyftorafur (II) were synthesized and X-ray and NMR studies of these hydroxyl derivatives were undertaken in our laboratories to study the structural and conformational features of Ftorafur and its metabolites in the solid and solution states. X-ray crystallographic investigations were carried out with data collected on a CAD-4 diffractometer. The structures were solved and refined using the SDP crystallographic package of Enraf-Nonius on PDP 11/34 and Microvax computers. All of the compounds studied had the base in the anti conformation. The glycosidic torsion angles varied from -20 to 60 degrees. There is an inverse correlation between the glycosyl bond distances and the χ angle. Molecules with a lower χ angle have a larger bond distance and vice versa. The sugar rings show a wide variation of conformations ranging from C2′-endo through C3′-endo to C4′-exo. The crystal structures are stabilized by hydrogen bonds involving the base nitrogen atom N3 and the hydroxyl oxygen atoms of the sugar rings as donors and the keto oxygens O2 and O4 of the base and the hydroxyl oxygen atoms O2′ and O3′ as acceptors. The NMR studies were carried out on Brueker 400 and 600MHz instruments. Simulated proton spectra were obtained through Laocoon, and pseudorotational parameters were solved by Pseurot. Presence of syn or anti forms was demonstrated with the use of NOE experiments. The glycosyl conformations in solution vary more widely than in the solid state. The conformations of the sugar molecules are in agreement with the values obtained in the solid state. The studies of the structure and conformation in the solid and solution states give a model for the Ftorafur molecule that could be used in structure, function and biological activity correlation studies.
Selective Reductive Dimerization of CO2into Glycolaldehyde
Zhang, Dan,Jarava-Barrera, Carlos,Bontemps, Sébastien
, p. 4568 - 4575 (2021/05/04)
The selective dimerization of CO2 into glycolaldehyde is achieved in a one-pot two-step process via formaldehyde as a key intermediate. The first step concerns the iron-catalyzed selective reduction of CO2 into formaldehyde via formation and controlled hydrolysis of a bis(boryl)acetal compound. The second step concerns the carbene-catalyzed C-C bond formation to afford glycolaldehyde. Both carbon atoms of glycolaldehyde arise from CO2 as proven by the labeling experiment with 13CO2. This hybrid organometallic/organic catalytic system employs mild conditions (1 atm of CO2, 25 to 80 °C in less than 3 h) and low catalytic loadings (1 and 2.5%, respectively). Glycolaldehyde is obtained in 53% overall yield. The appealing reactivity of glycolaldehyde is exemplified (i) in a dimerization process leading to C4 aldose compounds and (ii) in a tri-component Petasis-Borono-Mannich reaction generating C-N and C-C bonds in one process.
Glucose oxidation to formic acid and methyl formate in perfect selectivity
Albert, Jakob,Bukowski, Anna,Kumpidet, Chiraphat,Maerten, Stephanie,Vo?, Dorothea,Wasserscheid, Peter
, p. 4311 - 4320 (2020/07/14)
We report the highly remarkable discovery that glucose oxidation catalysed by polyoxometalates (POMs) in methanolic solution enables formation of formic acid and methyl formate in close to 100percent combined selectivity, thus with only negligible sugar oxidation to CO2. In detail, we report oxidation of a methanolic glucose solution using H8[PV5Mo7O40] (HPA-5) as catalyst at 90 °C and 20 bar O2 pressure. Experiments with 13C-labelled glucose confirm unambiguously that glucose is the only source of the observed formic acid and methyl formate formation under the applied oxidation conditions. Our results demonstrate a very astonishing solvent effect for the POM-catalysed glucose oxidation. In comparison to earlier work, a step-change in product yield and selectivity is achieved by applying an alcoholic reaction medium. The extremely high combined yields of formic acid and methyl formate greatly facilitate product isolation as low-boiling methyl formate (bp = 32 °C) can simply be isolated from the reaction mixture by distillation.