4358-64-9Relevant articles and documents
Silicate complexes of sugars in aqueous solution
Lambert, Joseph B.,Lu, Gang,Singer, Stephanie R.,Kolb, Vera M.
, p. 9611 - 9625 (2004)
Certain sugars react readily with basic silicic acid to form soluble 2/1 (sugar/silicic acid) silicate complexes. Failure of monohydroxy compounds to give soluble products under these conditions indicates that the sugar silicates are chelates: five-membered diolato rings. Only furanose forms react. Pyranose sugars are stable under these conditions. Because all glycosides fail to react with silicic acid under these conditions, reaction appears to involve the anomeric position (C1 in aldoses, C2 in ketoses), which has a more acidic hydroxy group. Reaction is completed only when the anomeric hydroxy group is cis to an adjacent hydroxy group. The appropriate furanose form must have sufficient natural abundance and solubility to provide an observable product, as measured by 29Si and 13C NMR spectroscopy. These structural and practical constraints rationalize the successful reaction of the monosaccharides ribose, xylose, lyxose, talose, psicose, fructose, sorbose, and tagatose and the disaccharides lactulose, maltulose, and palatinose. Glucose, mannose, galactose, and sucrose, among others, failed to form complexes. This high selectivity for formation of sugar silicates may have ramifications in prebiotic chemistry.
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Otey,Mehltretter
, p. 1673 (1961)
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Hydrido-bis(meso-oxolanylen-3,4-dioxy)-λ5-phosphane
Betz, Richard,Kluefers, Peter
, p. 1615 - 1629 (2008)
The symmetric hydrido-spiro-λ5-phosphane derived from anhydroerythritol (meso-oxolane-3,4-diol, AnEryt), HP(AnErytH- 2)2(3), was prepared by two different synthetic protocols. One route involves a three step synthesis starting from phosphorus trichloride via 2-chloro-tetrahydro-furo[3,4- d][1,3,2]dioxaphosphole (1) and diethyl-(tetrahydro-furo[3,4-d][1,3,2] dioxaphosphol-2-yl)-amine (2) as intermediates. The first intermediate, P(AnErytH- 2)Cl (1), was isolated as a crystalline solid and its structure was determined by single crystal X-ray diffraction. 1 is the first example of a halogeno substituted phosphane derived from an aliphatic diol whose molecular structure in the solid state was determined by X-ray diffraction studies. Alternatively, the title compound can also be obtained in a one-pot procedure starting from tris(N,N-dimethylamino)phosphane. All new compounds were characterized by their physical constants (melting point, refractory index), NMR, IR, Raman, UV/VIS, mass spectrometry, as well as elemental analysis. Some spectroscopic proofs for the spiro nature of the title compound are given. Copyright Taylor & Francis Group, LLC.
METHODS AND COMPOSITIONS FOR BIORENEWABLE POLYESTERS DERIVED FROM CAMPHORIC ACID
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Paragraph 0180, (2020/08/28)
In one aspect, the disclosure relates to biorenewable polyesters and polyester copolymers derived from camphoric acid, methods of making same, and articles comprising same. The disclosed biorenewable polyesters can have a Mn of from about 5,000 Da to about 500,000 Da. Also disclosed herein is the preparation of various monomers useful in the reactions disclosed herein, e.g., cis-1,4-anhydroerythritol and bis(2-hydroxyethyl) camphorate. In various aspects, the disclosed biorenewable polyesters and polyester copolymers can be used to the production of various articles utilizing a conventional polyester or polyester copolymer, that is, to replace, in part or in whole, a conventional nonbiorenewable polyester or polyester copolymer. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.
Efficient synthesis of α-branched purine-based acyclic nucleosides: Scopes and limitations of the method
Dra?ínsky, Martin,Frydrych, Jan,Janeba, Zlatko,Slavětínská, Lenka Po?tová
, (2020/10/02)
An efficient route to acylated acyclic nucleosides containing a branched hemiaminal ether moiety is reported via three-component alkylation of N-heterocycle (purine nucleobase) with acetal (cyclic or acyclic, variously branched) and anhydride (preferentially acetic anhydride). The procedure employs cheap and easily available acetals, acetic anhydride, and trimethylsilyl trifluoromethanesulfonate (TMSOTf). The multi-component reaction is carried out in acetonitrile at room temperature for 15 min and provides moderate to high yields (up to 88%) of diverse acyclonucleosides branched at the aliphatic side chain. The procedure exhibits a broad substrate scope of N-heterocycles and acetals, and, in the case of purine derivatives, also excellent regioselectivity, giving almost exclusively N-9 isomers.