65451-12-9Relevant articles and documents
Prebiotic selection and assembly of proteinogenic amino acids and natural nucleotides from complex mixtures
Islam, Saidul,Bu?ar, Dejan-Kre?imir,Powner, Matthew W.
, p. 584 - 589 (2017/05/31)
A central problem for the prebiotic synthesis of biological amino acids and nucleotides is to avoid the concomitant synthesis of undesired or irrelevant by-products. Additionally, multistep pathways require mechanisms that enable the sequential addition of reactants and purification of intermediates that are consistent with reasonable geochemical scenarios. Here, we show that 2-aminothiazole reacts selectively with two- and three-carbon sugars (glycolaldehyde and glyceraldehyde, respectively), which results in their accumulation and purification as stable crystalline aminals. This permits ribonucleotide synthesis, even from complex sugar mixtures. Remarkably, aminal formation also overcomes the thermodynamically favoured isomerization of glyceraldehyde into dihydroxyacetone because only the aminal of glyceraldehyde separates from the equilibrating mixture. Finally, we show that aminal formation provides a novel pathway to amino acids that avoids the synthesis of the non-proteinogenic α,α-disubstituted analogues. The common physicochemical mechanism that controls the proteinogenic amino acid and ribonucleotide assembly from prebiotic mixtures suggests that these essential classes of metabolite had a unified chemical origin.
Process for the preparation of enantiomerically enriched compounds
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Page/Page column 4-5, (2010/11/29)
1. Process for the preparation of enantiomerically enriched amino aldehydes and amino alcohols, wherein a corresponding enantiomerically enriched amino nitrile is subjected to hydrogenation in the presence of hydrogen, a hydrogenation catalyst, preferably a Pd-catalyst and a mineral acid. For the preparation of an amino aldehyde hydrogen preferably is present at a hydrogen-pressure between 0.1 and 2 MPa, in particular between 0.5 and 1 MPa. The amino aldehyde preferably is isolated in the form of a chemically and configurationally stable derivative. For the preparation of an amino alcohol, preferably at least during part of the hydrogenation hydrogen is present at a hydrogen-pressure between 2 and 10 MPa, in particular between 4 and 6 MPa. In a preferred embodiment the hydrogen-pressure initially is between 0,5 and 2 MPa and subsequently, after most of the nitrile starting material is converted, the hydrogen pressure is increased to a value between 2 and 10 MPa. The enantiomerically enriched nitrile starting material may a.o. be prepared by enzymatic resolution, classical resolution, resolution via preferential crystallization, diastereomeric synthesis, catalytic asymmetric synthesis or dehydratation of amino acid amides.
Useful Synthesis of α-Aminonitriles by Means of Alumina and Ultrasound
Hanafusa, Terukiyo,Ichihara, Junko,Ashida, Tetsuya
, p. 687 - 690 (2007/10/02)
Combined use of alumina and ultrasound facilitates the synthesis of α-aminonitriles under solid-liquid two phase conditions from carbonyl compounds, salts of amines and potassium cyanide in organic solvents.
