Solid-phase catalytic reactions of tritium with carbohydrates: 3. Mechanism of isomerization of epimeric pentoses in the course of solid-phase catalytic hydrogenation with tritium

Methoden der C‐H‐Funktionalisierung für den Wasserstoffisotopenaustausch

“…Using the HSCIE reaction, it becomes possible to substitute hydrogen for deuterium or tritium almost quantitatively in a series of amino acids without racemization. [ 52 ] This method has also been applied in the tritiation of GABA and L-DOPA, [53] brassinolide, [54] ataluren (PTC124), [ 55 ] druglike glutamate and dopamine ligands, [56] maraviroc, a new generation agent for HIV treatment blocking chemokine receptors CCR-5, [57] D-ribose, [58] serotonin (5-methoxytryptamine), and diazepam (see, for example, 32-36, Scheme 15). [59] Scheme 15.…”

Radiochemistry

“…The various solid-state reactions 52 that can be used to make tritium labelled organic compounds have been reviewed as have routes 53 to tritium labelled dopamines. For the most part tritium labelling can be achieved by standard organic procedures such as the use of [ 3 H]methyl iodide (dinucleotides), 54 catalytic reduction with [ 3 H]hydrogen (carbohydrates), 55,56 or the use of tritiated reducing agents such as lithium tritide (dimethylditritiogermane), 57 sodium [ 3 H]borohydride (puerarin 58 -an isoflavine C-glycoside and PR-104, 59 a hypoxia-activated pre-prodrug) or lithium [ 3 H]aluminohydride (phosphoramide 60 derivatives). Other more specific methods such as catalytic dehalogenation have been used to prepare a phenyl derivative of phenserine tartrate, 61 whilst the simpler more general procedure of isotope exchange (usually using tritiated water) has been used to label SCH-211803 62 (Pt catalyst) and a series of isotopomers of tyramine.…”