118353-70-1Relevant academic research and scientific papers
Ion trap mass spectrometry for kinetic studies of stable isotope labeled vitamin A at low enrichments
Dueker, Stephen R.,Mercer, Roger S.,Jones, A. Daniel,Clifford, Andrew J.
, p. 1369 - 1374 (1998)
The role of β-carotene in chemoprevention of cancers and other chronic diseases generated controversy when sub-populations taking β-carotene supplements showed increased mortality in clinical trails. Determination of the dynamics of β-carotene in individual human subjects has emerged as a high priority. Stable isotope labeled β-carotene tracers can be employed to determine rates of conversion to retinol (vitamin A), but tracer doses must be small to minimize perturbation of endogenous retinoid and carotenoid pools. In such cases, ratios of labeled tracer/endogenous retinol are often low, and quantitative analysis at enrichments of 4 and unlabeled retinol, as their tert-butyldimethylsilyl ethers, at low enrichments using an ion trap mass spectrometer operated in selected ion storage mode. Electron ionization of analyte takes place in the ion trap using conditions that eject ions outside the range m/z 390-420, and molecular ions at m/z 400 and 404 from retinol and retinol-d4 are quantified. Using this approach, unlabeled retinol yields a signal close to values calculated from natural isotopic abundances (~0.13%), whereas several quadrupole instruments operated using selected ion monitoring yielded 2-5 times greater signal when no labeled retinol was present.
The simultaneous in-situ generation of aldehydes and phosphorus ylides: A convenient multi-step one-pot olefination protocol
Wang, Qian,Wei, Heng-Xu,Schlosser, Manfred
, p. 3263 - 3268 (2007/10/03)
The lithium α-(dimethylamino)alkoxides resulting from the nucleophilic addition of an organolithium reagent to N,N-dimethylformamide are basic enough to deprotonate alkyltriphenylphosphonium salts suspended in tetrahydrofuran. The aldehydes liberated by t
Synthesis of New Aromatic Retinoid Analogues by Low-Valent Titanium Induced Reductive Elimination
Solladie, Guy,Girardin, Andre,Lang, Gerard
, p. 2620 - 2628 (2007/10/02)
The low-valent titanium reductive elimination reaction, already applied to the stereospecific synthesis of vitamin A and 13-cis-retinol, was used to prepare several retinoic acid analogues in the all-trans configuration or in the 13-cis configuration.This highly stereospecific trans-diene formation allowed an improved synthesis of the title compounds without any purification of the intermediates before the final stage.
HIGHLY STEREOSELECTIVE SYNTHESIS OF VITAMIN A AND ALL-TRANS RETINOIC ACID BY LOW-VALENT TITANIUM INDUCED REDUCTIVE ELIMINATION
Solladie, Guy,Girardin, Andre
, p. 213 - 216 (2007/10/02)
Application of the low-valent Titanium induced reductive elimination gave a new and highly stereoselective approach to vitamin A and all-trans retinoic acid.
