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Chromatographic Enantiomer Separation Using 9-Amino-9-(deoxy)-epiquinine-derived Chiral Selectors: Control of Chiral Recognition via Introduction of Additional Stereogenic Centers


, : Chromatographic Enantiomer Separation Using 9-Amino-9-(deoxy)-epiquinine-derived Chiral Selectors: Control of Chiral Recognition via Introduction of Additional Stereogenic Centers. Acta Chimica Slovenica 59(3): 454-463

Three new cinchona-type chiral selectors have been prepared by attaching N-pivaloyl-glycine, N-pivaloyl-(S)-valine and N-pivaloyl-(R)-valine segments to the C9-amino function of 9-amino-9-(deoxy)-epiquinine (eAQN), and immobilized to silica to provide the corresponding chiral stationary phases (CSPs). Evaluation of the chromatographic enantioseparation characteristics of these CSPs with a broad assortment of N-carbamoyl protected amino acids under polar organic mobile phase conditions revealed modest chiral recognition capabilities for N-Fmoc-, N-Cbz- and N-Boc-derivatives. It was found that the enantioselective analyte binding to these CSPs is strictly controlled by the absolute stereo-chemistry of the amino acid functionalities attached to the C9-amino group of the eAQN framework. Specifically, the CSP derived from (S)-valine-based selector exhibits preferential binding of N-carbamoyl-(S)-amino acids, while the CSPs featuring (R)-valine- and the glycine-derived selectors show opposite enantioselective binding preference. The observed impact of analyte structure on enantioselectivity and the specific preferences in enantioselective binding point to chiral recognition mechanisms capitalizing on intermolecular ion pairing, hydrogen bonding and subtle steric interactions, with the latter making the crucial contributions to stereodiscrimination. The finding that the chiral recognition characteristics of epiquinine can be readily controlled via incorporation of additional stereogenic centers remote from the cinchona scaffold might be useful information for the design of new enantioselective receptors and organocatalysts.

US$29.90

PMID: 24061297


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Backofen, R.; Bernhart, S.H.; Flamm, C.; Fried, C.; Fritzsch, G.; Hackermüller, Jörg.; Hertel, J.; Hofacker, I.L.; Missal, K.; Mosig, A.; Prohaska, S.J.; Rose, D.; Stadler, P.F.; Tanzer, A.; Washietl, S.; Will, S., 2006: RNAs everywhere: genome-wide annotation of structured RNAs. Starting with the discovery of microRNAs and the advent of genome-wide transcriptomics, non-protein-coding transcripts have moved from a fringe topic to a central field research in molecular biology. In this contribution we review the state of the...

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Xu, Y.; Du, Y.; Cawood, P.A.; Yang, J., 2010: Provenance record of a foreland basin; detrital zircon U/Pb ages from Devonian strata in the North Qilian orogenic belt, China. Devonian strata in the North Qilian Belt of the Qilian Orogen accumulated in a foreland basin formed through collision between the North China Craton and the Central Qilian Belt. U-Pb age data for 393 detrital zircons from four sandstone samples f...

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Francken, J.C.; Slors, M., 2017: Neuroscience and everyday life: Facing the translation problem. To enable the impact of neuroscientific insights on our daily lives, careful translation of research findings is required. However, neuroscientific terminology and common-sense concepts are often hard to square. For example, when neuroscientists s...

WELSH.R.A.; STRONG.J.P.; McGILL.H.C., 1961: Colloid goiter and atherosclerosis. The thyroid glands from 453 patients 20 to 79 years of age from the New Orleans area were classified as to the presence of colloid goiter, and the coronary arteries and aortas from these same patients were independently graded for atherosclerotic...

Issel, W., 1954: Anesthesiologic progress at the otorhinolaryngological clinic of the Berlin Freie Universität after introduction of intubation anesthesia. Hno 4(8): 250-251

Norman, C., 2005: CATCH-IT report: evaluation of an Internet-based smoking cessation program: lessons learned from a pilot study. Journal of Medical Internet Research 6(4): E47; Discussion E48-E47; Discussion E48

Nriagu J.O.; Hem J.D., 1978: Chemistry of pollutant sulfur in natural waters. Pages 211-270 1978