Chirality high-performance liquid

Nikolai LN, McClure EL, MacLeod SL, Wong CS (2006) Stereoisomer quantification of the Beta-blocker drugs atenolol, metoprolol, and propranolol in wastewaters by chiral high-performance liquid chromatography-tandem mass spectrometry. J Chromatogr A 1131 103-109... 

Breithaupt, D. E., P. Weller et al. (2004). Comparison of plasma responses in human subjects after the ingestion of 3R.3R -xeaxanthin dipalmitate from wolfberry (Lycium barbarum) and non-esterified 3R,3R -zeaxanthin using chiral high-performance liquid chromatography. Br. J. Nutr. 91(5) 707-713. 

Chu, Y.Q., Wainer, I.W. (1988). The measurement of warfarin enantiomers in serum using coupled achiral/chiral high performance liquid chromatography. Pharm. Res. 5, 680-683. 

Clark, B.J., Hamdi, A., Berrisford, R.G., Sahanathan, S., Meams, AJ. (1991). Reversed-phase and chiral high-performance liquid chromatographic assay of hupivacaine and its enantiomers in clinical samples after continuous extraplural infusion. J. Chromatogr. 553,383-390. 

Ferretti, R., Gallinella, B., La, T.F., Zanitti, L. (1988). Direct resolution of a new antifungal agent, voriconazole(UK-109,496) and its potential impurities, by use of coupled achiral-chiral high-performance liquid chromatography. Chromatographia 47, 649-654. 

Kim, K.H., Kim, H.J., Hong, S.-R, Shin, S.D. (2000a). Determination of tertbutaline enantiomers in human plasma by coupled achiral-chiral high performance liquid chromatography. Arch. Pharm. Res. 23, 441-445. 

Oda, Y., Asajawa, N., Yoshida, Y., Sato, T. (1992). Online determination and resolution for the enantiomers of ketoprofen in plasma using coupled achiral-chiral high-performance liquid chromatography. J. Pharm. Biomed. Anal. 10, 81-87. 

Because of the instability of cyanohydrins, the characterization of cyanohydrins mostly should be hydroxyl protected. In 2001, Gerrits et al. [26] investigated the influence of solvent composition on the stability of unprotected cyanohydrins and then described a method to analyze unprotected cyanohydrins (with regard to enantiomeric purity and conversion) via chiral high-performance liquid chromatography (HPLC). Hernandez et al. [27] and the groups... 

Enantiomers of the 8,9-dichloro-2,3,4,4 ,5,6-hexahydro-177-pyrazino[l,2-tf]quinoxalin-5-one (structure 249 Rz = R3 = Cl R1 = R4 = H) could be separated by normal-phase, chiral high-performance liquid chromatography (HPLC) with increased retention and separation factors if ethoxynonafluorobutane was used as solvent, instead of -hexane <2001JCH(918)293>. 

The above chemistry has been applied to the synthesis of a series of derivatives which show activity against animal parasites. In order to confirm further the stmcture and configuration of the most active enantiomer of one of these compounds, the enantiomers were separated by chiral high-performance liquid chromatography (HPLC), and single crystal X-ray diffraction of a 2 1 CuCl2 complex was carried out <2005BML2375>. 

The product was analysed by gas chromatography (GC), dissolved in hexane/propan-2-ol (70/30) and analysed by chiral high-performance liquid chromatography (HPLC)... 

Assay of the reaction mixture. A 50 /iL sample was removed from the reaction and the dichloromethane component was evaporated under nitrogen for 20 s. The sample was then resuspended in 600 /iL isopropanol and assayed by chiral high-performance liquid chromatography. A 250 mm x 4.6 mm Chiralpak AD-H column was used with an eluant of 85 15 heptane/ethanol, a flow rate of 3 mL min a temperature of 10 °C, a detection wavelength of 245 nm and a sample injection volume of 2 fL. 

Amino acid formation was monitored over 24 h by chiral high-performance liquid chromatography (CHIROBIOTIC T column) with samples diluted 10-fold (in H2O) to a suitable concentration. 

Separations of enantiomers can be achieved by chiral chromatography. Even, when the enantioselective synthesis of drugs and pharmaceuticals is possible, a major part of chiral compounds is still produced as a racemate and needs to be separated into the enantiomers by chiral high performance liquid chromatography. 

F. Gimenez, R. Farinotti, A. Thuillier, G. Hazebroucq and I. W. Wainer, Determination of the enantiomers of mefloquine in plasma and whole blood using a coupled achiral-chiral high-performance liquid chromatographic system , J. Chromatogr. 529 339-346(1990). 

Tambute, A., Gareil, R, Caude, M., and Rosset, R., Preparative separation of racemic tertiary phosphine oxides by chiral high-performance liquid chromatography, J. Chromatogr., 363, 81, 1986. 

The enantiomeric purity of the sulfamidates 55a and 55b was established using Whelk 0-2 chiral high-performance liquid chromatography (HPLC) <2005TA1583>, and in each case chiral HPLC confirmed an enantiomeric excess of at least 97%. These two sulfamidate oils proved to be very stable when stored for up to a year at — 20 °C. 

In an earlier study <1984JA6087>, the product of photosenzitized oxygenation with 9,10-d icy a noanthracene (DCA) of 1- and 2-naphthyl cis- and //war-substituted epoxides could be proved by X-ray crystallography to be the cA-trioxolane 27, which is a meso form. The corresponding /razw-trioxolane was obtained by the ozonation of cis-1,2-bis(2-naphthyl)ethene and it could be resolved into enantiomers 28 and 29 on a chiral high-performance liquid chromatography (FIPLC) stationary phase (Scheme 2). 

W. H. Pirkle, D. W. House, and J. E. Finn, Broad spectrum resolution of optical isomers using chiral high-performance liquid chromatographic bonded phase, J. Chromatogr., 792 143 (1980). 

Although structural elucidation of lignans is not a difficult task, the similarities between the structures can create problems. In particular, the determination of stereochemistry at the chiral center requires NOE/ NOESY NMR experiments and/or X-ray analyses. The enantiomeric excesses of the known lignans (+)-lariciresinol, (-)-secoisolariciresinol and (+)-taxiresinol, isolated from Japanese yew T. cuspidata roots, were determined by chiral high-performance liquid chromatographic analyses [78] except for (+)-pinoresinol (77% enantiomeric excess), they were found to be optically pure by Kawamura et al. In an earlier study, the presence of taxiresinol in Taxus species was reported by Mujumdar et al. [69] after they had isolated it from the heartwood of T. baccata, although they did not study its stereochemistry. 

Buser, H.-R. Miiller, M.D., Isomer-selective and enantiomerselective determination of DDT and related compounds using chiral high-resolution gas chromatography/mass spectrometry and chiral high-performance liquid chromatography Anal. Chem. 1995, 67, 2691-2698. 

Haglund, R, Enantioselective separation of polychlorinated biphenyl atropisomers using chiral high-performance liquid chromatography J. Chromatogr. A 1996, 724, 219-228. 

McKenna, C.E., et al. (2010). Synthesis, chiral high performance liquid chromatographic resolution and enantiospecific activity of a potent New geranylgeranyl transferase inhibitor, 2-hydroxy-3-imidazo[l,2-a]pyridin-3-yl-2-phosphonopropionic acid. J Med... 

The measurement of warfarin enantiomers in serum using coupled achiral/chiral high-performance liquid chromatography" (110), An assay for the serum concentrations of (fi)-warfarin and (S)-warfarin was developed using the BSA CSF coupled to a Pinkerton internal-surface reverse-phase (ISRP) achiral column. The ISRP column was used to separate (R,S)-warfarin from the serum components and warfarin metabolites and to quantitate the total warfarin concentration. The eluent containing the (A,S)-warfarin was then selectively transferred to the BSA CSR where the enantiomers were enantioselectively resolved (a = 1.19) and the enantiomeric composition determined. 

Wilson, T. D. Sample solvent effects in an apparent chiral high-performance liquid chromatographic separation on /J-cyclodextrin. Pharm. Sci. Dep., Sterling-Winthrop Res. Inst., Rensselaer, NY, J. Chromatogr. 448(l) 31-39 1988. 

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