7006-35-1Relevant academic research and scientific papers
Preparation and characterization of a new open-tubular capillary column for enantioseparation by capillary electrochromatography
Li, Yingjie,Tang, Yimin,Qin, Shili,Li, Xue,Dai, Qiang,Gao, Lidi
, p. 283 - 292 (2019/02/05)
In order to use the enantioseparation capability of cationic cyclodextrin and to combine the advantages of capillary electrochromatography (CEC) with open-tubular (OT) column, in this study, a new OT-CEC, coated with cationic cyclodextrin (1-allylimidazolium-β-cyclodextrin [AI-β-CD]) as chiral stationary phase (CSP), was prepared and applied for enantioseparation. Synthesized AI-β-CD was characterized by infrared (IR) spectrometry and mass spectrometry (MS). The preparation conditions for the AI-β-CD-coated column were optimized with the orthogonal experiment design L9(34). The column prepared was characterized by scanning electron microscopy (SEM) and elemental analysis (EA). The results showed that the thickness of stationary phase in the inner surface of the AI-β-CD-coated columns was about 0.2 to 0.5?μm. The AI-β-CD content in stationary phase based on the EA was approximately 2.77?mmol·m?2. The AI-β-CD-coated columns could separate all 14 chiral compounds (histidine, lysine, arginine, glutamate, aspartic acid, cysteine, serine, valine, isoleucine, phenylalanine, salbutamol, atenolol, ibuprofen, and napropamide) successfully in the study and exhibit excellent reproducibility and stability. We propose that the column, coated with AI-β-CD, has a great potential for enantioseparation in OT-CEC.
Chromatographic Resolution of α-Amino Acids by (R)-(3,3'-Halogen Substituted-1,1'-binaphthyl)-20-crown-6 Stationary Phase in HPLC
Wu, Peng,Wu, Yuping,Zhang, Junhui,Lu, Zhenyu,Zhang, Mei,Chen, Xuexian,Yuan, Liming
supporting information, p. 1037 - 1042 (2017/07/25)
Three new chiral stationary phases (CSPs) for high-performance liquid chromatography were prepared from R-(3,3'-halogen substituted-1,1'-binaphthyl)-20-crown-6 (halogen = Cl, Br and I). The experimental results showed that R-(3,3'-dibromo-1,1'-binaphthyl)-20-crown-6 (CSP-1) possesses more prominent enantioselectivity than the two other halogen-substituted crown ether derivatives. All twenty-one α-amino acids have different degrees of separation on R-(3,3'-dibromo-1,1'-binaphthyl)-20-crown-6-based CSP-1 at room temperature. The enantioselectivity of CSP-1 is also better than those of some commercial R-(1,1'-binaphthyl)-20-crown-6 derivatives. Both the separation factors (α) and the resolution (Rs) are better than those of commercial crown ether-based CSPs [CROWNPAK CR(+) from Daicel] under the same conditions for asparagine, threonine, proline, arginine, serine, histidine and valine, which cannot be separated by commercial CR(+). This study proves the commercial usefulness of the R-(3,3'-dibromo-1,1'-binaphthyl)-20-crown-6 chiral stationary phase.
Chiral separation of underivatized amino acids by reactive extraction with palladium-BINAP complexes
Verkuijl, Bastiaan J. V.,Minnaard, Adriaan J.,De Vries, Johannes G.,Feringa, Ben L.
experimental part, p. 6526 - 6533 (2010/03/01)
(Figure Presented) In answer to the need for a more economic technology for the separation of racemates, a novel system for reactive enantioselective liquid-liquid extraction (ELLE) is introduced. Palladium (S)-BINAP complexes are employed as hosts in the separation of underivatized amino acids. The system shows the highest selectivity for the ELLE of tryptophan with metal complexes as hosts reported to date and shows a good selectivity toward a range of natural and unnatural amino acids. Furthermore, the host can be prepared in situ from commerically available compounds. Bulk-membrane transport in the form of U-tube experiments demonstrates the enantioselective and catalytic nature of the transport. The dependency of the system on parameters such as pH, organic solvent, and host-substrate ratio has been established. 31P NMR spectroscopy has been used to confirm the preferred enantiomer in the extraction experiments. The intrinsic selectivity was deduced by determination of the association constants of the palladium complex with the tryptophan enantiomers.
Optimal Conditions for the Enzymatic Production of D-Amino Acids from the Corresponding 5-Substituted Hydantoins
Yokozeki, Kenzo,Nakamori, Shigeru,Yamanaka, Shigeru,Eguchi, Chikahiko,Mitsugi, Koji,Yoshinaga, Fumihiro
, p. 715 - 720 (2007/10/02)
The reaction conditions for the production of D-p-hydroxyphenylglycine (D-HPG) from DL-5-(p-hydroxyphenyl)hydantoin (DL-HPH) by cells of Pseudomonas sp.AJ-11220 and the cultural conditions for this bacterium for the formation of the D-HPG-producing enzyme involved by this bacterium were investigated.The optimal pH of this reaction was about 8.0 and the optimal temperature about 43 deg C.The D-HPG producing enzyme was inducibly produced in Pseudomonas sp.AJ-11220 in proportion to the cell growth.Cells containing high activity were obtained when Pseudomonas sp.AJ-11220 was grown in a medium containing 20 g of glucose 5 g of (NH4)2SO4, 1g of KH2PO4, 3 g of K2HPO4, 0.5 g of MgSO4.7H2O, 0.01 g of FeSO4.7H2O, 0.01 g of MnSO4.4H2O, 10 g of yeast extract 5 g of DL-5-cyanoethylhydantoin and 20 g of CaCO3 in a total volume of 1 liter (pH 7.0).Under the optimal conditions, 25 mg/ml of D-HPG was asymmetrically and directly produced from 30 mg/ml of DL-HPH with a molar yield of 92percent.Various D-amino acids could also be effectively produced from the corresponding 5-substituted hydantoins.
