A series of optically active copolymers with various feed ratios have been synthesized through helix-sense-selective copolymerization catalyzed by[Rh(norbornadiene)Cl]2-triethylamine.This process involves two proline-...A series of optically active copolymers with various feed ratios have been synthesized through helix-sense-selective copolymerization catalyzed by[Rh(norbornadiene)Cl]2-triethylamine.This process involves two proline-derived acetylene monomers,(S)-N-(4-chlorophenyl)carbamoyl-2-ethynyl pyrrolidine(MCl)and(S)-N-(tert-butoxycarbonyl)-2-ethynyl pyrrolidine,followed by acidic deprotection and neutralization.These copolymers adopt helical conformations with a preferred handedness,as demonstrated by nuclear magnetic resonance spectroscopy and a series of spectroscopic analyses.The chiroptical activity intensity of copolymer has been found to increase with MCl content.Consequently,the enantioseparation capabilities of copolymers containing 95 mol%,90 mol%,and 85 mol%MCl units have been assessed as chiral stationary phases in high-performance liquid chromatography because of their good chiroptical activities.These chiral stationary phases effectively enantioseparate racemic alcohols,sulfoxides,amides,and metal complexes.Notably,the copolymer with 90 mol%MCl shows superior chiral recognition ability,especially for 1-(2,4-dichlorophenyl)-2-(1H-imidazol-1-yl)ethanol(α=1.19)and 4-methylbenzenesulfinamide(α=1.47).Insights from molecular dynamic simulation and autodock analysis indicate that hydrogen bonding andπ-πstacking interactions between the chiral stationary phases and enantiomers play a key role for successful chiral separation.Our contribution not only demonstrates the importance of hydrogen bonding donor and copolymer chiroptical activity of chiral stationary phases for chiral resolution,but will also provide valuable insights for the future development of novel stationary phases.展开更多
Ordered porous silica nanospheres with pores vertical to the walls were prepared by using 1,3,5-trimethyl-benzen(TMB)and hexadecitrile trimethyl ammonium bromide(CTAB)as templates.After removing the templates,porous s...Ordered porous silica nanospheres with pores vertical to the walls were prepared by using 1,3,5-trimethyl-benzen(TMB)and hexadecitrile trimethyl ammonium bromide(CTAB)as templates.After removing the templates,porous structures were obtained.The porous silica nanosperes were further modified with amino and amino acid functionalization to obtain L-Glutamic acid-functionalized mesoporous silica nanospheres,which were used as chiral selective agents for amino acid enantioseparation such as PheCOOH,PhgCOOH,and TrpCOOH enantiomers.The experimental results show that the functionalized nanospheres have good adsorption selectivity for D-PheCOOH and L-PhgCOOH,especially showing high adsorption selectivity for the L-TrpCOOH enantiomers compared with L-PheCOOH and D-PhgCOOH and D-TrpCOOH enantiomers.展开更多
Aim To establish a HPLC method for the separation of the enantiomers of zolmitriptan. Methods The separations were performed on Chiralcel OJ column with hexane-ethanol-diethylamine（85：15：0.2） as mobile phase at a ...Aim To establish a HPLC method for the separation of the enantiomers of zolmitriptan. Methods The separations were performed on Chiralcel OJ column with hexane-ethanol-diethylamine（85：15：0.2） as mobile phase at a flow rate of 0.8 mL·min^-1 and detecttion wavelength of 227 nm at 35 ℃. Several related parameters for separation were studied. Results Baseline separation （Rs 〉 1.5） was easily obtained in the case, and the R-isomer impurity in zolmitriptan was determined. Conclusion The method developed in this study has been successfully applied for quality-control purposes.展开更多
With high performance capillary electrophoresis using -cyclodextrin or its deriveatives as the chiral selectors, five pairs of drug enantiomers were separated, The PH of the back- gmund electrolyte and the chiral sele...With high performance capillary electrophoresis using -cyclodextrin or its deriveatives as the chiral selectors, five pairs of drug enantiomers were separated, The PH of the back- gmund electrolyte and the chiral selector concentrations were optimized; and the effect of organic modifier on separation of chlorpheniramine enantiomers was also inver展开更多
Enantioseparation of aminoglutethimide was performed by high-speed counter-current chromatography with a two-phase system composed of ethyl acetate： methanol： water = 10： 1： 9. The lower phase contained 20 mmol/L ...Enantioseparation of aminoglutethimide was performed by high-speed counter-current chromatography with a two-phase system composed of ethyl acetate： methanol： water = 10： 1： 9. The lower phase contained 20 mmol/L of carboxymethly-β-cyclodextrin as chiral selector. The enantiomers were separated in 1.2 h and identified by chiral HPLC. This method was very efficient for the chiral preparative separation.展开更多
Chiral metal-organic frameworks(CMOFs)with enantiomeric subunits have been employed in chiral chemistry.In this study,a CMOF formed from 6-methoxyl-(8S,9R)-cinchonan-9-ol-3-carboxylic acid(HQA)and ZnCl_(2),{(HQA)(ZnCl...Chiral metal-organic frameworks(CMOFs)with enantiomeric subunits have been employed in chiral chemistry.In this study,a CMOF formed from 6-methoxyl-(8S,9R)-cinchonan-9-ol-3-carboxylic acid(HQA)and ZnCl_(2),{(HQA)(ZnCl_(2))(2.5H_(2)O)}n,was constructed as a chiral stationary phase(CSP)via an in situ fabrication approach and used for chiral amino acid and drug analyses for the first time.The{(HQA)(ZnCl_(2))(2.5H_(2)O)}n nanocrystal and the corresponding chiral stationary phase were systematically characterised using a series of analytical techniques including scanning electron microscopy,X-ray diffraction,Fourier transform infrared spectroscopy,circular dichroism,X-ray photoelectron spectroscopy,thermogravimetric analysis,and Brunauer-Emmett-Teller surface area measurements.In opentubular capillary electrochromatography(CEC),the novel chiral column exhibited strong and broad enantioselectivity toward a variety of chiral analytes,including 19 racemic dansyl amino acids and several model chiral drugs(both acidic and basic).The chiral CEC conditions were optimised,and the enantioseparation mechanisms are discussed.This study not only introduces a new high-efficiency member of the MOF-type CSP family but also demonstrates the potential of improving the enantioselectivities of traditional chiral recognition reagents by fully using the inherent characteristics of porous organic frameworks.展开更多
Enantioseparation of threeβ-blockers,i.e.,atenolol,metoprolol and propranolol,was studied on amylose tris(3-chloro-5-methylphenylcarbamate)immobilized chiral stationary phase using supercritical fluid chromatography(...Enantioseparation of threeβ-blockers,i.e.,atenolol,metoprolol and propranolol,was studied on amylose tris(3-chloro-5-methylphenylcarbamate)immobilized chiral stationary phase using supercritical fluid chromatography(SFC).The effect of organic modifiers(methanol,isopropanol and their mixture),column temperature and back pressure on chiral separation ofβ-blockers was evaluated.Optimum chromatographic separation with respect to resolution,retention,and analysis time was achieved using a mixture of CO_(2) and 0.1%isopropyl amine in isopropanol:methanol(50:50,V/V),in 75:25(V/V)ratio.Under the optimized conditions,the resolution factors(Rs)and separation factors(a)were greater than3.0 and 1.5,respectively.Further,with increase in temperature(25-45℃)and pressure(100-150 bars)there was corresponding decrease in retention factors(k),a and Rs.However,a reverse trend(a and Rs)was observed for atenolol with increase in temperature.The thermodynamic data from van’t Hoff plots revealed that the enantioseparation was enthalpy driven for metoprolol and propranolol while entropy driven for atenolol.To understand the mechanism of chiral recognition and the elution behavior of the enantiomers,molecular docking studies were performed.The binding energies obtained from simulation studies were in good agreement with the elution order found experimentally and also with the free energy values.The method was validated in the concentration range of 0.5-10μg/m L for all the enantiomers.The limit of detection and limit of quantitation ranged from 0.126 to 0.137μg/m L and 0.376-0.414μg/m L,respectively.The method was used successfully to analyze these drugs in pharmaceutical preparations.展开更多
In this wo rk,the phase-transitioned BSA(PTB)film using the mild and fast fabrication process adhered to the capillary inner wall uniformly,and the fabricated PTB film-coated capillary column was applied to realize op...In this wo rk,the phase-transitioned BSA(PTB)film using the mild and fast fabrication process adhered to the capillary inner wall uniformly,and the fabricated PTB film-coated capillary column was applied to realize open tubular capillary electrochromatography(OT-CEC)enantioseparation.The enantioseparation ability of PTB film-coated capillary was evaluated with eight pairs of chiral analytes including drugs and neurotransmitters,all achieving good resolution and symmetrical peak shape.For three consecutive runs,the relative standard deviations(RSD)of migration time for intra-day,inter-day,and column-tocolumn repeatability were in the range of 0.3%-3.5%,0.2%-4.9%and 2.1%-7.7%,respectively.Moreover,the PTB film-coated capillary column ran continuously over 300 times with high separation efficiency.Therefore,the coating method based on BSA self-assembly supramolecular film can be extended to the preparation of other proteinaceous capillary columns.展开更多
The enantioseparation of dencichine and its D-isomer was achieved on a novel chiral stationary phase via coating N-（2-hydroxyl-3-octoxyl） propyl-S-benzyl-（L）-cysteine on YWG-C18 phase by ligand exchange chromatogr...The enantioseparation of dencichine and its D-isomer was achieved on a novel chiral stationary phase via coating N-（2-hydroxyl-3-octoxyl） propyl-S-benzyl-（L）-cysteine on YWG-C18 phase by ligand exchange chromatography.展开更多
The influence of different alcohol modifiers in mobile phase on the chiral separation of 4-methoxyl flavanone, 5-methoxyl flavanone and 6-methoxyl flavanone on cellulose tris (3, 5-dimethylphenylcarbamate) (CDMPC) col...The influence of different alcohol modifiers in mobile phase on the chiral separation of 4-methoxyl flavanone, 5-methoxyl flavanone and 6-methoxyl flavanone on cellulose tris (3, 5-dimethylphenylcarbamate) (CDMPC) column was studied and the chiral recognition mechanism was discussed. Using hexane-tert-butanol (1.31 mol L-1) as the mobile phase, those three methoxyl flavanones were excellently separated on CDMPC chiral column.展开更多
This paper reported the enantioseparation of Naproxen, Ketoprofen and Etodolac on tartardiamide-DMB chiral stationary phase (CHI-DMB) and (R,R) –DNB-DPEDA chiral stationary phase,using hexane as the mobile phase with...This paper reported the enantioseparation of Naproxen, Ketoprofen and Etodolac on tartardiamide-DMB chiral stationary phase (CHI-DMB) and (R,R) –DNB-DPEDA chiral stationary phase,using hexane as the mobile phase with various modifiers. The influence of the mobile phase composition including the type and concentration of the modifiers in hexane and the structures of the analytes on the chiral separation was studied. The results indicated that the steric structure of the solute, especially the environment of the chiral carbon, was the predominant factor for the chiral recognition. The type, the steric structure and the concentration of the modifiers also influence the retention factor and the resolution. The chiral recognition mechanism of the analytes on CHI-DMB and (R,R) –DNB-DPEDA was also discussed. The hydrogen-bonding interaction played an important role on enantioseparation on CHI-DMB, so did the π-π interaction. On (R,R) –DNB-DPEDA the π-π interaction was the key for the solutes retention and enantioseparation, while hydrogen-bonding interaction was not important. Additionally, it has been demonstrated that enantioselectivity and retention was also dependent upon the nature and functional groups on the aromatic ring of solutes and CSP.展开更多
Chiral extractant plays a key role in chiral extraction,and considerable efforts have been undertaken for the development of new and efficient chiral extractants in recent years.This work demonstrated for the first ti...Chiral extractant plays a key role in chiral extraction,and considerable efforts have been undertaken for the development of new and efficient chiral extractants in recent years.This work demonstrated for the first time that chiral ferrocenyl diphosphine ligand(Mandyphos-Pd)had considerable ability to enantioseparate 3-Chlorophenylglycine enantiomers with separation factor(α)of 2.64.Mandyphos-Pd concentration and pH had significant influences on enantioselectivity,while operating temperature showed less influence.The extraction experiments can be performed at room temperature(20℃)which had the advantage of energy saving.After optimization,the highest performance factor(pf,0.08376)was obtained at the condition of pH 7.8 and Mandyphos-Pd concentration 1.2 mmol·L^(-1).According to the experimental results,the possible recognition mechanism was discussed.展开更多
In this work, a series of chiral phenethylamine synergistic tricarboxylic acid modified β-cyclodextrin bonded stationary phase for high performance liquid chromatography(HPLC) were synthesized via a simple one-pot sy...In this work, a series of chiral phenethylamine synergistic tricarboxylic acid modified β-cyclodextrin bonded stationary phase for high performance liquid chromatography(HPLC) were synthesized via a simple one-pot synthesis approach. Various racemates(aryl alcohols, flavanones, triazoles, benzoin, etc.) were well separated on the tricarboxylic acid modified chiral stationary phases in both normal and reversed modes with good reproducibility and stability, and the influence of mobile phase composition on resolution(R_(s)) were deeply investigated. The RSD values of Rsfor repeatability and column-to-column were below 1.28% and 3.05%, respectively. Hence, the fabrication of tricarboxylic acid modified chiral stationary phase(CSPs) is a new efficient strategy to improve the application of β-cyclodextrin as CSPs in the field of chromatography.展开更多
Researchers engrossed in enantioseparation keep seeking for versatile chiral separation selectors.This work proposes a concept of quasi-dual-chiral-channel(QDCC)enantioseparation platform,where the surface sequentiall...Researchers engrossed in enantioseparation keep seeking for versatile chiral separation selectors.This work proposes a concept of quasi-dual-chiral-channel(QDCC)enantioseparation platform,where the surface sequentially grafted quinine(QN)and functional cyclodextrin(CD)can imitate two independent chiral channels without mutual interference to achieve wide spectrum chiral resolution.Chiral separation results combined with molecular docking simulation indicates that the different interaction mode of QN and functional CD layer renders QDCC the wide separation capability.This work provides a valuable insight into the rational design of versatile enantioseparation materials.展开更多
Seven chiral compounds were resolved on cellulose tris (3,5-dimethylphenylcarbamate) chiral stationary phase (CDMPC-CSP) using n-hexane/alcohol as mobile phase. Solvent strength and structural characteristics of the c...Seven chiral compounds were resolved on cellulose tris (3,5-dimethylphenylcarbamate) chiral stationary phase (CDMPC-CSP) using n-hexane/alcohol as mobile phase. Solvent strength and structural characteristics of the compounds effecting on the retention and resolution were discussed. Satisfactory separation was obtained.展开更多
Several kinds of racemic naproxen ester were successfully separated on CTMB chiral stationary phase with hexane-ethanol (98:2, vol./vol.) as the mobile phase. The influence of mobile phase composition and structure o...Several kinds of racemic naproxen ester were successfully separated on CTMB chiral stationary phase with hexane-ethanol (98:2, vol./vol.) as the mobile phase. The influence of mobile phase composition and structure of racemic naproxen ester on chiral separation was studied and the chiral recognition mechanism of CTMB was discussed.展开更多
Two chiral selectors were synthesized from tartaric acid. The selectors were simultaneously immobilized on 3-aminopropyl silica gel to obtain a new biselector chiral stationary phase （CSP） in order to determine the ...Two chiral selectors were synthesized from tartaric acid. The selectors were simultaneously immobilized on 3-aminopropyl silica gel to obtain a new biselector chiral stationary phase （CSP） in order to determine the influence of selector structure of biselector CSPs on the chiral recognition capability. For comparison, the single-selector CSP was also prepared. The biselector CSP shows an improved overall chiral recognition capability in comparison with the single-selector CSP. During the enantioseparation, temporary diastereoisomers are likely formed by complexation between a chiral analyte and the two selectors on the biselector CSP. The functional groups in the two selectors are complementary in electronic effect and/or in steric hindrance for the chiral recognition.展开更多
Enantioseparation of salbutamol solute was carried out in liquid-supported membrane by using a polyvinylidene fluoride hollow-fiber module. The enantioselective transport of solute was facilitated by combinatorial chi...Enantioseparation of salbutamol solute was carried out in liquid-supported membrane by using a polyvinylidene fluoride hollow-fiber module. The enantioselective transport of solute was facilitated by combinatorial chiral selectors, which were dissolved in toluene organic solvent. The effects of molar concentration ratios of salbutamol to combinatorial chiral selectors, and the pH value of buffer solution on enantioseparation were investigated. The results show that when the molar concentration ratio is 2∶1∶1, the maximum separation factor and enantiomer excess are 1.49 and 19.74%, respectively, and the R-enantiomer flux is more than S-enantiomer; the pH value of buffer solution influences the performances of enantioseparartion obviously, and the appropriate range of pH value is 7.07.2.展开更多
Biomacromolecules including protein and nucleic acids are considered as promising chiral selectors in the fields of enantioselective separation, owing to their inherent chirality, polymorphous structures, stable physi...Biomacromolecules including protein and nucleic acids are considered as promising chiral selectors in the fields of enantioselective separation, owing to their inherent chirality, polymorphous structures, stable physicochemical properties, good biocompatibility as well as susceptible modification and regulation. In this review, firstly,enantioselective recognition mechanism of proteins and nucleic acids toward different enantiomers is discussed,as well as their potential applications on the chiral separation of racemic compounds. Secondly, preparative enantioseparation adopting biomolecule-modified hybrid materials including porous microspheres, magnetic nanoparticles and affinity membranes, are introduced respectively. Finally, novel chiroptical materials constructed on the basis of chiral induction, transfer, amplification and transcription, are recognized as promising candidates in future applications.展开更多
Membranes offer an attractive route to efficient enantioseparation,especially compared with energy-intensive techniques like chromatography.However,tuning membrane structure and porosity to separate chiral molecules r...Membranes offer an attractive route to efficient enantioseparation,especially compared with energy-intensive techniques like chromatography.However,tuning membrane structure and porosity to separate chiral molecules remains challenging.Here,we present a process for producing intrinsically chiral,ordered discrete metallacycycle 1 membranes on polyacrylonitrile supports through interfacial coordination-driven self-assembly using organic precursor 2 and metallic precursor 3.These chiral membranes,with their orientated architecture,exhibit ultra-high enantioselectivity(up to 100%)and permeation efficiency for racemic 1-phenylethanol,1-phenylethylamine,and 2-phenylglycinol.Thermodynamic data and molecular simulations revealed the retarded transport mechanism of the membrane,resulting in highly efficient enantioseparation.Notably,when integrated into a circuit-controlled 3D-printed module,the aligned metallacyclic membrane retained its enantioselectivity for high-value pharmaceutical racemic salbutamol.This approach provides a feasible strategy for creating supramolecular metallacyclic channels in chiral membranes,demonstrating the potential for accurate enantioseparations.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52273002 and 52333008)the funding of Boya Postdoctoral Fellowship at Peking University,BMS Junior Fellow Program and the National Funding Program for Postdoctoral Researchers(No.GZC20230031).
文摘A series of optically active copolymers with various feed ratios have been synthesized through helix-sense-selective copolymerization catalyzed by[Rh(norbornadiene)Cl]2-triethylamine.This process involves two proline-derived acetylene monomers,(S)-N-(4-chlorophenyl)carbamoyl-2-ethynyl pyrrolidine(MCl)and(S)-N-(tert-butoxycarbonyl)-2-ethynyl pyrrolidine,followed by acidic deprotection and neutralization.These copolymers adopt helical conformations with a preferred handedness,as demonstrated by nuclear magnetic resonance spectroscopy and a series of spectroscopic analyses.The chiroptical activity intensity of copolymer has been found to increase with MCl content.Consequently,the enantioseparation capabilities of copolymers containing 95 mol%,90 mol%,and 85 mol%MCl units have been assessed as chiral stationary phases in high-performance liquid chromatography because of their good chiroptical activities.These chiral stationary phases effectively enantioseparate racemic alcohols,sulfoxides,amides,and metal complexes.Notably,the copolymer with 90 mol%MCl shows superior chiral recognition ability,especially for 1-(2,4-dichlorophenyl)-2-(1H-imidazol-1-yl)ethanol(α=1.19)and 4-methylbenzenesulfinamide(α=1.47).Insights from molecular dynamic simulation and autodock analysis indicate that hydrogen bonding andπ-πstacking interactions between the chiral stationary phases and enantiomers play a key role for successful chiral separation.Our contribution not only demonstrates the importance of hydrogen bonding donor and copolymer chiroptical activity of chiral stationary phases for chiral resolution,but will also provide valuable insights for the future development of novel stationary phases.
基金Funded by the Opening Funding of the Provincial and Ministerial Joint Construction of the State Key Laboratory of New Textile Materials and Advanced Processing Technology(No.FZ2020003)the Science and Technology Innovation Program of Wuhan Textile University(No.233060)。
文摘Ordered porous silica nanospheres with pores vertical to the walls were prepared by using 1,3,5-trimethyl-benzen(TMB)and hexadecitrile trimethyl ammonium bromide(CTAB)as templates.After removing the templates,porous structures were obtained.The porous silica nanosperes were further modified with amino and amino acid functionalization to obtain L-Glutamic acid-functionalized mesoporous silica nanospheres,which were used as chiral selective agents for amino acid enantioseparation such as PheCOOH,PhgCOOH,and TrpCOOH enantiomers.The experimental results show that the functionalized nanospheres have good adsorption selectivity for D-PheCOOH and L-PhgCOOH,especially showing high adsorption selectivity for the L-TrpCOOH enantiomers compared with L-PheCOOH and D-PhgCOOH and D-TrpCOOH enantiomers.
文摘Aim To establish a HPLC method for the separation of the enantiomers of zolmitriptan. Methods The separations were performed on Chiralcel OJ column with hexane-ethanol-diethylamine（85：15：0.2） as mobile phase at a flow rate of 0.8 mL·min^-1 and detecttion wavelength of 227 nm at 35 ℃. Several related parameters for separation were studied. Results Baseline separation （Rs 〉 1.5） was easily obtained in the case, and the R-isomer impurity in zolmitriptan was determined. Conclusion The method developed in this study has been successfully applied for quality-control purposes.
文摘With high performance capillary electrophoresis using -cyclodextrin or its deriveatives as the chiral selectors, five pairs of drug enantiomers were separated, The PH of the back- gmund electrolyte and the chiral selector concentrations were optimized; and the effect of organic modifier on separation of chlorpheniramine enantiomers was also inver
基金The work is supported by National Natural Science Foundation of China （No. 30160092） TRAP0YT and Yunnan Province＇s Natural Science Foundation.
文摘Enantioseparation of aminoglutethimide was performed by high-speed counter-current chromatography with a two-phase system composed of ethyl acetate： methanol： water = 10： 1： 9. The lower phase contained 20 mmol/L of carboxymethly-β-cyclodextrin as chiral selector. The enantiomers were separated in 1.2 h and identified by chiral HPLC. This method was very efficient for the chiral preparative separation.
基金This study was funded by the National Natural Science Foundation of China(Grant No.:82003705)the Shanghai Science and Technology Innovation Foundation(Grant Nos.:23010500200 and 23ZR1422700).
文摘Chiral metal-organic frameworks(CMOFs)with enantiomeric subunits have been employed in chiral chemistry.In this study,a CMOF formed from 6-methoxyl-(8S,9R)-cinchonan-9-ol-3-carboxylic acid(HQA)and ZnCl_(2),{(HQA)(ZnCl_(2))(2.5H_(2)O)}n,was constructed as a chiral stationary phase(CSP)via an in situ fabrication approach and used for chiral amino acid and drug analyses for the first time.The{(HQA)(ZnCl_(2))(2.5H_(2)O)}n nanocrystal and the corresponding chiral stationary phase were systematically characterised using a series of analytical techniques including scanning electron microscopy,X-ray diffraction,Fourier transform infrared spectroscopy,circular dichroism,X-ray photoelectron spectroscopy,thermogravimetric analysis,and Brunauer-Emmett-Teller surface area measurements.In opentubular capillary electrochromatography(CEC),the novel chiral column exhibited strong and broad enantioselectivity toward a variety of chiral analytes,including 19 racemic dansyl amino acids and several model chiral drugs(both acidic and basic).The chiral CEC conditions were optimised,and the enantioseparation mechanisms are discussed.This study not only introduces a new high-efficiency member of the MOF-type CSP family but also demonstrates the potential of improving the enantioselectivities of traditional chiral recognition reagents by fully using the inherent characteristics of porous organic frameworks.
基金Department of Chemistry,Gujarat University,for supporting this workHuman Resource Development GroupCouncil of Scientific&Industrial Research(CSIR),New Delhi,for Research Associate Fellowship(File No.:09/070(0058)2K18 EMR-I)。
文摘Enantioseparation of threeβ-blockers,i.e.,atenolol,metoprolol and propranolol,was studied on amylose tris(3-chloro-5-methylphenylcarbamate)immobilized chiral stationary phase using supercritical fluid chromatography(SFC).The effect of organic modifiers(methanol,isopropanol and their mixture),column temperature and back pressure on chiral separation ofβ-blockers was evaluated.Optimum chromatographic separation with respect to resolution,retention,and analysis time was achieved using a mixture of CO_(2) and 0.1%isopropyl amine in isopropanol:methanol(50:50,V/V),in 75:25(V/V)ratio.Under the optimized conditions,the resolution factors(Rs)and separation factors(a)were greater than3.0 and 1.5,respectively.Further,with increase in temperature(25-45℃)and pressure(100-150 bars)there was corresponding decrease in retention factors(k),a and Rs.However,a reverse trend(a and Rs)was observed for atenolol with increase in temperature.The thermodynamic data from van’t Hoff plots revealed that the enantioseparation was enthalpy driven for metoprolol and propranolol while entropy driven for atenolol.To understand the mechanism of chiral recognition and the elution behavior of the enantiomers,molecular docking studies were performed.The binding energies obtained from simulation studies were in good agreement with the elution order found experimentally and also with the free energy values.The method was validated in the concentration range of 0.5-10μg/m L for all the enantiomers.The limit of detection and limit of quantitation ranged from 0.126 to 0.137μg/m L and 0.376-0.414μg/m L,respectively.The method was used successfully to analyze these drugs in pharmaceutical preparations.
基金the financial support from the National Natural Science Foundation of China(No.21874060)the Special Funding for Open and Shared Large-Scale Instruments and Equipments of Lanzhou University(No.LZU-GXJJ-2019C038)。
文摘In this wo rk,the phase-transitioned BSA(PTB)film using the mild and fast fabrication process adhered to the capillary inner wall uniformly,and the fabricated PTB film-coated capillary column was applied to realize open tubular capillary electrochromatography(OT-CEC)enantioseparation.The enantioseparation ability of PTB film-coated capillary was evaluated with eight pairs of chiral analytes including drugs and neurotransmitters,all achieving good resolution and symmetrical peak shape.For three consecutive runs,the relative standard deviations(RSD)of migration time for intra-day,inter-day,and column-tocolumn repeatability were in the range of 0.3%-3.5%,0.2%-4.9%and 2.1%-7.7%,respectively.Moreover,the PTB film-coated capillary column ran continuously over 300 times with high separation efficiency.Therefore,the coating method based on BSA self-assembly supramolecular film can be extended to the preparation of other proteinaceous capillary columns.
文摘The enantioseparation of dencichine and its D-isomer was achieved on a novel chiral stationary phase via coating N-（2-hydroxyl-3-octoxyl） propyl-S-benzyl-（L）-cysteine on YWG-C18 phase by ligand exchange chromatography.
文摘The influence of different alcohol modifiers in mobile phase on the chiral separation of 4-methoxyl flavanone, 5-methoxyl flavanone and 6-methoxyl flavanone on cellulose tris (3, 5-dimethylphenylcarbamate) (CDMPC) column was studied and the chiral recognition mechanism was discussed. Using hexane-tert-butanol (1.31 mol L-1) as the mobile phase, those three methoxyl flavanones were excellently separated on CDMPC chiral column.
文摘This paper reported the enantioseparation of Naproxen, Ketoprofen and Etodolac on tartardiamide-DMB chiral stationary phase (CHI-DMB) and (R,R) –DNB-DPEDA chiral stationary phase,using hexane as the mobile phase with various modifiers. The influence of the mobile phase composition including the type and concentration of the modifiers in hexane and the structures of the analytes on the chiral separation was studied. The results indicated that the steric structure of the solute, especially the environment of the chiral carbon, was the predominant factor for the chiral recognition. The type, the steric structure and the concentration of the modifiers also influence the retention factor and the resolution. The chiral recognition mechanism of the analytes on CHI-DMB and (R,R) –DNB-DPEDA was also discussed. The hydrogen-bonding interaction played an important role on enantioseparation on CHI-DMB, so did the π-π interaction. On (R,R) –DNB-DPEDA the π-π interaction was the key for the solutes retention and enantioseparation, while hydrogen-bonding interaction was not important. Additionally, it has been demonstrated that enantioselectivity and retention was also dependent upon the nature and functional groups on the aromatic ring of solutes and CSP.
基金This work was financially supported by National Natural Science Foundation of China(Grant No.51703060)Hunan Provincial Innovation Foundation for Postgraduate(Grant No.CX2018B673).
文摘Chiral extractant plays a key role in chiral extraction,and considerable efforts have been undertaken for the development of new and efficient chiral extractants in recent years.This work demonstrated for the first time that chiral ferrocenyl diphosphine ligand(Mandyphos-Pd)had considerable ability to enantioseparate 3-Chlorophenylglycine enantiomers with separation factor(α)of 2.64.Mandyphos-Pd concentration and pH had significant influences on enantioselectivity,while operating temperature showed less influence.The extraction experiments can be performed at room temperature(20℃)which had the advantage of energy saving.After optimization,the highest performance factor(pf,0.08376)was obtained at the condition of pH 7.8 and Mandyphos-Pd concentration 1.2 mmol·L^(-1).According to the experimental results,the possible recognition mechanism was discussed.
基金supported by the National Natural Science Foundation of China(Nos.22074154 and 22174129)Nature Science Foundation of Zhejiang Province(No.LZY21E030001)+1 种基金Foundation for Science and Tech Research Project of Gansu Province(Nos.20JR10RA052 and 20JR10RA292)LICP Cooperation Foundation for Young Scholars(No.HZJJ20-08)。
文摘In this work, a series of chiral phenethylamine synergistic tricarboxylic acid modified β-cyclodextrin bonded stationary phase for high performance liquid chromatography(HPLC) were synthesized via a simple one-pot synthesis approach. Various racemates(aryl alcohols, flavanones, triazoles, benzoin, etc.) were well separated on the tricarboxylic acid modified chiral stationary phases in both normal and reversed modes with good reproducibility and stability, and the influence of mobile phase composition on resolution(R_(s)) were deeply investigated. The RSD values of Rsfor repeatability and column-to-column were below 1.28% and 3.05%, respectively. Hence, the fabrication of tricarboxylic acid modified chiral stationary phase(CSPs) is a new efficient strategy to improve the application of β-cyclodextrin as CSPs in the field of chromatography.
基金financially funded by the National Key R&D Program of China(No.2019YFC1905500)National Natural Science Foundation of China(No.21922409)National Natural Science Foundation of China(No.22274109).
文摘Researchers engrossed in enantioseparation keep seeking for versatile chiral separation selectors.This work proposes a concept of quasi-dual-chiral-channel(QDCC)enantioseparation platform,where the surface sequentially grafted quinine(QN)and functional cyclodextrin(CD)can imitate two independent chiral channels without mutual interference to achieve wide spectrum chiral resolution.Chiral separation results combined with molecular docking simulation indicates that the different interaction mode of QN and functional CD layer renders QDCC the wide separation capability.This work provides a valuable insight into the rational design of versatile enantioseparation materials.
文摘Seven chiral compounds were resolved on cellulose tris (3,5-dimethylphenylcarbamate) chiral stationary phase (CDMPC-CSP) using n-hexane/alcohol as mobile phase. Solvent strength and structural characteristics of the compounds effecting on the retention and resolution were discussed. Satisfactory separation was obtained.
文摘Several kinds of racemic naproxen ester were successfully separated on CTMB chiral stationary phase with hexane-ethanol (98:2, vol./vol.) as the mobile phase. The influence of mobile phase composition and structure of racemic naproxen ester on chiral separation was studied and the chiral recognition mechanism of CTMB was discussed.
基金Supported by the National Natural Science Foundation of China (20675061 and 50973086)the Research Project of Department of Education of Hubei Province (Z20081501)
文摘Two chiral selectors were synthesized from tartaric acid. The selectors were simultaneously immobilized on 3-aminopropyl silica gel to obtain a new biselector chiral stationary phase （CSP） in order to determine the influence of selector structure of biselector CSPs on the chiral recognition capability. For comparison, the single-selector CSP was also prepared. The biselector CSP shows an improved overall chiral recognition capability in comparison with the single-selector CSP. During the enantioseparation, temporary diastereoisomers are likely formed by complexation between a chiral analyte and the two selectors on the biselector CSP. The functional groups in the two selectors are complementary in electronic effect and/or in steric hindrance for the chiral recognition.
文摘Enantioseparation of salbutamol solute was carried out in liquid-supported membrane by using a polyvinylidene fluoride hollow-fiber module. The enantioselective transport of solute was facilitated by combinatorial chiral selectors, which were dissolved in toluene organic solvent. The effects of molar concentration ratios of salbutamol to combinatorial chiral selectors, and the pH value of buffer solution on enantioseparation were investigated. The results show that when the molar concentration ratio is 2∶1∶1, the maximum separation factor and enantiomer excess are 1.49 and 19.74%, respectively, and the R-enantiomer flux is more than S-enantiomer; the pH value of buffer solution influences the performances of enantioseparartion obviously, and the appropriate range of pH value is 7.07.2.
基金Supported by the National Natural Science Foundation of China(21206107)the National High-tech R&D Program of China(2012AA03A609)Program for Changjiang Scholars and Innovative Research Team in University(IRT1161)
文摘Biomacromolecules including protein and nucleic acids are considered as promising chiral selectors in the fields of enantioselective separation, owing to their inherent chirality, polymorphous structures, stable physicochemical properties, good biocompatibility as well as susceptible modification and regulation. In this review, firstly,enantioselective recognition mechanism of proteins and nucleic acids toward different enantiomers is discussed,as well as their potential applications on the chiral separation of racemic compounds. Secondly, preparative enantioseparation adopting biomolecule-modified hybrid materials including porous microspheres, magnetic nanoparticles and affinity membranes, are introduced respectively. Finally, novel chiroptical materials constructed on the basis of chiral induction, transfer, amplification and transcription, are recognized as promising candidates in future applications.
基金gratefully acknowledge the research funding provided by National Natural Science Foundation of China(22473086)the Distinguished Natural Scientific Foundation of Tianjin(24JCJQJC00100)+1 种基金the Hebei Natural Science Foundation(B2024110030)the Natural Scientific Foundation of Tianjin(22JCYBJC01130).
文摘Membranes offer an attractive route to efficient enantioseparation,especially compared with energy-intensive techniques like chromatography.However,tuning membrane structure and porosity to separate chiral molecules remains challenging.Here,we present a process for producing intrinsically chiral,ordered discrete metallacycycle 1 membranes on polyacrylonitrile supports through interfacial coordination-driven self-assembly using organic precursor 2 and metallic precursor 3.These chiral membranes,with their orientated architecture,exhibit ultra-high enantioselectivity(up to 100%)and permeation efficiency for racemic 1-phenylethanol,1-phenylethylamine,and 2-phenylglycinol.Thermodynamic data and molecular simulations revealed the retarded transport mechanism of the membrane,resulting in highly efficient enantioseparation.Notably,when integrated into a circuit-controlled 3D-printed module,the aligned metallacyclic membrane retained its enantioselectivity for high-value pharmaceutical racemic salbutamol.This approach provides a feasible strategy for creating supramolecular metallacyclic channels in chiral membranes,demonstrating the potential for accurate enantioseparations.
