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Singh AK, Wang W, Panda DP, Bagchi D, Goud D, Ray B, He J, Peter SC. Cobalt-Induced Phase Transformation of Ni 3Ga 4 Generates Chiral Intermetallic Co 3Ni 3Ga 8. J Am Chem Soc 2023; 145:1433-1440. [PMID: 36580662 DOI: 10.1021/jacs.2c12366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The scientific community has found immense difficulty to focus on the generation of chiral intermetallics compared to the chiral molecular structure, probably due to the technical difficulty in producing them as no general controlled protocol is available. Herein, using a conventional metal flux technique, we have discovered a new ternary intermetallic Co3Ni3Ga8, substituting Co at the Ni sublattice in a highly symmetric Ni3Ga4 (Ia3̅d). Co3Ni3Ga8 crystallizes in the I4132 space group, a Sohncke type, and can host the chiral structure. To the best of our knowledge, this is the first report of a ternary intermetallic crystallizing in this space group. The chiral structure of Co3Ni3Ga8 is comprehensively mapped by various techniques such as single-crystal X-ray diffraction (XRD), synchrotron powder XRD, X-ray absorption spectroscopy (XAS), scanning transmission electron microscopy (STEM) and theoretically studied using density functional theory. The discovery of this chiral compound can inspire the researchers to design hidden ternary chiral intermetallics to study the exotic electrical and magnetic properties.
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Affiliation(s)
- Ashutosh Kumar Singh
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
| | - Wu Wang
- Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong 518055, PR China
| | - Debendra Prasad Panda
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
| | - Debabrata Bagchi
- School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
| | - Devender Goud
- School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
| | - Bitan Ray
- School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
| | - Jiaqing He
- Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong 518055, PR China
| | - Sebastian C Peter
- School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India.,New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560 064, India
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Abstract
Many structures in nature look symmetric, but this is not completely accurate, because absolute symmetry is close to death. Chirality (handedness) is one form of living asymmetry. Chirality has been extensively investigated at different levels. Many rules were coined in attempts made for many decades to have control over the selection of handedness that seems to easily occur in nature. It is certain that if good control is realized on chirality, the roads will be ultimately open towards numerous developments in pharmaceutical, technological, and industrial applications. This tutorial review presents a report on chirality from single molecules to supramolecular assemblies. The realized functions are still in their infancy and have been scarcely converted into actual applications. This review provides an overview for starters in the chirality field of research on concepts, common methodologies, and outstanding accomplishments. It starts with an introductory section on the definitions and classifications of chirality at the different levels of molecular complexity, followed by highlighting the importance of chirality in biological systems and the different means of realizing chirality and its inversion in solid and solution-based systems at molecular and supramolecular levels. Chirality-relevant important findings and (bio-)technological applications are also reported accordingly.
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3
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Liao MH, Zhang M, Hu DH, Zhang RH, Zhao Y, Liu SS, Li YX, Xiao WL, Tang E. Controlling the selectivity of an intramolecular Friedel-Crafts alkylation with alkenes using selenium under mild conditions. Org Biomol Chem 2020; 18:4034-4045. [PMID: 32191248 DOI: 10.1039/d0ob00257g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficiently divergent intramolecular Friedel-Crafts alkylation by unactivated alkenes with seleniranium ion-controlled Markovnikov/anti-Markovnikov specificities under mild conditions has been investigated. 2-Benzoxepin, isochroman, and isochromene can be produced in one-pot procedures from the same substrate in high yields and with high regio- and stereospecificity. The products are challenging to access via 7-endo-trig carbocyclizations and by 7-endo-trig carbocyclization/rearrangement/6-exo-trig oxycyclization and 6-exo-trig carbocyclization/deselenenylation reaction sequences, respectively. Mechanistic experiments indicated that in addition to the stereospecific anti-addition processes of the cyclization reactions, the formation of a stable carbocation after ring opening of the seleniranium ion leads to an NPSP-mediated 7-endo-trig carbocyclization; the steric hindrance of the seleniranium intermediate controls the regioselectivity when using TPSCA at 60 °C, which promotes 6-exo-trig carbocyclization. Two distinct catalytic cycles were proposed, and the structures of transition states and products were identified by ab initio calculations and X-ray analyses.
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Affiliation(s)
- Ming-Hong Liao
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming, 650091 China.
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4
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Ahmadabad FK, Pourayoubi M, Bakhshi H. Chiral phosphoric triamide‐based polymers for enantioseparation. J Appl Polym Sci 2019. [DOI: 10.1002/app.48034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
| | - Mehrdad Pourayoubi
- Department of Chemistry, Faculty of ScienceFerdowsi University of Mashhad Mashhad Iran
| | - Hadi Bakhshi
- Macromolecular Chemistry IIUniversity of Bayreuth Universitätsstraße 30, 95440 Bayreuth Germany
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5
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Abbate S, Longhi G, Mazzeo G, Villani C, Petković S, Ruzziconi R. CF3: an overlooked chromophore in VCD spectra. A review of recent applications in structural determination. RSC Adv 2019; 9:11781-11796. [PMID: 35517012 PMCID: PMC9063343 DOI: 10.1039/c9ra01358j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 04/03/2019] [Indexed: 12/03/2022] Open
Abstract
The VCD spectra of several chiral compounds containing the CF3 group are reviewed and analyzed. The list of compounds contains pharmaceutically relevant molecules as well as simple model molecules, having the value of case studies. In particular we point out the importance of the sign of the VCD band relative to some stretching normal mode of CF3 in the region 1110–1150 cm−1, as diagnostic of the configuration of stereogenic carbons C* to which the CF3 group is bound: the correspondence (−) ↔ (R) and (+) ↔ (S) holds for 100% of 1-aryl-2,2,2-trifluoroethanols. DFT calculations confirm these conclusions, but for the rule established here they serve just as a check. This rule is tested on two new compounds, namely N-tert-butanesulfinyl-1-(quinoline-4-yl)-2,2,2-trifluoroethylamine, 8, and 4-[2-(2,2,2-trifluoro-1-hydroxyethyl)pyrrolidin-1-yl]-2-(trifluoromethyl)benzonitrile, 10, both containing two stereogenic elements, one of them being an asymmetric carbon C* of unknown configuration binding a CF3 group. Discussion of the general validity of the rule is provided and some further tests are run on compounds in well-established drugs. VCD allows one to investigate the configuration of stereogenic centers bearing a CF3-group and to define its interactions with nearby chemical groups.![]()
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Affiliation(s)
- Sergio Abbate
- DMMT (Dipartimento di Medicina Molecolare e Traslazionale)
- Università di Brescia
- 25123 Brescia
- Italy
| | - Giovanna Longhi
- DMMT (Dipartimento di Medicina Molecolare e Traslazionale)
- Università di Brescia
- 25123 Brescia
- Italy
| | - Giuseppe Mazzeo
- DMMT (Dipartimento di Medicina Molecolare e Traslazionale)
- Università di Brescia
- 25123 Brescia
- Italy
| | - Claudio Villani
- Dipartimento di Chimica e Tecnologie del Farmaco
- Università di Roma “La Sapienza”
- 00185 Roma
- Italy
| | - Silvija Petković
- Dipartimento di Chimica, Biologia e Biotecnologie
- Università di Perugia
- 06123 Perugia
- Italy
| | - Renzo Ruzziconi
- Dipartimento di Chimica, Biologia e Biotecnologie
- Università di Perugia
- 06123 Perugia
- Italy
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6
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Rizk SA, Abdelwahab SS, Sallam HA. Regioselective Reactions, Spectroscopic Characterization, and Cytotoxic Evaluation of Spiro-pyrrolidine Thiophene. J Heterocycl Chem 2018. [DOI: 10.1002/jhet.3195] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Sameh A. Rizk
- Department of Chemistry, Faculty of Science; Ain Shams University; Cairo 11566 Egypt
| | - Salwa S. Abdelwahab
- Faculty of Pharmaceutical Sciences and Pharmaceutical Industries; Future University in Egypt; Cairo 11835 Egypt
| | - Hanan A. Sallam
- Department of Chemistry, Faculty of Science; Ain Shams University; Cairo 11566 Egypt
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7
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Calcaterra A, D’Acquarica I. The market of chiral drugs: Chiral switches versus de novo enantiomerically pure compounds. J Pharm Biomed Anal 2018; 147:323-340. [DOI: 10.1016/j.jpba.2017.07.008] [Citation(s) in RCA: 195] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 07/06/2017] [Accepted: 07/08/2017] [Indexed: 10/19/2022]
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8
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Polavarapu PL. Determination of the Absolute Configurations of Chiral Drugs Using Chiroptical Spectroscopy. Molecules 2016; 21:molecules21081056. [PMID: 27529201 PMCID: PMC6273303 DOI: 10.3390/molecules21081056] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 08/02/2016] [Accepted: 08/04/2016] [Indexed: 02/07/2023] Open
Abstract
Chiroptical spectroscopy has emerged as a promising tool for the determination of absolute configurations and predominant conformations of chiral molecules in academic laboratories. This promise has led to the adaption of chiroptical spectroscopic methods as valuable tools in chiral drug discovery research programs of the pharmaceutical industry. Most major pharmaceutical companies have invested in in-house chiroptical spectroscopy applications and reported successful outcomes. In the context of continuously increasing applications of chiroptical spectroscopy for chiral molecular structure determination, a review of recent developments and applications for chiral drugs is presented in this manuscript.
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9
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Orestes E, Bistafa C, Rivelino R, Canuto S. Including Thermal Disorder of Hydrogen Bonding to Describe the Vibrational Circular Dichroism Spectrum of Zwitterionic l-Alanine in Water. J Phys Chem A 2014; 119:5099-106. [DOI: 10.1021/jp508205k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Ednilsom Orestes
- Instituto
de Química, Universidade Federal Fluminense Campus do Valonguinho, CEP 24020-141, Niterói, RJ, Brazil
| | - Carlos Bistafa
- Instituto
de Física, Universidade de São Paulo, CP 66318, 05914-370 São Paulo, SP, Brazil
| | - Roberto Rivelino
- Instituto
de Física, Universidade de São Paulo, CP 66318, 05914-370 São Paulo, SP, Brazil
- Instituto
de Física, Universidade Federal da Bahia, 40210-340 Salvador, BA, Brazil
| | - Sylvio Canuto
- Instituto
de Física, Universidade de São Paulo, CP 66318, 05914-370 São Paulo, SP, Brazil
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10
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Lipiński PFJ, Dobrowolski JC. Local chirality measures in QSPR : IR and VCD spectroscopy. RSC Adv 2014. [DOI: 10.1039/c4ra08434a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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11
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Shen J, Yang J, Heyse W, Schweitzer H, Nagel N, Andert D, Zhu C, Morrison V, Nemeth GA, Chen TM, Zhao Z, Ayers TA, Choi YM. Enantiomeric characterization and structure elucidation of Otamixaban. J Pharm Anal 2014; 4:197-204. [PMID: 29403883 PMCID: PMC5761123 DOI: 10.1016/j.jpha.2013.10.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 10/28/2013] [Indexed: 11/15/2022] Open
Abstract
Otamixaban is a potent (Ki=0.5 nM) fXa inhibitor currently in late-stage clinical development at Sanofi for the management of acute coronary syndrome. Being unproductive in obtaining a suitable crystal of Otamixaban, the required enantiomeric characterization has been accomplished using vibrational circular dichroism (VCD) spectroscopy. Selected by a spectrum similarity index, the calculated spectra of several higher energy conformers were found to match well with the observed spectra. The characteristic IR bands of these conformers were also identified and attributed to the solvation effect. Combined with both the single crystal x-ray diffraction results for an intermediate and the proton NMR study, the absolute configuration of Otamixaban is unambiguously determined to be (R,R).
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Affiliation(s)
- Jian Shen
- Sanofi, 1041 Route 202-206, Bridgewater, NJ 08807, United States
| | - Jiping Yang
- Sanofi, 1041 Route 202-206, Bridgewater, NJ 08807, United States
| | - Winfried Heyse
- Sanofi, Industriepark Hoechst Bldg., D-65926 Frankfurt, Germany
| | | | - Norbert Nagel
- Sanofi, Industriepark Hoechst Bldg., D-65926 Frankfurt, Germany
| | - Doris Andert
- Sanofi, Industriepark Hoechst Bldg., D-65926 Frankfurt, Germany
| | - Chengyue Zhu
- Sanofi, 1041 Route 202-206, Bridgewater, NJ 08807, United States
| | - Vincent Morrison
- Sanofi, 1041 Route 202-206, Bridgewater, NJ 08807, United States
| | - Gregory A Nemeth
- Sanofi, 1041 Route 202-206, Bridgewater, NJ 08807, United States
| | - Teng-Man Chen
- Sanofi, 1041 Route 202-206, Bridgewater, NJ 08807, United States
| | - Zhicheng Zhao
- Sanofi, 1041 Route 202-206, Bridgewater, NJ 08807, United States
| | - Timothy A Ayers
- Sanofi, 1041 Route 202-206, Bridgewater, NJ 08807, United States
| | - Yong-Mi Choi
- Sanofi, 1041 Route 202-206, Bridgewater, NJ 08807, United States
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12
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Frenkel J, Wess C, Vyverman W, Pohnert G. Chiral separation of a diketopiperazine pheromone from marine diatoms using supercritical fluid chromatography. J Chromatogr B Analyt Technol Biomed Life Sci 2014; 951-952:58-61. [DOI: 10.1016/j.jchromb.2013.12.040] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 12/23/2013] [Accepted: 12/28/2013] [Indexed: 11/26/2022]
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13
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Sherer EC, Lee CH, Shpungin J, Cuff JF, Da C, Ball R, Bach R, Crespo A, Gong X, Welch CJ. Systematic approach to conformational sampling for assigning absolute configuration using vibrational circular dichroism. J Med Chem 2014; 57:477-94. [PMID: 24383452 DOI: 10.1021/jm401600u] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Systematic methods that speed-up the assignment of absolute configuration using vibrational circular dichrosim (VCD) and simplify its usage will advance this technique into a robust platform technology. Applying VCD to pharmaceutically relevant compounds has been handled in an ad hoc fashion, relying on fragment analysis and technical shortcuts to reduce the computational time required. We leverage a large computational infrastructure to provide adequate conformational exploration which enables an accurate assignment of absolute configuration. We describe a systematic approach for rapid calculation of VCD/IR spectra and comparison with corresponding measured spectra and apply this approach to assign the correct stereochemistry of nine test cases. We suggest moving away from the fragment approach when making VCD assignments. In addition to enabling faster and more reliable VCD assignments of absolute configuration, the ability to rapidly explore conformational space and sample conformations of complex molecules will have applicability in other areas of drug discovery.
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Affiliation(s)
- Edward C Sherer
- Merck Research Laboratories, Merck & Co., Inc., PO Box 2000, Rahway, New Jersey 07065, United States
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14
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Dahab AA. Rapid analysis of drug binding to β-cyclodextrin: part II substituents effect on physicochemical and co-conformational stability of drug/cyclodextrin complex. RSC Adv 2014. [DOI: 10.1039/c3ra47010e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
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15
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Abstract
A correlational study shows for the first time a quantitative substituent effect on Vibrational Circular Dichroism intensity.
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Affiliation(s)
- Piotr F. J. Lipiński
- Department of Neuropeptides
- Mossakowski Medical Research Center
- Polish Academy of Sciences
- 02-106 Warsaw, Poland
| | - Jan Cz. Dobrowolski
- National Medicines Institute
- 00-725 Warsaw, Poland
- Institute of Nuclear Chemistry and Technology
- 03-195 Warsaw, Poland
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16
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Weakley AT, Aston DE, Griffiths PR. Automatic baseline correction of vibrational circular dichroism spectra. APPLIED SPECTROSCOPY 2013; 67:1117-1126. [PMID: 24191375 DOI: 10.1366/13-07078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A three-phase, computational method for the baseline correction of vibrational circular dichroism (VCD) spectra has been proposed. In the first phase the raw spectrum is subdivided into m segments (or regions) resulting in p rough estimates of the baseline. A second phase uses gradient characteristics to discriminate between baseline and band response for each baseline, in turn. In the final phase all baselines are interrogated simultaneously by assigning the median estimate of each differential response’s distribution to the true baseline. Using VCD spectra of (R)-camphor as test cases, this work demonstrated that the accurate removal of baseline components is readily achievable with minimal user intervention. Baseline correction also demonstrated flexibility in that prior information, such as the symmetry of a baselinefree VCD spectrum, is readily used during the correction protocol. Although three adjustable parameters are present in the base algorithm, optimal performance and full automation were attainable following the use of analysis of variance (ANOVA) to analyze simulated bipolar spectra. These ANOVAs suggested that band point discrimination could be discarded and the remaining two default parameters adopted.
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17
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De Klerck K, Mangelings D, Vander Heyden Y. Supercritical fluid chromatography for the enantioseparation of pharmaceuticals. J Pharm Biomed Anal 2012; 69:77-92. [DOI: 10.1016/j.jpba.2012.01.021] [Citation(s) in RCA: 141] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 01/18/2012] [Accepted: 01/19/2012] [Indexed: 11/30/2022]
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18
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Aboel Dahab A, El-Hag D. Rapid analysis of NSAIDs binding to β-cyclodextrin using the simultaneous measurement of absorption and circular dichroism with a novel multi-cell low-volume device. Anal Bioanal Chem 2012; 404:1839-50. [DOI: 10.1007/s00216-012-6286-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2012] [Revised: 07/02/2012] [Accepted: 07/18/2012] [Indexed: 11/30/2022]
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19
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Gudla V, Balamurugan R. Synthesis of Arylnaphthalene Lignan Scaffold by Gold-Catalyzed Intramolecular Sequential Electrophilic Addition and Benzannulation. J Org Chem 2011; 76:9919-33. [DOI: 10.1021/jo201918d] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Vanajakshi Gudla
- School of Chemistry, University of Hyderabad, Gachibowli, Hyderabad 500046, India
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20
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Lunkley JL, Shirotani D, Yamanari K, Kaizaki S, Muller G. Chiroptical spectra of a series of tetrakis((+)-3-heptafluorobutylyrylcamphorato)lanthanide(III) with an encapsulated alkali metal ion: circularly polarized luminescence and absolute chiral structures for the Eu(III) and Sm(III) complexes. Inorg Chem 2011; 50:12724-32. [PMID: 22074461 DOI: 10.1021/ic201851r] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The luminescence and circularly polarized luminescence (CPL) spectra of M(I)[Eu((+)-hfbc)(4)] show a similar behavior to the exciton CD in the intraligand π-π* transitions when the alkali metal ions and solvents are manipulated. There is a difference in susceptibility in solvation toward the alkali metal ions but not toward the Eu(III) ion, as in the case of axially symmetric DOTA-type compounds. The remarkable CPL in the 4f-4f transitions provide much more information on the stereospecific formation of chiral Eu(III) complexes, since CPL spectroscopy is limited to luminescent species and reflects selectively toward helicity of the local structural environment around the lanthanide(III). While in comparison, exciton CD reveals the chiral structural information from the helical arrangement of the four bladed chelates. Of special importance, the observation of the highest CPL activities measured to date for lanthanide(III)-containing compounds (i.e., Eu and Sm) in solution supports the theory that the chirality of lanthanide(III) in the excited state corresponds to that in the ground state, which was derived from the exciton CD.
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Affiliation(s)
- Jamie L Lunkley
- Department of Chemistry, San José State University, One Washington Square, San José, California 95192-0101, USA
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21
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Sarabia F, Vivar-García C, García-Castro M, Martín-Ortiz J. Cyclic Sulfur Ylides Derived from Gleason-Type Chiral Auxiliaries for the Asymmetric Synthesis of Epoxy Amides. J Org Chem 2011; 76:3139-50. [DOI: 10.1021/jo1025964] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Francisco Sarabia
- Department of Organic Chemistry and ‡Department of Physical Chemistry, Faculty of Sciences, University of Malaga,. Campus de Teatinos s/n, 29071 Malaga, Spain
| | - Carlos Vivar-García
- Department of Organic Chemistry and ‡Department of Physical Chemistry, Faculty of Sciences, University of Malaga,. Campus de Teatinos s/n, 29071 Malaga, Spain
| | - Miguel García-Castro
- Department of Organic Chemistry and ‡Department of Physical Chemistry, Faculty of Sciences, University of Malaga,. Campus de Teatinos s/n, 29071 Malaga, Spain
| | - Jorge Martín-Ortiz
- Department of Organic Chemistry and ‡Department of Physical Chemistry, Faculty of Sciences, University of Malaga,. Campus de Teatinos s/n, 29071 Malaga, Spain
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22
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Shen J, Zhu C, Reiling S, Vaz R. A novel computational method for comparing vibrational circular dichroism spectra. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2010; 76:418-22. [PMID: 20451442 DOI: 10.1016/j.saa.2010.04.014] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2010] [Revised: 04/09/2010] [Accepted: 04/14/2010] [Indexed: 05/23/2023]
Abstract
A novel method, SimIR/VCD, for comparing experimental and calculated VCD (vibrational circular dichroism) spectra is developed, based on newly defined spectra similarities. With computationally optimized frequency scaling and shifting, a calculated spectrum can be easily identified to match an observed spectrum, which leads to an unbiased molecular chirality assignment. The time-consuming manual band-fitting work is greatly reduced. With (1S)-(-)-alpha-pinene as an example, it demonstrates that the calculated VCD similarity is correlated with VCD spectra matching quality and has enough sensitivity to identify variations in the spectra. The study also compares spectra calculated using different DFT methods and basis sets. Using this method should facilitate the spectra matching, reduce human error and provide a confidence measure in the chiral assignment using VCD spectroscopy.
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Affiliation(s)
- Jian Shen
- Chemical and Analytical Science, Sanofi Aventis Inc., 1041 Route 202-206, Bridgewater, NJ 08807, USA.
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23
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Abstract
This perspective gives an introduction into the design of luminescent lanthanide(iii)-containing complexes possessing chiral properties and used to probe biological materials. The first part briefly describes general principles, focusing on the optical aspect (i.e. lanthanide luminescence, sensitization processes) of the most emissive trivalent lanthanide ions, europium and terbium, incorporated into molecular luminescent edifices. This is followed by a short discussion on the importance of chirality in the biological and pharmaceutical fields. The second part is devoted to the assessment of the chiroptical spectroscopic tools available (typically circular dichroism and circularly polarized luminescence) and the strategies used to introduce a chiral feature into luminescent lanthanide(iii) complexes (chiral structure resulting from a chiral arrangement of the ligand molecules surrounding the luminescent center or presence of chiral centers in the ligand molecules). Finally, the last part illustrates these fundamental principles with recent selected examples of such chiral luminescent lanthanide-based compounds used as potential probes of biomolecular substrates.
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Affiliation(s)
- Gilles Muller
- Department of Chemistry, San José State University, San José, CA 95192-0101, USA.
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Discovery of a new series of monoamine reuptake inhibitors, the 1-amino-3-(1H-indol-1-yl)-3-phenylpropan-2-ols. Bioorg Med Chem Lett 2009; 19:5029-32. [DOI: 10.1016/j.bmcl.2009.07.053] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Revised: 07/06/2009] [Accepted: 07/08/2009] [Indexed: 11/23/2022]
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Moussa A, Pham C, Bommireddy S, Muller G. Importance of hydrogen-bonding sites in the chiral recognition mechanism between racemic D3 terbium(III) complexes and amino acids. Chirality 2009; 21:497-506. [PMID: 18698640 PMCID: PMC2668746 DOI: 10.1002/chir.20628] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The perturbation of the racemic equilibrium of luminescent D3 terbium(III) complexes with chelidamic acid (CDA), a hydroxylated derivative of 2,6-pyridine-dicarboxylic acid (DPA), by added chiral biomolecules such as L-amino acids has been studied using circularly polarized luminescence and 13C NMR spectroscopy. It is shown in this work that the chiral-induced equilibrium shift of [Tb(CDA)3](6-) by L-amino acids (i.e. L-proline or L-arginine) was largely influenced by the hydrogen-bonding networks formed between the ligand interface of racemic [Tb(CDA)3](6-) and these added chiral agents. The capping of potential hydrogen-bonding sites by acetylation in L-proline led to a approximately 100-fold drop in the induced optical activity of the [Tb(CDA)3](6-):N-acetyl-L-proline system. This result suggested that the hydrogen-bonding networks serve as the basis for further noncovalent discriminatory interactions between racemic [Tb(CDA)3](6-) and added L-amino acids.
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Affiliation(s)
- Ahmed Moussa
- Department of Chemistry, San José State University, One Washington Square, San José, California 95192-0101, USA
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Affiliation(s)
- Timothy J Ward
- Millsaps College 1701 North State Street, Box 150306, Jackson, Mississippi 39210, USA.
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