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Afanasyev OI, Podyacheva E, Rudenko A, Tsygankov AA, Makarova M, Chusov D. Redox Condensations of o-Nitrobenzaldehydes with Amines under Mild Conditions: Total Synthesis of the Vasicinone Family. J Org Chem 2020; 85:9347-9360. [PMID: 32515592 DOI: 10.1021/acs.joc.0c00794] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A total synthesis of the vasicinone family of natural products from bulk chemicals was developed. Reductive condensation of o-nitrobenzaldehydes with amines utilizing iron pentacarbonyl as a reducing agent followed by subsequent oxidation leads to a great variety of polycyclic nitrogen-containing heterocycles under mild conditions. Enantiomerically pure vasicinone, rutaecarpine, isaindigotone, and luotonin were synthesized from readily available starting materials like hydroxyproline, nitrobenzaldehyde, pyrrolidine, and piperidine in two to four operational steps without chromatography. The antifungal activity of all products was tested.
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Affiliation(s)
- Oleg I Afanasyev
- A.N. Nesmeyanov Institute of Organoelement Compounds of the Russian Academy of Sciences, Vavilova St. 28, Moscow 119991, Russian Federation
| | - Evgeniya Podyacheva
- A.N. Nesmeyanov Institute of Organoelement Compounds of the Russian Academy of Sciences, Vavilova St. 28, Moscow 119991, Russian Federation
| | - Alexander Rudenko
- Higher Chemical College, Dmitry Mendeleev University of Chemical Technology of Russia, Miusskaya sq. 9, Moscow 125047, Russian Federation
| | - Alexey A Tsygankov
- A.N. Nesmeyanov Institute of Organoelement Compounds of the Russian Academy of Sciences, Vavilova St. 28, Moscow 119991, Russian Federation
| | - Maria Makarova
- A.N. Nesmeyanov Institute of Organoelement Compounds of the Russian Academy of Sciences, Vavilova St. 28, Moscow 119991, Russian Federation.,Higher Chemical College, Dmitry Mendeleev University of Chemical Technology of Russia, Miusskaya sq. 9, Moscow 125047, Russian Federation
| | - Denis Chusov
- A.N. Nesmeyanov Institute of Organoelement Compounds of the Russian Academy of Sciences, Vavilova St. 28, Moscow 119991, Russian Federation.,G.V. Plekhanov Russian University of Economics, 36 Stremyanny Per., Moscow 117997, Russia
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Claes L, Janssen M, De Vos DE. Organocatalytic Decarboxylation of Amino Acids as a Route to Bio‐based Amines and Amides. ChemCatChem 2019. [DOI: 10.1002/cctc.201900800] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Laurens Claes
- Department of Microbial and Molecular Systems Centre for Membrane Separations, Adsorption, Catalysis, and Spectroscopy forSustainable Solutions (cMACS) KU Leuven Celestijnenlaan 200F box 2454 3001 Leuven Belgium
| | - Michiel Janssen
- Department of Microbial and Molecular Systems Centre for Membrane Separations, Adsorption, Catalysis, and Spectroscopy forSustainable Solutions (cMACS) KU Leuven Celestijnenlaan 200F box 2454 3001 Leuven Belgium
| | - Dirk E. De Vos
- Department of Microbial and Molecular Systems Centre for Membrane Separations, Adsorption, Catalysis, and Spectroscopy forSustainable Solutions (cMACS) KU Leuven Celestijnenlaan 200F box 2454 3001 Leuven Belgium
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De Schouwer F, Claes L, Vandekerkhove A, Verduyckt J, De Vos DE. Protein-Rich Biomass Waste as a Resource for Future Biorefineries: State of the Art, Challenges, and Opportunities. CHEMSUSCHEM 2019; 12:1272-1303. [PMID: 30667150 DOI: 10.1002/cssc.201802418] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 01/22/2019] [Indexed: 06/09/2023]
Abstract
Protein-rich biomass provides a valuable feedstock for the chemical industry. This Review describes every process step in the value chain from protein waste to chemicals. The first part deals with the physicochemical extraction of proteins from biomass, hydrolytic degradation to peptides and amino acids, and separation of amino acid mixtures. The second part provides an overview of physical and (bio)chemical technologies for the production of polymers, commodity chemicals, pharmaceuticals, and other fine chemicals. This can be achieved by incorporation of oligopeptides into polymers, or by modification and defunctionalization of amino acids, for example, their reduction to amino alcohols, decarboxylation to amines, (cyclic) amides and nitriles, deamination to (di)carboxylic acids, and synthesis of fine chemicals and ionic liquids. Bio- and chemocatalytic approaches are compared in terms of scope, efficiency, and sustainability.
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Affiliation(s)
- Free De Schouwer
- Centre for Surface Chemistry and Catalysis, Department of Microbial and Molecular Systems, KU Leuven, Celestijnenlaan 200F, post box 2461, 3001, Heverlee, Belgium
| | - Laurens Claes
- Centre for Surface Chemistry and Catalysis, Department of Microbial and Molecular Systems, KU Leuven, Celestijnenlaan 200F, post box 2461, 3001, Heverlee, Belgium
| | - Annelies Vandekerkhove
- Centre for Surface Chemistry and Catalysis, Department of Microbial and Molecular Systems, KU Leuven, Celestijnenlaan 200F, post box 2461, 3001, Heverlee, Belgium
| | - Jasper Verduyckt
- Centre for Surface Chemistry and Catalysis, Department of Microbial and Molecular Systems, KU Leuven, Celestijnenlaan 200F, post box 2461, 3001, Heverlee, Belgium
| | - Dirk E De Vos
- Centre for Surface Chemistry and Catalysis, Department of Microbial and Molecular Systems, KU Leuven, Celestijnenlaan 200F, post box 2461, 3001, Heverlee, Belgium
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Häussermann A, Rominger F, Straub BF. CO2 on a tightrope: stabilization, room-temperature decarboxylation, and sodium-induced carboxylate migration. Chemistry 2012; 18:14174-85. [PMID: 22997025 DOI: 10.1002/chem.201202298] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Indexed: 11/11/2022]
Abstract
A sterically shielded 3-substituted zwitterionic N,N-dimethylisotryptammonium carboxylate has been synthesized by consecutive chemoselective double alkylation of indole. The carboxylate undergoes a quantitative and unusually facile decarboxylation in dimethyl sulfoxide (DMSO) or dimethyl formamide (DMF) at room temperature. The breaking of a nearly equidistant hydrogen bond by solvent molecules initiates heterolytic C-C cleavage. The decarboxylation rate decreases with increasing CO(2) partial pressure, proving the competitiveness of protonation and re-carboxylation of the carbanionic intermediate. Corresponding spiro compounds containing silylene and stannylene moieties show high thermal stability. Addition of an excess of methyllithium to the sodium salt triggers a reaction sequence comprising a deprotonation, carboxylate transfer, and nucleophilic trapping of the rearranged carboxylate by another equivalent of methyllithium. Hydrolytic work-up of the geminal diolate leads to an acetyl product. The role of the sodium counterion and the mechanism of the rearrangement have been unraveled by deuteration experiments.
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Affiliation(s)
- Achim Häussermann
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Germany
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5
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Pham SQ, Gao P, Li Z. Engineering of recombinant E. coli cells co-expressing P450pyrTM monooxygenase and glucose dehydrogenase for highly regio- and stereoselective hydroxylation of alicycles with cofactor recycling. Biotechnol Bioeng 2012; 110:363-73. [PMID: 22886996 DOI: 10.1002/bit.24632] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2012] [Revised: 07/20/2012] [Accepted: 07/25/2012] [Indexed: 11/07/2022]
Abstract
E. coli (P450pyrTM-GDH) with dual plasmids, pETDuet containing P450pyr triple mutant I83H/M305Q/A77S (P450pyrTM) and ferredoxin reductase (FdR) genes and pRSFDuet containing glucose dehydrogenase (GDH) and ferredoxin (Fdx) genes, was engineered to show a high activity (12.7 U g⁻¹ cdw) for the biohydroxylation of N-benzylpyrrolidine 1 and a GDH activity of 106 U g⁻¹ protein. The E. coli cells were used as efficient biocatalysts for highly regio- and stereoselective hydroxylation of alicyclic substrates at non-activated carbon atom with enhanced productivity via intracellular recycling of NAD(P)H. Hydroxylation of N-benzylpyrrolidine 1 with resting cells in the presence of glucose showed excellent regio- and stereoselectivity, giving (S)-N-benzyl-3-hydroxypyrrolidine 2 in 98% ee as the sole product in 9.8 mM. The productivity is much higher than that of the same biohydroxylation using E. coli (P450pyrTM)b without expressing GDH. E. coli (P450pyrTM-GDH) was found to be highly regio- and stereoselective for the hydroxylation of N-benzylpyrrolidin-2-one 3, improving the regioselectivity from 90% of the wild-type P450pyr to 100% and giving (S)-N-benzyl-4-hydroxylpyrrolidin-2-one 4 in 99% ee as the sole product. A high activity of 15.5 U g⁻¹ cdw was achieved and (S)-4 was obtained in 19.4 mM. E. coli (P450pyrTM-GDH) was also found to be highly regio- and stereoselective for the hydroxylation of N-benzylpiperidin-2-one 5, increasing the ee of the product (S)-N-benzyl-4-hydroxy-piperidin-2-one 6 to 94% from 33% of the wild-type P450pyr. A high activity of 15.8 U g⁻¹ cdw was obtained and (S)-6 was produced in 3.3 mM as the sole product. E. coli (P450pyrTM-GDH) represents the most productive system known thus far for P450-catalyzed hydroxylations with cofactor recycling, and the hydroxylations with E. coli (P450pyrTM-GDH) provide with simple and useful syntheses of (S)-2, (S)-4, and (S)-6 that are valuable pharmaceutical intermediates and difficult to prepare.
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Affiliation(s)
- Son Q Pham
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117576, Singapore
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Campiglia P, Aquino C, Bertamino A, De Simone N, Sala M, Castellano S, Santoriello M, Grieco P, Novellino E, Gomez-Monterrey IM. Unprecedented synthesis of a novel amino quinone ring system via oxidative decarboxylation of quinone-based α,α-amino esters. Org Biomol Chem 2010; 8:622-7. [DOI: 10.1039/b918898c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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Wilken J, Martens J. Enantioselective Catalytic Borane Reduction of Prochiral Ketones: Synthesis and Application of New Rigid β-Amino Alcohols with a Cycloalkanol Subunit. SYNTHETIC COMMUN 2006. [DOI: 10.1080/00397919608003849] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Wilken J, Wallbaum S, Saak W, Haase D, Pohl S, Martens J, Patkar LN, Dixit AN, Chittari P, Rajappa S. Utilization of Industrial Waste Materials, 6. Utilization of Derivatives of the Bicyclic Proline Analog (all-R)-Octahydrocyclopenta[b]pyrrol-2-carboxylic Acid in the Stereoselective Synthesis. European J Org Chem 2006. [DOI: 10.1002/jlac.199619960610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Wolyniak CJ, Sacks GL, Pan BS, Brenna JT. Carbon Position-Specific Isotope Analysis of Alanine and Phenylalanine Analogues Exhibiting Nonideal Pyrolytic Fragmentation. Anal Chem 2005; 77:1746-52. [PMID: 15762581 DOI: 10.1021/ac048524v] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recent advances in gas chromatography combustion-isotope ratio mass spectrometry (GCC-IRMS) has made compound-specific isotope analysis routine, but reports on position-specific isotopic analysis are still scarce. On-line GC-pyrolysis (Py) coupled to GCC-IRMS is reported here for isolation and isotopic characterization of alaninol and phenethylamine, analogues of alanine and phenylalanine, respectively. Ideally, pyrolytic fragments will originate from unique sites within the parent molecule, and isotope ratios for each position within the parent can either be measured directly or calculated from fragment isotope ratios without substantially degrading the analytical precision. Alaninol pyrolysis yielded several fragments, of which CO and CH4 were used for isotope ratio calculations. Isotope labeling experiments showed that CO derived entirely from the C(1) position, while all three positions of alaninol contributed to CH4 (29.0 +/- 0.3% from C(1), 3.6 +/- 0.2% from C(2), and 66.9 +/- 1.1% from C(3)). We demonstrate iterative use of mass balance to calculate isotope ratios from all positions despite the nonideal positional fidelity of CH4. Pyrolysis of phenethylamine generated benzene and toluene fragments. Benzene derived entirely from C(ring), and toluene was proportionately formed from C(3) and C(ring). Relative intramolecular isotope ratios (Deltadelta13C) were calculated directly from delta13C of fragments or indirectly by mass balance. Though the C(3) isotope ratio was calculated from the benzene and toluene fragments, propagation of errors showed that the final precision of the determination was degraded due to the small contribution that C(3) makes to toluene. Samples of each amino acid from four different vendors showed natural variability between sources, especially at the C(1) position of alaninol (range of Deltadelta13C approximately 50 per thousand). The average precision was SD(Deltadelta13C) < 0.20 per thousand for directly measured positions of alaninol and phenethylamine. The precision of indirectly measured positions was poorer (SD(Deltadelta13C) = 0.94 per thousand for alaninol, 6.54 per thousand for phenethylamine) due to propagation of errors. These data demonstrate that GC-Py-GCC-IRMS data can be used to extract high-precision isotope ratios from amino acids despite nonideal positional fidelity in fragments and that natural intramolecular variability in delta13C can be used to distinguish different sources of amino acids.
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Affiliation(s)
- Christopher J Wolyniak
- Division of Nutritional Sciences, Savage Hall, Cornell University, Ithaca, New York 14853, USA
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Li Z, Feiten HJ, Chang D, Duetz WA, van Beilen JB, Witholt B. Preparation of (R)- and (S)-N-protected 3-hydroxypyrrolidines by hydroxylation with Sphingomonas sp. HXN-200, a highly active, regio- and stereoselective, and easy to handle biocatalyst. J Org Chem 2001; 66:8424-30. [PMID: 11735520 DOI: 10.1021/jo015826d] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hydroxylation of N-benzylpyrrolidine 8 with resting cells of Sphingomonas sp. HXN-200 gave N-benzyl-3-hydroxypyrrolidine 15 in 53% ee (S) with an activity of 5.8 U/g CDW. By changing the "docking/protecting group" in pyrrolidines, hydroxylation activity and enantioselectivity were further improved and the enantiocomplementary formation of 3-hydroxypyrrolidines was achieved: hydroxylation of N-benzoyl-, N-benzyloxycarbonyl-, N-phenoxycarbonyl-, and N-tert-butoxycarbonyl-pyrrolidines 9-12 gave the corresponding 3-hydroxypyrrolidines 16-19 in ee of 52% (R), 75% (R), 39% (S), and 23% (R), respectively, with an activity of 2.2, 16, 14, and 24 U/g CDW, respectively. Simple crystallizations increased the ee of 16-18 to 95% (R), 98% (R), and 96% (S), respectively. Hydroxylation of pyrrolidines 8-12 with soluble cell-free extracts of Sphingomonas sp. HXN-200 and equimolar NADH gave 3-hydroxypyrrolidines 15-19 in nearly the same ee as the products generated by whole cell transformation, suggesting that this strain possesses a novel soluble alkane monooxygenase. Cells of Sphingomonas sp. HXN-200 were produced in large amounts and could be stored at -80 degrees C for 2 years without significant loss of activity. The frozen cells can be thawed and resuspended for biohydroxylation, providing a highly active and easy to handle biocatalyst for the regio- and stereoselective hydroxylation of nonactivated carbon atoms. These cells were used to prepare 1.0-3.2 g (66.4-93.5% yield) of 3-hydroxypyrrolidines 16-19 by hydroxylation of pyrrolidines 9-12 on 0.9-2 L scale. Preparative hydroxylation was also achieved with growing cells as biocatalysts; hydroxylation of pyrrolidine 11 on 1 L scale gave 1.970 g (79.7% yield) of 3-hydroxypyrrolidine 18.
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Affiliation(s)
- Z Li
- Institute of Biotechnology, ETH Zurich, Hoenggerberg, CH-8093 Zurich, Switzerland.
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Diastereoselective hydroboration of chiral enamines using an enantiomerically pure amine from an industrial waste material as the source of chirality. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s0957-4166(00)00169-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Bhushan R, Martens J, Thiongo GT. Direct thin layer chromatography enantioresolution of some basic DL-amino acids using a pharmaceutical industry waste as chiral impregnating reagent. J Pharm Biomed Anal 2000; 21:1143-7. [PMID: 10708398 DOI: 10.1016/s0731-7085(99)00203-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Direct enantiomeric resolution of DL-arginine, DL-histidine, DL-lysine, DL-valine and DL-leucine into their enantiomers was achieved by thin layer chromatography (TLC) on silica gel plates impregnated with optically pure (1R, 3R, 5R)-2-azabicyclo[3,3,0]octan-3-carbo-xylic acid (0.011 M) as a chiral selector which is a waste of a pharmaceutical industry. Different combinations of acetonitrile-methanol-water were found to be successful in resolving the DL-amino acids. The spots were detected by ninhydrin (0.2% in acetone) and the detection limit was 0.66 microg.
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Affiliation(s)
- R Bhushan
- Department of Chemistry, University of Roorkee, India.
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Kossenjans M, Martens J. Highly stereoselective synthesis of 1,3-aminoalcohols via Mannich reactions. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0957-4166(99)00342-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Li Z, Feiten HJ, van Beilen JB, Duetz W, Witholt B. Preparation of optically active N-benzyl-3-hydroxypyrrolidine by enzymatic hydroxylation. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0957-4166(99)00124-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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15
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Wilken J, Thorey C, Gröger H, Haase D, Saak W, Pohl S, Muzart J, Martens J. Utilization of Industrial Waste Materials, 11. Synthesis of New, Chiral β-sec-Amino Alcohols – Diastereodivergent Addition of Grignard Reagents to α-Amino Aldehydes Based on the (all-R)-2-Azabicyclo[3.3.0]octane System. ACTA ACUST UNITED AC 1997. [DOI: 10.1002/jlac.199719971016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Bhushan R, Martens J, Wallbaum S, Joshi S, Parshad V. TLC resolution of enantiomers of amino acids and dansyl derivatives using (1R,3R,5R)-2-azabicyclo[3,3,0]octan-3-carboxylic acid as impregnating reagent. Biomed Chromatogr 1997; 11:286-8. [PMID: 9376710 DOI: 10.1002/(sici)1099-0801(199709)11:5<286::aid-bmc698>3.0.co;2-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The enantiomeric resolution of certain amino acids and some of their dansyl derivatives was achieved on thin silica gel plates impregnated with (1R,3R,5R)- 2-Azabicyclo[3,3,0]octan-3-carboxylic acid, which is an industrial waste material, and a proline analogue non proteinogenic alpha-amino acid. Different combination of 0.5 M NaCl-MeCN were found to be successful in resolving dansyl-DL-amino acids; addition of methanol was required in some cases. Spots were visualised using a fixed wavelength (254 nm) ultraviolet chamber. Resolution of DL-amino acids was successful in different combinations of MeCN-MeOH-H2O and detection was made with ninhydrin (0.2% in acetone).
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Affiliation(s)
- R Bhushan
- Department of Chemistry, University of Roorkee, India
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Wilken J, Gröger H, Kossenjans M, Martens J. Synthesis and application of new (threo)- and (erythro)-amino alcohols based on the octahydro-cyclopenta[b]pyrrole system in the catalytic enantioselective addition of diethylzinc to benzaldehyde. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0957-4166(97)00327-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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18
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Wilken J, Martens J. Utilization of Industrial Waste Materials, 7. – Synthesis of New, Chiral β-sec-Amino Alcohols – Regio- and Diastereoselective α-Hydroxyalkylation of (1R,5R)-2-Azabicyclo[3.3.0]octane. European J Org Chem 1997. [DOI: 10.1002/jlac.199719970318] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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19
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20
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Ennis MD, Hoffman RL, Ghazal NB, Old DW, Mooney PA. Asymmetric Synthesis of Cis-Fused Bicyclic Pyrrolidines and Pyrrolidinones via Chiral Polycyclic Lactams. J Org Chem 1996. [DOI: 10.1021/jo960185l] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michael D. Ennis
- Structural, Analytical & Medicinal Chemistry, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001
| | - Robert L. Hoffman
- Structural, Analytical & Medicinal Chemistry, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001
| | - Nabil B. Ghazal
- Structural, Analytical & Medicinal Chemistry, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001
| | - David W. Old
- Structural, Analytical & Medicinal Chemistry, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001
| | - Pamela A. Mooney
- Structural, Analytical & Medicinal Chemistry, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001
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Eilers J, Wilken J, Martens J. Syntheses of new chiral 1,2-diamines and δ-amino-alcohols and their application in catalytic enantioselective CC bond formations at an elevated temperature of up to 110 °C. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/0957-4166(96)00289-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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