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Vera S, Vázquez A, Rodriguez R, Pozo SD, Urruzuno I, Cózar AD, Mielgo A, Palomo C. Synthesis of β-Hydroxy α-Amino Acids Through Brønsted Base-Catalyzed syn-Selective Direct Aldol Reaction of Schiff Bases of Glycine o-Nitroanilide. J Org Chem 2021; 86:7757-7772. [PMID: 33998227 PMCID: PMC9490875 DOI: 10.1021/acs.joc.1c00406] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
![]()
Here
we report the highly enantio- and syn-selective
synthesis of β-hydroxy α-amino acids from glycine imine
derivatives under Brønsted base (BB) catalysis. The key of this
approach is the use of benzophenone-derived imine of glycine o-nitroanilide as a pronucleophile, where the o-nitroanilide framework provides an efficient hydrogen-bonding platform
that accounts for nucleophile reactivity and diastereoselectivity.
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Affiliation(s)
- Silvia Vera
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Ana Vázquez
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Ricardo Rodriguez
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Sandra Del Pozo
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Iñaki Urruzuno
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Abel de Cózar
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain.,IKERBASQUE, Basque Foundation for Science, 48009 Bilbao, Spain
| | - Antonia Mielgo
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Claudio Palomo
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
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2
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Han X, Gao F, Li C, Fang D, Xie X, Zhou Y, Liu H. Synthesis of Highly Fused Pyrano[2,3-b]pyridines via Rh(III)-Catalyzed C–H Activation and Intramolecular Cascade Annulation under Room Temperature. J Org Chem 2020; 85:6281-6294. [DOI: 10.1021/acs.joc.9b03102] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xu Han
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Feng Gao
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
| | - Chunpu Li
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Daqing Fang
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Xiong Xie
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Yu Zhou
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Hong Liu
- State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
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3
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Kondo Y, Morisaki K, Hirazawa Y, Morimoto H, Ohshima T. A Convenient Preparation Method for Benzophenone Imine Catalyzed by Tetrabutylammonium Fluoride. Org Process Res Dev 2019. [DOI: 10.1021/acs.oprd.9b00226] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Yuta Kondo
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Kazuhiro Morisaki
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Yoshinobu Hirazawa
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Hiroyuki Morimoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Takashi Ohshima
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
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Abstract
This Review is devoted to the chemistry of macrocyclic peptides having heterocyclic fragments in their structure. These motifs are present in many natural products and synthetic macrocycles designed against a particular biochemical target. Thiazole and oxazole are particularly common constituents of naturally occurring macrocyclic peptide molecules. This frequency of occurrence is because the thiazole and oxazole rings originate from cysteine, serine, and threonine residues. Whereas other heteroaryl groups are found less frequently, they offer many insightful lessons that range from conformational control to receptor/ligand interactions. Many options to develop new and improved technologies to prepare natural products have appeared in recent years, and the synthetic community has been pursuing synthetic macrocycles that have no precedent in nature. This Review attempts to summarize progress in this area.
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Affiliation(s)
- Ivan V Smolyar
- Department of Chemistry , Moscow State University , Leninskije Gory , 199991 Moscow , Russia
| | - Andrei K Yudin
- Davenport Research Laboratories, Department of Chemistry , University of Toronto , 80 St. George Street , Toronto , Ontario M5S 3H6 , Canada
| | - Valentine G Nenajdenko
- Department of Chemistry , Moscow State University , Leninskije Gory , 199991 Moscow , Russia
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5
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Adam A, Mehrparvar S, Haberhauer G, Glüsenkamp KH, Wölper C. N-Aryl Imidazole Platforms - Synthesis and Structural Investigation. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Abdulselam Adam
- Institut für Organische Chemie; Universität Duisburg-Essen; Universitätsstr. 7 45117 Essen Germany
| | - Saber Mehrparvar
- Institut für Organische Chemie; Universität Duisburg-Essen; Universitätsstr. 7 45117 Essen Germany
| | - Gebhard Haberhauer
- Institut für Organische Chemie; Universität Duisburg-Essen; Universitätsstr. 7 45117 Essen Germany
| | | | - Christoph Wölper
- Institut für Organische Chemie; Universität Duisburg-Essen; Universitätsstr. 7 45117 Essen Germany
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6
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Shimizu Y, Shoji Y, Hashizume D, Nagata Y, Fukushima T. Sensing the chirality of various organic solvents by helically arranged π-blades. Chem Commun (Camb) 2018; 54:12314-12317. [DOI: 10.1039/c8cc06277c] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The three-bladed dynamic propeller molecule exhibits a chiroptical property in various chiral organic solvents.
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Affiliation(s)
- Yuki Shimizu
- Laboratory for Chemistry and Life Science
- Institute of Innovative Research
- Tokyo Institute of Technology
- Yokohama 226-8503
- Japan
| | - Yoshiaki Shoji
- Laboratory for Chemistry and Life Science
- Institute of Innovative Research
- Tokyo Institute of Technology
- Yokohama 226-8503
- Japan
| | - Daisuke Hashizume
- RIKEN Center for Emergent Matter Science (CEMS)
- Saitama 351-0198
- Japan
| | - Yuuya Nagata
- Department of Synthetic Chemistry and Biological Chemistry
- Graduate School of Engineering
- Kyoto University
- Kyoto 615-8510
- Japan
| | - Takanori Fukushima
- Laboratory for Chemistry and Life Science
- Institute of Innovative Research
- Tokyo Institute of Technology
- Yokohama 226-8503
- Japan
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7
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Adam A, Haberhauer G. Switching Process Consisting of Three Isomeric States of an Azobenzene Unit. J Am Chem Soc 2017; 139:9708-9713. [PMID: 28682626 DOI: 10.1021/jacs.7b05316] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Azobenzene and its derivatives are among the most commonly used switching units in organic chemistry. The switching process consists of two states, in which the trans isomer has a stretched and the cis isomer a compact form. Here, we have designed a system in which all isomeric states of an azobenzene moiety (trans → cis-(M) → cis-(P)) are passed step by step. The first step involves a change in the distance between the benzene units, which is common for azobenzene derivatives. In the second step an inversion of the helicity (M→P) of the cis azobenzene unit takes place. The third step leads back to the stretched trans isomer. This switching cycle is achieved by coupling the azobenzene unit with two chiral clamps and with a further azobenzene switching unit.
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Affiliation(s)
- Abdulselam Adam
- Institut für Organische Chemie, Universität Duisburg-Essen , Universitätsstraße 7, D-45117 Essen, Germany
| | - Gebhard Haberhauer
- Institut für Organische Chemie, Universität Duisburg-Essen , Universitätsstraße 7, D-45117 Essen, Germany
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8
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Adam A, Haberhauer G, Wölper C. Bio-inspired Herringbone Foldamers: Strategy for Changing the Structure of Helices. J Org Chem 2017; 82:4203-4215. [PMID: 28357862 DOI: 10.1021/acs.joc.7b00185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cyclic oligomers of azole peptides were isolated from a multitude of marine organisms and were used for a large number of molecular machines. As shown previously, oligomers derived from achiral imidazole amino acids fold into canonical helices. Here we show that a minor change, the introduction of a methyl group in the δ position, results in a significant change in the secondary structure of the corresponding oligomers. Instead of a canonical helix, a noncanonical herringbone helix is formed. In the latter, the slope along the helix changes its sign at least twice per turn. This strategy allows a remarkable change of the secondary structure via a small modification. By means of enantiomerically pure amino acids, we were able to control, for the first time, both the helicity of the helix and the form of the herringbone. The investigation of the underlying herringbone basic element and its folding to a noncanonical helix were conducted by NMR and CD spectroscopy, as well as by X-ray crystallography and quantum chemical calculations.
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Affiliation(s)
- Abdulselam Adam
- Institut für Organische Chemie, Universität Duisburg-Essen , Universitätsstr. 7, D-45117 Essen, Germany
| | - Gebhard Haberhauer
- Institut für Organische Chemie, Universität Duisburg-Essen , Universitätsstr. 7, D-45117 Essen, Germany
| | - Christoph Wölper
- Institut für Organische Chemie, Universität Duisburg-Essen , Universitätsstr. 7, D-45117 Essen, Germany
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9
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Masnovi J, Banger KK, Fanwick PE, Hepp AF. Structural characterization of copper–indium chalcopyrite precursors (PPh3)2CuIn(ER)4 [R = CH3, E = S and R = Ph, E = S and Se]. Polyhedron 2015. [DOI: 10.1016/j.poly.2015.09.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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10
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Virieux D, Sevrain N, Ayad T, Pirat JL. Helical Phosphorus Derivatives. ADVANCES IN HETEROCYCLIC CHEMISTRY 2015. [DOI: 10.1016/bs.aihch.2015.06.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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11
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Landman M, Levell T, van Rooyen PH, Conradie J. Conformation analysis of triphenylphosphine in trans and cis triphenylphosphine-substituted Fischer carbene complexes. J Mol Struct 2014. [DOI: 10.1016/j.molstruc.2014.02.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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12
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Saito N, Terakawa R, Yamaguchi M. Synthesis, π-face-selective aggregation, and π-face chiral recognition of configurationally stable C(3)-symmetric propeller-chiral molecules with a π-core. Chemistry 2014; 20:5601-7. [PMID: 24737294 DOI: 10.1002/chem.201400094] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Indexed: 11/08/2022]
Abstract
The C3 -symmetric propeller-chiral compounds (P,P,P)-1 and (M,M,M)-1 with planar π-cores perpendicular to the C3 -axis were synthesized in optically pure states. (P,P,P)-1 possesses two distinguishable propeller-chiral π-faces with rims of different heights named the (P/L)-face and (P/H)-face. Each face is configurationally stable because of the rigid structure of the helicenes contained in the π-core. (P,P,P)-1 formed dimeric aggregates in organic solutions as indicated by the results of (1) H NMR, CD, and UV/Vis spectroscopy and vapor pressure osmometry analyses. The (P/L)/(P/L) interactions were observed in the solid state by single-crystal X-ray analysis, and they were also predominant over the (P/H)/(P/H) and (P/L)/(P/H) interactions in solution, as indicated by the results of (1) H and 2D NMR spectroscopy analyses. The dimerization constant was obtained for a racemic mixture, which showed that the heterochiral (P,P,P)-1/(M,M,M)-1 interactions were much weaker than the homochiral (P,P,P)-1/(P,P,P)-1 interactions. The results indicated that the propeller-chiral (P/L)-face interacts with the (P/L)-face more strongly than with the (P/H)-face, (M/L)-face, and (M/H)-face. The study showed the π-face-selective aggregation and π-face chiral recognition of the configurationally stable propeller-chiral molecules.
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Affiliation(s)
- Nozomi Saito
- Department of Organic Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba, Sendai 980-8578 (Japan), Fax: (+81) 22-795-6811; Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, 6-3 Aoba, Sendai 980-8578 (Japan)
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13
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Strongly underestimated dispersion energy in cryptophanes and their complexes. Nat Commun 2014; 5:3542. [DOI: 10.1038/ncomms4542] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 03/04/2014] [Indexed: 11/08/2022] Open
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14
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Puigjaner C, Vela S, Font-Bardia M, Novoa JJ. The polymorphism of a triarylphosphine oxide: a case of missing isomers. CrystEngComm 2014. [DOI: 10.1039/c4ce00498a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An experimental and computational study of the polymorphism of o-nitrophenyldiphenylphosphine oxide (1) has been carried out raising the question of why the anti polymorphs, more stable than the observed syn conformations according to our computations, have not been found.
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Affiliation(s)
- Cristina Puigjaner
- Unitat de Polimorfisme i Calorimetria
- Centres Cientificotècnics
- Universitat de Barcelona
- 08028 Barcelona, Spain
| | - Sergi Vela
- Departament de Química Física & IQTCUB
- Facultat de Química
- Universitat de Barcelona
- Barcelona, Spain
| | - Mercè Font-Bardia
- Unitat de Difracció de Raigs X
- Centres Cientificotècnics
- Universitat de Barcelona
- 08028 Barcelona, Spain
| | - Juan J. Novoa
- Departament de Química Física & IQTCUB
- Facultat de Química
- Universitat de Barcelona
- Barcelona, Spain
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15
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A very stable complex of a modified marine cyclopeptide with chloroform. Nat Commun 2013; 4:2945. [DOI: 10.1038/ncomms3945] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 11/15/2013] [Indexed: 12/18/2022] Open
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16
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Characterization of acetylacetonato carbonyl diphenyl-2-pyridylphosphine rhodium(I): Comparison with other carbonyl complexes. J Mol Struct 2013. [DOI: 10.1016/j.molstruc.2013.01.061] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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17
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Stuurman NF, Muller A, Conradie J. Structural trends in [Rh(PhCOCHCO(CH2)nCH3)(CO)(PPh3)] (n = 0–3) and related complexes: crystal structure of [Rh(PhCOCHCO(CH2)2CH3)(CO)(PPh3)]. TRANSIT METAL CHEM 2013. [DOI: 10.1007/s11243-013-9708-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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18
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Stuurman NF, Muller A, Conradie J. Conformational analysis of triphenylphosphine in square planar [Rh(β-diketonato)(CO)(PPh3)] complexes. Crystal structure of [Rh(PhCOCHCO(CH2)3CH3)(CO)(PPh3)]. Inorganica Chim Acta 2013. [DOI: 10.1016/j.ica.2012.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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19
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Benincori T, Bonometti V, Cirilli R, Mussini PR, Marchesi A, Pierini M, Pilati T, Rizzo S, Sannicolò F. Steric and Electronic Effects on the Configurational Stability of Residual Chiral Phosphorus-Centered Three-Bladed Propellers: Tris-aryl Phosphane Oxides. Chemistry 2012; 19:165-81. [DOI: 10.1002/chem.201201180] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Revised: 08/02/2012] [Indexed: 11/06/2022]
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20
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Young PG, Jolliffe KA. Selective recognition of sulfate ions by tripodal cyclic peptides functionalised with (thio)urea binding sites. Org Biomol Chem 2012; 10:2664-72. [DOI: 10.1039/c2ob06964d] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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21
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Conradie J. Conformational analysis of triphenylphosphine in square planar organometallic complexes: [(PPh3)(ML1L2L3)] and [M(acac)(L′)(PPh3)]. Dalton Trans 2012; 41:10633-42. [DOI: 10.1039/c2dt30850a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Haberhauer G, Ernst S, Wilch C. An Unexpected and Easy Way of Freezing the Configuration of a Triaryl Phosphane Oxide. Chemistry 2011; 17:8643-7. [DOI: 10.1002/chem.201002073] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Revised: 02/21/2011] [Indexed: 11/09/2022]
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23
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Butler SJ, Jolliffe KA, Lee WYG, McDonough MJ, Reynolds AJ. Synthesis of backbone modified cyclic peptides bearing dipicolylamino sidearms. Tetrahedron 2011. [DOI: 10.1016/j.tet.2010.11.100] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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24
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Young PG, Clegg JK, Bhadbhade M, Jolliffe KA. Hybrid cyclic peptide–thiourea cryptands for anion recognition. Chem Commun (Camb) 2011; 47:463-5. [DOI: 10.1039/c0cc02223c] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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25
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Hopmann KH, Stuurman NF, Muller A, Conradie J. Substitution and Isomerization of Asymmetric β-Diketonato Rhodium(I) Complexes: A Crystallographic and Computational Study. Organometallics 2010. [DOI: 10.1021/om1000138] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kathrin H. Hopmann
- Center for Theoretical and Computational Chemistry and Department of Chemistry, University of Tromsø, N-9037 Tromsø, Norway
| | | | - Alfred Muller
- Department of Chemistry, University of Johannesburg (APK Campus), P.O. Box 524, Aucklandpark, Johannesburg 2006, Republic of South Africa
| | - Jeanet Conradie
- Center for Theoretical and Computational Chemistry and Department of Chemistry, University of Tromsø, N-9037 Tromsø, Norway
- Department of Chemistry, University of the Free State, 9300 Bloemfontein, Republic of South Africa
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26
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Schiemenz GP. The impact of ion pair association upon the 1H NMR spectra of cationic complexes akin to Grubbs catalysts. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2010; 48:261-269. [PMID: 20157902 DOI: 10.1002/mrc.2570] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A reconsideration of the (1)H NMR spectra of cationic transition metal complexes exhibiting the features of cyclophanes on the basis of Mislow's classification of topic groups arrives at the conclusion that the spectral changes triggered by chiral counterions reflect an intracationic diastereotopication of enantiotopic protons rather than the existence of pairs of long-lived diastereomeric ion pairs.
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Sanz-Cervera JF, Blasco R, Piera J, Cynamon M, Ibáñez I, Murguía M, Fustero S. Solution versus fluorous versus solid-phase synthesis of 2,5-disubstituted 1,3-azoles. Preliminary antibacterial activity studies. J Org Chem 2010; 74:8988-96. [PMID: 19894729 DOI: 10.1021/jo9016265] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A small library of compounds with an oxa(thia)zole scaffold and structural diversity in both positions 2 and 5 has been synthesized. Double acylation of a protected glycine affords intermediate alpha-amido-beta-ketoesters, which in turn can be dehydrated to afford 1,3-oxazoles or reacted with Lawesson's reagent to furnish 1,3-thiazoles. This procedure was designed with its adaptation to fluorous techniques in mind. Thus, when a protected glycine with a fluorous tag in the ester moiety is used as a starting material, the synthesis can be easily completed without column chromatography purification of intermediate compounds with good to excellent yields, thus affording a suitable entry to the preparation of small libraries of these bioactive compounds. The prepared oxa(thia)zoles were assayed for their antibacterial activity, and several of them were active against Staphylococcus aureus.
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Affiliation(s)
- Juan F Sanz-Cervera
- Departamento de Química Orgánica, Universidad de Valencia, 46100 Burjassot, Spain.
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Assignment of absolute configurations of chiral phospholene oxides by UV/CD spectroscopy using TD-DFT quantum chemical calculations and singular value decomposition approach for the analysis of the spectra. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.theochem.2009.04.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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29
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30
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Reetz MT, Guo H, Ma JA, Goddard R, Mynott RJ. Helical Triskelion Monophosphites as Ligands in Asymmetric Catalysis. J Am Chem Soc 2009; 131:4136-42. [DOI: 10.1021/ja809297a] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Manfred T. Reetz
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Hongchao Guo
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Jun-An Ma
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Richard Goddard
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Richard J. Mynott
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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Benincori T, Marchesi A, Pilati T, Ponti A, Rizzo S, Sannicolò F. Chirality in the absence of rigid stereogenic elements: the design of configurationally stable C3-symmetric propellers. Chemistry 2009; 15:94-105. [PMID: 19072792 DOI: 10.1002/chem.200801505] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Residual stereoisomerism is a form of stereoisomerism scarcely considered so far for applicative purposes, though extremely interesting, since the production of stereoisomers does not involve classical rigid stereogenic elements. In three-bladed propeller-shaped molecules, a preferred stereomerization mechanism, related to the correlated rotation of the rings, allows the free interconversion of stereoisomers inside separated sets (the residual stereoisomers) that can interconvert through higher energy pathways. In light of possible future applications as chiral ligands for transition metals in stereoselective processes, some C(3)-symmetric phosphorus-centered propellers, which could exist as residual enantiomers, are synthesized and the possibility of resolving their racemates into residual antipodes is explored. While the tris(aryl)methanes are configurationally stable at room temperature, only selected tris(aryl)phosphane oxides display a configurational stability high enough to allow resolution by HPLC on a chiral stationary phase (CSP HPLC) at a semipreparative level at room temperature. Stability was evaluated through different techniques (circular dichroism (CD) signal decay, dynamic CSP HPLC (CSP DHPLC), dynamic NMR analysis (DNMR)) and the results compared and discussed. Phosphanes were found much less stable than the corresponding phosphane oxides, for which preliminary calculations suggest that the three-ring-flip enantiomerization mechanism (M(0)) would be easier than phosphorus pyramidal inversion. The parameters affecting the configurational stability of the residual enantiomers of C(3)-symmetric propellers are discussed.
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Affiliation(s)
- Tiziana Benincori
- Dipartimento di Scienze Chimiche ed Ambientali, Università dell'Insubria via Valleggio 11, 22100 Como, Italy
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Zwijnenburg MA, Sousa C, Sokol AA, Bromley ST. Optical excitations of defects in realistic nanoscale silica clusters: Comparing the performance of density functional theory using hybrid functionals with correlated wavefunction methods. J Chem Phys 2008; 129:014706. [DOI: 10.1063/1.2943147] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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Haberhauer G. Steuerung planarer Chiralität – der Bau eines Kupferionen-betriebenen chiralen molekularen Scharniers. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200800062] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Haberhauer G. Control of Planar Chirality: The Construction of a Copper-Ion-Controlled Chiral Molecular Hinge. Angew Chem Int Ed Engl 2008; 47:3635-8. [DOI: 10.1002/anie.200800062] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Haberhauer G, Drosdow E, Oeser T, Rominger F. Structural investigation of westiellamide analogues. Tetrahedron 2008. [DOI: 10.1016/j.tet.2007.11.098] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Amino functionalized silica nanotube for base catalyzed reaction. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s0167-2991(08)80073-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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