1
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Lim SH, You H, Kim MJ, Wee KR, Cho DW. Triplet Energy Transfer (EnT)-Promoted 1,3-Dipolar Cycloaddition Reactions of N-(Trimethylsilyl)methylphthalimide with Electron-Deficient Alkynes and Alkenes. J Org Chem 2024; 89:13150-13166. [PMID: 39225314 DOI: 10.1021/acs.joc.4c01287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Triplet energy transfer (EnT)-promoted photochemical pathways, arisen by visible light and its photosensitizers, have gained significant attention as a complementary strategy for initiating organic transformations in photochemical reactions that are unlikely to occur through a single electron transfer (SET) process. In the present study, we investigated the triplet EnT-promoted 1,3-dipolar cycloaddition reactions of N-(trimethylsilyl)methylphthalimide with electron-deficient alkynyl and alkenyl dipolarophiles. The triplet excited state of N-(trimethylsilyl)methylphthalimide, promoted by the triplet EnT from thioxanthone (TXA) photosensitizer, underwent sequential intramolecular SET and carbon-to-oxygen migration of the silyl group to form azomethine ylide. This generated ylide cycloadded to alkynes or alkenes to regioselectively and stereospecifically produce a nitrogen-containing benzopyrrolizidine scaffold with multiple stereogenic centers. Crucially, the stereoselectivity of these cycloaddition reactions (i.e., endo versus exo addition) was influenced by the nature of the dipolarophiles.
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Affiliation(s)
- Suk Hyun Lim
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Republic of Korea
| | - Hayeon You
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Republic of Korea
| | - Min-Ji Kim
- Department of Advanced Materials Chemistry, Korea University, Sejong 30019, Republic of Korea
| | - Kyung-Ryang Wee
- Department of Advanced Materials Chemistry, Korea University, Sejong 30019, Republic of Korea
| | - Dae Won Cho
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Republic of Korea
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2
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Nutter M, Stone H, Shipman M, Roesner S. Stereoselective synthesis of ( R)- and ( S)-1,2-diazetidine-3-carboxylic acid derivatives for peptidomimetics. Org Biomol Chem 2024; 22:2974-2977. [PMID: 38533707 DOI: 10.1039/d4ob00278d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
The stereoselective synthesis of both enantiomers of N-protected 1,2-diazetidine-3-carboxylic acid (aAze) from homochiral glycidol is described. Orthogonal protection of this novel cyclic α-hydrazino acid allows for selective functionalisation at either Nγ or Nδ. This novel peptidomimetic building block was incorporated into the pseudotripeptides Gly-γaAze-Ala and Gly-δaAze-Ala.
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Affiliation(s)
- Matthew Nutter
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.
| | - Henry Stone
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.
| | - Michael Shipman
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.
| | - Stefan Roesner
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.
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3
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Balkenhohl M, Kölbl S, Georgiev T, Carreira EM. Mn- and Co-Catalyzed Aminocyclizations of Unsaturated Hydrazones Providing a Broad Range of Functionalized Pyrazolines. JACS AU 2021; 1:919-924. [PMID: 34337605 PMCID: PMC8317158 DOI: 10.1021/jacsau.1c00176] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Manganese- and cobalt-catalyzed aminocyclization reactions of unsaturated hydrazones are reported. Whereas manganese catalysis provides access to pyrazoline and tetrahydropyridazine alcohols, cobalt catalysis for the first time paves the way for the selective formation of pyrazoline aldehydes. Furthermore, various functional groups including hydroperoxide, thiol derivatives, iodide, and bicyclopentane may be introduced via manganese-catalyzed ring-forming aminofunctionalization. A progesterone receptor antagonist was prepared using the aminocyclization protocol.
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Affiliation(s)
- Moritz Balkenhohl
- Laboratorium für Organische
Chemie, Eidgenössische Technische
Hochschule Zürich, 8093 Zürich, Switzerland
| | - Sebastian Kölbl
- Laboratorium für Organische
Chemie, Eidgenössische Technische
Hochschule Zürich, 8093 Zürich, Switzerland
| | - Tony Georgiev
- Laboratorium für Organische
Chemie, Eidgenössische Technische
Hochschule Zürich, 8093 Zürich, Switzerland
| | - Erick M. Carreira
- Laboratorium für Organische
Chemie, Eidgenössische Technische
Hochschule Zürich, 8093 Zürich, Switzerland
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4
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Xue Z, Li Y, Luo S. Chiral Primary Amine-Catalyzed Divergent Coupling of α-Substituted Acrylaldehydes with α-Diazoesters. ACS Catal 2020. [DOI: 10.1021/acscatal.0c02405] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Zaikun Xue
- Key Laboratory for Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100490, China
| | - Yao Li
- Center of Basic Molecular Science, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Sanzhong Luo
- Key Laboratory for Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100490, China
- Center of Basic Molecular Science, Department of Chemistry, Tsinghua University, Beijing 100084, China
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5
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Liu J, Han J, Izawa K, Sato T, White S, Meanwell NA, Soloshonok VA. Cyclic tailor-made amino acids in the design of modern pharmaceuticals. Eur J Med Chem 2020; 208:112736. [PMID: 32966895 DOI: 10.1016/j.ejmech.2020.112736] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/03/2020] [Accepted: 08/04/2020] [Indexed: 12/15/2022]
Abstract
Tailor-made AAs are indispensable components of modern medicinal chemistry and are becoming increasingly prominent in new drugs. In fact, about 30% of small-molecule pharmaceuticals contain residues of tailor-made AAs or structurally related diamines and amino-alcohols. Cyclic tailor-made AAs present a particular value to rational structural design by virtue of their local conformational constraints and are widely used in lead optimization programs. The present review article highlights 34 compounds, all of which are derived from cyclic AAs, representing recently-approved, small-molecule pharmaceuticals as well as promising drug candidates currently in various phases of clinical study. For each compound, the discussion includes the discovery, therapeutic profile and optimized synthesis, with a focus on the preparation of cyclic tailor-made AA as the principal structural feature. The present review article is intended to serve as a reference source for organic, medicinal and process chemists along with other professionals working in the fields of drug design and pharmaceutical discovery.
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Affiliation(s)
- Jiang Liu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Jianlin Han
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Kunisuke Izawa
- Hamari Chemicals Ltd., 1-4-29 Kunijima, Higashi-Yodogawa-ku, Osaka, 533-0024, Japan.
| | - Tatsunori Sato
- Hamari Chemicals Ltd., 1-4-29 Kunijima, Higashi-Yodogawa-ku, Osaka, 533-0024, Japan
| | - Sarah White
- Oakwood Chemical, Inc, 730 Columbia Hwy. N, Estill, SC, 29918, USA
| | - Nicholas A Meanwell
- Department of Small Molecule Drug Discovery, Bristol Myers Squibb Research and Early Development, PO Box, 4000, Princeton, NJ, 08543 4000, United States
| | - Vadim A Soloshonok
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain; IKERBASQUE, Basque Foundation for Science, María Díaz de Haro 3, Plaza Bizkaia, 48013, Bilbao, Spain.
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6
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Elbatrawi YM, Pedretty KP, Giddings N, Woodcock HL, Del Valle JR. δ-Azaproline and Its Oxidized Variants. J Org Chem 2020; 85:4207-4219. [DOI: 10.1021/acs.joc.9b03384] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Yassin M. Elbatrawi
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Kyle P. Pedretty
- Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States
| | - Nicole Giddings
- Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States
| | - H. Lee Woodcock
- Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States
| | - Juan R. Del Valle
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
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7
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Itoh K, Sibi MP. Dibenzofuran-4,6-bis(oxazoline) (DBFOX). A novel trans-chelating bis(oxazoline) ligand for asymmetric reactions. Org Biomol Chem 2019; 16:5551-5565. [PMID: 29947634 DOI: 10.1039/c8ob01010b] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The trans-chelating bis(oxazoline) ligand (R,R)-4,6-dibenzofurandiyl-2,2'-bis(4-phenyloxazoline) [(R,R)-DBFOX/Ph] coordinates metal ions to give C2-symmetric complexes which effectively catalyze a variety of asymmetric reactions. (R,R)-DBFOX/Ph·Ni(ClO4)2·3H2O, whose crystal structure is octahedral with three aqua ligands, can be stored under air for several months without loss of catalytic activity and promotes highly enantioselective reactions even in the presence of excess amounts of water, alcohols, amines, and acids. The complex shows remarkable chiral amplification in asymmetric Diels-Alder (DA) reactions. This review focuses on enantioselective reactions catalyzed by (R,R)-DBFOX/Ph·metal complexes.
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Affiliation(s)
- Kennosuke Itoh
- Laboratory of Medicinal Chemistry, School of Pharmacy, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo, Japan.
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8
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Just D, Hernandez-Guerra D, Kritsch S, Pohl R, Císařová I, Jones PG, Mackman R, Bahador G, Jahn U. Lithium Chloride Catalyzed Asymmetric Domino Aza-Michael Addition/[3 + 2] Cycloaddition Reactions for the Synthesis of Spiro- and Bicyclic α,β,γ-Triamino Acid Derivatives. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800585] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- David Just
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences; Flemingovo nám. 2 166 10 Prague 6 Czech Republic
| | - Daniel Hernandez-Guerra
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences; Flemingovo nám. 2 166 10 Prague 6 Czech Republic
| | - Susanne Kritsch
- Fachbereich Chemie; Technische Universität Braunschweig; Hagenring 30 38106 Braunschweig Germany
| | - Radek Pohl
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences; Flemingovo nám. 2 166 10 Prague 6 Czech Republic
| | - Ivana Císařová
- Department of Inorganic Chemistry; Faculty of Science; Charles University; Hlavova 2030/8 128 43 Prague 2 Czech Republic
| | - Peter G. Jones
- Fachbereich Chemie; Technische Universität Braunschweig; Hagenring 30 38106 Braunschweig Germany
| | - Richard Mackman
- Gilead Sciences, Inc.; 333 Lakeside Drive 94404 Foster City CA USA
| | - Gina Bahador
- Gilead Sciences, Inc.; 333 Lakeside Drive 94404 Foster City CA USA
| | - Ullrich Jahn
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences; Flemingovo nám. 2 166 10 Prague 6 Czech Republic
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9
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Zhao P, Wu S, Ke C, Liu X, Feng X. Chiral Lewis acid-catalyzed enantioselective cyclopropanation and C-H insertion reactions of vinyl ketones with α-diazoesters. Chem Commun (Camb) 2018; 54:9837-9840. [PMID: 30109874 DOI: 10.1039/c8cc05420g] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Enantioselective cyclopropanation and C-H insertion reactions of α-substituted vinyl ketones with α-diazoesters have been accomplished using a N,N'-dioxide-scandium(iii) complex catalyst. Various tetrasubstituted cyclopropanes and E-enone derivatives bearing a chiral ester substituent were obtained simultaneously with good yields and excellent enantioselectivities.
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Affiliation(s)
- Peng Zhao
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, P. R. China.
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10
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Catalytic hydrogenation of 1 and 2-pyrazoline. Isolation of pyrazolidine and process schemes. REACTION KINETICS MECHANISMS AND CATALYSIS 2018. [DOI: 10.1007/s11144-018-1389-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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11
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Hashimoto T, Maruoka K. Recent advances of catalytic asymmetric 1,3-dipolar cycloadditions. Chem Rev 2015; 115:5366-412. [PMID: 25961125 DOI: 10.1021/cr5007182] [Citation(s) in RCA: 740] [Impact Index Per Article: 82.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Takuya Hashimoto
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Keiji Maruoka
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan
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12
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Lalwani KG, Aher RD, Sudalai A. Organocatalytic [4+1]-annulation approach for the synthesis of densely functionalized pyrazolidine carboxylates. RSC Adv 2015. [DOI: 10.1039/c5ra09583b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The present protocol provides optically active pyrazolidine carboxylates with derivatizable functional groups in high yields with excellent enantio- and diastereoselectivities.
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Affiliation(s)
- Komal G. Lalwani
- Chemical Engineering & Process Development Division
- CSIR-National Chemical Laboratory
- Pune
- India-411008
| | - Ravindra D. Aher
- Chemical Engineering & Process Development Division
- CSIR-National Chemical Laboratory
- Pune
- India-411008
| | - Arumugam Sudalai
- Chemical Engineering & Process Development Division
- CSIR-National Chemical Laboratory
- Pune
- India-411008
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13
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Kumar R, Turcaud S, Micouin L. The reaction of dimethylalkynylaluminum reagents with trimethylsilyldiazomethane: original reactivity leading to new α-silylated alkynyl hydrazones. Org Lett 2014; 16:6192-5. [PMID: 25402443 DOI: 10.1021/ol503113d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Trimethylsilyl (TMS) diazomethane does not react as a homologating reagent but as a C-electrophilic species with dimethylalkynylaluminum reagents. This unprecedented reactivity enables a simple access to unusual α-silylated alkynyl hydrazones.
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Affiliation(s)
- Rahul Kumar
- Laboratoire de Chimie et Biochimie et Pharmacologiques et Toxicologiques, UMR 8601 CNRS-Université Paris Descartes Faculté des Sciences Fondamentales et Biomédicales, 45 rue des Saints Pères, 75006 Paris, France
| | - Serge Turcaud
- Laboratoire de Chimie et Biochimie et Pharmacologiques et Toxicologiques, UMR 8601 CNRS-Université Paris Descartes Faculté des Sciences Fondamentales et Biomédicales, 45 rue des Saints Pères, 75006 Paris, France
| | - Laurent Micouin
- Laboratoire de Chimie et Biochimie et Pharmacologiques et Toxicologiques, UMR 8601 CNRS-Université Paris Descartes Faculté des Sciences Fondamentales et Biomédicales, 45 rue des Saints Pères, 75006 Paris, France
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14
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Karlsson S, Brånalt J, Ölwegård Halvarsson M, Bergman J. A One-Pot Asymmetric Synthesis of a N-Acylated 4,5-Dihydropyrazole, A Key Intermediate of Thrombin Inhibitor AZD8165. Org Process Res Dev 2014. [DOI: 10.1021/op500134e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Staffan Karlsson
- Medicinal Chemistry, Cardiovascular & Metabolic Diseases iMed, AstraZeneca R&D Mölndal, S-431 83 Mölndal, Sweden
| | - Jonas Brånalt
- Medicinal Chemistry, Cardiovascular & Metabolic Diseases iMed, AstraZeneca R&D Mölndal, S-431 83 Mölndal, Sweden
| | - Maria Ölwegård Halvarsson
- Medicinal Chemistry, Cardiovascular & Metabolic Diseases iMed, AstraZeneca R&D Mölndal, S-431 83 Mölndal, Sweden
| | - Joakim Bergman
- Medicinal Chemistry, Cardiovascular & Metabolic Diseases iMed, AstraZeneca R&D Mölndal, S-431 83 Mölndal, Sweden
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15
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Hashimoto T, Maruoka K. Development of Synthetic Transformations by Control of Acid-Catalyzed Reactions of Diazocarbonyl Compounds. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2013. [DOI: 10.1246/bcsj.20130164] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Takuya Hashimoto
- Department of Chemistry, Graduate School of Science, Kyoto University
| | - Keiji Maruoka
- Department of Chemistry, Graduate School of Science, Kyoto University
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16
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Davis LO. Recent Developments in the Synthesis and Applications of Pyrazolidines. A Review. ORG PREP PROCED INT 2013. [DOI: 10.1080/00304948.2013.834769] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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17
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Wong SSY, Brant MG, Barr C, Oliver AG, Wulff JE. Dipolar addition to cyclic vinyl sulfones leading to dual conformation tricycles. Beilstein J Org Chem 2013; 9:1419-25. [PMID: 23946837 PMCID: PMC3740686 DOI: 10.3762/bjoc.9.159] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 06/10/2013] [Indexed: 12/24/2022] Open
Abstract
Dipolar addition of cyclic azomethine imines with cyclic vinyl sulfones gave rise to functionalized tricycles that exhibited fluxional behavior in solution at room temperature. The scope of the synthetic methodology was explored, and the origin of the fluxional behavior was probed by NMR methods together with DFT calculations. This behavior was ultimately attributed to stereochemical inversion at one of two nitrogen centers embedded in the tricyclic framework. Two tetracycles were also synthesized, and the degree of signal-broadening in the NMR spectra was found to depend on the presence of substitution next to the inverting nitrogen center.
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Affiliation(s)
- Steven S Y Wong
- Department of Chemistry, University of Victoria, PO Box 3065 STN CSC, Victoria, BC, V8W 3V6, Canada
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18
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Facile synthesis of novel tetrasubstituted 1-pyrazolines from Baylis–Hillman adducts and acyl diazomethanes. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.05.041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Wang W, Simovic DD, Di M, Fieber L, Rein KS. Synthesis, receptor binding and activity of iso and azakainoids. Bioorg Med Chem Lett 2013; 23:1949-52. [PMID: 23481645 DOI: 10.1016/j.bmcl.2013.02.046] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 02/05/2013] [Accepted: 02/08/2013] [Indexed: 11/26/2022]
Abstract
Two syntheses for the production of an unsubstituted azakainoid are described. The 1,3-dipolar cycloaddition of diazomethane with trans-dibenzyl glutaconate yields a 1-pyrazoline, which may be reduced directly to the pyrazolidine. An unexpected trans-cis isomerization is observed during Hg/Al reduction of the 1-pyrazoline NN bond. Alternatively, when TMS diazomethane is used as the dipole, the resulting 2-pyrazoline obtained after desilylation may be reduced with NaCNBH3 to provide the trans azakainate analog exclusively. The synthesis of an unsubstituted isokainoid via Michael addition is also described. Glutamate receptor binding assays revealed that the azakaniod has a moderate affinity for unspecified glutamate receptors. Membrane depolarization of Aplysia neurons upon application of the azakainoid demonstrates that it is an ionotropic glutamate receptor agonist.
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Affiliation(s)
- Wentian Wang
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Str., Miami, FL 33199, USA
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20
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Bouvet S, Moreau X, Coeffard V, Greck C. Synthesis of Enantioenriched Aza-Proline Derivatives through Gold(I)-Catalyzed Cyclization of Chiral α-Hydrazino Esters. J Org Chem 2012; 78:427-37. [DOI: 10.1021/jo302320v] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Sébastien Bouvet
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles-St-Quentin-en-Yvelines, 45 Avenue des États-Unis, 78035 Versailles cedex, France
| | - Xavier Moreau
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles-St-Quentin-en-Yvelines, 45 Avenue des États-Unis, 78035 Versailles cedex, France
| | - Vincent Coeffard
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles-St-Quentin-en-Yvelines, 45 Avenue des États-Unis, 78035 Versailles cedex, France
| | - Christine Greck
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles-St-Quentin-en-Yvelines, 45 Avenue des États-Unis, 78035 Versailles cedex, France
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22
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Reddy DN, Thirupathi R, Tumminakatti S, Prabhakaran EN. A method for stabilizing the cis prolyl peptide bond: influence of an unusual n→π∗ interaction in 1,3-oxazine and 1,3-thiazine containing peptidomimetics. Tetrahedron Lett 2012. [DOI: 10.1016/j.tetlet.2012.06.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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23
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Deiana L, Zhao GL, Leijonmarck H, Sun J, Lehmann CW, Córdova A. Direct catalytic asymmetric synthesis of pyrazolidine derivatives. ChemistryOpen 2012; 1:134-9. [PMID: 24551501 PMCID: PMC3922451 DOI: 10.1002/open.201200015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Indexed: 11/25/2022] Open
Affiliation(s)
- Luca Deiana
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University 10691 Stockholm (Sweden) ; Berzelii Center EXSELENT on Porous Materials, Arrhenius Laboratory, Stockholm University 10691 Stockholm (Sweden)
| | - Gui-Ling Zhao
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University 10691 Stockholm (Sweden) ; Berzelii Center EXSELENT on Porous Materials, Arrhenius Laboratory, Stockholm University 10691 Stockholm (Sweden)
| | - Hans Leijonmarck
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University 10691 Stockholm (Sweden) ; Berzelii Center EXSELENT on Porous Materials, Arrhenius Laboratory, Stockholm University 10691 Stockholm (Sweden)
| | - Junliang Sun
- Department of Structural Chemistry, Arrhenius Laboratory, Stockholm University 10691 Stockholm (Sweden) ; Berzelii Center EXSELENT on Porous Materials, Arrhenius Laboratory, Stockholm University 10691 Stockholm (Sweden)
| | - Christian W Lehmann
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr (Germany)
| | - Armando Córdova
- Department of Natural Sciences, Engineering and Mathematics, Mid Sweden University 85170 Sundsvall (Sweden) E-mail: ; Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University 10691 Stockholm (Sweden) ; Berzelii Center EXSELENT on Porous Materials, Arrhenius Laboratory, Stockholm University 10691 Stockholm (Sweden)
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Kumar BS, Venkataramasubramanian V, Sudalai A. Organocatalytic Sequential α-Amination/Corey–Chaykovsky Reaction of Aldehydes: A High Yield Synthesis of 4-Hydroxypyrazolidine Derivatives. Org Lett 2012; 14:2468-71. [DOI: 10.1021/ol300739b] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- B. Senthil Kumar
- Chemical Engineering and Process Development Division, National Chemical Laboratory, Pashan Road, Pune-411 008, India
| | - V. Venkataramasubramanian
- Chemical Engineering and Process Development Division, National Chemical Laboratory, Pashan Road, Pune-411 008, India
| | - Arumugam Sudalai
- Chemical Engineering and Process Development Division, National Chemical Laboratory, Pashan Road, Pune-411 008, India
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25
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Yamazaki S, Maenaka Y, Fujinami K, Mikata Y. Triphenylphosphine-mediated reaction of dialkyl azodicarboxylate with activated alkenes leading to pyrazolines. RSC Adv 2012. [DOI: 10.1039/c2ra21249h] [Citation(s) in RCA: 11] [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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26
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Mahé O, Dez I, Levacher V, Brière JF. Enantioselective synthesis of bio-relevant 3,5-diaryl pyrazolines. Org Biomol Chem 2012; 10:3946-54. [DOI: 10.1039/c2ob25227a] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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27
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Campbell NR, Sun B, Singh RP, Deng L. Cinchona alkaloid catalyzed enantioselective amination of α,β-unsaturated ketones: an asymmetric approach to Δ 2-pyrazolines. Adv Synth Catal 2011; 353:3123-3128. [PMID: 23807876 DOI: 10.1002/adsc.201100447] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Δ2-Pyrazolines are of significant medicinal and synthetic interest due to their therapeutic properties and utility in the synthesis of 1,3-diamines, yet few asymmetric methods exist to prepare them. An unprecedented highly enantioselective organocatalytic synthesis of 2-pyrazolines was achieved through an asymmetric conjugate addition catalyzed by 9-epi-amino cinchona alkaloids followed by deprotection-cyclization, which furnished chiral 2-pyrazolines in 46-78% yield and 59-91% ee. This bifunctional catalytic methodology thus provides easy access to considerable range of optically active 3,5-dialkyl 2-pyrazolines.
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Affiliation(s)
- Nathaniel R Campbell
- Department of Chemistry, Brandeis University, 415 South St., Waltham, MA 02454-9110, USA
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28
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Ben Hamadi N, Msaddek M. The Swern Oxidation: First example of direct oxidation of 2-pyrazolines with “activated” DMSO. CR CHIM 2011. [DOI: 10.1016/j.crci.2011.05.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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29
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Maity P, Lepore SD. Catalytic Synthesis of Nonracemic Azaproline Derivatives by Cyclization of β-Alkynyl Hydrazines under Kinetic Resolution Conditions. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201101090] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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30
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Maity P, Lepore SD. Catalytic synthesis of nonracemic azaproline derivatives by cyclization of β-alkynyl hydrazines under kinetic resolution conditions. Angew Chem Int Ed Engl 2011; 50:8338-41. [PMID: 21766401 DOI: 10.1002/anie.201101090] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2011] [Revised: 06/29/2001] [Indexed: 11/12/2022]
Affiliation(s)
- Pradip Maity
- Department of Chemistry, Florida Atlantic University, Boca Raton, FL 33431, USA
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31
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Abstract
Azapeptides are peptide analogs in which one or more of the amino residues is replaced by a semicarbazide. This substitution of a nitrogen for the α-carbon center results in conformational restrictions, which bend the peptide about the aza-amino acid residue away from a linear geometry. The resulting azapeptide turn conformations have been observed by x-ray crystallography and spectroscopy, as well as predicted based on computational models. In biologically active peptide analogs, the aza-substitution has led to enhanced activity and selectivity as well as improved properties, such as prolonged duration of action and metabolic stability. In light of these characteristics, azapeptides have found important uses as receptor ligands, enzyme inhibitors, drugs, pro-drugs, probes and imaging agents. Recent improvements in synthetic methods for their procurement have ushered in a new era of azapeptide chemistry. This review aims to provide a historical look at the development of azapeptide science along with a focus on recent developments and perspectives on the future of this useful tool for medicinal chemistry.
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32
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Patil NT, Singh V. Synthesis of 1,3,5-trisubstituted pyrazolines via Zn(ii)-catalyzed double hydroamination of enynes with aryl hydrazines. Chem Commun (Camb) 2011; 47:11116-8. [DOI: 10.1039/c1cc14850h] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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33
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Jakob F, Herdtweck E, Bach T. Synthesis and Properties of Chiral Pyrazolidines Derived from (+)-Pulegone. Chemistry 2010; 16:7537-46. [PMID: 20496356 DOI: 10.1002/chem.201000219] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Florian Jakob
- Lehrstuhl für Organische Chemie 1, Technische Universität München, Lichtenbergstrasse 4, 85747 Garching, Germany
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Abstract
This critical review, which is relevant to researchers in synthetic organic chemistry, focuses on asymmetric 1,3-dipolar cycloadditions with acrylamides. The use of chiral acrylamides as dipolarophiles leads to high levels of stereocontrol, due to conformational constraint in the acrylamides. Employment of chiral tertiary acrylamides containing nitrogen heterocycles is particularly effective in controlling the stereoselectivity. Following a general overview of 1,3-dipolar cycloadditions, the main body of the review focuses on asymmetric 1,3-dipolar cycloadditions of acrylamides with nitrile oxides, nitrones, diazoalkanes and azomethine ylides, with particular emphasis on the rationale for the observed stereocontrol (215 references).
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Affiliation(s)
- Marie Kissane
- Department of Chemistry, Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
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36
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Voss E, Arrault A, Bodiguel J, Jamart-Grégoire B. Efficient synthesis of enantiomerically pure (S)-δ-azaproline starting from (R)-α-hydroxy-γ-butyrolactone via the Mitsunobu reaction. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.tetasy.2009.07.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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37
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Shu W, Yang Q, Jia G, Ma S. Studies on palladium-catalyzed enantioselective cyclization of 3,4-allenylic hydrazines with organic halides. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.09.049] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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38
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Duan PW, Chiu CC, Lee WD, Pan LS, Venkatesham U, Tzeng ZH, Chen K. On the scope of diastereoselective aziridination of various chiral auxiliaries derived N- and O-enones with N-aminophthalimide in the presence of lead tetraacetate. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.tetasy.2008.02.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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39
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Yang Q, Jiang X, Ma S. Highly diastereoselective palladium-catalyzed cyclizations of 3,4-allenylic hydrazines and organic halides -- highly stereoselective synthesis of optically active pyrazolidine derivatives and the prediction of the stereoselectivity. Chemistry 2008; 13:9310-6. [PMID: 17696188 DOI: 10.1002/chem.200700620] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Pyrazolidines containing two chiral centers, an interesting class of heterocyclic compounds possessing a range of biological activities, have been prepared highly diastereoselectively (up to 95:5) through asymmetric Pd(OAc)(2)-catalyzed cyclizations between the easy available optically active allenylic hydrazines and organic halides in THF in the presence of (R,R)-Bn-Box (L2) as the ligand. It was observed 1) that in most cases (3R,5S)-pyrazolidines were obtained in good yields with very high enantiopurities (>99%) and high diastereoselectivities (up to 95:5) in the presence of (R,R)-Bn-Box (L2), 2) that aryl halides containing electron-donating or -withdrawing groups, heteroaryl, and 1-alkenyl iodides are all suitable substrates for this diastereoselective cyclization, 3) that the absolute configurations of the newly formed chiral centers in the pyrazolidines depend on the structure of substrate 1, and 4) that the enantio- and diastereopurities of the trans-pyrazolidines are co-controlled by the chiralities of the chiral catalysts and the substrates. A model for prediction of the enantiopurities of the products and the diastereoselectivities of the reactions based on an HPLC study of the starting hydrazines and the products was established.
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Affiliation(s)
- Qing Yang
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
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40
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Cui SL, Wang J, Wang YG. Facile Access to Pyrazolines via Domino Reaction of the Huisgen Zwitterions with Aziridines. Org Lett 2007; 10:13-6. [DOI: 10.1021/ol7022888] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Sun-Liang Cui
- Department of Chemistry, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - Jing Wang
- Department of Chemistry, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - Yan-Guang Wang
- Department of Chemistry, Zhejiang University, Hangzhou 310027, People's Republic of China
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41
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Sibi MP, Stanley LM, Soeta T. Enantioselective 1,3-Dipolar Cycloadditions of Diazoacetates with Electron-Deficient Olefins. Org Lett 2007; 9:1553-6. [PMID: 17367154 DOI: 10.1021/ol070364x] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] A general strategy for highly enantioselective 1,3-dipolar cycloaddition of diazoesters to beta-substituted, alpha-substituted, and alpha,beta-disubstituted alpha,beta-unsaturated pyrazolidinone imides is described. Cycloadditions utilizing less reactive alpha,beta-disubstituted dipolarophiles require elevated reaction temperatures, but still provide the corresponding pyrazolines with excellent enantioselectivities. Finally, an efficient synthesis of (-)-manzacidin A employing this cycloaddition methodology as a key step is illustrated.
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Affiliation(s)
- Mukund P Sibi
- Department of Chemistry, North Dakota State University, Fargo, North Dakota 58105, USA.
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42
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Tran K, Leighton J. A Simple, Efficient, and Highly Enantioselective Synthesis of MS-153 Employing a Chiral Silane Lewis Acid-Promoted Acylhydrazone-Enol Ether [3+2] Cycloaddition. Adv Synth Catal 2006. [DOI: 10.1002/adsc.200600357] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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43
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44
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Lange UEW, Baucke D, Hornberger W, Mack H, Seitz W, Höffken HW. Orally active thrombin inhibitors. Part 2: Optimization of the P2-moiety. Bioorg Med Chem Lett 2006; 16:2648-53. [PMID: 16460939 DOI: 10.1016/j.bmcl.2006.01.046] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2005] [Revised: 01/09/2006] [Accepted: 01/09/2006] [Indexed: 11/23/2022]
Abstract
Synthesis and SAR of orally active thrombin inhibitors of the d-Phe-Pro-Arg type with focus on the P2-moiety are described. The unexpected increase in in vitro potency, oral bioavailability, and in vivo activity of inhibitors with dehydroproline as P2-isostere is discussed. Over a period of 24h the antithrombin activity of the most active inhibitors with IC(50)s in the nanomolar range was determined in dogs demonstrating high thrombin inhibitory activity in plasma and an appropriate duration of action after oral administration.
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Affiliation(s)
- Udo E W Lange
- Abbott GmbH & Co. KG, D-67061 Ludwigshafen, Germany.
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45
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Kano T, Hashimoto T, Maruoka K. Enantioselective 1,3-Dipolar Cycloaddition Reaction between Diazoacetates and α-Substituted Acroleins: Total Synthesis of Manzacidin A. J Am Chem Soc 2006; 128:2174-5. [PMID: 16478146 DOI: 10.1021/ja056851u] [Citation(s) in RCA: 145] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A titanium BINOLate catalyzed asymmetric 1,3-dipolar cycloaddition reaction between alpha-substituted acroleins and alkyl diazoacetates has been developed. With this methodology in hand, chiral 2-pyrazolines containing a quaternary stereogenic center were obtained in high to excellent enantioselectivities (up to 95% ee). The synthetic utility of the optically enriched 2-pyrazoline thus obtained was demonstrated in the short synthesis of manzacidin A.
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Affiliation(s)
- Taichi Kano
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan
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46
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Reduction of substituted spiro[cyclopropane-3-(1-pyrazolines)] to spiro[cyclopropane-3-pyrazolidines] and 1-(2-aminoethyl)cyclopropylamine derivatives. Russ Chem Bull 2005. [DOI: 10.1007/s11172-006-0156-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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47
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Ruano JLG, Peromingo MT, Alonso M, Fraile A, Martín MR, Tito A. 1,3-Dipolar Cycloadditions of Diazoalkanes to Activated Sulfoxides: Influence of Lewis Acids. J Org Chem 2005; 70:8942-7. [PMID: 16238331 DOI: 10.1021/jo051574v] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] The reactions of diazomethane and diazoethane with (S)-3-p-tolylsulfinylfuran-2(5H)-one (3) and its 4-methyl derivative (4) have been studied. The sulfinyl group was able to completely control the pi-facial selectivity of all these reactions, which decreased when the polarity of the solvent increased and could be inverted in the presence of Lewis acids, Yb(OTf)(3) being the most efficient catalyst. This behavior made possible the stereodivergent synthesis of diastereoisomeric pyrazolines in almost quantitative yields and de's higher than 98%. The endo/exo selectivity was also complete in reactions of 3 with diazoethane, whereas 4 afforded an easily separable 1:1 mixture of diastereoisomers. Steric factors accounts for the endo/exo selectivity, whereas electrostatic interactions must also be considered to explain the facial selectivity.
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Affiliation(s)
- José L García Ruano
- Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, Spain.
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48
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Shirakawa S, Lombardi PJ, Leighton JL. A Simple and General Chiral Silicon Lewis Acid for Asymmetric Synthesis: Highly Enantioselective [3 + 2] Acylhydrazone−Enol Ether Cycloadditions. J Am Chem Soc 2005; 127:9974-5. [PMID: 16011341 DOI: 10.1021/ja052307+] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A highly diastereo- and enantioselective [3 + 2] acylhydrazone-enol ether cycloaddition mediated by a simple chiral silane Lewis acid is described. The reactions are highly practical, as demonstrated by a larger scale (5 g of the hydrazone) reaction in which the product was obtained after recrystallization in 93% yield and 99% ee. Evidence for a stepwise mechanism and a model for the asymmetric induction are presented, as well.
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Affiliation(s)
- Seiji Shirakawa
- Department of Chemistry, Columbia University, New York, New York 10027, USA
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49
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Synthesis of 2-Pyrazoline-5-Carboxylic Acid Derivatives Using Trimethylsilyldiazomethane. B KOREAN CHEM SOC 2005. [DOI: 10.5012/bkcs.2005.26.3.467] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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50
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Ritter T, Kvaernø L, Werder M, Hauser H, Carreira EM. Heterocyclic ring scaffolds as small-molecule cholesterol absorption inhibitors. Org Biomol Chem 2005; 3:3514-23. [PMID: 16172689 DOI: 10.1039/b510100j] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Enantio- and diastereoselective syntheses of a substituted oxazolidinone, isoxazoline and pyrazoline as beta-lactam surrogates are described. The substituted heterocycles were designed to incorporate side chains closely resembling those found in the beta-lactam cholesterol absorption inhibitor ezetimibe (1). Additionally, the in vitro inhibitory efficacy of the novel compounds as cholesterol absorption inhibitors is reported using a brush border membrane vesicle assay.
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Affiliation(s)
- Tobias Ritter
- Laboratorium für Organische Chemie, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
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