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Call A, Capocasa G, Palone A, Vicens L, Aparicio E, Choukairi Afailal N, Siakavaras N, López Saló ME, Bietti M, Costas M. Highly Enantioselective Catalytic Lactonization at Nonactivated Primary and Secondary γ-C-H Bonds. J Am Chem Soc 2023; 145:18094-18103. [PMID: 37540636 PMCID: PMC10507665 DOI: 10.1021/jacs.3c06231] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Indexed: 08/06/2023]
Abstract
Chiral oxygenated aliphatic moieties are recurrent in biological and pharmaceutically relevant molecules and constitute one of the most versatile types of functionalities for further elaboration. Herein we report a protocol for straightforward and general access to chiral γ-lactones via enantioselective oxidation of strong nonactivated primary and secondary C(sp3)-H bonds in readily available carboxylic acids. The key enabling aspect is the use of robust sterically encumbered manganese catalysts that provide outstanding enantioselectivities (up to >99.9%) and yields (up to 96%) employing hydrogen peroxide as the oxidant. The resulting γ-lactones are of immediate interest for the preparation of inter alia natural products and recyclable polymeric materials.
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Affiliation(s)
- Arnau Call
- Institut
de Química Computacional i Catàlisi (IQCC) and Departament
de Química, Universitat de Girona, Campus Montilivi, Girona E-17071, Catalonia, Spain
| | - Giorgio Capocasa
- Institut
de Química Computacional i Catàlisi (IQCC) and Departament
de Química, Universitat de Girona, Campus Montilivi, Girona E-17071, Catalonia, Spain
| | - Andrea Palone
- Institut
de Química Computacional i Catàlisi (IQCC) and Departament
de Química, Universitat de Girona, Campus Montilivi, Girona E-17071, Catalonia, Spain
| | - Laia Vicens
- Institut
de Química Computacional i Catàlisi (IQCC) and Departament
de Química, Universitat de Girona, Campus Montilivi, Girona E-17071, Catalonia, Spain
| | - Eric Aparicio
- Institut
de Química Computacional i Catàlisi (IQCC) and Departament
de Química, Universitat de Girona, Campus Montilivi, Girona E-17071, Catalonia, Spain
| | - Najoua Choukairi Afailal
- Institut
de Química Computacional i Catàlisi (IQCC) and Departament
de Química, Universitat de Girona, Campus Montilivi, Girona E-17071, Catalonia, Spain
| | - Nikos Siakavaras
- Institut
de Química Computacional i Catàlisi (IQCC) and Departament
de Química, Universitat de Girona, Campus Montilivi, Girona E-17071, Catalonia, Spain
| | - Maria Eugènia López Saló
- Institut
de Química Computacional i Catàlisi (IQCC) and Departament
de Química, Universitat de Girona, Campus Montilivi, Girona E-17071, Catalonia, Spain
| | - Massimo Bietti
- Dipartimento
di Scienze e Tecnologie Chimiche, Università
“Tor Vergata”, Via della Ricerca Scientifica, 1 I-00133 Rome, Italy
| | - Miquel Costas
- Institut
de Química Computacional i Catàlisi (IQCC) and Departament
de Química, Universitat de Girona, Campus Montilivi, Girona E-17071, Catalonia, Spain
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2
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Heisig J, Heise NV, Hoenke S, Ströhl D, Csuk R. The Finally Rewarding Search for A Cytotoxic Isosteviol Derivative. Molecules 2023; 28:4951. [PMID: 37446613 DOI: 10.3390/molecules28134951] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/20/2023] [Accepted: 06/21/2023] [Indexed: 07/15/2023] Open
Abstract
Acid hydrolysis of stevioside resulted in a 63% yield of isosteviol (1), which served as a starting material for the preparation of numerous amides. These compounds were tested for cytotoxic activity, employing a panel of human tumor cell lines, and almost all amides were found to be non-cytotoxic. Only the combination of isosteviol, a (homo)-piperazinyl spacer and rhodamine B or rhodamine 101 unit proved to be particularly suitable. These spacered rhodamine conjugates exhibited cytotoxic activity in the sub-micromolar concentration range. In this regard, the homopiperazinyl-spacered derivatives were found to be better than those compounds with piperazinyl spacers, and rhodamine 101 conjugates were more cytotoxic than rhodamine B hybrids.
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Affiliation(s)
- Julia Heisig
- Organic Chemistry, Martin-Luther University Halle-Wittenberg, Kurt-Mothes, Str. 2, D-06120 Halle (Saale), Germany
| | - Niels V Heise
- Organic Chemistry, Martin-Luther University Halle-Wittenberg, Kurt-Mothes, Str. 2, D-06120 Halle (Saale), Germany
| | - Sophie Hoenke
- Organic Chemistry, Martin-Luther University Halle-Wittenberg, Kurt-Mothes, Str. 2, D-06120 Halle (Saale), Germany
| | - Dieter Ströhl
- Organic Chemistry, Martin-Luther University Halle-Wittenberg, Kurt-Mothes, Str. 2, D-06120 Halle (Saale), Germany
| | - René Csuk
- Organic Chemistry, Martin-Luther University Halle-Wittenberg, Kurt-Mothes, Str. 2, D-06120 Halle (Saale), Germany
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3
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Goldstein EL, Takada H, Sumii Y, Baba K, Stoltz BM. Synthesis of enantioenriched 2,2-disubstituted pyrrolidines via sequential asymmetric allylic alkylation and ring contraction. Tetrahedron 2022; 123:132940. [PMID: 36968983 PMCID: PMC10038171 DOI: 10.1016/j.tet.2022.132940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The synthesis of a variety of enantioenriched 2,2-disubstituted pyrrolidines is described. A stereogenic quaternary center is first formed utilizing an asymmetric allylic alkylation reaction of a benzyloxy imide, which can then be reduced to a chiral hydroxamic acid. This compound can then undergo a thermal "Spino" ring contraction to afford a carbamate protected 2,2-disubstituted pyrrolidine stereospecifically. These pyrrolidines can be further advanced to enantioenriched indolizidine compounds. This reaction sequence allows access to new molecules that could be useful in the development of pharmaceutical agents.
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Affiliation(s)
- Elizabeth L Goldstein
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Hirokazu Takada
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Yuji Sumii
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Katsuaki Baba
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Brian M Stoltz
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
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4
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Cao YX, Silalai P, Liu CF, Yu KY, Bao X, Zhao XH, Saeeng R, Fan CA. Hypervalent-Iodine(III)-Mediated Tandem Oxidative Dearomatization/Aziridination of Phenolic Amines: Synthesis of Functionalized Unactivated Aziridines. Chemistry 2021; 27:8473-8478. [PMID: 33844345 DOI: 10.1002/chem.202100762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Indexed: 11/11/2022]
Abstract
A new hypervalent-iodine(III)-mediated tandem reaction involving oxidative dearomatization and in situ aziridination of phenolic amines is described, providing a mild and effective method for the assembly of structurally interesting and synthetically useful aziridines. Importantly, the densely functionalized aziridines resulting from this unprecedented tandem reaction offer a platform for expeditious access to architecturally diverse aza-heterocycles through transformations initiated by selective ring-opening of aziridines.
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Affiliation(s)
- Ye-Xing Cao
- State Key Laboratory of Applied OrganicChemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou, 730000, P. R. China
| | - Patamawadee Silalai
- Department of Chemistry and Center for Innovation in Chemistry, Faculty of Science, Burapha University, Chonburi, 20131, Thailand
| | - Chun-Fang Liu
- State Key Laboratory of Applied OrganicChemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou, 730000, P. R. China
| | - Ke-Yin Yu
- State Key Laboratory of Applied OrganicChemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou, 730000, P. R. China
| | - Xu Bao
- State Key Laboratory of Applied OrganicChemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou, 730000, P. R. China
| | - Xian-He Zhao
- State Key Laboratory of Applied OrganicChemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou, 730000, P. R. China
| | - Rungnapha Saeeng
- Department of Chemistry and Center for Innovation in Chemistry, Faculty of Science, Burapha University, Chonburi, 20131, Thailand
| | - Chun-An Fan
- State Key Laboratory of Applied OrganicChemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou, 730000, P. R. China
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5
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Yu ZL, Cheng YF, Jiang NC, Wang J, Fan LW, Yuan Y, Li ZL, Gu QS, Liu XY. Desymmetrization of unactivated bis-alkenes via chiral Brønsted acid-catalysed hydroamination. Chem Sci 2020; 11:5987-5993. [PMID: 34094089 PMCID: PMC8159283 DOI: 10.1039/d0sc00001a] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Although great success has been achieved in catalytic asymmetric hydroamination of unactivated alkenes using transition metal catalysis and organocatalysis, the development of catalytic desymmetrising hydroamination of such alkenes remains a tough challenge in terms of attaining a high level of stereocontrol over both remote sites and reaction centers at the same time. To address this problem, here we report a highly efficient and practical desymmetrising hydroamination of unactivated alkenes catalysed by chiral Brønsted acids with both high diastereoselectivity and enantioselectivity. This method features a remarkably broad alkene scope, ranging from mono-substituted and gem-/1,2-disubstituted to the challenging tri- and tetra-substituted alkenes, to provide access to a variety of diversely functionalized chiral pyrrolidines bearing two congested tertiary or quaternary stereocenters with excellent efficiency under mild and user-friendly synthetic conditions. The key to success is indirect activation of unactivated alkenes by chiral Brønsted acids via a concerted hydroamination mechanism.
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Affiliation(s)
- Zhang-Long Yu
- Shenzhen Grubbs Institute, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology Shenzhen 518055 China
| | - Yong-Feng Cheng
- Shenzhen Grubbs Institute, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology Shenzhen 518055 China
| | - Na-Chuan Jiang
- Shenzhen Grubbs Institute, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology Shenzhen 518055 China
| | - Jian Wang
- Shenzhen Grubbs Institute, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology Shenzhen 518055 China
| | - Li-Wen Fan
- Shenzhen Grubbs Institute, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology Shenzhen 518055 China
| | - Yue Yuan
- Shenzhen Grubbs Institute, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology Shenzhen 518055 China
| | - Zhong-Liang Li
- Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology Shenzhen 518055 China
| | - Qiang-Shuai Gu
- Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology Shenzhen 518055 China .,Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Department of Chemistry, Southern University of Science and Technology Shenzhen 518055 China
| | - Xin-Yuan Liu
- Shenzhen Grubbs Institute, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology Shenzhen 518055 China
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6
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Holth TAD, Walters MA, Hutt OE, Georg GI. Diversity-Oriented Library Synthesis from Steviol and Isosteviol-Derived Scaffolds. ACS COMBINATORIAL SCIENCE 2020; 22:150-155. [PMID: 32065745 DOI: 10.1021/acscombsci.9b00186] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The readily available natural product stevioside provides a unique diterpene core structure that can be explored for small molecule library development by diversity-oriented synthesis and functional group transformations. Validation arrays were prepared from steviol, isosteviol, and related analogues, derived from stevioside, to produce over 90 compounds. These compounds were submitted to the NIH Molecular Libraries Small Molecule Repository for screening in the Molecular Libraries Screening Center Network. Micromolar hits were identified in multiple high-throughput assays for several library members. A cheminformatics analysis of the compounds was performed that verified the expected diversity and complexity of this set of compounds. The screening results indicate that scaffolds-derived natural products can provide screening hits against multiple target proteins.
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Affiliation(s)
- Trinh A. D. Holth
- Department of Medicinal Chemistry and Institute for Therapeutics Discovery and Development, College of Pharmacy, University of Minnesota, 717 Delaware Street Southeast, Minneapolis, Minnesota 55414, United States
| | - Michael A. Walters
- Department of Medicinal Chemistry and Institute for Therapeutics Discovery and Development, College of Pharmacy, University of Minnesota, 717 Delaware Street Southeast, Minneapolis, Minnesota 55414, United States
| | - Oliver E. Hutt
- Department of Medicinal Chemistry and Institute for Therapeutics Discovery and Development, College of Pharmacy, University of Minnesota, 717 Delaware Street Southeast, Minneapolis, Minnesota 55414, United States
| | - Gunda I. Georg
- Department of Medicinal Chemistry and Institute for Therapeutics Discovery and Development, College of Pharmacy, University of Minnesota, 717 Delaware Street Southeast, Minneapolis, Minnesota 55414, United States
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7
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Wein LA, Wurst K, Angyal P, Weisheit L, Magauer T. Synthesis of (-)-Mitrephorone A via a Bioinspired Late Stage C-H Oxidation of (-)-Mitrephorone B. J Am Chem Soc 2019; 141:19589-19593. [PMID: 31770485 DOI: 10.1021/jacs.9b11646] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We present a bioinspired late-stage C-H oxidation of the ent-trachylobane natural product mitrephorone B to mitrephorone A. The realization of this unprecedented transformation was accomplished by either an iron-catalyzed or electrochemical oxidation and enabled access to the densely substituted oxetane in one step. Formation of mitrephorone C, which is lacking the central oxetane unit but features a keto-function at C2, was not formed under these conditions.
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Affiliation(s)
- Lukas Anton Wein
- Institute of Organic Chemistry and Center for Molecular Biosciences , Leopold-Franzens-University Innsbruck , Innrain 80-82 , 6020 Innsbruck , Austria
| | - Klaus Wurst
- Institute of General, Inorganic and Theoretical Chemistry , Leopold-Franzens-University Innsbruck , Innrain 80-82 , 6020 Innsbruck , Austria
| | - Peter Angyal
- Institute of Organic Chemistry , Research Centre for Natural Sciences , Magyar tudósok körútja 2 , 1117 Budapest , Hungary
| | - Lara Weisheit
- Institute of Organic Chemistry and Center for Molecular Biosciences , Leopold-Franzens-University Innsbruck , Innrain 80-82 , 6020 Innsbruck , Austria
| | - Thomas Magauer
- Institute of Organic Chemistry and Center for Molecular Biosciences , Leopold-Franzens-University Innsbruck , Innrain 80-82 , 6020 Innsbruck , Austria
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8
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Chen P, Zhang D, Li M, Wu Q, Lam YPY, Guo Y, Chen C, Bai N, Malhotra S, Li W, O'Connor PB, Fu H. Discovery of novel, potent, isosteviol-based antithrombotic agents. Eur J Med Chem 2019; 183:111722. [PMID: 31563807 DOI: 10.1016/j.ejmech.2019.111722] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 12/24/2022]
Abstract
Thrombosis is a pathological coagulation process and can lead to many serious thrombotic diseases. Here, we report a novel potent antithrombotic compound (6k) based on isosteviol with anticoagulant and antiplatelet activities. 6k selectively inhibited FXa (Ki = 0.015 μM) against a panel of serine proteases and showed excellent anticoagulant activity (significant prolongation of ex vivo PT and aPTT over the vehicle, p < 0.01). 6k also significantly inhibited ADP-induced platelet aggregation in rats relative to the vehicle (p < 0.01). Furthermore, 6k exhibited potent ex vivo and in vivo antithrombotic activity in rats relative to the vehicle (p < 0.01 and p < 0.0001, respectively). Novel structure 6k, with potent antithrombotic activity, is expected to lead a promising approach for the development of antithrombotic agents.
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Affiliation(s)
- Peng Chen
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, No.38 Xueyuan Road, Haidian District, Beijing, 100191, China
| | - Dianwen Zhang
- Academy of Chinese Medical Sciences of Jilin Province, No.155 Chuangju Road, Changchun, 130012, China
| | - Meng Li
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
| | - Qiong Wu
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, No.38 Xueyuan Road, Haidian District, Beijing, 100191, China
| | - Yuko P Y Lam
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
| | - Yan Guo
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, No.38 Xueyuan Road, Haidian District, Beijing, 100191, China
| | - Chen Chen
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, No.38 Xueyuan Road, Haidian District, Beijing, 100191, China
| | - Nan Bai
- Program in Molecular Therapeutics, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA, 19111, United States; Department of Molecular Biosciences, University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS, 66045, United States
| | - Shipra Malhotra
- Program in Molecular Therapeutics, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA, 19111, United States; Center for Computational Biology, University of Kansas, 2030 Becker Drive, Lawrence, KS, 66047, United States
| | - Wei Li
- Academy of Chinese Medical Sciences of Jilin Province, No.155 Chuangju Road, Changchun, 130012, China
| | - Peter B O'Connor
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
| | - Hongzheng Fu
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, No.38 Xueyuan Road, Haidian District, Beijing, 100191, China.
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9
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Loizzi M, Miller DJ, Allemann RK. Silent catalytic promiscuity in the high-fidelity terpene cyclase δ-cadinene synthase. Org Biomol Chem 2019; 17:1206-1214. [PMID: 30652178 PMCID: PMC6369673 DOI: 10.1039/c8ob02821d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aza-analogues of carbocations inhibit δ-cadinene synthase: 1,6-cyclisation.
δ-Cadinene synthase (DCS) is a high-fidelity sesquiterpene synthase that generates δ-cadinene as the sole detectable organic product from its natural substrate (E,E)-FDP. Previous work with this enzyme using substrate analogues revealed the ability of DCS to catalyse both 1,10- and 1,6-cyclisations of substrate analogues. To test whether this apparent promiscuity was an artefact of alternate substrate use or an inherent property of the enzyme, aza analogues of the proposed α-bisabolyl cation intermediate were prepared since this cation would be formed after an initial 1,6-cyclisation of FDP. In the presence of 250 μM inorganic disphosphate both (R)- and (S)-aza-bisaboyl cations were potent competitive inhibitors of DCS (Ki = 2.5 ± 0.5 mM and 3.44 ± 1.43 μM, respectively). These compounds were also shown to be potent inhibitors of the 1,6-cyclase amorpha-4,11-diene synthase but not of the 1,10-cyclase aristolochene synthase from Penicillium roquefortii, demonstrating that the 1,6-cyclase activity of DCS is most likely an inherent property of the enzyme even when the natural substrate is used and not an artefact of the use of substrate analogues.
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Affiliation(s)
- Marianna Loizzi
- School of Chemistry, Cardiff University Main Building, Park Place, Cardiff, CF10 3AT, UK.
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10
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Farndon JJ, Young TA, Bower JF. Stereospecific Alkene Aziridination Using a Bifunctional Amino-Reagent: An Aza-Prilezhaev Reaction. J Am Chem Soc 2018; 140:17846-17850. [DOI: 10.1021/jacs.8b10485] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Joshua J. Farndon
- School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
| | - Tom A. Young
- School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
| | - John F. Bower
- School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
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11
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Murillo JA, Gil JF, Upegui YA, Restrepo AM, Robledo SM, Quiñones W, Echeverri F, San Martin A, Olivo HF, Escobar G. Antileishmanial activity and cytotoxicity of ent-beyerene diterpenoids. Bioorg Med Chem 2018; 27:153-160. [PMID: 30482546 DOI: 10.1016/j.bmc.2018.11.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 11/08/2018] [Accepted: 11/20/2018] [Indexed: 02/08/2023]
Abstract
We describe the in vitro activity of two natural isomeric ent-beyerene diterpenes, several derivatives and synthetic intermediates. Beyerenols 1 and 2 showed EC50 of 4.6 ± 9.4 and 5.3 ± 9.4 μg/mL against amastigotes of L. (V) brazilensis, with SI of 5.1 and 7.7, respectively. Beyerenol 1 was synthesized from stevioside. In vivo experiments with bereyenols showed cure in 50% of hamsters infected with L. (V) brazilensis topically applied as Cream I (beyerenol 1, 0.81%, w/w) and Cream III (beyerenol 2, 1.96%, w/w). These results suggest that beyerenols are potential candidates for cutaneous leishmaniasis chemotherapy by topical application. In vitro assays of amastigotes of L. (V) brazilensis showed EC50 of 1.1 ± 0.1 and 1.3 ± 0.04 μg/mL, with SI of 3.1 and 3.5 for hydrazone intermediates 10 and 11, respectively.
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Affiliation(s)
- Jilmar A Murillo
- QOPN Grupo Química Orgánica de Productos Naturales, Instituto de Química, Universidad de Antioquia, Medellín, Colombia
| | - Juan F Gil
- QOPN Grupo Química Orgánica de Productos Naturales, Instituto de Química, Universidad de Antioquia, Medellín, Colombia
| | - Yulieth A Upegui
- PECET, Instituto de Investigaciones Médicas, Facultad de Medicina, Universidad de Antioquia, Calle 70 No. 52-21, Postal Code 0500100, Medellín, Colombia
| | - Adriana M Restrepo
- PECET, Instituto de Investigaciones Médicas, Facultad de Medicina, Universidad de Antioquia, Calle 70 No. 52-21, Postal Code 0500100, Medellín, Colombia
| | - Sara M Robledo
- PECET, Instituto de Investigaciones Médicas, Facultad de Medicina, Universidad de Antioquia, Calle 70 No. 52-21, Postal Code 0500100, Medellín, Colombia
| | - Winston Quiñones
- QOPN Grupo Química Orgánica de Productos Naturales, Instituto de Química, Universidad de Antioquia, Medellín, Colombia
| | - Fernando Echeverri
- QOPN Grupo Química Orgánica de Productos Naturales, Instituto de Química, Universidad de Antioquia, Medellín, Colombia
| | | | - Horacio F Olivo
- Division of Medicinal and Natural Products Chemistry, The University of Iowa, Iowa City, IA 52242, USA
| | - Gustavo Escobar
- QOPN Grupo Química Orgánica de Productos Naturales, Instituto de Química, Universidad de Antioquia, Medellín, Colombia.
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12
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Revathi L, Ravindar L, Fang WY, Rakesh KP, Qin HL. Visible Light-Induced C−H Bond Functionalization: A Critical Review. Adv Synth Catal 2018. [DOI: 10.1002/adsc.201800736] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Lekkala Revathi
- State Key Laboratory of Silicate Materials for Architectures; and School of Chemistry, Chemical Engineering and Life Science; Wuhan University of Technology; 205 Luoshi Road Wuhan, Hubei Province 430070 People's Republic of China
| | - Lekkala Ravindar
- State Key Laboratory of Silicate Materials for Architectures; and School of Chemistry, Chemical Engineering and Life Science; Wuhan University of Technology; 205 Luoshi Road Wuhan, Hubei Province 430070 People's Republic of China
| | - Wan-Yin Fang
- State Key Laboratory of Silicate Materials for Architectures; and School of Chemistry, Chemical Engineering and Life Science; Wuhan University of Technology; 205 Luoshi Road Wuhan, Hubei Province 430070 People's Republic of China
| | - K. P. Rakesh
- State Key Laboratory of Silicate Materials for Architectures; and School of Chemistry, Chemical Engineering and Life Science; Wuhan University of Technology; 205 Luoshi Road Wuhan, Hubei Province 430070 People's Republic of China
| | - Hua-Li Qin
- State Key Laboratory of Silicate Materials for Architectures; and School of Chemistry, Chemical Engineering and Life Science; Wuhan University of Technology; 205 Luoshi Road Wuhan, Hubei Province 430070 People's Republic of China
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13
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Wang M, Li H, Xu F, Gao X, Li J, Xu S, Zhang D, Wu X, Xu J, Hua H, Li D. Diterpenoid lead stevioside and its hydrolysis products steviol and isosteviol: Biological activity and structural modification. Eur J Med Chem 2018; 156:885-906. [DOI: 10.1016/j.ejmech.2018.07.052] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Revised: 07/19/2018] [Accepted: 07/21/2018] [Indexed: 12/17/2022]
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14
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Hanson JR. Skeletal Rearrangements of Rings C and D of the Kaurene and Beyerene Tetracyclic Diterpenoids. JOURNAL OF CHEMICAL RESEARCH 2018. [DOI: 10.3184/174751918x15233039624478] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The skeletal rearrangement of the bicyclo[3.2.1]octane portion of rings C and D of the kaurene and beyerene tetracyclic diterpenoids are reviewed, revealing the tendency of the secondary carbocations to rearrange to tertiary carbocations with the eventual preferential formation of bicyclo[2.2.2]octanes. Under acid-catalysed conditions the variations in the products with the nucleophilicity of the counter ions suggest that the intervention of discrete rather than completely delocalised non-classical carbonium ions may be contributing to the reaction pathway.
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Affiliation(s)
- James R. Hanson
- Department of Chemistry, University of Sussex, Brighton, Sussex BN1 9QJ, UK
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15
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16
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Fu L, Lin QX, Onyango EO, Liby KT, Sporn MB, Gribble GW. Design, synthesis, and biological activity of second-generation synthetic oleanane triterpenoids. Org Biomol Chem 2017; 15:6001-6005. [DOI: 10.1039/c7ob01420a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Synthetic manipulation of oleanolic acid affords a novel and biologically active C-24 demethylated CDDO-Me.
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Affiliation(s)
- Liangfeng Fu
- Department of Chemistry
- Dartmouth College
- Hanover
- USA
| | - Qi-xian Lin
- Department of Chemistry
- Dartmouth College
- Hanover
- USA
| | | | - Karen T. Liby
- Department of Pharmacology and Toxicology
- Geisel School of Medicine
- Hanover
- USA
| | - Michael B. Sporn
- Department of Pharmacology and Toxicology
- Geisel School of Medicine
- Hanover
- USA
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17
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Alizadeh A, Bagherinejad A, Bayat F, Zhu LG. One-pot regio- and chemo-selective synthesis of thiaazatricyclododecane. Tetrahedron 2016. [DOI: 10.1016/j.tet.2016.09.049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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18
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Ghorbani M, Mohammadi B, Saraii M, Masoumi B, Abbasian M, Ramazani A, Slepokura K, Lis T. A Three-Component Reaction for the Synthesis of 1-Azabicyclo[3.1.0]hexane-3-enes. Org Lett 2016; 18:4759-4761. [PMID: 27617698 DOI: 10.1021/acs.orglett.6b02180] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A novel and simple synthesis of 1-azabicyclo[3.1.0]hexane-3-ene derivatives is described. The synthesis is carried out via a simple three-component reaction between aryl aldehydes, malononitrile, and hydroxylamine hydrochloride in water. Eco-friendliness, excellent product yields, short reaction time, inexpensive and readily available starting materials, and interesting reaction and products are the main advantages of this method.
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Affiliation(s)
- Mahdi Ghorbani
- Department of Chemistry, Payame Noor University , P.O. Box 19395-3697, Tehran, Iran
| | - Bagher Mohammadi
- Department of Chemistry, Payame Noor University , P.O. Box 19395-3697, Tehran, Iran
| | - Mahnaz Saraii
- Department of Chemistry, Payame Noor University , P.O. Box 19395-3697, Tehran, Iran
| | - Bakhshali Masoumi
- Department of Chemistry, Payame Noor University , P.O. Box 19395-3697, Tehran, Iran
| | - Mojtaba Abbasian
- Department of Chemistry, Payame Noor University , P.O. Box 19395-3697, Tehran, Iran
| | - Ali Ramazani
- Department of Chemistry, University of Zanjan , P. O. Box 45195-313, Zanjan, Iran
| | - Katarzyna Slepokura
- Faculty of Chemistry, University of Wrocław , 14 Joliot-Curie St., 50-383 Wrocław, Poland
| | - Tadeusz Lis
- Faculty of Chemistry, University of Wrocław , 14 Joliot-Curie St., 50-383 Wrocław, Poland
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19
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References. Antibiotics (Basel) 2015. [DOI: 10.1128/9781555819316.refs] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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20
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Yamada K, Okada M, Fukuyama T, Ravelli D, Fagnoni M, Ryu I. Photocatalyzed site-selective C-H to C-C conversion of aliphatic nitriles. Org Lett 2015; 17:1292-5. [PMID: 25692554 DOI: 10.1021/acs.orglett.5b00282] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
β- or γ-Site-selective C-H alkylation of aliphatic nitriles has been achieved using a decatungstate salt as the photocatalyst. The observed site selectivity was justified by a radical polar effect in transition states for hydrogen abstraction.
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Affiliation(s)
- Keiichi Yamada
- Department of Chemistry, Graduate School of Science, Osaka Prefecture University , Sakai, Osaka 599-8531, Japan
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21
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Hong YJ, Tantillo DJ. Viability of Nonclassical Carbocations Proposed as Intermediates in the Biosynthesis of Atiserene, Beyerene, Kaurene, and Trachylobane Diterpenes. Helv Chim Acta 2014. [DOI: 10.1002/hlca.201400082] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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22
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Khaybullin RN, Zhang M, Fu J, Liang X, Li T, Katritzky AR, Okunieff P, Qi X. Design and synthesis of isosteviol triazole conjugates for cancer therapy. Molecules 2014; 19:18676-89. [PMID: 25405286 PMCID: PMC5753759 DOI: 10.3390/molecules191118676] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 11/06/2014] [Accepted: 11/06/2014] [Indexed: 01/26/2023] Open
Abstract
One of the keys for successfully developing drugs against the broad spectrum of cancer cell types is structural diversity. In the current study, we focused on a family of isosteviol derivatives as potential novel antitumor agents. Isosteviol is a tetracyclic diterpenoid obtained by acid hydrolysis of steviol glycoside extracts isolated from abundant Stevia rebaudiana plants. In this work, we have designed and synthesized a panel of isosteviol triazole conjugates using "click" chemistry methodology. Evaluation of these compounds against a series of cancer cell lines derived from primary and metastatic tumors demonstrated that these conjugates exhibit cytotoxic activities with IC50 in the low μM range. In addition, their anti-proliferative activities are cancer cell type specific. Taken together, our studies underscore the importance of structural diversity in achieving cancer cell type specific drug development.
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Affiliation(s)
- Ravil N Khaybullin
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA
| | - Mei Zhang
- Department of Radiation Oncology, College of Medicine, University of Florida Health Cancer Center, Gainesville, FL 32610, USA
| | - Junjie Fu
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA
| | - Xiao Liang
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA
| | - Tammy Li
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA
| | - Alan R Katritzky
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Paul Okunieff
- Department of Radiation Oncology, College of Medicine, University of Florida Health Cancer Center, Gainesville, FL 32610, USA
| | - Xin Qi
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA.
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23
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Jackson AJ, Hershey DM, Chesnut T, Xu M, Peters RJ. Biochemical characterization of the castor bean ent-kaurene synthase(-like) family supports quantum chemical view of diterpene cyclization. PHYTOCHEMISTRY 2014; 103:13-21. [PMID: 24810014 PMCID: PMC4062354 DOI: 10.1016/j.phytochem.2014.04.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 04/04/2014] [Accepted: 04/10/2014] [Indexed: 05/20/2023]
Abstract
It has become apparent that plants have extensively diversified their arsenal of labdane-related diterpenoids (LRDs), in part via gene duplication and neo-functionalization of the ancestral ent-kaurene synthase (KS) required for gibberellin metabolism. For example, castor bean (Ricinus communis) was previously shown to produce an interesting set of biosynthetically related diterpenes, specifically ent-sandracopimaradiene, ent-beyerene, and ent-trachylobane, in addition to ent-kaurene, using four separate diterpene synthases, albeit these remain unidentified. Notably, despite mechanistic similarity of the underlying reaction to that catalyzed by KSs, ent-beyerene and ent-trachylobane synthases have not yet been identified. Given our interest in LRD biosynthesis, and the recent availability of the castor bean genome sequence, a synthetic biology approach was applied to biochemically characterize the four KS(-like) enzymes [KS(L)s] found in Ricinus communis [i.e., the RcKS(L)s]. In particular, using bacteria engineered to produce the relevant ent-copalyl diphosphate precursor and synthetic genes based on the predicted RcKS(L)s, although this ultimately required correction of a "splicing" error in one of the predicted genes, highlighting the dependence of such a synthetic biology approach on accurate gene sequences. Nevertheless, it is possible to assign each of the four RcKS(L)s to one of the previously observed diterpene synthase activities, providing access to functionally enzymes. Intriguingly, the product distribution of the RcKS(L)s seems to support the distinct diterpene synthase reaction mechanism proposed by quantum chemical calculations, rather than the classically proposed pathway.
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Affiliation(s)
- Alana J Jackson
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - David M Hershey
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Taylor Chesnut
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Meimei Xu
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Reuben J Peters
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA 50011, USA.
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24
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Zi J, Mafu S, Peters RJ. To gibberellins and beyond! Surveying the evolution of (di)terpenoid metabolism. ANNUAL REVIEW OF PLANT BIOLOGY 2014; 65:259-86. [PMID: 24471837 PMCID: PMC4118669 DOI: 10.1146/annurev-arplant-050213-035705] [Citation(s) in RCA: 180] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The diterpenoids are classically defined by their composition--four isoprenyl units (20 carbons)--and are generally derived from [E,E,E]-geranylgeranyl diphosphate (GGPP). Such metabolism seems to be ancient and has been extensively diversified, with ∼12,000 diterpenoid natural products known. Particularly notable are the gibberellin phytohormones, whose requisite biosynthesis has provided a genetic reservoir that gave rise to not only a large superfamily of ∼7,000 diterpenoids but also, to some degree, all plant terpenoid natural products. This review focuses on the diterpenoids, particularly the defining biosynthetic characteristics of the major superfamilies defined by the cyclization and/or rearrangement of GGPP catalyzed by diterpene synthases/cyclases, although it also includes some discussion of the important subsequent elaboration in the few cases where sufficient molecular genetic information is available. It additionally addresses the array of biological activity providing the selective pressures that drive the observed gene family expansion and diversification, along with biosynthetic gene clustering.
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25
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Isegawa M, Maeda S, Tantillo DJ, Morokuma K. Predicting pathways for terpene formation from first principles – routes to known and new sesquiterpenes. Chem Sci 2014. [DOI: 10.1039/c3sc53293c] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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26
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Lohoelter C, Brutschy M, Lubczyk D, Waldvogel SR. Novel supramolecular affinity materials based on (-)-isosteviol as molecular templates. Beilstein J Org Chem 2013; 9:2821-33. [PMID: 24367446 PMCID: PMC3869372 DOI: 10.3762/bjoc.9.317] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 11/07/2013] [Indexed: 01/20/2023] Open
Abstract
The readily available ex-chiral-pool building block (-)-isosteviol was combined with the C 3-symmetric platforms hexahydroxytriphenylene and hexaaminotriptycene providing large and rigid molecular architectures. Because of the persistent cavities these scaffolds are very potent supramolecular affinity materials for head space analysis by quartz crystal microbalances. The scaffolds serve in particular as templates for tracing air-borne arenes at low concentration. The affinities of the synthesized materials towards different air-borne arenes were determined by 200 MHz quartz crystal microbalances.
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Affiliation(s)
- Christina Lohoelter
- Institute for Organic Chemistry, Johannes Gutenberg University, Duesbergweg 10–14, 55128 Mainz, Germany
| | - Malte Brutschy
- Institute for Organic Chemistry, Johannes Gutenberg University, Duesbergweg 10–14, 55128 Mainz, Germany
| | - Daniel Lubczyk
- Institute for Organic Chemistry, Johannes Gutenberg University, Duesbergweg 10–14, 55128 Mainz, Germany
| | - Siegfried R Waldvogel
- Institute for Organic Chemistry, Johannes Gutenberg University, Duesbergweg 10–14, 55128 Mainz, Germany
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27
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Lohoelter C, Weckbecker M, Waldvogel SR. (-)-Isosteviol as a Versatile Ex-Chiral-Pool Building Block for Organic Chemistry. European J Org Chem 2013. [DOI: 10.1002/ejoc.201300447] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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28
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Mei RH, Liu ZG, Cheng H, Xu L, Wang FP. Synthesis of the 10-Azatricyclo[3.3.2.04,8]decane Core of C20-Diterpenoid Alkaloid Racemulsonine via Iodine(III) Promoted Transannular Aziridination Reaction. Org Lett 2013; 15:2206-9. [PMID: 23587046 DOI: 10.1021/ol400755x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ru-Huai Mei
- Key Laboratory of Drug Targeting, Ministry of Education, and Department of Chemistry of Medicinal Natural Products, West China College of Pharmacy, Sichuan University, No. 17, Duan 3, Renmin Nan Road, Chengdu 610041, P. R. China
| | - Zhi-Gang Liu
- Key Laboratory of Drug Targeting, Ministry of Education, and Department of Chemistry of Medicinal Natural Products, West China College of Pharmacy, Sichuan University, No. 17, Duan 3, Renmin Nan Road, Chengdu 610041, P. R. China
| | - Hang Cheng
- Key Laboratory of Drug Targeting, Ministry of Education, and Department of Chemistry of Medicinal Natural Products, West China College of Pharmacy, Sichuan University, No. 17, Duan 3, Renmin Nan Road, Chengdu 610041, P. R. China
| | - Liang Xu
- Key Laboratory of Drug Targeting, Ministry of Education, and Department of Chemistry of Medicinal Natural Products, West China College of Pharmacy, Sichuan University, No. 17, Duan 3, Renmin Nan Road, Chengdu 610041, P. R. China
| | - Feng-Peng Wang
- Key Laboratory of Drug Targeting, Ministry of Education, and Department of Chemistry of Medicinal Natural Products, West China College of Pharmacy, Sichuan University, No. 17, Duan 3, Renmin Nan Road, Chengdu 610041, P. R. China
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Hutt OE, Doan TL, Georg GI. Synthesis of skeletally diverse and stereochemically complex library templates derived from isosteviol and steviol. Org Lett 2013; 15:1602-5. [PMID: 23530630 PMCID: PMC3638842 DOI: 10.1021/ol400385w] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
We have applied a diversity-oriented approach for the synthesis of skeletally diverse and stereochemically complex templates for small-molecule library production by performing Beckmann rearrangement and Beckmann fragmentation reactions on the bicyclo[3.2.1]octane rings of steviol and isosteviol, aglycones derived from the diterpene natural product stevioside. The optimization of these two reaction pathways is presented along with the successful application of a photo-Beckmann rearrangement. This work also led to the discovery of cyano-Prins-type and Thorpe-Ziegler-type cyclization reactions.
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Affiliation(s)
- Oliver E Hutt
- Institute for Therapeutics Discovery and Development, Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, 717 Delaware Street SE, Minneapolis, Minnesota 55414, United States
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30
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Nguyen QNN, Tantillo DJ. Caryolene-forming carbocation rearrangements. Beilstein J Org Chem 2013; 9:323-31. [PMID: 23503674 PMCID: PMC3596059 DOI: 10.3762/bjoc.9.37] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 01/21/2013] [Indexed: 11/23/2022] Open
Abstract
Density functional theory calculations on mechanisms of the formation of caryolene, a putative biosynthetic precursor to caryol-1(11)-en-10-ol, reveal two mechanisms for caryolene formation: one involves a base-catalyzed deprotonation/reprotonation sequence and tertiary carbocation minimum, whereas the other (with a higher energy barrier) involves intramolecular proton transfer and the generation of a secondary carbocation minimum and a hydrogen-bridged minimum. Both mechanisms are predicted to involve concerted suprafacial/suprafacial [2 + 2] cycloadditions, whose asynchronicity allows them to avoid the constraints of orbital symmetry.
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Affiliation(s)
- Quynh Nhu N Nguyen
- Department of Chemistry, University of California-Davis, 1 Shields Avenue, Davis, CA 95616, USA
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31
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Major DT, Weitman M. Electrostatically guided dynamics--the root of fidelity in a promiscuous terpene synthase? J Am Chem Soc 2012; 134:19454-62. [PMID: 23101787 DOI: 10.1021/ja308295p] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Terpene cyclases are responsible for the initial cyclization cascade in the multistep synthesis of more than 60,000 known natural products. This abundance of compounds is generated using a very limited pool of substrates based on linear isoprenoids. The astounding chemodiversity obtained by terpene cyclases suggests a tremendous catalytic challenge to these often promiscuous enzymes. In the current study we present a detailed mechanistic view of the biosynthesis of the monoterpene bornyl diphosphate (BPP) from geranyl diphosphate by BPP synthase using state of the art simulation methods. We identify the bornyl cation as an enzyme-induced bifurcation point on the multidimensional free energy surface, connecting between the product BPP and the side product camphene. Chemical dynamics simulations suggest that the active site diphosphate moiety steers reaction trajectories toward product formation. Nonetheless, chemical dynamics is not precise enough for exclusive product formation, providing a rationale for the lack of fidelity in this promiscuous terpene cyclase.
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Affiliation(s)
- Dan Thomas Major
- Department of Chemistry and the Lise Meitner-Minerva Center of Computational Quantum Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel.
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32
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Khaybullin RN, Strobykina IY, Dobrynin AB, Gubaydullin AT, Chestnova RV, Babaev VM, Kataev VE. Synthesis and antituberculosis activity of novel unfolded and macrocyclic derivatives of ent-kaurane steviol. Bioorg Med Chem Lett 2012; 22:6909-13. [DOI: 10.1016/j.bmcl.2012.09.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 09/04/2012] [Accepted: 09/06/2012] [Indexed: 10/27/2022]
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33
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Lohoelter C, Schollmeyer D, Waldvogel SR. Derivatives of (-)-Isosteviol with Expanded Ring D and Various Oxygen Functionalities. European J Org Chem 2012. [DOI: 10.1002/ejoc.201200970] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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34
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Zhang T, Lu LH, Liu H, Wang JW, Wang RX, Zhang YX, Tao JC. D-ring modified novel isosteviol derivatives: Design, synthesis and cytotoxic activity evaluation. Bioorg Med Chem Lett 2012; 22:5827-32. [DOI: 10.1016/j.bmcl.2012.07.083] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 07/15/2012] [Accepted: 07/24/2012] [Indexed: 11/15/2022]
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35
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Wu Y, Wang X, Gong JH, Tao JC. Ethyl ent-15α-[(2-nitrobenzyloxy)methyl]-16-oxobeyeran-20-oate. Acta Crystallogr Sect E Struct Rep Online 2012; 68:o2342. [PMID: 22904810 PMCID: PMC3414277 DOI: 10.1107/s1600536812029418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 06/28/2012] [Indexed: 11/10/2022]
Abstract
In the title compound, C30H41NO6, the three six-membered rings adopt chair conformations and the stereochemistry of the A/B and B/C ring junctions are trans. The five-membered ring D adopts an envelope conformation, with the methylene C atom as the flap. The title compound was synthesized via esterification, Tollens reaction, 1,5-hydride shift from the natural tetracyclic diterpenoid isosteviol
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36
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Zu L, Xu M, Lodewyk MW, Cane DE, Peters RJ, Tantillo DJ. Effect of isotopically sensitive branching on product distribution for pentalenene synthase: support for a mechanism predicted by quantum chemistry. J Am Chem Soc 2012; 134:11369-71. [PMID: 22738258 DOI: 10.1021/ja3043245] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mechanistic proposals for the carbocation cascade reaction leading to the tricyclic sesquiterpene pentalenene are assessed in light of the results of isotopically sensitive branching experiments with the H309A mutant of pentalenene synthase. These experimental results support a mechanism for pentalenene formation involving a 7-protoilludyl cation whose intermediacy was first predicted using quantum-chemical calculations.
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Affiliation(s)
- Liansuo Zu
- Department of Chemistry, University of California, Davis, California 95616, USA
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37
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Faraldos JA, Miller DJ, González V, Yoosuf-Aly Z, Cascón O, Li A, Allemann RK. A 1,6-ring closure mechanism for (+)-δ-cadinene synthase? J Am Chem Soc 2012; 134:5900-8. [PMID: 22397618 DOI: 10.1021/ja211820p] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Recombinant (+)-δ-cadinene synthase (DCS) from Gossypium arboreum catalyzes the metal-dependent cyclization of (E,E)-farnesyl diphosphate (FDP) to the cadinane sesquiterpene δ-cadinene, the parent hydrocarbon of cotton phytoalexins such as gossypol. In contrast to some other sesquiterpene cyclases, DCS carries out this transformation with >98% fidelity but, as a consequence, leaves no mechanistic traces of its mode of action. The formation of (+)-δ-cadinene has been shown to occur via the enzyme-bound intermediate (3R)-nerolidyl diphosphate (NDP), which in turn has been postulated to be converted to cis-germacradienyl cation after a 1,10-cyclization. A subsequent 1,3-hydride shift would then relocate the carbocation within the transient macrocycle to expedite a second cyclization that yields the cadinenyl cation with the correct cis stereochemistry found in (+)-δ-cadinene. An elegant 1,10-mechanistic pathway that avoids the formation of (3R)-NDP has also been suggested. In this alternative scenario, the final cadinenyl cation is proposed to be formed through the intermediacy of trans, trans-germacradienyl cation and germacrene D. In addition, an alternative 1,6-ring closure mechanism via the bisabolyl cation has previously been envisioned. We report here a detailed investigation of the catalytic mechanism of DCS using a variety of mechanistic probes including, among others, deuterated and fluorinated FDPs. Farnesyl diphosphate analogues with fluorine at C2 and C10 acted as inhibitors of DCS, but intriguingly, after prolonged overnight incubations, they yielded 2F-germacrene(s) and a 10F-humulene, respectively. The observed 1,10-, and to a lesser extent, 1,11-cyclization activity of DCS with these fluorinated substrates is consistent with the postulated macrocyclization mechanism(s) en route to (+)-δ-cadinene. On the other hand, mechanistic results from incubations of DCS with 6F-FPP, (2Z,6E)-FDP, neryl diphosphate, 6,7-dihydro-FDP, and NDP seem to be in better agreement with the potential involvement of the alternative biosynthetic 1,6-ring closure pathway. In particular, the strong inhibition of DCS by 6F-FDP, coupled to the exclusive bisabolyl- and terpinyl-derived product profiles observed for the DCS-catalyzed turnover of (2Z,6E)-farnesyl and neryl diphosphates, suggested the intermediacy of α-bisabolyl cation. DCS incubations with enantiomerically pure [1-(2)H(1)](1R)-FDP revealed that the putative bisabolyl-derived 1,6-pathway proceeds through (3R)-nerolidyl diphosphate (NDP), is consistent with previous deuterium-labeling studies, and accounts for the cis stereochemistry characteristic of cadinenyl-derived sesquiterpenes. While the results reported here do not unambiguously rule in favor of 1,6- or 1,10-cyclization, they demonstrate the mechanistic versatility inherent to DCS and highlight the possible existence of multiple mechanistic pathways.
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Affiliation(s)
- Juan A Faraldos
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, United Kingdom
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Wu Y, Wang X, Gong JH, Wei CY, Tao JC. Ethyl ent-15α-[(2-methoxybenzyloxy)methyl]-16-oxobeyeran-20-oate. Acta Crystallogr Sect E Struct Rep Online 2012; 68:o495. [PMID: 22347097 PMCID: PMC3275241 DOI: 10.1107/s1600536812001833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Accepted: 01/15/2012] [Indexed: 11/11/2022]
Abstract
The title compound, C31H44O5, was synthesized from isosteviol (systematic name: ent-16-ketobeyeran-19-oic acid). In the molecule, the three six-membered rings adopt chair conformations and the stereochemistry of the A/B and B/C ring junctions are trans. The five-membered ring D adopts an envelope conformation with the methylene C atom as the flap.
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39
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Faraldos JA, Antonczak AK, González V, Fullerton R, Tippmann EM, Allemann RK. Probing eudesmane cation-π interactions in catalysis by aristolochene synthase with non-canonical amino acids. J Am Chem Soc 2011; 133:13906-9. [PMID: 21815676 DOI: 10.1021/ja205927u] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Stabilization of the reaction intermediate eudesmane cation (3) through interaction with Trp 334 during catalysis by aristolochene synthase from Penicillium roqueforti was investigated by site-directed incorporation of proteinogenic and non-canonical aromatic amino acids. The amount of germacrene A (2) generated by the mutant enzymes served as a measure of the stabilization of 3. 2 is a neutral intermediate, from which 3 is formed during PR-AS catalysis by protonation of the C6,C7 double bond. The replacement of Trp 334 with para-substituted phenylalanines of increasing electron-withdrawing properties led to a progressive accumulation of 2 that showed a good correlation with the interaction energies of simple cations such as Na(+) with substituted benzenes. These results provide compelling evidence for the stabilizing role played by Trp 334 in aristolochene synthase catalysis for the energetically demanding transformation of 2 to 3.
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Affiliation(s)
- Juan A Faraldos
- School of Chemistry, Cardiff University, Park Place, Cardiff, United Kingdom
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40
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Tantillo DJ. Biosynthesis via carbocations: theoretical studies on terpene formation. Nat Prod Rep 2011; 28:1035-53. [PMID: 21541432 DOI: 10.1039/c1np00006c] [Citation(s) in RCA: 271] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review describes applications of quantum chemical calculations in the field of terpene biosynthesis, with a focus on insights into the mechanisms of terpene-forming carbocation rearrangements arising from theoretical studies.
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41
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Faraldos JA, Allemann RK. Inhibition of (+)-aristolochene synthase with iminium salts resembling eudesmane cation. Org Lett 2011; 13:1202-5. [PMID: 21271717 DOI: 10.1021/ol2000843] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Trigonal iminium halides of (4aS,7S)-1,4a-dimethyl- and (4aS,7S)-4a-methyl-7-(prop-1-en-2-yl)-2,3,4,4a,5,6,7,8-octahydroquinolinium ions, aimed to mimic transition states associated with the aristolochene synthase-catalyzed cyclization of (-)-germacrene A to eudesmane cation, were evaluated under standard kinetic steady-state conditions. In the presence of inorganic diphosphate, these analogues were shown to competitively inhibit the enzyme, suggesting a stabilizing role for the diphosphate leaving group in this apparently endothermic transformation.
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Affiliation(s)
- Juan A Faraldos
- School of Chemistry, Cardiff University, Cardiff, United Kingdom
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42
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Hong YJ, Tantillo DJ. How Many Secondary Carbocations Are Involved in the Biosynthesis of Avermitilol? Org Lett 2011; 13:1294-7. [DOI: 10.1021/ol103079v] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Young J. Hong
- Department of Chemistry, University of California−Davis, One Shields Avenue, Davis, California 95616, United States
| | - Dean J. Tantillo
- Department of Chemistry, University of California−Davis, One Shields Avenue, Davis, California 95616, United States
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Zhou K, Peters RJ. Electrostatic effects on (di)terpene synthase product outcome. Chem Commun (Camb) 2011; 47:4074-80. [PMID: 21305070 DOI: 10.1039/c0cc02960b] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Terpene synthases catalyze complex reactions, often forming multiple chiral centers in cyclized olefin products from acyclic allylic diphosphate precursors, yet have been suggested to largely control their reactions via steric effects, serving as templates. However, recent results highlight electrostatic effects also exerted by these enzymes. Perhaps not surprisingly, the pyrophosphate co-product released in the initiating and rate-limiting chemical step provides an obvious counter-ion that may steer carbocation migration towards itself. This is emphasized by the striking effects of a recently uncovered single residue switch for diterpene synthase product outcome, whereby substitution of hydroxyl residues for particular aliphatic residues has been shown to be sufficient to "short-circuit" complex cyclization and/or rearrangement reactions, with the converse change further found to be sufficient to increase reaction complexity. The mechanistic hypothesis for the observed effects is hydroxyl dipole stabilization of the specific carbocation formed by initial cyclization, enabling deprotonation of this early intermediate, whereas the lack of such stabilization (i.e. in the presence of an aliphatic side chain) leads to carbocation migration towards the pyrophosphate co-product, resulting in a more complex reaction. This is further consistent with the greater synergy exhibited between pyrophosphate and aza-analogs of late, relative to early, stage carbocation intermediates, and crystallographic analysis of the monoterpene cyclase bornyl diphosphate synthase wherein mechanistically non-relevant counter-ion pairing between aza-analogs of early stage carbocation intermediates and pyrophosphate is observed. Thus, (di)terpene synthases seem to mediate specific reaction outcomes, at least in part, by providing electrostatic effects to counteract those exerted by the pyrophosphate co-product.
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Affiliation(s)
- Ke Zhou
- Department of Biochemistry, Biophysics, & Molecular Biology, Iowa State University, Ames, IA 50011, USA
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Koohang A, Bailey JL, Coates RM, Erickson HK, Owen D, Poulter CD. Enantioselective inhibition of squalene synthase by aziridine analogues of presqualene diphosphate. J Org Chem 2010; 75:4769-77. [PMID: 20545375 DOI: 10.1021/jo100718z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Squalene synthase catalyzes the conversion of two molecules of (E,E)-farnesyl diphosphate to squalene via the cyclopropylcarbinyl intermediate, presqualene diphosphate (PSPP). Since this novel reaction constitutes the first committed step in sterol biosynthesis, there has been considerable interest and research on the stereochemistry and mechanism of the process and in the design of selective inhibitors of the enzyme. This paper reports the synthesis and characterization of five racemic and two enantiopure aziridine analogues of PSPP and the evaluation of their potencies as inhibitors of recombinant yeast squalene synthase. The key aziridine-2-methanol intermediates (6-OH, 7-OH, and 8-OH) were obtained by N-alkylations or by an N-acylation-reduction sequence of (+/-)-, (2R,3S)-, and (2S,3R)-2,3-aziridinofarnesol (9-OH) protected as tert-butyldimethylsilyl ethers. S(N)2 displacements of the corresponding methanesulfonates with pyrophosphate and methanediphosphonate anions afforded aziridine 2-methyl diphosphates and methanediphosphonates bearing N-undecyl, N-bishomogeranyl, and N-(alpha-methylene)bishomogeranyl substituents as mimics for the 2,6,10-trimethylundeca-2,5,9-trienyl side chain of PSPP. The 2R,3S diphosphate enantiomer bearing the N-bishomogeranyl substituent corresponding in absolute stereochemistry to PSPP proved to be the most potent inhibitor (IC(50) 1.17 +/- 0.08 muM in the presence of inorganic pyrophosphate), a value 4-fold less than that of its 2S,3R stereoisomer. The other aziridine analogues bearing the N-(alpha-methylene)bishomogeranyl and N-undecyl substituents, and the related methanediphosphonates, exhibited lower affinities for recombinant squalene synthase.
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Affiliation(s)
- Ali Koohang
- Department of Chemistry, University of Illinois, 600 South Mathews Avenue, Urbana, Illinois 61801, USA
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Wu Y, Liu CJ, Liu X, Dai GF, Du JY, Tao JC. Stereoselective Synthesis, Characterization, and Antibacterial Activities of Novel Isosteviol Derivatives with D-Ring Modification. Helv Chim Acta 2010. [DOI: 10.1002/hlca.201000046] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Hong YJ, Tantillo DJ. Formation of Beyerene, Kaurene, Trachylobane, and Atiserene Diterpenes by Rearrangements That Avoid Secondary Carbocations. J Am Chem Soc 2010; 132:5375-86. [DOI: 10.1021/ja9084786] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Young J. Hong
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616
| | - Dean J. Tantillo
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616
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Faraldos JA, Kariuki B, Allemann RK. Intermediacy of Eudesmane Cation during Catalysis by Aristolochene Synthase. J Org Chem 2010; 75:1119-25. [DOI: 10.1021/jo902397v] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Juan A. Faraldos
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Benson Kariuki
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Rudolf K. Allemann
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
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Hong YJ, Tantillo DJ. Quantum chemical dissection of the classic terpinyl/pinyl/bornyl/camphyl cation conundrum—the role of pyrophosphate in manipulating pathways to monoterpenes. Org Biomol Chem 2010; 8:4589-600. [DOI: 10.1039/c0ob00167h] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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49
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First Example of Diterpenoids from 14,15-Cyclopimarane in the Roots of Linum usitatissimum. Helv Chim Acta 2009. [DOI: 10.1002/hlca.200900104] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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50
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Hu H, Faraldos JA, Coates RM. Scope and mechanism of intramolecular aziridination of cyclopent-3-enyl-methylamines to 1-azatricyclo[2.2.1.0(2,6)]heptanes with lead tetraacetate. J Am Chem Soc 2009; 131:11998-2006. [PMID: 19653649 PMCID: PMC2766562 DOI: 10.1021/ja9044136] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of seven cyclopent-3-en-1-ylmethylamines bearing one, two, or three methyl substituents at the C2, C3, C4, or C(alpha) positions, including the unsubstituted parent, was accessed by ring-closing metatheses of alpha,alpha-diallylacetonitrile (or methallyl variants) and alpha,alpha-diallylacetone followed by hydride reductions or reductive amination, or by Curtius degradations of alpha,alpha-dimethyl- and 2,2,3-trimethylcyclopent-3-enylacetic acids. Oxidation of the primary amines with Pb(OAc)(4) in CH(2)Cl(2), CHCl(3) or benzene in the presence of K(2)CO(3) effected efficient intramolecular aziridinations, in all cases except the alpha-methyl analogue (16), to form the corresponding 1-azatricyclo[2.2.1.0(2,6)]heptanes, including the novel monoterpene analogues, 1-azatricyclene and the 2-azatricyclene enantiomers. The cumulative rate increases of aziridination reactions observed by (1)H NMR spectroscopy in CDCl(3) resulting from the presence of one or two methyl groups on the cyclopentene double bond, in comparison to the rate of the unsubstituted parent amine (1:17.5:>280), indicate a highly electrophilic intermediate as the nitrene donor and a symmetrical aziridine-like transition state. A mechanism is outlined in which the amine displaces an acetate ligand from Pb(OAc)(4) to form a lead(IV) amide intermediate RNHPb(OAc)(3) proposed as the actual aziridinating species.
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Affiliation(s)
- Huayou Hu
- Department of Chemistry, University of Illinois, 600 South Mathews Avenue, Urbana, Illinois 61801, USA
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