1
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Irie Y, Yokoshima S. Total Synthesis of Putative Melognine. J Am Chem Soc 2024; 146:9526-9531. [PMID: 38546412 DOI: 10.1021/jacs.4c02086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Total synthesis of melognine was accomplished. A 10-membered cyclic alkyne was prepared via an intramolecular SN2 reaction of a nosylamide. Enyne metathesis of the cyclic alkyne under an atmosphere of ethylene afforded a 1,3-diene. Intramolecular cycloaddition of a nitrone and an azomethine ylide with the 1,3-diene moiety constructed the characteristic highly fused skeleton. Further transformation, including ring-closing metathesis, resulted in the synthesis of melognine, whose NMR spectra did not match the reported data. Close inspection of the spectra of melognine in the literature suggested that the structure of melognine might be identical with that of a known alkaloid, melodinine L.
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Affiliation(s)
- Yui Irie
- Graduate School of Pharmaceutical Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Satoshi Yokoshima
- Graduate School of Pharmaceutical Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
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2
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Suman P, Tomar K, Nishad CS, Banerjee B. Metal-free synthesis of carbamoylated dihydroquinolinones via cascade radical annulation of cinnamamides with oxamic acids. Org Biomol Chem 2024; 22:1821-1833. [PMID: 38332745 DOI: 10.1039/d3ob01856c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2024]
Abstract
We report a metal-free procedure for the sustainable synthesis of carbamoylated dihydroquinolinones via tandem addition-cyclization of carbamoyl radicals to cinnamamides. Readily accessible, non-toxic and inexpensive oxamic acids are used as carbamoyl radical precursors. This highly straightforward method provides a mild and environmentally friendly route showing good atom economy and excellent functional group tolerance to obtain diverse medicinally important carbamoylated dihydroquinolinones in one pot. The cascade cyclization is also modular and step-economical with a wide substrate scope and the products were obtained in good to excellent yields. Additionally, the tolerance to air and water, operational simplicity, low cost and scalability enhance the practical value of the proposed synthetic strategy. Preliminary mechanistic studies reveal that cheap and environment-friendly ammonium persulfate acts as a radical initiator in the cascade process and generates carbamoyl radicals from oxamic acids. The synthetic utility of this method is further demonstrated by late stage functionalization of drug molecules with good yields.
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Affiliation(s)
- Pallav Suman
- Department of Chemistry, Central University of Punjab, Bathinda-151401, India.
| | - Kirti Tomar
- Department of Chemistry, Central University of Punjab, Bathinda-151401, India.
| | | | - Biplab Banerjee
- Department of Chemistry, Central University of Punjab, Bathinda-151401, India.
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3
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Mani S, Raju R, Raghunathan R, Arumugam N, Almansour AI, Kumar RS, Perumal K. Environmentally friendly domino multicomponent strategy for the synthesis of pyrroloquinolinone hybrid heterocycles. RSC Adv 2022; 12:15440-15446. [PMID: 35685174 PMCID: PMC9131013 DOI: 10.1039/d2ra02851d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 05/13/2022] [Indexed: 11/21/2022] Open
Abstract
An efficient and elegant assembly of pyrene/aryl fused pyrrolo[2,3-b]quinolinone and pyrrolizino[3,2-b]quinolinone hybrid heterocycles was achieved via a domino multicomponent reaction strategy using a solid state melt reaction (SSMR) condition. The 1,3-dipole component was generated in situ from N-methylgylcine/l-proline and isatin, while the Baylis-Hillman adduct prepared from pyrene-1-carbaldehyde and various benzaldehydes is used as the dipolarophile. The domino protocol comprises 1,3-dipolar cycloaddition and a consequent double annulation reaction process. The advantages of this cascade protocol include environmentally friendly conditions, the avoidance of toxic organic solvents, simple work-up and good to excellent product yields.
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Affiliation(s)
- Suresh Mani
- Department of Organic Chemistry, University of Madras, Guindy Campus Chennai 600025 India
| | - Rajesh Raju
- Department of Organic Chemistry, University of Madras, Guindy Campus Chennai 600025 India
| | | | - Natarajan Arumugam
- Department of Chemistry, College of Science, King Saud University P. O. Box 2455 Riyadh 11451 Saudi Arabia
| | - Abdulrahman I Almansour
- Department of Chemistry, College of Science, King Saud University P. O. Box 2455 Riyadh 11451 Saudi Arabia
| | - Raju Suresh Kumar
- Department of Chemistry, College of Science, King Saud University P. O. Box 2455 Riyadh 11451 Saudi Arabia
| | - Karthikeyan Perumal
- Department of Chemistry and Biochemistry, The Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
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4
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Qu Y, Xu W, Zhang J, Liu Y, Li Y, Song H, Wang Q. Visible-Light-Mediated [2+2+1] Carbocyclization Reactions of 1,7-Enynes with Bromofluoroacetate to Form Fused Monofluorinated Cyclopenta[ c]quinolin-4-ones. J Org Chem 2020; 85:5379-5389. [PMID: 32200642 DOI: 10.1021/acs.joc.0c00087] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Herein, we describe a new protocol for photoinduced radical [2+2+1] carbocyclization reactions of 1,7-enynes with bromofluoroacetate. These reactions, which proceed via a cascade involving fluoroalkylation, 6-exo-dig and 5-endo-trig cyclizations, H-transfer step, and oxidative dehydrogenation, provide an efficient and general route to a variety of fused monofluorinated cyclopenta[c]quinolin-4-one derivatives.
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Affiliation(s)
- Yi Qu
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin 300071, People's Republic of China
| | - Wentao Xu
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin 300071, People's Republic of China
| | - Jingjing Zhang
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin 300071, People's Republic of China.,Tianjin Agricultural University, Tianjin 300384, People's Republic of China
| | - Yuxiu Liu
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin 300071, People's Republic of China
| | - Yongqiang Li
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin 300071, People's Republic of China
| | - Hongjian Song
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin 300071, People's Republic of China
| | - Qingmin Wang
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin 300071, People's Republic of China
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5
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Lee CW, Taylor BLH, Petrova GP, Patel A, Morokuma K, Houk KN, Stoltz BM. An Unexpected Ireland–Claisen Rearrangement Cascade During the Synthesis of the Tricyclic Core of Curcusone C: Mechanistic Elucidation by Trial-and-Error and Automatic Artificial Force-Induced Reaction (AFIR) Computations. J Am Chem Soc 2019; 141:6995-7004. [PMID: 30907087 DOI: 10.1021/jacs.9b01146] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Chung Whan Lee
- Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Buck L. H. Taylor
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| | - Galina P. Petrova
- Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan
| | - Ashay Patel
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| | - Keiji Morokuma
- Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan
| | - K. N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| | - Brian M. Stoltz
- Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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6
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Goli N, Kallepu S, Mainkar PS, Lakshmi JK, Chegondi R, Chandrasekhar S. Synthetic Strategy toward the Pentacyclic Core of Melodinus Alkaloids. J Org Chem 2018; 83:2244-2249. [DOI: 10.1021/acs.joc.7b03138] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Navya Goli
- Academy of Scientific and Innovative Research (AcSIR), New Delhi, India
| | | | | | | | - Rambabu Chegondi
- Academy of Scientific and Innovative Research (AcSIR), New Delhi, India
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7
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Tan FL, Hu M, Song RJ, Li JH. Metal-Free Annulation Cascades of 1,7-Enynes Using Di-tert
-butyl Peroxide as the Methyl Source towards the Synthesis of Polyheterocyclic Scaffolds. Adv Synth Catal 2017. [DOI: 10.1002/adsc.201700699] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Fang-Lin Tan
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle; Nanchang Hangkong University; Nanchang 330063 People's Republic of China
- State Key Laboratory of Chemo/Biosensing and Chemometrics; Hunan University; Changsha 410082 People's Republic of China
| | - Ming Hu
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle; Nanchang Hangkong University; Nanchang 330063 People's Republic of China
- State Key Laboratory of Chemo/Biosensing and Chemometrics; Hunan University; Changsha 410082 People's Republic of China
| | - Ren-Jie Song
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle; Nanchang Hangkong University; Nanchang 330063 People's Republic of China
| | - Jin-Heng Li
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle; Nanchang Hangkong University; Nanchang 330063 People's Republic of China
- State Key Laboratory of Chemo/Biosensing and Chemometrics; Hunan University; Changsha 410082 People's Republic of China
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8
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O'Connor NR, Wood JL, Stoltz BM. Synthetic Applications and Methodological Developments of Donor-Acceptor Cyclopropanes and Related Compounds. Isr J Chem 2016; 56:431-444. [PMID: 31118539 PMCID: PMC6527366 DOI: 10.1002/ijch.201500089] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Donor-acceptor cyclopropanes are convenient precursors to reactive and versatile 1,3-dipoles, and have found application in the synthesis of a variety of carbo- and heterocyclic scaffolds. This perspective review details our laboratory's use of donor-acceptor cyclopropanes as intermediates toward the total synthesis of various natural products. We also discuss our work in the development of novel cycloadditions and rearrangements of donor-acceptor cyclopropanes and aziridines, as well as an example of an aryne insertion proceeding via fragmentation of a transient donor-acceptor cyclobutane.
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Affiliation(s)
- Nicholas R O'Connor
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd, MC 101-20, Pasadena, CA 91125 (USA)
| | - John L Wood
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798 (USA)
| | - Brian M Stoltz
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd, MC 101-20, Pasadena, CA 91125 (USA)
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9
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Gao F, Yang C, Ma N, Gao GL, Li D, Xia W. Visible-Light-Mediated 1,7-Enyne Bicyclizations for Synthesis of Cyclopenta[c]quinolines and Benzo[j]phenanthridines. Org Lett 2016; 18:600-3. [DOI: 10.1021/acs.orglett.5b03662] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Fei Gao
- State Key Lab of Urban Water
Resource and Environment, Shenzhen Graduate School, Harbin Institute of Technology, Harbin 150080, China
| | - Chao Yang
- State Key Lab of Urban Water
Resource and Environment, Shenzhen Graduate School, Harbin Institute of Technology, Harbin 150080, China
| | - Na Ma
- State Key Lab of Urban Water
Resource and Environment, Shenzhen Graduate School, Harbin Institute of Technology, Harbin 150080, China
| | - Guo-Lin Gao
- State Key Lab of Urban Water
Resource and Environment, Shenzhen Graduate School, Harbin Institute of Technology, Harbin 150080, China
| | - Dazhi Li
- State Key Lab of Urban Water
Resource and Environment, Shenzhen Graduate School, Harbin Institute of Technology, Harbin 150080, China
| | - Wujiong Xia
- State Key Lab of Urban Water
Resource and Environment, Shenzhen Graduate School, Harbin Institute of Technology, Harbin 150080, China
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10
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Xiao JA, Xia PJ, Zhang XY, Chen XQ, Ou GC, Yang H. Amide-assisted intramolecular [3+2] annulation of cyclopropane ring-opening: a facile and diastereoselective access to the tricyclic core of (±)-scandine. Chem Commun (Camb) 2016; 52:2177-80. [DOI: 10.1039/c5cc07485a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The amide-linked intramolecular [3+2] annulation of cyclopropane ring-opening has been developed to rapidly and diastereoselectively install the tricyclic dihydroquinolinone core of (±)-scandine.
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Affiliation(s)
- Jun-An Xiao
- College of Chemistry and Chemical Engineering
- Central South University
- Changsha 410083
- P. R. China
| | - Peng-Ju Xia
- College of Chemistry and Chemical Engineering
- Central South University
- Changsha 410083
- P. R. China
| | - Xing-Yu Zhang
- Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in Hunan South/Department of Biology and Chemistry
- Hunan University of Science and Engineering
- Yongzhou
- P. R. China
| | - Xiao-Qing Chen
- College of Chemistry and Chemical Engineering
- Central South University
- Changsha 410083
- P. R. China
| | - Guang-Chuan Ou
- Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in Hunan South/Department of Biology and Chemistry
- Hunan University of Science and Engineering
- Yongzhou
- P. R. China
| | - Hua Yang
- College of Chemistry and Chemical Engineering
- Central South University
- Changsha 410083
- P. R. China
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11
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Zhang J, Yun ding YD, Huang XJ, Jiang RW, Wang Y, Sun PH, Fan RZ, Zhang XQ, Ye WC. Melohemsines A-I, melodinus-type alkaloids from Melodinus hemsleyanus. RSC Adv 2016. [DOI: 10.1039/c6ra16762d] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Melohemsines A-I (1–9) were obtained from Melodinus hemsleyanus. 1 is the first melodinus-type alkaloid possessing a 6/6/5/5/6/3 six ring skeleton system. 2 and 3 are the first natural melodinus-type alkaloids with a reduction of two carbon units at C-20.
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Affiliation(s)
- Jian Zhang
- Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632
| | - Yun ding Yun ding
- Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632
| | - Xiao-Jun Huang
- Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632
| | - Ren-Wang Jiang
- Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632
| | - Ying Wang
- Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632
| | - Ping-Hua Sun
- Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632
| | - Run-Zhu Fan
- Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632
| | - Xiao-Qi Zhang
- Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632
| | - Wen-Cai Ye
- Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632
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12
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Hu M, Fan JH, Liu Y, Ouyang XH, Song RJ, Li JH. Metal-Free Radical [2+2+1] Carbocyclization of Benzene-Linked 1,n-Enynes: Dual C(sp3)H Functionalization Adjacent to a Heteroatom. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201504603] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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13
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Hu M, Fan JH, Liu Y, Ouyang XH, Song RJ, Li JH. Metal-Free Radical [2+2+1] Carbocyclization of Benzene-Linked 1,n-Enynes: Dual C(sp3)H Functionalization Adjacent to a Heteroatom. Angew Chem Int Ed Engl 2015; 54:9577-80. [DOI: 10.1002/anie.201504603] [Citation(s) in RCA: 148] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Indexed: 01/18/2023]
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14
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Goldberg AFG, Craig RA, O'Connor NR, Stoltz BM. Highly functionalized donor-acceptor cyclopropanes applied toward the synthesis of the Melodinus alkaloids. Tetrahedron Lett 2015; 56:2983-2990. [PMID: 26120207 DOI: 10.1016/j.tetlet.2014.09.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A series of highly substituted vinylcyclopropanes were prepared and examined as reaction partners in a palladium-catalyzed (3 + 2) cycloaddition with nitrostyrenes. Described herein are our efforts to synthesize an elusive 1,1-divinylcyclopropane by several distinct approaches, and to apply surrogates of this fragment toward the synthesis of the Melodinus alkaloids.
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Affiliation(s)
- Alexander F G Goldberg
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Boulevard, MC 101-20, Pasadena, CA 91125, USA
| | - Robert A Craig
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Boulevard, MC 101-20, Pasadena, CA 91125, USA
| | - Nicholas R O'Connor
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Boulevard, MC 101-20, Pasadena, CA 91125, USA
| | - Brian M Stoltz
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Boulevard, MC 101-20, Pasadena, CA 91125, USA
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15
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Hong BC, Chen ZY, Chen WH, Sun HI, Lee GH. Traceless Solid-Phase Synthesis of Cyclopenta[c]quinolines and Cyclopenta[c]chromenes via Hetero [6+3] Cycloadditions of Fulvene. A Facile Approach to the 11-Heterosteroids Framework. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.200500028] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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16
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Kohn BL, Jarvo ER. Palladium-Catalyzed Annulation Reactions for Diastereoselective Cyclopentene Synthesis. Org Lett 2011; 13:4858-61. [DOI: 10.1021/ol2019423] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Benjamin L. Kohn
- Department of Chemistry, Univerisity of California-Irvine, 1102 Natural Sciences II, Irvine, California 92697-2025, United States
| | - Elizabeth R. Jarvo
- Department of Chemistry, Univerisity of California-Irvine, 1102 Natural Sciences II, Irvine, California 92697-2025, United States
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17
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Goldberg AFG, Stoltz BM. A palladium-catalyzed vinylcyclopropane (3+2) cycloaddition approach to the Melodinus alkaloids. Org Lett 2011; 13:4474-6. [PMID: 21786746 DOI: 10.1021/ol2017615] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A palladium-catalyzed (3+2) cycloaddition of a vinylcyclopropane and a β-nitrostyrene is employed to rapidly assemble the cyclopentane core of the Melodinus alkaloids. The ABCD ring system of the natural product family is prepared in six steps from commercially available materials.
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Affiliation(s)
- Alexander F G Goldberg
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, MC 101-20, Pasadena, California 91125, USA
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18
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Burrell AJM, Coldham I, Watson L, Oram N, Pilgram CD, Martin NG. Stereoselective formation of fused tricyclic amines from acyclic aldehydes by a cascade process involving condensation, cyclization, and dipolar cycloaddition. J Org Chem 2009; 74:2290-300. [PMID: 18998734 DOI: 10.1021/jo8019913] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The preparation of tricyclic amines from acyclic precursors is described using a cascade of tandem reactions involving condensation of an aldehyde with a primary amine, cyclization (with displacement of a halide), and then in situ deprotonation or decarboxylation to give an azomethine ylide or nitrone followed by intramolecular dipolar cycloaddition. The methodology is straightforward, and the aldehyde precursors are prepared easily and quickly in high yield using nitrile alkylations followed by DIBAL-H reduction. The relative ease of reaction of various substrates with different tether lengths between the aldehyde and the halide or dipolarophile has been studied. Several primary amines including simple amino acids such as glycine, alanine, and phenylalanine and derivatives such as glycine ethyl ester and also hydroxylamine have been investigated. High yields are obtained in the formation of different tricyclic ring sizes; the dipolar cycloaddition necessarily creates a five-membered ring, and we have investigated the formation of five- and six-membered rings for the other two new ring sizes. In all cases, yields are high (except when using glycine when the tether to the terminal alkene dipolarophile leads to a six-membered ring), and most efficient is the formation of the tricyclic product in which all five-membered rings are formed. Examples with an alkyne as the dipolarophile were also successful. In all the reactions studied, the products are formed with complete regioselectivity and remarkably with complete stereoselectivity. The key step involves the formation of three new rings and potentially up to four new stereocenters in a single transformation. The power of the chemistry was demonstrated by the synthesis of the core ring systems of the alkaloids (+/-)-scandine and (+/-)-myrioneurinol and the total syntheses of the alkaloids (+/-)-aspidospermine, (+/-)-quebrachamine, and (+/-)-aspidospermidine.
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Affiliation(s)
- Adam J M Burrell
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, UK
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19
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Denmark S, Cottell J. A Tandem, Nitroalkene Conjugate Addition/[3+2] Cycloaddition Approach to the Synthesis of the Pentacyclic Core of (±)-Scandine. Adv Synth Catal 2006. [DOI: 10.1002/adsc.200600301] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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21
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Nick A, Rali T, Sticher O. Biological screening of traditional medicinal plants from Papua New Guinea. JOURNAL OF ETHNOPHARMACOLOGY 1995; 49:147-156. [PMID: 8824740 DOI: 10.1016/0378-8741(95)01315-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Based on ethnopharmacological literature, 17 species of medicinal plants used in the traditional medicine in Papua New Guinea were collected. Extracts of different polarities were tested in a preliminary biological screening for their antimicrobial (Escherichia coli, Bacillus subtilis, Micrococcus luteus and Penicillium oxalicum) and molluscicidal activity against Biomphalaria glabrata as well as for their toxicity to brine shrimp. The pretreated plant extracts were also investigated for their ability to inhibit protein kinase C and tyrosine-specific protein kinase of epidermal growth factor receptor. Furthermore, all plants were screened for the presence of alkaloids.
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Affiliation(s)
- A Nick
- Department of Pharmacy, Swiss Federal Institute of Technology, Zürich
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Jones K, Wilkinson J, Ewin R. Intramolecular reactions using amide links: Aryl radical cyclisation of silylated acryloylanilides. Tetrahedron Lett 1994. [DOI: 10.1016/s0040-4039(00)78372-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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