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Sim DSY, Tang SY, Low YY, Lim SH, Kam TS. Vobasine, vincamine, voaphylline, tacaman, and iboga alkaloids from Tabernaemontana corymbosa. PHYTOCHEMISTRY 2022; 203:113384. [PMID: 36007666 DOI: 10.1016/j.phytochem.2022.113384] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/12/2022] [Accepted: 08/14/2022] [Indexed: 06/15/2023]
Abstract
Thirteen indole alkaloids comprising six vobasine/sarpagine, one vincamine, two voaphylline, two tacaman, one iboga, and one corynantheine alkaloid, were isolated from the leaf extract of Tabernaemontana corymbosa (sample from Taiping, Perak, Malaysia). The structures of these alkaloids were determined based on analysis of the spectroscopic data (NMR and MS), and in the case of vincarudine, the absolute configuration was established by ECD and X-ray diffraction analysis. Vobasidine E represents the first vobasine-type alkaloid characterized by a contracted ring C and loss of the ethylidene/ethyl side chain. A possible biogenetic pathway from a perivine precursor, which was also present in the leaf extract, is presented. Differences in the new alkaloid content between the present and previous sample of the same plant (occurring in a different location) are discussed.
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Affiliation(s)
- Dawn Su-Yin Sim
- Department of Chemistry, Faculty of Science, Universiti Malaya, Kuala Lumpur, 50603, Malaysia
| | - Sin-Yee Tang
- Department of Chemistry, Faculty of Science, Universiti Malaya, Kuala Lumpur, 50603, Malaysia
| | - Yun-Yee Low
- Department of Chemistry, Faculty of Science, Universiti Malaya, Kuala Lumpur, 50603, Malaysia
| | - Siew-Huah Lim
- Department of Chemistry, Faculty of Science, Universiti Malaya, Kuala Lumpur, 50603, Malaysia.
| | - Toh-Seok Kam
- Department of Chemistry, Faculty of Science, Universiti Malaya, Kuala Lumpur, 50603, Malaysia.
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2
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Zhu WT, Chen C, Zhao Q, Han LL, Yang M, Hao XJ, Zhang Y. Isolation and structure elucidation of tabercetimines A-D, four new quaternary monoterpenoid indole alkaloids from Tabernaemontana divaricata. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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3
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Taberdivamines A and B, two new quaternary indole alkaloids from Tabernaemontana divaricata. Tetrahedron Lett 2020. [DOI: 10.1016/j.tetlet.2020.152400] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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4
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Ahn HI, Park JU, Xuan Z, Kim JH. Pd-Catalyzed asymmetric [5 + 2] cycloaddition of vinylethylene carbonates and cyclic imines: access to N-fused 1,3-oxazepines. Org Biomol Chem 2020; 18:9826-9830. [DOI: 10.1039/d0ob02159h] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A facile route to access enantioenriched N-fused 1,3-oxazepines via Pd-catalyzed asymmetric [5 + 2] cycloaddition of vinylethylene carbonates and cyclic imines has been developed.
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Affiliation(s)
- Hye-In Ahn
- Department of Chemistry (BK21)
- Research Institute of Natural Science
- Gyeongsang National University
- 52828, Jinju
- Korea
| | - Jong-Un Park
- Department of Chemistry (BK21)
- Research Institute of Natural Science
- Gyeongsang National University
- 52828, Jinju
- Korea
| | - Zi Xuan
- Department of Chemistry (BK21)
- Research Institute of Natural Science
- Gyeongsang National University
- 52828, Jinju
- Korea
| | - Ju Hyun Kim
- Department of Chemistry (BK21)
- Research Institute of Natural Science
- Gyeongsang National University
- 52828, Jinju
- Korea
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Yeap JSY, Lim KH, Yong KT, Lim SH, Kam TS, Low YY. Lycopodium Alkaloids: Lycoplatyrine A, an Unusual Lycodine-Piperidine Adduct from Lycopodium platyrhizoma and the Absolute Configurations of Lycoplanine D and Lycogladine H. JOURNAL OF NATURAL PRODUCTS 2019; 82:324-329. [PMID: 30698428 DOI: 10.1021/acs.jnatprod.8b00754] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Three new Lycopodium alkaloids comprising two lycodine-type alkaloids (1, 2) and one fawcettimine alkaloid (3), in addition to 16 known alkaloids, were isolated from Lycopodium platyrhizoma. The structures of these alkaloids were elucidated based on analysis of their NMR and MS data. Lycoplatyrine A (1) represents an unusual lycodine-piperidine adduct. The structures and absolute configurations of lycoplanine D (hydroxy-des- N-methyl-α-obscurine, 10) and lycogladine H (11) were confirmed by X-ray diffraction analysis.
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Affiliation(s)
- Joanne Soon-Yee Yeap
- Department of Chemistry, Faculty of Science , University of Malaya , 50603 Kuala Lumpur , Malaysia
| | - Kuan-Hon Lim
- School of Pharmacy , University of Nottingham Malaysia Campus , Jalan Broga , 43500 Semenyih , Selangor , Malaysia
| | - Kien-Thai Yong
- Institute of Biological Sciences, Faculty of Science , University of Malaya , 50603 Kuala Lumpur , Malaysia
| | - Siew-Huah Lim
- Department of Chemistry, Faculty of Science , University of Malaya , 50603 Kuala Lumpur , Malaysia
| | - Toh-Seok Kam
- Department of Chemistry, Faculty of Science , University of Malaya , 50603 Kuala Lumpur , Malaysia
| | - Yun-Yee Low
- Department of Chemistry, Faculty of Science , University of Malaya , 50603 Kuala Lumpur , Malaysia
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Lavaud C, Massiot G. The Iboga Alkaloids. PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS 2017; 105:89-136. [PMID: 28194562 DOI: 10.1007/978-3-319-49712-9_2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Iboga alkaloids are a particular class of indolomonoterpenes most often characterized by an isoquinuclidine nucleus. Their first occurrence was detected in the roots of Tabernanthe iboga, a sacred plant to the people of Gabon, which made it cult object. Ibogaine is the main representative of this class of alkaloids and its psychoactive properties are well documented. It has been proposed as a drug cessation treatment and has a wide range of activities in targeting opioids, cocaine, and alcohol. The purpose of this chapter is to provide a background on this molecule and related compounds and to update knowledge on the most recent advances made. Difficulties linked to the status of ibogaine as a drug in several countries have hampered its development, but 18-methoxycoronaridine is currently under evaluation for the same purposes and for the treatment of leishmaniasis. The chapter is divided into six parts: an introduction aiming at defining what is called an iboga alkaloid, and this is followed by current knowledge on their biosynthesis, which unfortunately remains a "black box" as far as the key construction step is concerned. Many of these alkaloids are still being discovered and the third and fourth parts of the chapter discuss the analytical tools in use for this purpose and give lists of new monomeric and dimeric alkaloids belonging to this class. When necessary, the structures are discussed especially with regard to absolute configuration determinations, which remain a point of weakness in their assignments. Part V gives an account of progress made in the synthesis, partial and total, which the authors believe is key to providing solid solutions to the industrial development of the most promising molecules. The last part of the chapter is devoted to the biological properties of iboga alkaloids, with particular emphasis on ibogaine and 18-methoxycoronaridine.
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Affiliation(s)
- Catherine Lavaud
- Faculty of Pharmacy, Université de Reims Champagne-Ardenne, Institut de Chimie Moléculaire de Reims, UMR CNRS 7312, Case postale 44, UFR des Sciences Exactes et Naturelles, BP 1039, 51687, Reims, Cedex 2, France.
| | - Georges Massiot
- Université de Reims Champagne-Ardenne, Institut de Chimie Moléculaire de Reims, UMR CNRS 7312, Case postale 44, UFR des Sciences Exactes et Naturelles, BP 1039, 51687, Reims, Cedex 2, France
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Huang L, Dai LX, You SL. Enantioselective Synthesis of Indole-Annulated Medium-Sized Rings. J Am Chem Soc 2016; 138:5793-6. [DOI: 10.1021/jacs.6b02678] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Lin Huang
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of
Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Li-Xin Dai
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of
Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Shu-Li You
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of
Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
- Collaborative
Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
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Abubakar IB, Loh HS. A review on ethnobotany, pharmacology and phytochemistry of Tabernaemontana corymbosa. ACTA ACUST UNITED AC 2016; 68:423-32. [PMID: 26887962 DOI: 10.1111/jphp.12523] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 01/14/2016] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Tabernaemontana is a genus from the plant family, Apocynaceae with vast medicinal application and widespread distribution in the tropics and subtropics of Africa, Americas and Asia. The objective of this study is to critically evaluate the ethnobotany, medicinal uses, pharmacology and phytochemistry of the species, Tabernaemontana corymbosa (Roxb. ex Wall.) and provide information on the potential future application of alkaloids isolated from different parts of the plant. KEY FINDINGS T. corymbosa (Roxb. ex Wall.) parts are used as poultice, boiled juice, decoctions and infusions for treatment against ulceration, fracture, post-natal recovery, syphilis, fever, tumours and orchitis in Malaysia, China, Thailand and Bangladesh. Studies recorded alkaloids as the predominant phytochemicals in addition to phenols, saponins and sterols with vast bioactivities such as antimicrobial, analgesic, anthelmintic, vasorelaxation, antiviral and cytotoxicity. SUMMARY An evaluation of scientific data and traditional medicine revealed the medicinal uses of different parts of T. corymbosa (Roxb. ex Wall.) across Asia. Future studies exploring the structure-bioactivity relationship of alkaloids such as jerantinine and vincamajicine among others could potentially improve the future application towards reversing anticancer drug resistance.
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Affiliation(s)
- Ibrahim Babangida Abubakar
- School of Biosciences, Faculty of Science, The University of Nottingham Malaysia Campus, Semenyih, Selangor, Malaysia
| | - Hwei-San Loh
- School of Biosciences, Faculty of Science, The University of Nottingham Malaysia Campus, Semenyih, Selangor, Malaysia.,Biotechnology Research Centre, The University of Nottingham Malaysia Campus, Semenyih, Selangor, Malaysia
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Lim JL, Sim KS, Yong KT, Loong BJ, Ting KN, Lim SH, Low YY, Kam TS. Biologically active vallesamine, strychnan, and rhazinilam alkaloids from Alstonia: Pneumatophorine, a nor-secovallesamine with unusual incorporation of a 3-ethylpyridine moiety. PHYTOCHEMISTRY 2015; 117:317-324. [PMID: 26125941 DOI: 10.1016/j.phytochem.2015.06.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 04/22/2015] [Accepted: 06/22/2015] [Indexed: 06/04/2023]
Abstract
Four alkaloids comprising two vallesamine, one strychnan, and one pyranopyridine alkaloid, in addition to 32 other known alkaloids were isolated from two Malayan Alstonia species, Alstonia pneumatophora and Alstonia rostrata. The structures of these alkaloids were determined using NMR and MS analyses, and in one instance, confirmed by X-ray diffraction analysis. The nor-6,7-secovallesamine alkaloid, pneumatophorine, is notable for an unusual incorporation of a 3-ethylpyridine moiety in a monoterpenoid indole. The rhazinilam-type alkaloids (rhazinicine, nor-rhazinicine, rhazinal, and rhazinilam) showed strong cytotoxicity toward human KB, HCT-116, MDA-MB-231, and MRC-5 cells, while pneumatophorine, the uleine alkaloid undulifoline, and the strychnan alkaloids, N4-demethylalstogustine and echitamidine, induced concentration dependent relaxation in phenylephrine-precontracted rat aortic rings.
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Affiliation(s)
- Jun-Lee Lim
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kae-Shin Sim
- Institute of Biological Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kien-Thai Yong
- Institute of Biological Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Bi-Juin Loong
- Department of Biomedical Sciences, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia
| | - Kang-Nee Ting
- Department of Biomedical Sciences, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia
| | - Siew-Huah Lim
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Yun-Yee Low
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Toh-Seok Kam
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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Lim KH, Raja VJ, Bradshaw TD, Lim SH, Low YY, Kam TS. Ibogan, tacaman, and cytotoxic bisindole alkaloids from tabernaemontana. Cononusine, an iboga alkaloid with unusual incorporation of a pyrrolidone moiety. JOURNAL OF NATURAL PRODUCTS 2015; 78:1129-1138. [PMID: 25919190 DOI: 10.1021/acs.jnatprod.5b00117] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Six new indole alkaloids, viz., cononusine (1, a rare example of an iboga-pyrrolidone conjugate), ervaluteine (2), vincamajicine (3), tacamonidine (4), 6-oxoibogaine (5), and N(4)-chloromethylnorfluorocurarine chloride (6), and two new vobasinyl-iboga bisindole alkaloids, ervatensines A (7) and B (8), in addition to other known alkaloids, were isolated from the stem-bark extract of the Malayan Tabernaemontana corymbosa. The structures of these alkaloids were established on the basis of NMR and MS analyses and, in one instance (7), confirmed by X-ray diffraction analysis. Vincamajicine (3) showed appreciable activity in reversing multidrug resistance in vincristine-resistant KB cells (IC50 2.62 μM), while ervatensines A (7) and B (8) and two other known bisindoles displayed pronounced in vitro growth inhibitory activity against human KB cells (IC50 < 2 μM). Compounds 7 and 8 also showed good growth inhibitory activity against A549, MCF-7, MDA-468, HCT-116, and HT-29 cells (IC50 0.70-4.19 μM). Cell cycle and annexin V-FITC apoptosis assays indicated that compounds 7 and 8 inhibited proliferation of HCT-116 and MDA-468 cells, evoking apoptotic and necrotic cell death.
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Affiliation(s)
- Kuan-Hon Lim
- †School of Pharmacy, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia
| | - Vijay J Raja
- ‡School of Pharmacy, Centre for Biomolecular Sciences, The University of Nottingham, University Park, Nottingham, Nottinghamshire NG72RD, U.K
| | - Tracey D Bradshaw
- ‡School of Pharmacy, Centre for Biomolecular Sciences, The University of Nottingham, University Park, Nottingham, Nottinghamshire NG72RD, U.K
| | - Siew-Huah Lim
- §Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Yun-Yee Low
- §Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Toh-Seok Kam
- §Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Nge CE, Gan CY, Lim KH, Ting KN, Low YY, Kam TS. Criofolinine and Vernavosine, New Pentacyclic Indole Alkaloids Incorporating Pyrroloazepine and Pyridopyrimidine Moieties Derived from a Common Yohimbine Precursor. Org Lett 2014; 16:6330-3. [DOI: 10.1021/ol503072g] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Choy-Eng Nge
- Department
of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Chew-Yan Gan
- University Malaysia of Computer Science and Engineering, Jalan Alamanda 2, Precint 1, 62000 Putrajaya, Malaysia
| | | | | | - Yun-Yee Low
- Department
of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Toh-Seok Kam
- Department
of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Chiral separation of two diastereomeric pairs of enantiomers of novel alkaloid-lignan hybrids from Lobelia chinensis and determination of the tentative absolute configuration. J Chromatogr A 2013; 1311:134-9. [DOI: 10.1016/j.chroma.2013.08.085] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 08/21/2013] [Accepted: 08/23/2013] [Indexed: 11/21/2022]
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13
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Nge CE, Gan CY, Low YY, Thomas NF, Kam TS. Voatinggine and tabertinggine, pentacyclic indole alkaloids derived from an iboga precursor via a common cleavamine-type intermediate. Org Lett 2013; 15:4774-7. [PMID: 23991636 DOI: 10.1021/ol4021404] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two new indole alkaloids, voatinggine (1) and tabertinggine (2), which are characterized by previously unencountered natural product skeletons, were isolated from a Malayan Tabernaemontana species. The structures and absolute configuration of these alkaloids were determined using NMR and MS analysis, and X-ray diffraction analysis. A possible biogenetic pathway to these novel alkaloids from an iboga precursor, and via a common cleavamine-type intermediate, is presented.
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Affiliation(s)
- Choy-Eng Nge
- Department of Chemistry, Faculty of Science, University of Malaya , 50603 Kuala Lumpur, Malaysia
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Peng Z, Takenaka N. Applications of Helical-Chiral Pyridines as Organocatalysts in Asymmetric Synthesis. CHEM REC 2012; 13:28-42. [DOI: 10.1002/tcr.201200010] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Indexed: 11/09/2022]
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Jana GK, Paul S, Sinha S. Progress in the Synthesis of Iboga-alkaloids and their Congeners. ORG PREP PROCED INT 2011. [DOI: 10.1080/00304948.2011.629563] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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Gan CY, Etoh T, Hayashi M, Komiyama K, Kam TS. Leucoridines A-D, cytotoxic Strychnos-Strychnos bisindole alkaloids from Leuconotis. JOURNAL OF NATURAL PRODUCTS 2010; 73:1107-1111. [PMID: 20515042 DOI: 10.1021/np1001187] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Four new bisindole alkaloids of the Strychnos-Strychnos type, leucoridines A-D (1-4), were isolated from the stem-bark extract of Leuconotis griffithii. Alkaloids 1-4 showed moderate cytotoxicity against drug-sensitive and vincristine-resistant human KB cells.
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Affiliation(s)
- Chew-Yan Gan
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Takenaka N, Chen J, Captain B, Sarangthem RS, Chandrakumar A. Helical Chiral 2-Aminopyridinium Ions: A New Class of Hydrogen Bond Donor Catalysts. J Am Chem Soc 2010; 132:4536-7. [DOI: 10.1021/ja100539c] [Citation(s) in RCA: 161] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Norito Takenaka
- Department of Chemistry, University of Miami, 1301 Memorial Drive, Coral Gables, Florida 33146-0431
| | - Jinshui Chen
- Department of Chemistry, University of Miami, 1301 Memorial Drive, Coral Gables, Florida 33146-0431
| | - Burjor Captain
- Department of Chemistry, University of Miami, 1301 Memorial Drive, Coral Gables, Florida 33146-0431
| | | | - Appayee Chandrakumar
- Department of Chemistry, University of Miami, 1301 Memorial Drive, Coral Gables, Florida 33146-0431
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Jana GK, Sinha S. Synthesis of iboga alkaloids by Pd-catalyzed heteroannulation of 2-iodoaniline with an internal alkyne as the key step. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.01.037] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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19
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Low YY, Lim KH, Choo YM, Pang HS, Etoh T, Hayashi M, Komiyama K, Kam TS. Structure, biological activity, and a biomimetic partial synthesis of the lirofolines, novel pentacylic indole alkaloids from Tabernaemontana. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2009.10.122] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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20
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Ishikura M, Yamada K, Abe T. Simple indole alkaloids and those with a nonrearranged monoterpenoid unit. Nat Prod Rep 2010; 27:1630-80. [DOI: 10.1039/c005345g] [Citation(s) in RCA: 210] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Gan CY, Low YY, Etoh T, Hayashi M, Komiyama K, Kam TS. Leuconicines A-G and (-)-eburnamaline, biologically active strychnan and eburnan alkaloids from Leuconotis. JOURNAL OF NATURAL PRODUCTS 2009; 72:2098-2103. [PMID: 20035556 DOI: 10.1021/np900576b] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Seven new indole alkaloids of the Strychnos type, leuconicines A-G (1-7), and a new eburnan alkaloid, (-)-eburnamaline (8), were isolated from the stem-bark extract of two Malayan Leuconotis species. The structures of these alkaloids were established using NMR and MS analysis and in the case of 8 also by partial synthesis. Alkaloids 1-5 reversed multidrug resistance in vincristine-resistant KB cells.
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Affiliation(s)
- Chew-Yan Gan
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, Iwaki Meisei University, 5-5-1 Iino, Chuo-dai, Iwaki, Fukushima 970-8551, Japan
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Gan CY, Robinson WT, Etoh T, Hayashi M, Komiyama K, Kam TS. Leucophyllidine, a cytotoxic bisindole alkaloid constituted from the union of an eburnan and a new vinylquinoline alkaloid. Org Lett 2009; 11:3962-5. [PMID: 19708704 DOI: 10.1021/ol9016172] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A cytotoxic bisindole alkaloid possessing an unprecedented structure constituted from the union of an eburnan half and a novel vinylquinoline alkaloid has been isolated from Leuconotis griffithii. The structure was established by analysis of the spectroscopic data and confirmed by X-ray diffraction analysis. A possible biogenetic pathway to the novel quinolinic coupling partner is presented from an Aspidosperma precursor.
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Affiliation(s)
- Chew-Yan Gan
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Lim KH, Kam TS. Conomicidines A and B, Unusual Alkaloid-Hydroxycinnamyl Alcohol Conjugates fromTabernaemontana corymbosa. Helv Chim Acta 2009. [DOI: 10.1002/hlca.200900093] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Lim KH, Sim KM, Tan GH, Kam TS. Four tetracyclic oxindole alkaloids and a taberpsychine derivative from a Malayan Tabernaemontana. PHYTOCHEMISTRY 2009; 70:1182-1186. [PMID: 19643450 DOI: 10.1016/j.phytochem.2009.06.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2009] [Revised: 05/29/2009] [Accepted: 06/11/2009] [Indexed: 05/26/2023]
Abstract
Four tetracyclic oxindole alkaloids, 7(R)- and 7(S)-geissoschizol oxindole (1 and 2), 7(R),16(R)- and 7(S),16(R)-19(E)-isositsirikine oxindole (3 and 4), in addition to a taberpsychine derivative, N(4)-demethyltaberpsychine (5), were isolated from the Malayan Tabernaemontana corymbosa and the structures were established using NMR and MS analysis.
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Affiliation(s)
- Kuan-Hon Lim
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kooi-Mow Sim
- Department of Chemical Science, Faculty of Science, Engineering and Technology, Universiti Tunku Abdul Rahman, Jalan Universiti, Bandar Barat, 31900 Kampar, Perak, Malaysia
| | - Guan-Huat Tan
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Toh-Seok Kam
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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