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Greger H. Comparative phytochemistry of flavaglines (= rocaglamides), a group of highly bioactive flavolignans from Aglaia species (Meliaceae). PHYTOCHEMISTRY REVIEWS : PROCEEDINGS OF THE PHYTOCHEMICAL SOCIETY OF EUROPE 2022; 21:725-764. [PMID: 34104125 PMCID: PMC8176878 DOI: 10.1007/s11101-021-09761-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 05/17/2021] [Indexed: 05/07/2023]
Abstract
Flavaglines are formed by cycloaddition of a flavonoid nucleus with a cinnamic acid moiety representing a typical chemical character of the genus Aglaia of the family Meliaceae. Based on biosynthetic considerations 148 derivatives are grouped together into three skeletal types representing 77 cyclopenta[b]benzofurans, 61 cyclopenta[bc]benzopyrans, and 10 benzo[b]oxepines. Apart from different hydroxy, methoxy, and methylenedioxy groups of the aromatic rings, important structural variation is created by different substitutions and stereochemistries of the central cyclopentane ring. Putrescine-derived bisamides constitute important building blocks occurring as cyclic 2-aminopyrrolidines or in an open-chained form, and are involved in the formation of pyrimidinone flavaglines. Regarding the central role of cinnamic acid in the formation of the basic skeleton, rocagloic acid represents a biosynthetic precursor from which aglafoline- and rocaglamide-type cyclopentabenzofurans can be derived, while those of the rocaglaol-type are the result of decarboxylation. Broad-based comparison revealed characteristic substitution trends which contribute as chemical markers to natural delimitation and grouping of taxonomically problematic Aglaia species. A wide variety of biological activities ranges from insecticidal, antifungal, antiprotozoal, and anti-inflammatory properties, especially to pronounced anticancer and antiviral activities. The high insecticidal activity of flavaglines is comparable with that of the well-known natural insecticide azadirachtin. Comparative feeding experiments informed about structure-activity relationships and exhibited different substitutions of the cyclopentane ring essential for insecticidal activity. Parallel studies on the antiproliferative activity of flavaglines in various tumor cell lines revealed similar structural prerequisites that let expect corresponding molecular mechanisms. An important structural modification with very high cytotoxic potency was found in the benzofuran silvestrol characterized by an unusual dioxanyloxy subunit. It possessed comparable cytotoxicity to that of the natural anticancer compounds paclitaxel (Taxol®) and camptothecin without effecting normal cells. The primary effect was the inhibition of protein synthesis by binding to the translation initiation factor eIF4A, an ATP-dependent DEAD-box RNA helicase. Flavaglines were also shown to bind to prohibitins (PHB) responsible for regulation of important signaling pathways, and to inhibit the transcriptional factor HSF1 deeply involved in metabolic programming, survival, and proliferation of cancer cells. Flavaglines were shown to be not only promising anticancer agents but gained now also high expectations as agents against emerging RNA viruses like SARS-CoV-2. Targeting the helicase eIF4A with flavaglines was recently described as pan-viral strategy for minimizing the impact of future RNA virus pandemics.
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Affiliation(s)
- Harald Greger
- Chemodiversity Research Group, Faculty of Life Sciences, University of Vienna, Rennweg 14, 1030 Wien, Austria
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Agarwal G, Chang LS, Soejarto DD, Kinghorn AD. Update on Phytochemical and Biological Studies on Rocaglate Derivatives from Aglaia Species. PLANTA MEDICA 2021; 87:937-948. [PMID: 33784769 PMCID: PMC8481333 DOI: 10.1055/a-1401-9562] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
With about 120 species, Aglaia is one of the largest genera of the plant family Meliaceae (the mahogany plants). It is native to the tropical rainforests of the Indo-Australian region, ranging from India and Sri Lanka eastward to Polynesia and Micronesia. Various Aglaia species have been investigated since the 1960s for their phytochemical constituents and biological properties, with the cyclopenta[b]benzofurans (rocaglates or flavaglines) being of particular interest. Phytochemists, medicinal chemists, and biologists have conducted extensive research in establishing these secondary metabolites as potential lead compounds with antineoplastic and antiviral effects, among others. The varied biological properties of rocaglates can be attributed to their unusual structures and their ability to act as inhibitors of the eukaryotic translation initiation factor 4A (eIF4A), affecting protein translation. The present review provides an update on the recently reported phytochemical constituents of Aglaia species, focusing on rocaglate derivatives. Furthermore, laboratory work performed on investigating the biological activities of these chemical constituents is also covered.
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Affiliation(s)
- Garima Agarwal
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio, United States
| | - Long-Sheng Chang
- Center for Childhood Cancer and Blood Diseases, Abigail Wexner Research Institute, Nationwide Children’s Hospital, Columbus, Ohio, United States
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, Ohio, United States
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University College of Medicine, Columbus, Ohio, United States
- Department of Pathology, The Ohio State University College of Medicine, Columbus, Ohio, United States
| | - Djaja Doel Soejarto
- College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, United States
- Science and Education, Field Museum, Chicago, Illinois, United States
| | - A. Douglas Kinghorn
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio, United States
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Abalos NN, Ebajo VD, Camacho DH, Jacinto SD. Cytotoxic and Apoptotic Activity of Aglaforbesin Derivative Isolated from Aglaia loheri Merr. on HCT116 Human Colorectal Cancer Cells. Asian Pac J Cancer Prev 2021; 22:53-60. [PMID: 33507679 PMCID: PMC8184180 DOI: 10.31557/apjcp.2021.22.1.53] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Indexed: 12/28/2022] Open
Abstract
Background: The genus Aglaia (Meliaceae) is an established source of many anticancer compounds. The study evaluated the leaf extracts of Aglaia loheri, a tree native to the Philippines, as potential source of anticancer compounds. Methods: Using bioassay-guided fractionation, A. loheri leaf extract was subjected to various chromatographic techniques and step-wise application of MTT assay on human colorectal carcinoma cells, HCT116, to determine the cytotoxic fractions. The most cytotoxic HPLC isolate was structurally identified using 1D and 2D NMR and its apoptotic effect was assessed by JC-1 staining, caspase 3/7 assay and TUNEL assay. Results: After stepwise chromatography fractionation, an HPLC isolate, structurally identified as aglaforbesin derivative (AFD), demonstrated potent cytotoxicity against HCT116. AFD exhibited strong toxicity (IC50 = 1.13 ±0.07 µg/mL) and high selectivity on HCT116 than normal human kidney cells (HK-2). AFD-induced toxicity to HCT116 is possibly through the stimulation of the apoptotic signaling pathway via caspase 3/7 activation and DNA fragmentation independent of mitochondrial membrane depolarization. Conclusion: AFD exhibited selective cytotoxicity and apoptotic activity to HCT116 and could be further developed as anticancer drug lead.
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Affiliation(s)
- Norielyn N Abalos
- Institute of Biology, University of the Philippines Diliman, 1101, Quezon City, Philippines.,Department of Biology, University of San Carlos-Talamban Campus, 6000, Cebu City, Philippines
| | - Virgilio D Ebajo
- NMR Laboratory, Central Instrumentation Facility, De La Salle University, Laguna Campus, LTI Spine Road, Laguna Boulevard, Barangays Biñan and Malamig, Biñan City, Laguna, Philippines.,Chemistry Department, De La Salle University, 2401 Taft Avenue, 0922 Manila, Philippines
| | - Drexel H Camacho
- NMR Laboratory, Central Instrumentation Facility, De La Salle University, Laguna Campus, LTI Spine Road, Laguna Boulevard, Barangays Biñan and Malamig, Biñan City, Laguna, Philippines.,Chemistry Department, De La Salle University, 2401 Taft Avenue, 0922 Manila, Philippines
| | - Sonia D Jacinto
- Institute of Biology, University of the Philippines Diliman, 1101, Quezon City, Philippines
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Harneti D, Supratman U. Phytochemistry and biological activities of Aglaia species. PHYTOCHEMISTRY 2021; 181:112540. [PMID: 33130371 DOI: 10.1016/j.phytochem.2020.112540] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 05/13/2023]
Abstract
Aglaia is the largest genus in the Meliaceae family (also known as Mahagoni in Indonesia), consisting of over 150 species, of which 65 are indigenous to Indonesia. These species spread through the tropical regions, especially Southeast Asia as well as the Nothern part of Australia, and have been used in traditional medicine for the treatment of several diseases. However, preliminary chemical researches commenced in 1965, where dammarane-type triterpenoids, aglaiol was isolated, and the structure was determined by chemical reaction and spectroscopic methods. Several studies have been carried out on the stembark, bark, leaves, seeds and leaves in the last fifty five years, and about 291 metabolites have been isolated from the sesquiterpenoid, diterpenoid, triterpenoid, limonoid, steroid, lignan, and alkaloid groups, as well as flavagline, which known to be the largest. This specifically amounts to 34% of Aglaia species, reported to show cytotoxic and insecticidal potentials, and also the tendency for use as chemical markers for this species. The extracts and compounds obtained from Aglaia species are evaluated for potential biological activities, including cytotoxicity, insecticidal, anti-inflammatory, antifungal, molluscicidal, antituberculosis and antiviral effects. In addition, flavagline (rocaglamide) derivatives have been confirmed to exhibit exceptional cytotoxicity, and are, thus, considered lead compounds for further development. Therefore, the results support the concept of utilizing Aglaia species as a potential source for the production of biologically active compounds.
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Affiliation(s)
- Desi Harneti
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Jatinangor, 45363, Sumedang, West Java, Indonesia
| | - Unang Supratman
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Jatinangor, 45363, Sumedang, West Java, Indonesia; Central Laboratory, Universitas Padjadjaran, Jatinangor, 45363, Sumedang, West Java, Indonesia.
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Li A, Yang L, Geng X, Peng X, Lu T, Deng Y, Dong Y. Rocaglamide-A Potentiates Osteoblast Differentiation by Inhibiting NF-κB Signaling. Mol Cells 2015; 38:941-9. [PMID: 26549505 PMCID: PMC4673408 DOI: 10.14348/molcells.2015.2353] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 08/27/2015] [Accepted: 09/01/2015] [Indexed: 12/27/2022] Open
Abstract
Rheumatoid arthritis is a chronic inflammatory disease that leads to bone and cartilage erosion. The inhibition of osteoblast differentiation by the inflammatory factor TNF-α is critical for the pathogenesis of rheumatoid arthritis. To modulate TNF-α mediated inhibition of osteoblast differentiation is required to improve therapeutic efficacy of rheumatoid arthritis. Here, we explored the potential role of rocaglamide-A, a component of Aglaia plant, in osteoblast differentiation. Rocaglamide-A prevented TNF-α mediated inhibition of osteoblast differentiation, and promoted osteoblast differentiation directly, in both C2C12 and primary mesenchymal stromal cells. Mechanistically, Rocaglamide-A inhibited the phosphorylation of NF-κB component p65 protein and the accumulation of p65 in nucleus, which resulted in the diminished NF-κB responsible transcriptional activity. Oppositely, overexpression of p65 reversed rocaglamide-A's protective effects on osteoblast differentiation. Collectively, rocaglamide-A protected and stimulated osteoblast differentiation via blocking NF-κB pathway. It suggests that rocaglamide-A may be a good candidate to develop as therapeutic drug for rheumatoid arthritis associated bone loss diseases.
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Affiliation(s)
- Aiguo Li
- Department of Orthopedic Surgery, The First Affiliated Hospital of Xinxiang Medical University, Henan,
China
| | - Libin Yang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Xinxiang Medical University, Henan,
China
| | - Xiaolin Geng
- Department of Orthopedic Surgery, The First Affiliated Hospital of Xinxiang Medical University, Henan,
China
| | - Xingmei Peng
- Department of Oncology, The Third Affiliated Hospital of Xinxiang Medical University, Henan,
China
| | - Tan Lu
- Department of Orthopedic Surgery, The First Affiliated Hospital of Xinxiang Medical University, Henan,
China
| | - Yanjun Deng
- Department of Orthopedic Surgery, The First Affiliated Hospital of Xinxiang Medical University, Henan,
China
| | - Yuzheng Dong
- Department of Orthopedic Surgery, The First Affiliated Hospital of Xinxiang Medical University, Henan,
China
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The Natural Anticancer Compounds Rocaglamides Inhibit the Raf-MEK-ERK Pathway by Targeting Prohibitin 1 and 2. ACTA ACUST UNITED AC 2012; 19:1093-104. [DOI: 10.1016/j.chembiol.2012.07.012] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 06/12/2012] [Accepted: 07/10/2012] [Indexed: 12/19/2022]
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Astelbauer F, Gruber M, Brem B, Greger H, Obwaller A, Wernsdorfer G, Congpuong K, Wernsdorfer WH, Walochnik J. Activity of selected phytochemicals against Plasmodium falciparum. Acta Trop 2012; 123:96-100. [PMID: 22537982 DOI: 10.1016/j.actatropica.2012.04.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 03/31/2012] [Accepted: 04/03/2012] [Indexed: 01/03/2023]
Abstract
According to the WHO, in 2008, there were 247 million reported cases of malaria and nearly one million deaths from the disease. Parasite resistance against first-line drugs, including artemisinin and mefloquine, is increasing. In this study the plant-derived compounds aglafolin, rocaglamid, kokusaginine, arborine, arborinine and tuberostemonine were investigated for their anti-plasmodial activity in vitro. Fresh Plasmodium falciparum isolates were taken from patients in the area of Mae Sot, north-western Thailand in 2008 and the inhibition of schizont maturation was determined for the respective compounds. With inhibitory concentrations effecting 50%, 90% and 99% inhibition (IC(50), IC(90) and IC(99)) of 60.95 nM, 854.41 nM and 7351.49 nM, respectively, rocaglamid was the most active of the substances, closely followed by aglafoline with 53.49 nM, 864.55 nM and 8354.20 nM. The activity was significantly below that of artemisinin, but moderately higher than that of quinine. Arborine, arborinine, tuberostemonine and kokusaginine showed only marginal activity against P. falciparum characterized by IC(50) and IC(99) values higher than 350 nM and 180 μM, respectively, and regressions with relatively shallow slopes S>14.38. Analogues of rocaglamid and aglafoline merit further exploration of their anti-plasmodial activity.
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Affiliation(s)
- Florian Astelbauer
- Institute of Specific Prophylaxis and Tropical Medicine, Medical University of Vienna, Austria
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Malona JA, Cariou K, Spencer WT, Frontier AJ. Total synthesis of (±)-rocaglamide via oxidation-initiated Nazarov cyclization. J Org Chem 2012; 77:1891-908. [PMID: 22283818 DOI: 10.1021/jo202366c] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
This article describes the evolution of a Nazarov cyclization-based synthetic strategy targeting the anticancer, antiinflammatory, and insecticidal natural product (±)-rocaglamide. Initial pursuit of a polarized heteroaromatic Nazarov cyclization to construct the congested cyclopentane core revealed an unanticipated electronic bias in the pentadienyl cation. This reactivity was harnessed in a successful second-generation approach using an oxidation-initiated Nazarov cyclization of a heteroaryl alkoxyallene. Full details of these two approaches are given, as well as the characterization of undesired reaction pathways available to the Nazarov cyclization product. A sequence of experiments that led to an understanding of the unexpected reactivity of this key intermediate is described, which culminated in the successful total synthesis of (+)-rocaglamide.
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Affiliation(s)
- John A Malona
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
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Cai XH, Xie B, Guo H. Progress in the total synthesis of rocaglamide. ISRN ORGANIC CHEMISTRY 2011; 2011:239817. [PMID: 24052818 PMCID: PMC3767207 DOI: 10.5402/2011/239817] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2011] [Accepted: 02/13/2011] [Indexed: 11/23/2022]
Abstract
The first cyclopenta[b]benzofuran derivative, rocaglamide, from Aglaia elliptifolia, was found to exhibit considerable insecticidal activities and excellent potential as a therapeutic agent candidate in cancer chemotherapy; the genus Aglaia has been subjected to further investigation. Both the structural complexity of rocaglamide and its significant activity make it an attractive synthetic target. Stereoselective synthesis of the dense substitution pattern of these targets is a formidable synthetic challenge: the molecules bear five contiguous stereocenters and cis aryl groups on adjacent carbons. In past years of effort, only a handful of completed total syntheses have been reported, evidence of the difficulties associated with the synthesis of rocaglate natural products. The advance on total synthesis of rocaglamide was mainly reviewed from intramolecular cyclization and biomimetic cycloaddition approach.
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Affiliation(s)
- Xiao-hua Cai
- College of Chemistry and Environmental Science, Guizhou University for Nationalites, Guiyang 550025, China
| | - Bing Xie
- College of Chemistry and Environmental Science, Guizhou University for Nationalites, Guiyang 550025, China
| | - Hui Guo
- College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, China
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Ebada SS, Lajkiewicz N, Porco JA, Li-Weber M, Proksch P. Chemistry and biology of rocaglamides (= flavaglines) and related derivatives from aglaia species (meliaceae). PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS 2011; 94:1-58. [PMID: 21833837 PMCID: PMC4157394 DOI: 10.1007/978-3-7091-0748-5_1] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Sherif S. Ebada
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich-Heine University of Duesseldorf, Universitaetsstrasse 1, D-40225, Duesseldorf, Germany. Department of Pharmacognosy and Phytochemistry, Faculty of Pharmacy, Ain-Shams University, Organization of African Unity 1, 11566 Cairo, Egypt
| | - Neil Lajkiewicz
- Department of Chemistry and Center for Chemical Methodology and Library Development (CMLD-BU), Boston University, Commonwealth Avenue 590, Boston, MA 02215, USA
| | - John A. Porco
- Department of Chemistry and Center for Chemical Methodology and Library Development (CMLD-BU), Boston University, Commonwealth Avenue 590, Boston, MA 02215, USA
| | - Min Li-Weber
- Tumor Immunology Program (D030), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120, Heidelberg, Germany
| | - Peter Proksch
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich-Heine University of Duesseldorf, Universitaetsstrasse 1, D-40225, Duesseldorf, Germany
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Li H, Fu B, Wang MA, Li N, Liu WJ, Xie ZQ, Ma YQ, Qin Z. Total Synthesis and Biological Activity of (±)-Rocaglamide and Its 2,3-Di-epi Analogue. European J Org Chem 2008. [DOI: 10.1002/ejoc.200700905] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Greger H, Hofer M, Teichmann K, Schinnerl J, Pannell CM, Vajrodaya S, Hofer O. Amide-esters from Aglaia tenuicaulis--first representatives of a class of compounds structurally related to bisamides and flavaglines. PHYTOCHEMISTRY 2008; 69:928-38. [PMID: 18155259 DOI: 10.1016/j.phytochem.2007.10.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 10/10/2007] [Accepted: 10/12/2007] [Indexed: 05/13/2023]
Abstract
Six amide-esters and two sulphur-containing bisamides were isolated from the leaves, stem and root bark of Aglaia tenuicaulis together with two bisamides from the leaves of A. spectabilis. Their structures were elucidated by spectroscopic methods. The co-occurrence of amide-esters and bisamides suggests close biosynthetic connections replacing only one nitrogen atom of putrescine with oxygen. Putrescine appears to be the common building block linked to various acids from which the cinnamoyl moiety represents the prerequisite for an incorporation of bisamides into flavaglines. Corresponding amide-esters are apparently not incorporated, but closely related amide-alcohol derivatives were found as part of benzopyran and benzofuran flavaglines. The structure of a amide-alcohol is described, representing an artifact due to hydrolysis of an amide-ester during TLC purification. A hypothetical amide-amine building block is suggested to form the characteristic pyrimidinone structures only found in benzofuran flavaglines. Structural and biosynthetic connections between amide-esters, bisamides and flavaglines are discussed and the chemotaxonomic significance of accumulating specific derivatives within the genus Aglaia is highlighted.
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Affiliation(s)
- Harald Greger
- Comparative and Ecological Phytochemistry, Faculty Center of Botany, University of Vienna, Rennweg 14, A-1030 Wien, Austria.
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Bringmann G, Gulder TA, Reichert M, Gulder T. The online assignment of the absolute configuration of natural products: HPLC-CD in combination with quantum chemical CD calculations. Chirality 2008; 20:628-42. [DOI: 10.1002/chir.20557] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Kozlowski M, Dugan E, DiVirgilio E, Maksimenka K, Bringmann G. Asymmetric Total Synthesis of Nigerone andent-Nigerone: Enantioselective Oxidative Biaryl Coupling of Highly Hindered Naphthols. Adv Synth Catal 2007. [DOI: 10.1002/adsc.200600570] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Zhu JY, Lavrik IN, Mahlknecht U, Giaisi M, Proksch P, Krammer PH, Li-Weber M. The traditional Chinese herbal compound rocaglamide preferentially induces apoptosis in leukemia cells by modulation of mitogen-activated protein kinase activities. Int J Cancer 2007; 121:1839-46. [PMID: 17565740 DOI: 10.1002/ijc.22883] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
With an increasing cancer rate worldwide, there is an urgent quest for the improvement of anticancer drugs. One of the main problems of present chemotherapy in treatment of tumor patients is the toxicity of drugs. Most of the existent anticancer drugs, unfortunately, attack also proliferating normal cells. In recent years, traditional Chinese herbal remedies have gradually gained considerable attention as a new source of anticancer drugs. Although their healing mechanisms are still largely unknown, some of the drugs have been used to help cancer patients fight their disease at reduced side effects compared to other treatments. In our study, we show that Rocaglamide (Roc), derived from the traditional Chinese medicinal plants Aglaia, induces apoptosis through the intrinsic death pathway in various human leukemia cell lines and in acute lymphoblastic leukemia, chronic myeloid leukemia and acute myeloid leukemia cells freshly isolated from patients. Investigation of the molecular mechanisms by which Roc kills tumors revealed that it induces a consistent activation of the stress-response mitogen-activated protein kinase (MAPK) p38 accompanied with a long-term suppression of the survival MAPK extracellular signal-regulated kinase. These events affect proapoptotic Bcl-2 family proteins leading to depolarization of the mitochondrial membrane potential and trigger caspase-mediated apoptosis involving caspase-9, -8, -3 and -2. Importantly, Roc shows no effects on MAPKs in normal lymphocytes and therefore has no or very low toxicity on healthy cells. Up to now, more than 50 different Roc derivatives have been isolated from Aglaia. Our study suggests that Roc derivatives may be promising candidates for the development of new drugs against hematologic malignancies.
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MESH Headings
- Acute Disease
- Antineoplastic Agents/pharmacology
- Apoptosis/drug effects
- Benzofurans/pharmacology
- Cell Line, Tumor
- Drugs, Chinese Herbal/pharmacology
- Humans
- JNK Mitogen-Activated Protein Kinases/metabolism
- Leukemia/drug therapy
- Leukemia/enzymology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/enzymology
- Leukemia, Myeloid/drug therapy
- Leukemia, Myeloid/enzymology
- Mitogen-Activated Protein Kinases/drug effects
- Mitogen-Activated Protein Kinases/metabolism
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/enzymology
- Tubulin/metabolism
- p38 Mitogen-Activated Protein Kinases/metabolism
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Affiliation(s)
- Jia Y Zhu
- Tumor Immunology Program (D030), German Cancer Research Center (DKFZ), Heidelberg, Germany
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Kim S, Chin YW, Su BN, Riswan S, Kardono LBS, Afriastini JJ, Chai H, Farnsworth NR, Cordell GA, Swanson SM, Kinghorn AD. Cytotoxic flavaglines and bisamides from Aglaia edulis. JOURNAL OF NATURAL PRODUCTS 2006; 69:1769-75. [PMID: 17190457 PMCID: PMC2471874 DOI: 10.1021/np060428x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Two new cyclopenta[b]benzofurans, aglaroxin A 1-O-acetate (2) and 3'-methoxyaglaroxin A 1-O-acetate (3), a new benzo[b]oxepine, 19,20-dehydroedulisone A (4), and five new cyclopenta[bc]benzopyrans, edulirin A (5), edulirin A 10-O-acetate (6), 19,20-dehydroedulirin A (7), isoedulirin A (8), and edulirin B (9), were isolated from the bark of Aglaia edulis, along with one known cyclopenta[b]benzofuran, aglaroxin A (1). Additionally, four new amides, aglamides A-D (10-13), as well as three known compounds, aglalactone, scopoletin, and 5-hydroxy-3,6,7,4'-tetramethoxyflavone, were isolated from the leaves and/or twigs of this species. The structures of the new compounds (2-13) were elucidated by interpretation of their spectroscopic data. All isolates obtained in this study were evaluated for cytotoxicity against both several human cancer cell lines (Lu1, LNCaP, and MCF-7) and a nontumorigenic (HUVEC) cell line. Among these isolates, the cyclopenta[b]benzofurans (1-3) exhibited potent in vitro cytotoxic activity (ED50 range 0.001 to 0.8 microg/mL). Aglaroxin A 1-O-acetate (2) was further evaluated in the in vivo P388 lymphocytic leukemia model, by intraperitoneal injection, but found to be inactive in this model.
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Chumkaew P, Kato S, Chantrapromma K. Potent cytotoxic rocaglamide derivatives from the fruits of Amoora cucullata. Chem Pharm Bull (Tokyo) 2006; 54:1344-6. [PMID: 16946551 DOI: 10.1248/cpb.54.1344] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two new rocaglamide derivatives, 1-O-formylrocagloic acid (1) and 3'-hydroxy rocagloic acid (2), together with five known compounds, rocaglaol (3), rocagloic acid (4), 3'-hydroxymethylrocaglate (5), 1-O-formylmethyl rocaglate (6), and methylrocaglate (7), were isolated from the fruits of Amoora cucullata. Their structures were elucidated by spectroscopic methods. Compounds 1-3, 6, and 7 exhibited potent cytotoxicity against KB, BC, and NCI-H187 cell lines, whereas 4 and 5 showed selective cytotoxicity against NCI-H187 cell line.
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Affiliation(s)
- Parinuch Chumkaew
- School of Science and Research Unit of Natural Products Utilization, Walailak University, Thasala, Nakhon Si Thammarat 80160, Thailand
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20
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Hwang BY, Su BN, Chai H, Mi Q, Kardono LBS, Afriastini JJ, Riswan S, Santarsiero BD, Mesecar AD, Wild R, Fairchild CR, Vite GD, Rose WC, Farnsworth NR, Cordell GA, Pezzuto JM, Swanson SM, Kinghorn AD. Silvestrol and episilvestrol, potential anticancer rocaglate derivatives from Aglaia silvestris. J Org Chem 2004; 69:3350-8. [PMID: 15132542 DOI: 10.1021/jo040120f] [Citation(s) in RCA: 144] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two cytotoxic rocaglate derivatives possessing an unusual dioxanyloxy unit, silvestrol (1) and episilvestrol (2), were isolated from the fruits and twigs of Aglaia silvestris by bioassay-guided fractionation monitored with a human oral epidermoid carcinoma (KB) cell line. Additionally, two new baccharane-type triterpenoids, 17,24-epoxy-25-hydroxybaccharan-3-one (3) and 17,24-epoxy-25-hydroxy-3-oxobaccharan-21-oic acid (4), as well as eleven known compounds, 1beta,6alpha-dihydroxy-4(15)-eudesmene (5), ferulic acid (6), grasshopper ketone (7), apigenin, cabraleone, chrysoeriol, 1beta,4beta-dihydroxy-6alpha,15alpha-epoxyeudesmane, 4-hydroxy-3-methoxyacetophenone, 4-hydroxyphenethyl alcohol, ocotillone, and beta-sitosterol 3-O-beta-D-glucopyranoside, were also isolated and characterized. The structures of compounds 1-4 were elucidated by spectroscopic studies and by chemical transformation. The absolute stereochemistry of silvestrol (1) was established by a X-ray diffraction study of its di-p-bromobenzoate derivative, and the structure of 3 was also confirmed by single-crystal X-ray diffraction. The isolates and chemical transformation products were evaluated for cytotoxicity against several human cancer cell lines, and silvestrol (1) and episilvestrol (2) exhibited potent in vitro cytotoxic activity. Silvestrol (1) was further evaluated in vivo in the hollow fiber test and in the murine P-388 leukemia model.
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Affiliation(s)
- Bang Yeon Hwang
- Program for Collaborative Research in the Pharmaceutical Sciences, University of Illinois at Chicago, Chicago, Illinois 60612, USA
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21
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Wang BG, Ebel R, Wang CY, Edrada RA, Wray V, Proksch P. Aglacins I-K, three highly methoxylated lignans from Aglaia cordata. JOURNAL OF NATURAL PRODUCTS 2004; 67:682-4. [PMID: 15104504 DOI: 10.1021/np034057l] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Further chemical investigation of the stem bark of Aglaia cordata has led to the isolation and identification of three new lignans, namely, aglacins I-K (1-3), all of which contain two contiguous trimethoxylated phenyl systems. Among them, aglacins I and J (1 and 2) are new members of the aryltetralin cyclic lactol class, while aglacin K (3) is a new example of tetrahydrofuran lignan. The structures of these compounds were established on the basis of spectroscopic data interpretation.
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Affiliation(s)
- Bin-Gui Wang
- Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Nanhai Road 7, Qingdao 266071, People's Republic of China.
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Rivero-Cruz JF, Chai HB, Kardono LBS, Setyowati FM, Afriatini JJ, Riswan S, Farnsworth NR, Cordell GA, Pezzuto JM, Swanson SM, Kinghorn AD. Cytotoxic constituents of the twigs and leaves of Aglaia rubiginosa. JOURNAL OF NATURAL PRODUCTS 2004; 67:343-7. [PMID: 15043407 DOI: 10.1021/np0304417] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Activity-guided fractionation of a CHCl(3)-soluble extract of the twigs of Aglaia rubiginosa, using human oral epidermoid carcinoma (KB) cells as a monitor, led to the isolation of a new naturally occurring cyclopenta[b]benzofuran, 1-O-acetylrocaglaol (1), along with seven known compounds, methyl rocaglate (2), rocagloic acid (3), 1-O-acetylmethyl rocaglate (4), desyclamide, eryodictiol, 5-hydroxy-3,7,4'-trimethoxyflavone, and naringenin. A CHCl(3) extract of the leaves of A. rubiginosa yielded the new compound (3S,4R,22R)-cholest-7,24-diene-3,4,22-triol (5), as well as 11 known compounds, including 2 and 4 and cabraleone, dammarelonic acid, (20S,23E)-20,25-dihydroxy-3,4-secodammara-4(28),23-dienoic acid, (20S,23E)-20,25-dihydroxy-3,4-secodammara-4(28),23-dienoic acid methyl ester, (3beta,4beta,22R)-ergosta-5,24(24')-diene-3,4,22-triol, ocotillone, shoreic acid, beta-sitosterol, and beta-sitosterol glycoside. The structures of 1 and 5 were elucidated by spectral and chemical methods. Isolates were evaluated with a human cancer cell panel, and compounds 1-4 were found to exhibit potent cytotoxic activity.
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Affiliation(s)
- J Fausto Rivero-Cruz
- Program for Collaborative Research in the Pharmaceutical Sciences and Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, USA
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23
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Bringmann G, Mühlbacher J, Messer K, Dreyer M, Ebel R, Nugroho BW, Wray V, Proksch P. Cyclorocaglamide, the first bridged cyclopentatetrahydrobenzofuran, and a related "open chain" rocaglamide derivative from Aglaia oligophylla. JOURNAL OF NATURAL PRODUCTS 2003; 66:80-5. [PMID: 12542350 DOI: 10.1021/np020291k] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Two rocaglamide-related natural products, the previously known compound 6-demethoxy-10-hydroxy-11-methoxy-6,7-methylendioxyrocaglamide (3), and cyclorocaglamide (4), its 8b,10-anhydro analogue, have been isolated from the tropical plant Aglaia oligophylla. Compound 4 is the first bridged cyclopentatetrahydrobenzofuran natural product, and it exhibited a CD spectrum virtually opposite that of all the other rocaglamide natural products known so far, but it still has the same absolute configuration at all stereogenic centers of the basic molecular framework. This was shown unequivocally by quantum chemical CD calculations (here based on molecular dynamics-weighted force field structures) and was finally confirmed experimentally, by a "biomimetic-type" cyclization of 3 to give 4, with the expected "inversion" of the CD spectrum. The opposite chiroptical properties of 3 and 4, despite their homochiral character, underline the necessity of handling chiroptical data with the greatest care, e.g., by simulating them by quantum chemical CD calculations. Compound 3 exhibited an LC(50) of 2.5 ppm when evaluated against neonate larvae of Spodoptera littoralis, while 4 was inactive in this assay up to 100 ppm.
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Affiliation(s)
- Gerhard Bringmann
- Institut für Organische Chemie der Universität, Am Hubland, D-97074 Würzburg, Germany.
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Bringmann G, Lang G. Full absolute stereostructures of natural products directly from crude extracts: The HPLC-MS/ MS-NMR-CD 'triad'. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2003; 37:89-116. [PMID: 15825641 DOI: 10.1007/978-3-642-55519-0_4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
This chapter deals with an efficient methodology available in our Center of Excellence, BIOTECmarin: the novel analytical 'triad' HPLC-MS/MS-NMR-CD. By this method, which was, in this complemented form, first introduced into phytochemical research by our group, we can not only rapidly identify known structures, but can also investigate new metabolites and establish their full absolute stereostructures online, directly from crude extracts, without the necessity of first isolating the compounds. The LC-CD option, which we have been using for the first time in natural products analysis, becomes even more valuable by the possibility of interpreting the online CD spectra by their simulation or prediction through quantum chemical calculation, thus avoiding the usual, often risky, empirical comparison with the CD spectra of (sometimes not so related) compounds of known absolute stereostructure or the application of (sometimes not really applicable) likewise empirical CD rules. The hyphenated analytical methods are additionally complemented by our synthetic expertise, again involving new concepts and strategies developed in our group. The methods and their application will first be explained and exemplified for plant-derived ('terrestrial') natural products, for which they were initially developed, and will then be applied to the online structural elucidation of novel natural products from marine organisms.
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Affiliation(s)
- G Bringmann
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
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25
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Bremner JB. Chapter 7 Seven-membered rings. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0959-6380(03)80019-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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26
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Wang BG, Ebel R, Wang CY, Wray V, Proksch P. New methoxylated aryltetrahydronaphthalene lignans and a norlignan from Aglaia cordata. Tetrahedron Lett 2002. [DOI: 10.1016/s0040-4039(02)01180-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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27
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Bringmann G, Günther C, Ochse M, Schupp O, Tasler S. Biaryls in nature: a multi-facetted class of stereochemically, biosynthetically, and pharmacologically intriguing secondary metabolites. FORTSCHRITTE DER CHEMIE ORGANISCHER NATURSTOFFE = PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS. PROGRES DANS LA CHIMIE DES SUBSTANCES ORGANIQUES NATURELLES 2002; 82:1-249. [PMID: 11892255 DOI: 10.1007/978-3-7091-6227-9_1] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Affiliation(s)
- G Bringmann
- Institut für Organische Chemie, Universität Würzburg, Germany.
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28
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Hong BC, Shr YJ, Liao JH. Unprecedented microwave effects on the cycloaddition of fulvenes. A new approach to the construction of polycyclic ring systems. Org Lett 2002; 4:663-6. [PMID: 11843617 DOI: 10.1021/ol017304q] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] Novel cycloaddition reactions between fulvenes and various alkenes and alkynes are promoted by the use of microwave irradiation. These processes result in the formation of intriguing polycyclic ring systems such as those found in isobarbatene, alcyopterosin, and enokipodin A. Importantly, these reactions do not occur under conventional thermolytic conditions.
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Affiliation(s)
- Bor-Cherng Hong
- Department of Chemistry, National Chung Cheng University, Chia-Yi, 621, Taiwan, ROC.
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29
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Yamashita M, Okuyama K, Kawajiri T, Takada A, Inagaki Y, Nakano H, Tomiyama M, Ohnaka A, Terayama I, Kawasaki I, Ohta S. A novel tandem reaction of 3-substituted coumarins with two equivalents of dimethylsulfoxonium ylide to 2-substituted cyclopenta[b]benzofuran-3-ol derivatives. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)00014-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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30
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Chapter 5.3 Five-membered ring systems: Furans and benzofurans. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s0959-6380(02)80009-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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31
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Wang BG, Ebel R, Nugroho BW, Prijono D, Frank W, Steube KG, Hao XJ, Proksch P. Aglacins A-D, first representatives of a new class of aryltetralin cyclic ether lignans from Aglaia cordata. JOURNAL OF NATURAL PRODUCTS 2001; 64:1521-1526. [PMID: 11754603 DOI: 10.1021/np0102962] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Four new metabolites, aglacins A-D (1-4), were identified from the methanol extract of the stem bark of Aglaia cordata. These compounds represent a new class of aryltetralin cyclic ether lignan. The structure of aglacin A (1) including the absolute configuration was elucidated by interpretation of spectral data, X-ray crystal structure determination, and employing the modified Mosher's method. In addition, three other derivatives, aglacins B-D (2-4), were isolated and identified by spectral means.
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Affiliation(s)
- B G Wang
- Institut für Pharmazeutische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, Geb. 26.23, D-40225 Düsseldorf, Germany
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32
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Feling R, Polborn K, Steglich W, Mühlbacher J, Bringmann G. The absolute configuration of the mushroom metabolites involutin and chamonixin. Tetrahedron 2001. [DOI: 10.1016/s0040-4020(01)00761-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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33
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Bringmann G, Mühlbacher J, Repges C, Fleischhauer J. MD-based CD calculations for the assignment of the absolute axial configuration of the naphthylisoquinoline alkaloid dioncophylline A. J Comput Chem 2001. [DOI: 10.1002/jcc.1084] [Citation(s) in RCA: 34] [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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34
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Schneider C, Bohnenstengel FI, Nugroho BW, Wray V, Witte L, Hung PD, Kiet LC, Proksch P. Insecticidal rocaglamide derivatives from Aglaia spectabilis (Meliaceae). PHYTOCHEMISTRY 2000; 54:731-736. [PMID: 11014256 DOI: 10.1016/s0031-9422(00)00205-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Bark of Aglaia spectabilis collected on the island of Phu Quoc (Vietnam) yielded insecticidal cyclopentatetrahydrobenzofurans of the rocaglamide type including four new natural products. Structure elucidation of the new compounds is described. All rocaglamide derivatives isolated exhibited strong insecticidal activity towards neonate larvae of the polyphagous pest insect Spodoptera littoralis when incorporated into an artificial diet. LC50 values varied from 0.8 to 80 ppm. The most active compounds isolated, methylrocaglate and C-3' hydroxylmethylrocaglate, were similar with regard to their insecticidal activity to the well-known natural insecticide azadirachtin.
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Affiliation(s)
- C Schneider
- Institut für Phamazeutische Biologie, Heinrich Heine Universität Düsseldorf Germany
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