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James Clarke, Karl J Bonney, Muhammad Yaqoob, Savade Solanki, Henry S Rzepa, Andrew J P White, David S Millan, D Christopher Braddock
The total syntheses of 12-epoxyobtusallene IV, 12-epoxyobtusallene II, obtusallene X, marilzabicycloallene C, and marilzabicycloallene D as halogenated C15-acetogenin 12-membered bicyclic and tricyclic ether bromoallene-containing marine metabolites from Laurencia species are described. Two enantiomerically pure C4-epimeric dioxabicyclo[8.2.1]tridecenes were synthesized by E-selective ring-closing metathesis where their absolute stereochemistry was previously set via catalytic asymmetric homoallylic epoxidation and elaborated via regioselective epoxide-ring opening and diastereoselective bromoetherification...
October 5, 2016: Journal of Organic Chemistry
Robert Rottscholl, Marlen Haegele, Britta Jainsch, Hong Xu, Gesine Respondek, Matthias Höllerhage, Thomas W Rösler, Emilie Bony, Jessica Le Ven, Vincent Guérineau, Isabelle Schmitz-Afonso, Pierre Champy, Wolfgang H Oertel, Elizabeth S Yamada, Günter U Höglinger
In the pathogenesis of tauopathies genetic and environmental factors have been identified. While familial clustering led to the identification of mutations in MAPT encoding the microtubule-associated protein tau, the high incidence of a sporadic tauopathy endemic in Guadeloupe was linked to the plant-derived mitochondrial complex I inhibitor annonacin. The interaction of both factors was studied in the present work in a realistic paradigm over a period of 12 months. Mice overexpressing either human wild-type tau or R406W mutant tau as well as non-transgenic mice received either regular drinking water or commercially available tropical fruit juice made of soursop (Annona muricata L...
August 29, 2016: Journal of Neurochemistry
Yong Chen, Yayun Chen, Yeye Shi, Chengyao Ma, Xunan Wang, Yue Li, Yunjie Miao, Jianwei Chen, Xiang Li
CONTEXT: Custard apple (Annona squamosa Linn.) is an edible tropical fruit, and its seeds have been used to treat "malignant sore" (cancer) and other usage as insecticide. A comparison of extraction processes, chemical composition analysis and antitumor activity of A. squamosa seed oil (ASO) were investigated. MATERIALS AND METHODS: The optimal extraction parameters of ASO were established by comparing percolation, soxhlet, ultrasonic and SFE-CO2 extraction methods...
August 23, 2016: Journal of Ethnopharmacology
Juliane Adrian, Christian B W Stark
An iterative strategy for the stereodivergent synthesis of unbranched 1,5,9,n-polyenes (and -polyynes) was investigated. Starting from a terminal alkyne the iteration cycle consists of a C3 extension (allylation), a chemoselective hydroboration, an alkyne reduction, and an oxidation of the associated alcohol with subsequent C1 homologation. Double bond geometry is controlled using stereoselective alkyne reductions, employing either the Lindlar hydrogenation protocol or an aluminum hydride reduction. In a model sequence it was demonstrated that the strategy is applicable to the synthesis of 1,5,9,n-polyenes with any possible double bond configuration accessible in equally high efficiency and selectivity...
September 16, 2016: Journal of Organic Chemistry
Iljin Shin, Dongjoo Lee, Hyoungsu Kim
The first asymmetric total synthesis and subsequent structure revision of (-)-bisezakyne A, a Laurencia C15 acetogenin from Alpysia oculifera, has been accomplished. Our substrate-controlled synthesis of this oxolane natural product features a highly stereoselective "protecting-group-dependent" intramolecular amide enolate alkylation strategy for the synthesis of the key 9,10-trans-9,12-cis-10-hydroxytetrahydrofuran intermediate through "nonchelate" control. In addition, our synthesis determined the absolute configuration of the halogenated marine natural product...
September 2, 2016: Organic Letters
Usein M Dzhemilev, Vladimir A D'yakonov, Regina A Tuktarova, Lilya U Dzhemileva, Svetlana R Ishmukhametova, Milyausha M Yunusbaeva, Armin de Meijere
An original synthesis of the acetogenin muricadienin, the bioprecursor of solamin, has been developed. The key step in the five-step 41% overall yield synthesis is the catalytic cross-cyclomagnesiation reaction of functionally substituted 1,2-dienes with EtMgBr in the presence of Cp2TiCl2 and magnesium metal. It has been demonstrated for the first time that muricadienin exhibits a moderate in vitro inhibitory activity against topoisomerases I and IIα, key cell cycle enzymes. Using flow cytometry, muricadienin was shown to have high cytotoxicity toward the HEK293 kidney cancer cells (IC50 0...
August 26, 2016: Journal of Natural Products
Marilza da Silva Costa, Sérgio Oliveira de Paula, Gustavo Ferreira Martins, José Cola Zanuncio, Antônio Euzébio Goulart Santana, José Eduardo Serrão
Annonaceous acetogenins are botanical compounds with good potential for use as insecticides. In the vector, Aedes aegypti (L.) (Diptera: Culicidae), squamocin (acetogenin) has been reported to be a larvicide and cytotoxic, but the modes of action of this molecule are still poorly understood. This study evaluated the changes in the cell morphology, and in the expression of genes, for autophagy (Atg1 and Atg8), for membrane ion transporter V-ATPase, and for water channel aquaporin-4 (Aqp4) in the midgut of A...
2016: PloS One
Jingyi Hong, Yanhong Li, Yijing Li, Yao Xiao, Haixue Kuang, Xiangtao Wang
Annonaceous acetogenins (ACGs) have shown superior antitumor activity against a variety of cancer cell lines, but their clinical application has been limited by their poor solubility. In this study, ACGs-nanosuspensions (NSps) were successfully prepared by a precipitation ultrasonic method using monomethoxypoly (ethylene glycol)2000-poly (ε-caprolactone)2000 (mPEG2000-PCL2000) as a stabilizer. The resultant ACGs-NSps had a mean particle size of 123.2 nm, a zeta potential of -20.17 mV, and a high drug payload of 73...
2016: International Journal of Nanomedicine
Fei Yuan, Ganggang Bai, Yunjie Miao, Yong Chen, Xiang Li, Jianwei Chen
CONTEXT: Multidrug resistance (MDR) is a major obstacle to efficient therapy of cancers. It is a prime concern for researchers to find compounds with anti-proliferative activity on MDR cell lines. In recent years, annonaceous acetogenins (ACGs) were reported to have anti-proliferative activity. However, the underlying mechanisms are still unknown. OBJECTIVE: This study determines the mechanisms of anti-proliferative activity induced by Annosquacin B (AB) against MCF-7/ADR cells...
July 22, 2016: Pharmaceutical Biology
Maria Harizani, Efstathia Ioannou, Vassilios Roussis
Nature, the most prolific source of biological and chemical diversity, has provided mankind with treatments for health problems since ancient times and continues to be the most promising reservoir of bioactive chemicals for the development of modern drugs. In addition to the terrestrial organisms that still remain a promising source of new bioactive metabolites, the marine environment, covering approximately 70% of the Earth's surface and containing a largely unexplored biodiversity, offers an enormous resource for the discovery of novel compounds...
2016: Progress in the Chemistry of Organic Natural Products
Marilza S Costa, Antônio E G Santana, Leandro L Oliveira, José E Serrão
BACKGROUND: The mosquito Aedes aegypti transmit virus that cause diverse human diseases and the vector control is an important strategy to avoid their propagation. Plants in Annonaceae are recognized as source to molecules with use in medical and agriculture fields. Molecules of secondary metabolites of Annonaceae plants exhibit insecticidal potential against insect pest and vectors, with highlight to acetogenins that show high toxicity with low doses, which encouraged research to producing new insecticide molecules...
July 1, 2016: Pest Management Science
H Konno, H Makabe, A Tanaka, T Oritani
The first synthesis of squamostanal-A (1), separated as a degradation product of tetrahydrofuranic acetogenins, is described. Iodide 7, which corresponds to the latent aldehyde moiety of 1, was prepared through a 2-step sequence from 13-[tetrahydropyran-2'- yloxy]-2-tridecyn-l-ol (5). The NaHMDS-based coupling reaction of 7 with γ-lactone 8 gave compound 9, which by a 3-step sequence, was coverted to 1.
January 1996: Bioscience, Biotechnology, and Biochemistry
Gordon J Florence, Andrew L Fraser, Eoin R Gould, Elizabeth F King, Stefanie K Menzies, Joanne C Morris, Marie I Thomson, Lindsay B Tulloch, Marija K Zacharova, Terry K Smith
Neglected tropical diseases caused by parasitic infections are an ongoing and increasing concern. They are a burden to human and animal health, having the most devastating effect on the world's poorest countries. Building upon our previously reported triazole analogues, in this study we describe the synthesis and biological testing of other novel heterocyclic acetogenin-inspired derivatives, namely 3,5-isoxazoles, furoxans, and furazans. Several of these compounds maintain low-micromolar levels of inhibition against Trypanosoma brucei, whilst having no observable inhibitory effect on mammalian cells, leading to the possibility of novel lead compounds for selective treatment...
July 19, 2016: ChemMedChem
Keerthana Prabhakaran, Gnanam Ramasamy, Uma Doraisamy, Jayakanthan Mannu, K Rajamani, Jayadeepa Rajamani Murugesan
BACKGROUND: Plants became the basis of traditional medicine system throughout the world for thousands of years and continue to provide mankind with new remedies. Annona muricata, the plant of Annonaceae family, is also known as sour sop or Graviola. In recent years, many compounds have been reported and have gained organic chemist's and biochemist's attention because of their novel structure and wide range of bioactivity. Local populations have used the bark, leaves, roots, fruit, seeds and flowers for thousands of years to treat everything from arthritis to liver problems...
May 31, 2016: Current Pharmaceutical Design
Natacha Bonneau, Isabelle Schmitz-Afonso, Alain Brunelle, David Touboul, Pierre Champy
Annonaceous acetogenins (AAGs) are environmental neurotoxins from the fruit pulp of several Annonaceae species, whose consumption was linked to the occurrence of sporadic atypical Parkinsonism with dementia. The quantification of the prototypical AAG annonacin in Rat brain homogenates was performed by UPLC-MS/MS in selected reaction monitoring (SRM) mode, using a triple quadrupole mass analyzer. A natural analog of annonacin was used as an internal standard. Analyzed data set of the analytical validation of this method is presented, including stability of the samples, extraction recovery and matrix effect, supporting the results described in the article "Quantification of the environmental neurotoxin annonacin in Rat brain by UPLC-MS/MS" N...
June 2016: Data in Brief
Masatoshi Murai, Hiroyuki Inaoka, Takahiro Masuya, Shunsuke Aburaya, Wataru Aoki, Hideto Miyoshi
Asp160 in the 49 kDa subunit of bovine mitochondrial complex I, which is located in the inner part of the quinone binding cavity, is considered to be an essential residue for energy conversion of the enzyme. To elucidate the catalytic function of this residue, we attempted to specifically methylate 49 kDa Asp160 [Asp(COO)-CH3] through a ligand-directed tosyl (LDT) chemistry technique with an acetogenin derivative (ALM) as a high-affinity ligand. We confirmed the specific methylation of 49 kDa Asp160 through liquid chromatography-tandem mass spectrometry analysis of the tryptic digests of the 49 kDa subunit...
June 14, 2016: Biochemistry
Jingyi Hong, Yanhong Li, Yao Xiao, Yijing Li, Yifei Guo, Haixue Kuang, Xiangtao Wang
Annonaceous acetogenins (ACGs) have exhibited antitumor activity against various cancers. However, these substances' poor solubility has limited clinical applications. In this study, hydroxypropyl-beta-cyclodextrin (HP-β-CD) and soybean lecithin (SPC) were self-assembled into an amphiphilic complex. ACGs nanosuspensions (ACGs-NSps) were prepared with a mean particle size of 144.4nm, a zeta potential of -22.9mV and a high drug payload of 46.17% using this complex as stabilizer. The ACGs-NSps demonstrated sustained release in vitro and good stability in plasma as well as simulated gastrointestinal fluid, and met the demand of both intravenous injection and oral administration...
September 1, 2016: Colloids and Surfaces. B, Biointerfaces
L P Ribeiro, J D Vendramim, M S Andrade, K U Bicalho, M F G F Silva, P C Vieira, J B Fernandes
The toxicity of organic plant extracts to Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) was assessed for three tropical plant species: branches, leaves, and seeds of Annona montana (Annonaceae), branches of Aristolochia paulistana (Aristolochiaceae), and leaves and branches of Casearia sylvestris (Salicaceae). The screening assay resulted that the extracts of A. montana seeds obtained with hexane (LC50 = 534.75 mg kg(-1) and LT50 = 6.10 days) and with dichloromethane (LC50 = 424...
October 2014: Neotropical Entomology
Ai Suzuki, Mai Sasaki, Tetsuya Nakagishi, Tsuyoshi Ueda, Naoyuki Hoshiya, Jun'ichi Uenishi
Cytotoxic acetogenin (+)-goniocin has been synthesized in 17 steps from (R)-O-tritylglycidol. The core structure of the contiguous C22-C10 threo-trans-threo-trans-threo-trans-tris-tetrahydrofuran (THF) ring involving an iterative THF-ring unit was synthesized. An iterative THF ring unit was constructed from an alkenyl-substituted THF ring in four steps including a Pd(II)-catalyzed ring-closing reaction and cross-metathesis. This method is general and allows the preparation of both trans-threo-trans- and trans-threo-cis-THF ring units flexibly...
May 6, 2016: Organic Letters
Priya Antony, Ranjit Vijayan
Apoptosis is a highly regulated process crucial for maintaining cellular homeostasis and development. The B-cell lymphoma 2 (Bcl-2) family of proteins play a crucial role in regulating apoptosis. Overexpressed Bcl-2 proteins are associated with the development and progression of several human cancers. Annona muricata is a tropical plant that belongs to the Annonaceae family and is well known for its anticancer properties. In this study, molecular docking and simulations were performed to investigate the inhibitory potential of phytochemicals present in A...
2016: Drug Design, Development and Therapy
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