Results 171 to 180 of about 3,863 (219)

Risk Assessment of Anatoxin-A

Revista Intertox de Toxicologia, Risco Ambiental e Sociedade, 2015
Current natural conditions as well as human activities have been promoting changes and increasing stress in the freshwater and marine environment. One of the consequences is the worldwide occurrence of cyanobacterial (blue-green algae) blooms, which is considered a serious environmental and economic problem (ARAOZ, et al 2005).
Vania Rodríguez, Ernani Pinto
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Dispersive magnetic immunoaffinity extraction. Anatoxin-a determination

Journal of Chromatography A, 2017
Specific monoclonal antibodies were coupled with magnetic Sepharose-based beads and used, for the first time. The methodology was applied to preconcentrate anatoxin-a from water and the later determination by ion mobility spectrometry (IMS). Dispersive magnetic immunoaffinity (d-MagIA) extraction methodology provided a limit of detection of 0.02μgL-1 ...
Tinh, Le, Francesc A, Esteve-Turrillas, Sergio, Armenta, Miguel, de la Guardia, Guillermo, Quiñones-Reyes, Antonio, Abad-Fuentes, Antonio, Abad-Somovilla   +6 more
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Homoanatoxin: A potent analogue of anatoxin-a

Biochemical Pharmacology, 1992
The natural toxin anatoxin-a (AnTx) is a potent nicotinic agonist that is valuable for the study of nicotinic receptors. We have synthesized 2-(propan-1-oxo-1-yl)-9-azabicyclo[4.2.1]non-2-ene, the homologue of AnTx in which the side-chain is extended by one methylene unit from a methyl to an ethyl ketone.
Wonnacott, S, Swanson, EL, Albuquerque, EX, Huby, NJS, Thompson, P, Gallagher, TC   +5 more
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Conformational studies on (+)-anatoxin-a and derivatives

Journal of Computer-Aided Molecular Design, 1992
Anatoxin-a (AnTX) is a highly potent agonist acting at the nicotinic acetylcholine receptor (nAChR) and represents a valuable tool in the study of this receptor. Molecular mechanics, semi-empirical and ab initio molecular orbital energy minimization procedures were conducted to investigate the conformation of AnTX.
P E, Thompson, D T, Manallack, F E, Blaney, T, Gallagher   +3 more
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Neurotoxic alkaloids: synthesis of (±)-anatoxin-a

J. Chem. Soc., Chem. Commun., 1987
Synthese a partir de tosylamino-2 heptadiene-5,6oate d'ethyle via l'ester d'ethyle de la tosyl-1 vinyl-5 proline et la tosyl-9 aza-9 bicyclo [4.2.1] nonanone ...
Peter Vernon, Timothy Gallagher
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ChemInform Abstract: Synthesis of Anatoxin‐a.

ChemInform, 1987
AbstractBromination of the azabicyclononanol (Ib) prepared from (Ia) gives the amino ketone (II) which is converted to N‐methylanatoxin‐a (Va) by abis‐homologation procedure using first Wittig‐Horner reaction with (III) and then an oxygenation/reduction step.
J. R. WISEMAN, S. Y. LEE
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Synthesis of (±)-Anatoxin-a and Analogues

Tetrahedron, 2000
A new and highly efficient synthesis of the potent nicotinic acetylcholine receptor agonist, anatoxin-a and its analogues is described, which uses a s-lactam ring opening-transannular cyclisation sequence to set up the bridged bicyclic framework of the natural product.
Philip J Parsons, Nicholas P Camp, Neil Edwards, L Ravi Sumoreeah   +3 more
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Anatoxin‐a occurrence and potential cyanobacterial anatoxin‐a producers in Spanish reservoirs¹

Journal of Phycology, 2007
The presence of anatoxin‐a (ANA) in Mediterranean region freshwaters has been reported only recently, and this work presents the first survey for ANA on a national scale in such waters. Fourteen reservoirs were sampled over a distance of 550 km from northeast to southwest Spain. Genera of cyanobacteria with ANA‐producing members in other countries were
David Carrasco, Enrique Moreno, Thamar Paniagua, Caridad de Hoyos, Lars Wormer, Daniel Sanchis, Samuel Cirés, Delia Martín‐del‐Pozo, Geoffrey A. Codd, Antonio Quesada   +9 more
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An efficient synthesis of (+)-anatoxin-a.

Tetrahedron: Asymmetry, 1992
Abstract An efficient synthesis (38 % overall yield in 8 steps starting from 2) of the potent neurotoxin (+)-anatoxin-a is described. The key step involves the stereoselective addition of 5-hexenylcopper to the chiral N-acyliminium ion 2a .
Marco Skrinjar, Carita Nilsson, Lars-G. Wistrand   +2 more
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Total Synthesis of Pinnamine and Anatoxin-a via a Common Intermediate. A Caveat on the Anatoxin-a Endgame

The Journal of Organic Chemistry, 2005
[reaction: see text] This paper describes the total synthesis of the naturally occurring alkaloids pinnamine (1) and anatoxin-a (2) from a common enantiomerically pure intermediate (7) easily available from pyroglutamic acid. The synthesis of enantiopure pinnamine proceeded in 10 steps and 4.8% overall yield, and the route was flexible enough to allow ...
Thomas, Hjelmgaard, Inger, Søtofte, David, Tanner   +2 more
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