Results 121 to 130 of about 1,924 (168)

Mechanism of inhibition of cholinesterases by huperzine A

Biochemical and Biophysical Research Communications, 1992
Huperzine A, an alkaloid isolated from Huperzia serrata was found to reversibly inhibit acetylcholinesterases (EC 3.1.1.7) and butyrylcholinesterases (EC 3.1.1.8) with on- and off-rates that depend on both the type and the source of enzyme. Long-term incubation of high concentrations of purified cholinesterases (1-8 microM) with huperzine A did not ...
Y, Ashani, J O, Peggins, B P, Doctor
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A total synthesis of (±)-huperzine A

Tetrahedron Letters, 1989
Abstract The first total synthesis of (±)-huperzine A, a new lycopodium alkaloid is described.
Ligang Qian, Ruyun Ji
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Synthesis of (±)-desamino huperzine A

Tetrahedron Letters, 2000
The first synthesis of desamino huperzine A 2 is described. Key steps are a double Michael addition into benzoquinone monoketal 4, a regiocontrolled double bond isomerisation and a novel pyridone synthesis involving a Michael addition of a ß-keto ester into acrylonitrile. (C) 2000 Elsevier Science Ltd.
Högenauer, Klemens, Baumann, Karl, Mulzer, Johann   +2 more
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A Formal Synthesis of (+)-Huperzine A

Tetrahedron, 2000
Abstract A new formal stereoselective synthesis of (+)-Huperzine A (1) was achieved using as a key step a palladium mediated annulation between 2-methylene-1,3-propanediol diacetate and (1R,2S)-2-phenylcyclohexanol derived β-ketoester 2c.
Arnaud Haudrechy, Christophe Chassaing, Claude Riche, Yves Langlois   +3 more
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A combination of [+] and [−]-Huperzine A improves protection against soman toxicity compared to [+]-Huperzine A in guinea pigs

Chemico-Biological Interactions, 2013
The neuropathologic mechanisms after exposure to lethal doses of nerve agent are complex and involve multiple biochemical pathways. Effective treatment requires drugs that can simultaneously protect by reversible binding to the acetylcholinesterase (AChE) and blocking cascades of seizure related brain damage, inflammation, neuronal degeneration as well
Ying, Wang, Yanling, Wei, Samuel, Oguntayo, Bhupendra P, Doctor, Madhusoodana P, Nambiar   +4 more
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Huperzine A, a novel promising acetylcholinesterase inhibitor

NeuroReport, 1996
The effects of huperzine A on memory impairments induced by scopolamine were evaluated using a radial maze task and inhibition of cholinesterase in vitro compared with the effects of E2020 and tacrine. Scopolamine (0.2 mg kg-1) significantly impaired spatial memory in rats. Huperzine A (0.1-0.4 mg kg-1, p.o.), E2020 (0.5-1.0 mg kg-1, p.o.) and tacrine (
D H, Cheng, H, Ren, X C, Tang
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Role of Huperzine a in the Treatment of Alzheimer's Disease

Annals of Pharmacotherapy, 2009
Objective: To review the role of huperzine A in the treatment of Alzheimer's disease (AD). Data Sources: A literature search was conducted through MEDLINE (1950–September week 2, 2008), EMBASE (all years), Google Scholar, International
Alicia R, Desilets, Jennifer J, Gickas, Kaelen C, Dunican   +2 more
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Synthesis of 5-substituted analogues of huperzine A

Bioorganic & Medicinal Chemistry Letters, 2000
Three 5-isosteres of huperzine A (2-4) were first synthesized. The key intermediate 10 was prepared by the reaction of acid 13 with LTA. The compounds 2 and 3 had 50% inhibition by 35 and 47 microM, respectively, which still retained antiacetylcholinesterase activity.
G C, Zhou, D Y, Zhu
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Is There a Better Source of Huperzine A than Huperzia serrata? Huperzine A Content of Huperziaceae Species in China

Journal of Agricultural and Food Chemistry, 2005
A precise and selective reversed phase high-performance liquid chromatographic method was developed for quantifying huperzine A (HupA) in samples of the Huperziaceae in China. This method was used to quantify the levels of HupA in samples of Huperzia serrata collected from a single population at different times of the year, in different organs of the ...
Xiaoqiang, Ma, Changheng, Tan, Dayuan, Zhu, David R, Gang   +3 more
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Synthesis and acetylcholinesterase inhibition of derivatives of huperzine B

Bioorganic & Medicinal Chemistry Letters, 2005
AbstractFor Abstract see ChemInform Abstract in Full Text.
Song, Feng, Yu, Xia, Dongmei, Han, Chunyan, Zheng, Xuchang, He, Xican, Tang, Donglu, Bai   +6 more
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