Huperzine anticholinesterase

Alcala MDM, Vivas NM, Hospital S, et ai. Characterisation of the anticholinesterase activity of two new tacrine-huperzine A hybrids, Neuropharmacol... 

Anticholinesterases E.g. physostigmine, tacrine, donepezil, metrifonate, huperzine A, eptastigmine, velnacrine, galantamine, rivastigmine Efficacy in early stages of AD... 

Laganiere, S. Corey, J. Tang, X. C. Wulfert, E. Hanin, I. Acute and chronic studies with the anticholinesterase huperzine A effect on central nervous system cholinergic parameters. Neuropharmacology, 1991, 30 763-768. 

Campiani, G. Kozikowski, A. R Wang, S. Ming, L. Nacci, V. Saxena, A. Doctor, B. P. Synthesis and anticholinesterase activity of huperzine A analogues containing phenol and catechol replacements for the pyridone ring. Bioorg. Med. Chem. Lett., 1998, 8(11) 1413-1418. 

Kozikowski, A. R Campiani, G., Nacci, V., Sega, A., Saxena, A., Doctor, B. P. An approach to modified heterocyclic analogues of huperzine A and isohuperzine A. Synthesis of the pyrimidone and pyrazole analogues, and their anticholinesterase activity. J. Chem. Soc. Perkin Trans. 1, 1996, 11 1287-1297. 

Neurotransmitter inactivation. A number of animal and plant agents act as ANTICHOLINESTERASES, so interfering with synaptic trasmission. These include fasciculins (Fasl, Fas2, FasS), which are peptide snake venoms, huperzine from a plant, onchidal from molluscs and physostigmine (eserine) from the calabar bean. 

Huperzine A, a potent anticholinesterase alkaloid, and huperzine B were separated from a Chinese medicinal herb, Huperzia serrata (Thunb) Trev. Lycopodium serratum Thunb.), (Lycopodiaceae), by Liu et al [25]. The plant was used in Zhejiang Province of China for treatment of some mental disorders. 

Huperzine B has a molecular formula of C16H20N2O, m.p. 270-271 °C, [cx]d-54.2° (C, 0.2, MeOH). It has UV spectrum absorptions at Amax (log e) 231 (3.95), 312 (3.85), and IR spectrum absorptions at vmax 3100, 1670, 1620,1610,1560 cm-1. The whole structure was proposed by spectral analyses as shown in 5-3. Its main difference from huperzine A is the absence of exocyclic double bond which form an additional piperidine ring in 5-3. Huperzine B does not possess anticholinesterase activity. 

P2. Patocka, J., Huperzine A—An interesting anticholinesterase compound from the Chinese herbal medicine. Acta Med.fHradec Kralove) 41, 155-157 (1998). 

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