Title: Huperzine A
CAS Registry Number: 102518-79-6
CAS Name: [5R-(5a,9b,11E)]-5-Amino-11-ethylidene-5,6,9,10-tetrahydro-7-methyl-5,9-methanocycloocta[b]pyridin-2(1H)-one
Additional Names: selagine; HUP
Molecular Formula: C15H18N2O
Molecular Weight: 242.32
Percent Composition: C 74.35%, H 7.49%, N 11.56%, O 6.60%
Literature References: Reversible alkaloid inhibitor of AChE which crosses the blood-brain barrier. Occurs as the (-)-form in the vegetative part of clubmosses; teas brewed from these mosses have traditionally been used in China to alleviate memory problems. Isolated as selagine from Lycopodium selago L., Lycopodiaceae: J. Muszynski, Q. J. Pharm. Pharmacol. 21, 34 (1948); from Huperzia serrata as huperzine: Chin. Co-op Res. Group, J. Tradit. Chin. Med. 2, 45 (1982). Original structure: Z. Valenta et al., Tetrahedron Lett. 1960, 26; revised structure as huperzine A: J.-S. Liu et al., Can. J. Chem. 64, 837 1986. Identity with selagine: W. A. Ayer et al., ibid. 67, 1538 (1989). Synthesis of (±)-form: A. P. Kozikowski et al., J. Org. Chem. 56, 4636 (1991); G. Campiani et al., ibid. 58, 7660 (1993). NMR spectra: B. N. Zhou et al., Phytochemistry 34, 1425 (1993). HPLC determn in serum: J. Ye et al., J. Chromatogr. B 817, 187 (2005). Anticholinesterase activity: Y.-E. Wang et al., Acta Pharmacol. Sin. 7, 110 (1986); binding profile of enantiomers: M. McKinney et al., Eur. J. Pharmacol. 203, 303 (1991); binding specificity: Y. Ashani et al., Mol. Pharmacol. 45, 555 (1994). Clinical evaluation in senile dementia: R.-W. Zhang et al., Acta Pharmacol. Sin. 12, 259 (1991). Brief review of chemistry and clinical use: D. Bai, Pure Appl. Chem. 65, 1103-1112 (1993).
Properties: Monoclinic crystals from acetone, mp 214-215°. [a]D -147° (c = 0.36 in CH3OH) (Ayer). Also reported as mp 230°. [a]D24.5 -150.4° (c = 0.498 in MeOH) (Liu). uv max (EtOH): 231, 313 nm (log e 4.01, 3.89).
Melting point: mp 214-215°; mp 230°
Optical Rotation: [a]D -147° (c = 0.36 in CH3OH) (Ayer); [a]D24.5 -150.4° (c = 0.498 in MeOH) (Liu)
Absorption maximum: uv max (EtOH): 231, 313 nm (log e 4.01, 3.89)
Therap-Cat: In treatment of memory disorders. |