A known alkaloid (+)-chenabinol (1) and two new secobisbenzylisoquinoline alkaloids were isolated by standard chromatographic methods from the root bark of Berberis vulgaris L. The structures of the new alkaloids, named berkristine (2) and verfilline (3), were established by spectroscopic (including 2D NMR), and HRMS (ESI) methods. The alkaloids were tested for their inhibition activity of human cholinesterases and prolyl oligopeptidase. Compound 1 inhibited human butyrylcholinesterase with an IC50 value of 44.8 ± 5.4 μM.
JamesonCJ. (1991) The dynamic and electronic factors in isotope effects on NMR parameters. Isotopes in the Physical and Biomedical Sciences, 2, 1–49
3.
UllahS, ZhangW, HansenPE. (2010) Deuterium isotope effects on 13C and 15N chemical shifts of intramolecularly hydrogen-bonded enaminocarbonyl derivatives of Meldrum's and tetronic acid. Journal of Molecular Structure, 976, 377–391.
4.
HussainSF, SiddiquiMT, ShammaM. (1989) Berbidine: a simple isoquinoline-isoquinolone dimer. Journal of Natural Products, 52, 317–319.
5.
LeetJE, ElangoV, HussainSF, ShammaM. (1983) Chenabine and jhelumine: secobisbenzylisoquinolines or simple isoquinoline-benzylisoquinoline dimers?Heterocycles, 20, 425–429.
6.
WangYC, GeorghiouPE. (2002) First enantioselective total synthesis of (-)-tejedine. Organic Letters, 4, 2675–2678
