[Studies on the alkaloids from stem of Artabotrys hainanensis].

Objective: To investigate the alkaloids from the stem of Artabotrys hainanensis.

Method: Compounds in plant extracts were separated by silica gel and sephadex LH-20 column chromatography. Chemical structures were elucidated by chemical and spectral analyses including UV, 1H-NMR, 13C-NMR, ESIMS and ESI-MS-MS.

[Determination on conditional equilibrium constants of the complexes of Gd(III) and Yb(III) with HBED by UV difference spectra].

In 0.01 mol x L(-1) Hepes, pH 7.4 and at room temperature the binding of HBED with Gd(III) or Yb(III) was monitored by UV difference spectrum.