To study the chemical constituents of Nervilia fordii (Hance) Schltr., various chromatographic methods were used, including D101 macroporous resin, silica gel, ODS and preparative HPLC chromatographic techniques. A new labdane diterpenoid glycoside named as nervilifordoside A was isolated from 60% EtOH extract of Nerviliafordii. The structure of compound 1 was elucidated as 12, 17-epoxy-3-hydroxy-17-methoxy-labdan-13-en-16, 15-olide 3-O-alpha-rhamnopyranosyl-(1 --> 2)-O-beta-glucopyranoside on the basis of HR-MS, 1D and 2D NMR spectroscopic data as well as chemical methods.

The inhibition effects of the extracts of five Verbenaceae herbs, Clerodendrum fortunatum L. , Clerodendrum japonicum(Thunb. )Sweet, Clerodendrum philippinum Schauer var. simplex Moldenke, Callicarpa longissima(Hemsl. )Merr. and Pygmaeopremna herbacea, were investigated by cell hemolysis model in vitro on classical and alternative complement activation pathways. The water extracts of Pygmaeopremna herbacea, the water extract and the ethanol extract of Clerodendrum fortunatum L. , the water extract and the ethanol extract of Callicarpa longissima(Hemsl. )Merr. , the ethanol extracts of Clerodendrum japonicum(Thunb. )Sweet and Clerodendrum philippinum Schauer var. simplex Moldenke showed inhibition cell hemolysis effects on the classical pathway. Their CH50 values were 0. 092±0. 008, 0. 074±0. 008, 0. 088±0. 006, 0. 134±0. 017, 0. 123±0. 010, 0. 380±0. 080, and 0. 200±0. 015 g/L, respectively. The water extracts of Pygmaeopremna herbacea and Callicarpa longissima(Hemsl. )Merr. and the ethanol extract of Clerodendrum fortunatum L. showed inhibition cell hemolysis effects on alternative pathway. Their AP50 values were 0. 533±0. 033, 0. 758±0. 031, and 0. 362±0. 029 g/L, respectively. Five Verbenaceae herbs appear good anticomplementary effects in vitro. The ethanol extract of Clerodendrum fortunatum L. showed the best inhibitory activity.