A new C(14) pterosin sesquiterpenoid, named (2R)-pterosin P (1), and a new natural product, named dehydropterosin B (3), were isolated from the aerial parts of Pteris multifida Poir., along with nine known compounds (2, 4-11). By chiral HPLC, compounds 1 and 2 were isolated as a pair of enantiomeric pterosin sesquiterpenoids. The planar structure of 1 was elucidated on the basis of NMR spectroscopy analysis, and the absolute configuration was established by the CD spectrum. In addition, the absolute structure of 1 was further confirmed by single-crystal X-ray diffraction (CuK α). Compounds 3, 5, and 6 showed potent cytotoxicity against PANC-1 (human pancreatic cancer) and NCI-H446 (human small-cell lung cancer) cell lines, with IC(50) values in the range of 4.27-14.63 µM.

Two new, i.e., 1 and 2, and 69 known phenolics were isolated from the aerial parts of Abies nephrolepis. These chemical constituents included 22 lignans, 30 flavonoids, and 19 other phenols. Their structures were determined mainly by analysis of the 1D- and 2D-NMR spectroscopic data. All the 71 isolates were evaluated for their inhibitory activities against lipopolysaccharide (LPS)-induced NO production in RAW 264.7 macrophages. Compound 1 exhibited a potent effect with an IC(50) value of 13.7 μg/ml.

No abstract

Three new pentacyclic triterpenoids, named centellasaponin I (1), centellasaponin J (2), and centellasaponin E (3), together with three known compounds, were isolated from the whole plants of Centella asiatica. Their structures were elucidated on the basis of chemical and spectral analysis, including 1D‐ and 2D‐NMR and HR‐MS experiments, and by comparison with literature data.

Phytochemical investigation of Eucommia ulmoides Oliver staminate flowers provided twenty-seven compounds, including 11 triterpenes (1 -11), 4 fatty acids (12 -15), 1 coumarin (16), 1 chromone (17), 7 flavonoids (18 -24) and 3 cyclopeptide alkaloids (25 -27). Compounds 4 -6, 8 -9, 11 -15, 17 and 25 -27 were reported for the first time in the genus Eucommia. Their structures were determined by nuclear magnetic resonance, mass spectroscopy, optical rotation, circular dichroism spectroscopy analyses and comparison with literature data. The anti-arthritic activity of these compounds was also evaluated in this study. The result showed 1, 2, 4, 9 and 14 could significantly inhibit proliferation of fibroblast-like synovial cells from rats with IC 50 values ranging from 11.83 -50.12 μM. Furthermore, the chemotaxonomic significance of the isolated compounds has also been discussed. 12 and 25 -27 might possess chemotaxonomic value for staminate flowers.