Shi Kai Yan

Japonicones A-D, bioactive dimeric sesquiterpenes from Inula japonica Thunb.

Four new dimeric sesquiterpene lactones japonicones A-D (1-4), comprised by eudesmane and guaiane sesquiterpenes, were isolated from the aerial part of Inula japonica Thunb. The structures and stereochemistry of 1-4 were elucidated by use of 2D NMR spectroscopic techniques, X-ray crystallography and modified Mosher method. Japonicone A (1) showed the most potent cytotoxicities against four tumor cell lines, A549, LOVO, CEM and MDA-MB-435.

Japonicones E-L, dimeric sesquiterpene lactones from Inula japonica Thunb.

Eight new dimeric sesquiterpene lactones (japonicones E-L, 1- 8), including a novel sesquiterpene dimer bearing a rare hydroperoxide group (japonicone E, 1), were isolated from the aerial part of Inula japonica Thunb. Their structures were determined mainly by the use of 1D and 2D NMR spectroscopic techniques including HSQC, (1)H-(1)H COSY, HMBC, and NOESY. All the isolates were tested for inhibitory effects against LPS-induced NO production in RAW264.7 macrophages. Among the compounds tested, japonicone F (2) showed the strongest activity with the IC(50) value of 4.1 microg/mL.

Phenylpropanoids and lignanoids from Euonymus acanthocarpus

A new phenylpropanoid derivative (1), along with five phenylpropanoids (2–6), two monoepoxy lignans (8–9), one bisepoxy lignan (10), two cyclolignans (11–12), six neolignans (7, 13–17), two mixed lignan-neolignans (18–19), two lignan glycosides (20–21), and four flavonolignans (22–25), were isolated from the stems and twigs of Euonymus acanthocarpus. Compounds 2–3, 6–8, 12, and 14–25 were obtained from Celastraceae family for the first time, and compounds 5 and 9 were isolated from Euonymus genus for the first time. All the compounds were tested for cytotoxicity against SK-OV-3 and MCG-803 human tumor cell lines. Compounds 3, 10, 12, and 18 showed weak cytotoxicity against SK-OV-3 cell line, and compounds 3–4, 10–13, and 19 showed weak cytotoxicity against MCG-803 cell line.

Flavonoids from Rhododendron decorum

wdzhangy@hotmail.com; 2) School of Life Science and Pharmaceutical Engineering, NanJing University of Technology, Nanjing 210009, P. R. China; 3) JiangXi University of Traditional Chinese Medicine, Key Laboratory of Modern Chinese Preparation, Ministry of Education, Nanchang 330004, P. R. China; 4) Department of Phytochemistry, Second Military Medical University, Shanghai 200433, P. R. China. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 75-76, January-February, 2009. Original article submitted July 12, 2007.

A new triterpenoid from Brucea javanica

A new triterpenoid, bruceajavanin C (1), together with bruceosides A and B (2 and 3), bruceines D and E (4 and 5), yadanziosides A and G (6 and 7), (20R)-O-(3)-α-L-arabinopyranosylpregn-5-ene-3β,20-diol (8), and α-D-glucopyranoside, (3β, 20R)-3-hydroxypregn-5-en-20-yl (9) were isolated from the aerial parts of Brucea javanica. The structure of 1 was elucidated on the basis of 2D-NMR spectroscopic analysis. In addition, compounds 1, 3, 4, 5, and 6 exhibited mild inhibitory effect on NO production in LPS-stimulated RAW264.7 cells.

A new chromone glycoside from Rhododendron spinuliferum

A new chromone glycoside, 3,5,7-trihydroxylchromone-3-O-α-L-arabinopyranoside (1), together with quercetin (2), (+)-catechin (3), (−)-epi-catechin (4) were isolated from the aerial parts of Rhododendron spinuliferum. The structure of 1 was elucidated on the basis of spectroscopic and 2D-NMR spectral analysis. In addition, 1 exhibited mild inhibitory effect on NO production in LPS-stimulated RAW264.7 cells.

Five new sesquiterpene lactones from Inula hupehensis.

Four new pseudoguaianolides (1–4), one new guaianolide (5), together with ten known compounds (6–15) were isolated from the aerial parts of Inula hupehensis. Their structures were elucidated mainly on the basis of 1D and 2D spectroscopic methods and circular dichroism analysis. In addition, compounds 1–10 and 13 were tested for their inhibitory effects against LPS-induced NO production in RAW264.7 macrophages. Compounds 2, 6, 8 and 9 exhibited significant inhibitory activities with IC50 values in the range of 0.6–6.6xa0μM.

A new grayanane diterpenoid from Rhododendron decorum

A new grayanane diterpenoid, 2,3-epoxy-5beta,6beta,10alpha,13beta,16alpha-pentahydroxy-grayanane, named craiobiotoxin IX (1), together with the known grayanotoxins I and IV, was isolated from the aerial part of Rhododendron decorum. The structure was elucidated on the basis of spectroscopic and X-ray diffraction analysis.