[A new antiviral isoquinoline alkaloid from Thalictrum glandulosissimum].

A new isoquinoline alkaloid(1) has been isolated from the whole plant of Thalictrum glandulosissimum by using various chromatographic techniques, including silica gel, sephadex, MCI-gel resin, and RP-HPLC, and its structure was determined as 1-(6-hydroxy-7-methylisoquinolin-1-yl) ethantone by physicochemical properties and spectroscopic data. This compound was evaluated for anti-tobacco mosaic virus(TMV) activity. The results showed that it had prominent anti-TMV activity with inhibition rates of 28.4%. This rate was closed to that of positive control.

[A new antimicrobial isobenzoisofuran compound from Cassia pumila].

A new isobenzoisofuran(1) has been isolated from the whole plant of Cassia pumila using various chromatographic techniques, including silica gel, Sephadex, MCI-gel resin, and RP-HPLC, and its structure was determined as 9-(2-hydroxyethyl)-2,2-dimethyl-2H-furo[3,4-g]chromen-6(8H)-one. This compound was also evaluated for its antibacterial activity. The results showed that it had prominent antibacterial activity with MIC_(90) value of(45.2±4.2) µg·mL~(-1) for methicillin resistant Staphylococcus aureus(MRSA) strain. This value was closed to that of levofloxacin [with MIC_(90) value(48.5±4.3) µg·mL~(-1)].

[A new cytotoxic flavone from Cassia nomame].

A new flavone( 1) has been isolated from the whole plant of Cassia nomame by using various chromatographic techniques,including silica gel,Sephadex,MCI-gel resin,and RP-HPLC,and its structure was determined as 8,4'-dimethoxy-7-( 2-oxopropyl)-flavone based on spectroscopic data. The biological activity test showed that this compound displayed potent cytotoxicity against NB4,SH-SY5 Y,PC3,A549 and MCF-7 cell lines with IC50 values 2. 2,1. 8,3. 4,4. 5 and 1. 6 µmol·L-1,respectively.

Two new biphenyls from the stems of Garcinia tetralata.

Two new biphenyls (1 and 2) and three known xanthones (3-5) were isolated from the ethanol extract of the stems of Garcinia tetralata. Structural elucidations of 1-2 were elucidated by spectroscopic methods including extensive 1D- and 2D-nuclear magnetic resonance spectroscopy techniques. Compounds 1-2 showed anti-rotavirus activities with SI above 10.

Anti-TMV activity flavones from the leaves of Yunnan local air cured tobacco.

Four new flavones, tobaflavones E-H (1-4), together with two known flavones (5 and 6), were isolated from the leaves of Dali Tiandeng tobacco (a variety of Yunnan local air cured tobacco). Their structures were elucidated by spectroscopic methods, including extensive 1D- and 2D NMR techniques. Compound 2 is the first naturally occurring flavone bearing a (4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methyl moiety. These compounds were also evaluated for their anti-tobacco mosaic virus (anti-TMV) activity. The results revealed that compounds 1 and 2 exhibited high anti-TMV activity with inhibition rate of 35.3% and 39.6%, respectively. The rates are higher than those of positive control. The other compounds also showed potential anti-TMV activity with inhibition rates in the range of 18.7-28.4%, respectively.

Five new prenylated chalcones from Desmodium renifolium.

Five unusual new prenylated chalcones, renifolins D-H (1-5), were isolated from whole Desmodium renifolium plants. All of their structures were determined by spectroscopic methods including 1D and 2D NMR. All of the isolates were evaluated for cytotoxicity using five tumor cell lines. Compounds 2 and 3 exhibited cytotoxicity against A549 cells, with IC50 values of 2.8 and 2.2 µM, respectively.

Isoflavanones from Desmodium oxyphyllum and their cytotoxicity.

Two new isoflavanones, (3R)-7-hydroxy-4'-methoxy-5-methoxycarbonyl-isoflavanone (1) and (3R)-8-hydroxy-4'-methoxy-7-methoxycarbonyl-isoflavanone (2), together with seven known isoflavanones (3-9) were isolated from Desmodium oxyphyllum of the Leguminosae family. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compound 1 showed good cytotoxicity against NB4 and SHSY5Y cell lines with IC50 values of 3.1 and 2.5 µM; compound 2 exhibited cytotoxicity against PC3 cell lines with a IC50 value of 3.6 µM; compound 4 showed cytotoxicity against A549 and SHSY5Y cell lines with IC50 values of 3.6 and 2.8 µM; and compound 5 displayed cytotoxicity against NB4, SHSY5Y, and MCF7 cell lines with IC50 values of 2.6, 3.8, and 2.8 µM, respectively. Other compounds also showed moderate cytotoxicity for some tested cell lines with IC50 values between 5.4 and 8.8 µM.

Cytotoxic deoxybenzoins and diphenylethylenes from Arundina graminifolia.

Eight new C-4-alkylated deoxybenzoins (1-8), three new diphenylethylenes (9-11), and five known diphenylethylenes were isolated from Arundina graminifolia. The structures of 1-11 were elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques. Compounds 9-11 are the first naturally occurring diphenylethylenes possessing a hydroxyethyl unit. Compounds 1-11 were evaluated for cytotoxicity against five human tumor cell lines. Compounds 4, 5, and 9-11 showed significant cytotoxicity against five cancer cell lines, with IC50 values ranging from 1.8 to 8.7 µM.

Dibenzocyclooctadiene lignans and norlignans from fruits of Schisandra wilsoniana.

Seven new dibenzocyclooctadiene lignans, marlignans M-S (1-7), four new norlignans, marphenols C-F (8-11), and 21 known compounds (12-32) were isolated from the fruits of Schisandra wilsoniana. The structures of 1-11 were elucidated by spectroscopic methods including 1D- and 2D-NMR techniques and CD experiments. Compounds 1-11 were evaluated for their anti-HIV activities and showed EC(50) values in the range 2.97-6.18 µg/mL and therapeutic index values of 5.33-29.13.

Dibenzocyclooctadiene lignans from the fruits of Schisandra wilsoniana and their anti-HIV-1 activities.

Three new dibenzocyclooctadiene lignans, wilsonilignans A-C (1-3), together with nine known ones, were isolated from the fruits of Schisandra wilsoniana. The structures of 1-3 were elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques. Compounds 1-3 were also evaluated for their anti-HIV-1 activities and showed bioactivity with EC(50) values of 3.26, 6.18, and 2.87 microg/ml, respectively.

Dibenzocyclooctadiene lignans from Schisandra wilsoniana and their anti-HIV-1 activities.

Twelve new dibenzocyclooctadiene lignans, marlignans A-L (1-12), together with 16 known compounds, were isolated from the leaves and stems of Schisandra wilsoniana. The structures of 1-12 were elucidated by spectroscopic methods including 1D- and 2D-NMR techniques. Compounds 1-12 were evaluated for their anti-HIV activities, of which compounds 3, 6, 8, and 12 showed modest activities with therapeutic index values of 13.2, 15.6, 17.6, and 16.4, respectively.