Using an HBV-producing cell line and inhibition of the expression of the HBsAg and HBeAg as antiviral indicators, a study was conducted on 25 compounds isolated from four Phyllanthus (Euphorbiaceae) plants, including P. amarus Schum. & Thonn., P. multi florus Willd., P. tenellus Roxb. and P. virgatus Forst. f. It was found that niranthin (1), nirtetralin (3), hinokinin (5) and geraniin (13) at the non-cytotoxic concentration of 50 micro m, suppressed effectively both HBsAg and HBeAg expression, with the highest inhibition at 74.3%, 45.3%; 69.6%, 33.9%; 68.1%, 52.3%; 32.1%, 46.6%, respectively. Of these, niranthin (1) showed the best anti-HBsAg activity, while the most potent anti-HBeAg activity was observed with hinokinin (5).

d-Dicentrine was isolated from the root of Lindera megaphylla. It inhibited the aggregation of washed rabbit platelets induced by ADP, collagen, arachidonic acid, and PAF. It also inhibited the high potassium- and norepinephrine-induced contraction of rat thoracic aorta. In rat ventricular cells treated with 3 microM d-dicentrine, the action potential duration (ADP50) was prolonged from 59.9 +/- 11.3 msec to 201 +/- 28.7 msec.

Four new germacranolide sesquiterpenes, nepalolides A (2), B (3), C (4), and D (5a), and one known germacranolide, ineupatorolide A (1), were isolated from Carpesium nepalense. The structures of these new compounds were elucidated from spectral evidence and chemical transformation.

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The modular design of polyphosphines, diversely functionalized for facile immobilization on virtually any kind of support, is reported. Previously unobserved ABCD (31)P NMR spin-spin systems evidence the control exercised on the polyphosphines conformation. We illustrate the catalytic performance at low Pd loading of the recyclable immobilized polyphosphines in C-C bond formation reactions.