The aim of this study was firstly to identify active molecules in herbs, that are traditionally used for the treatment of snake bite, such as Curcuma antinaia, Curcuma contravenenum, Andrographis paniculata, and Tanacetum parthenium; secondly to test similar structurally related molecules and finally to prepare and evaluate an efficient formulation against Ophiophagus hannah venom intoxificatio...

As part of our continuing efforts in the search for potential biologically active compounds from medicinal plants, we have isolated 18 compounds including two novel nitrogen containing diterpenes from extracts of the fruits of Vitex agnus-castus. These isolates, along with our previously obtained novel compound vitexlactam A (1), were evaluated for potential biological effects, including cancer...

Three new labdane diterpenoids, calomacrins A-C (1-3), and a new diaryl butyrolactone-type lignan, calomacrol A (8), as well as four known labdane diterpenoids and six known lignans, were isolated from the twigs and leaves of Calocedrus macrolepis. Structures of the new compounds were elucidated on the basis of their spectroscopic methods, including 1D and 2D NMR techniques. Compounds 3-14 were...

Eight ethanolic extracts of indigenous Taiwanese plants of the genus Alpinia were tested for tumor cytotoxicity against AGS, Hep G2, HeLa, KB, and HL-60 cells. Among the 50 % and 95 % EtOH extracts of eight Alpinia species, the cytotoxic effects of Alpinia intermedia leaves were the strongest. When the leaf extract of A. intermedia was partitioned using n-hexane and aqueous solvents, the n-hexa...

Two new diterpenes were isolated from stems and leaves of Xylopia langsdorffiana, ent-atisane-7alpha,16alpha-diol (xylodiol) and ent-7alpha-acetoxytrachyloban-18-oic acid (trachylobane), along with the known 8(17),12E,14-labdatrien-18-oic acid (labdane). We investigated their antitumour effects on HL60, U937 and K562 human leukemia cell lines. We found that xylodiol was the most potent diterpen...

Coronarin D is a labdane-type diterpene from the rhizomes of Hedychium coronarium. In the view of our ongoing effort to explore its novel biological activity, antimicrobial activity study of coronarin D was performed. The results showed that coronarin D was active against tested Gram-positive bacteria, inactive for tested Gram-negative bacteria, and weakly active against tested fungi. The antib...

To validate the potential as added-value resources of Asteraceae and Labiatae species of Argentinean semi-arid lands, we have selected 13 of their major terpenoids belonging to several chemical classes and tested their insect antifeedant and toxic activity on the herbivorous insects Spodoptera littoralis and Leptinotarsa decemlineata. The antifeedant effects of the test compounds were structure...

Three hundred and thirteen extracts from 136 Brazilian plant species belonging to 36 families were tested for their suppressive activity on phytohemaglutinin (PHA) stimulated proliferation of human peripheral blood mononuclear cells (PBMC). The proliferation was evaluated by the amount of [3H]-thymidine incorporated by the cells. Twenty extracts inhibited or strongly reduced the proliferation i...

Trinorlabdane 1,5-diketones (7, 10a,b, 13a,b), which are easily prepared from labdane diterpenes, are directly converted into the corresponding 7-oxo-13-hydroxy-8,11,13-podocarpatrienes, immediate precursors of bioactive compounds, under basic treatment. Utilizing this strategy, the first enantiospecific synthesis of 13-hydroxy-8,11,13-podocarpatriene (20), a constituent of Taiwania cryptomerio...