Norditerpene dilactones from Podocarpus saligna

Rimuene and nubigenol have been identified in Podocarpus saligna for the first time, and the structures of three new norditerpene dilactones, salignones K, L and M, isolated from this species have been elucidated.     

The cytotoxic norditerpene dilactones of Podocarpus milanjianus and Podocarpus sellowii

The cytotoxic norditerpene dilactones nagilactone F and its new congener nagilactone G have been isolated from the bark constituents of Podocarpus milanjianus and Podocarpus sellowii. The diterpenes totarol, 19-oxototarol and macrophyllic acid were also isolated.     

The insecticidal activity of foliage from New Zealand conifers

When incorporated into artificial diets, the milled foliages of many New Zealand conifers are toxic to larvae of housefly (Musca domestica), codling moth (Laspeyresia pomonella) and light-brown apple moth (Epiphyas postvittana). The most toxic foliages are those of Podocarpus nivalis which contains diterpene lactones, and Dacrydium laxifolium, which has a high concentration (1%) of phytoecdysones. The insecticidal activities of the plants are discussed in relation to their insect associations, chemistry and taxonomy.     

Isocrotocaudin,A new norclerodane-type diterpene from Croton caudatus

Isocrotocaudin, a new furanoid norditerpene (norclerodane type), has been isolated from the petrol extract of the stem-bark of Croton caudatus (Eup     

Ent-labdanes from Mikania alvimii

The aerial parts of Mikania alvimii afforded in addition to known compounds seven new ent-labdane derivatives and a 15-nor compound. The struct     

Neue labdan- und pimaren-derivate aus Palafoxia rosea

The investigation ofPalafoxia rosea afforded in addition to known compounds five new labdane derivatives and five pimarene derivatives. The structures are elucidated by spectroscopic methods and some chemical transformations. The chemotaxonomic situation of the genus is discussed briefly.     

An antiproliferative norditerpene dilactone, Nagilactone C, from Podocarpus neriifolius

An ethanolic extract of Podocarpus neriifolius D. Don (Podocarpaceae) showed antiproliferative activity against two major tumor cell lines, viz. human HT-1080 fibrosarcoma and murine color 26-L5 carcinoma. Bioassay guided fractionation showed the highest antiproliferative activity in chloroform–soluble fraction. Nagilactone C, the major constituent of this fraction was isolated and characterized by using NMR, IR and FAB-MS spectroscopic methods. Nagilactone C possessed potent antiproliferative activity against human fibrosarcoma and murine colon carcinoma tumor cell lines exhibiting ED₅₀ values of 2.3 and 1.2 μg/ml, respectively. Hence, nagilactone C could be the active constituent present in this plant.     

A naphthalenic norditerpene from velloziaceae

The isolation of a new naphthalenic nor-cleistanthane diterpene from Vellozia epidendroides and V. phalocarpa is described.     

Biflavanoids,norditerpenes and a nortriterpene from Podocarp us urbanii

The structures of a biflavanoid, two new norditerpenes, urbalactone and 2,3-dihydropodolide, an ecdysterol, as well as a known biflavanoid, nagilactone C and podolide from Podocarpus urbanii were elucidated.     

Isolation and identification of two new biologically active norditerpene dilactones from Aspergillus wentii

Two new biologically-active norditerpenoid dilactones were purified from culture extracts of Aspergillus wentii and assigned the trivial names wentilactone A and wentilactone B. The absolute chemical structure of wentilactone A was determined by single crystal X-ray diffraction and circular dichroism. The structure of wentilactone B was determined by ¹H and ¹³C NMR analyses. Wentilactone A had an ld₅₀ of 7.0 mg/kg when administered orally to 1-day-old chickens. Both metabolites inhibited growth in wheat coleoptile bioassays.