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Philotheca sect. Erionema includes 14 species from eastern Australia and one from south-western Australia. We conducted a phylogenetic analysis of the section, including samples of all species, using sequences of the ITS and ETS regions of nuclear ribosomal DNA. Results were broadly congruent with a previous analysis based on morphological and flavonoid data. The analysis is consistent with the monophyly of the section and supports the monophyly of six species represented by multiple samples. Philotheca verrucosa (A. Rich.) Paul G. Wilson was resolved as paraphyletic with respect to P. freyciana Rozefelds but with poor support. Philotheca glasshousiensis, P. myoporoides and P. myoporoides subsp. myoporoides were clearly polyphyletic, including separate geographic clades and the classification of each of these taxa requires revision. In particular, disjunct northern populations of P. glasshousiensis probably represent a distinct species, the five subspecies of P. myoporoides could be treated as separate species and at least two other distinct groups that are currently included under the circumscription of subsp. myoporoides could be treated as species. The phylogeny revealed deeply divergent, geographically overlapping clades in eastern Australia and substantial distances (up to 900 km) between sister taxa. We infer that biogeography of the group has been shaped largely by vicariant differentiation of taxa.

Four new alkaloids, (R)-nomimantharine trifluoroacetate (2), 12-demethylphaeantharine trifluoroacetate (3), nominanthranal trifluoroacetate (4), and the enolic form of 1-hydroxy-6,7-dimethoxy-2-methylisoquinoline trifluoroacetate (5), together with the known dimeric alkaloid phaeantharine trifluoroacetate (1), have been isolated from the extract of the leaves of the rainforest tree Doryphora aromatica (Monimiaceae). The structures of these compounds were elucidated by HRMS and 1D and 2D NMR data. (R)-Nomimantharine trifluoroacetate (2) contains an ether linkage connecting a benzylisoquinoline unit with a tetrahydroisoquinoline, a novel class of dimeric alkaloid. The absolute configuration of (R)-nomimantharine trifluoroacetate (2) was established via electronic circular dichroism data. The compounds isolated were subjected to in vitro antimicrobial assays against a panel of pathogenic microorganisms, including Mycobacterium smegmatis, M. tuberculosis, Escherichia coli, Staphylococcus aureus (SA), and five clinical isolates of oxacillin/methicillin-resistant S. aureus (MRSA). Phaeantharine trifluoroacetate (1) and (R)-nomimantharine trifluoroacetate (2) showed moderate inhibitory activities against Mycobacteria and MRSA strains.

As part of a continuing research program aiming to identify chemical probes to interrogate Parkinson's disease (PD), we have investigated the Australian plants Gloriosa superba and Alangium villosum. The chemical investigations of G. superba resulted in the isolation of four new alkaloids, β-lumicolchicosides A-C (1-3) and γ-lumicolchicoside A (4), together with four lumicolchicine derivatives (5-8) and six colchicine analogues (9-14) as known structures. The chemical investigations of A. villosum resulted in the isolation of four new benzoquinolizidine N-oxides, tubulosine Nβ5-oxide (15), isotubulosine Nα5-oxide (16), 9-demethyltubulosine Nβ5-oxide (17), and 9-demethylisotubulosine Nα5-oxide (18), together with five known benzoquinolizidine alkaloids (19-23). The chemical structures of the new compounds (1-4 and 15-18) were characterized unambiguously by extensive analysis of their NMR and MS data. Unbiased multidimensional profiling was used to investigate the phenotypic profiles of all of the metabolites. The results show that the lead probes have different effects on cellular organelles that are implicated in PD in patient-derived cells.

A synopsis of the genera Coleus Lour, Equilabium A.J.Paton, Mwany. & Culham and Plectranthus L’Hér. (Lamiaceae, Tribe Ocimeae, Subtribe Plecranthinae) is presented. Generic delimitation follows a recently published molecular phylogeny which identified Coleus as the sister of the remaining genera of Subtribe Plectranthinae; Plectranthus as sister to Tetradenia Benth. and Thorncroftia N.E.Br., and a separate phylogenetically distinct genus Equilabium comprising species previously placed in Plectranthus. In this treatment, 294 species of Coleus, 42 of Equilabium, and 72 of Plectranthus are recognized. All but one of the combinations in Equilabium are new as only the genus and type species have been previously published. Two-hundred and twelve names are changed to combinations in Coleus from Plectranthus, Pycnostachys Hook. and Anisochilus Benth.

Four new alkaloids, (R)-nomimantharine trifluoroacetate (2), 12-demethylphaeantharine trifluoroacetate (3), nominanthranal trifluoroacetate (4), and the enolic form of 1-hydroxy-6,7-dimethoxy-2-methylisoquinoline trifluoroacetate (5), together with the known dimeric alkaloid phaeantharine trifluoroacetate (1), have been isolated from the extract of the leaves of the rainforest tree Doryphora aromatica (Monimiaceae). The structures of these compounds were elucidated by HRMS and 1D and 2D NMR data. (R)-Nomimantharine trifluoroacetate (2) contains an ether linkage connecting a benzylisoquinoline unit with a tetrahydroisoquinoline, a novel class of dimeric alkaloid. The absolute configuration of (R)-nomimantharine trifluoroacetate (2) was established via electronic circular dichroism data. The compounds isolated were subjected to in vitro antimicrobial assays against a panel of pathogenic microorganisms, including Mycobacterium smegmatis, M. tuberculosis, Escherichia coli, Staphylococcus aureus (SA), and five clinical isolates of oxacillin/methicillin-resistant S. aureus (MRSA). Phaeantharine trifluoroacetate (1) and (R)-nomimantharine trifluoroacetate (2) showed moderate inhibitory activities against Mycobacteria and MRSA strains.

As part of a continuing research program aiming to identify chemical probes to interrogate Parkinson's disease (PD), we have investigated the Australian plants

Two new species of Plectranthus are described from Cape York Peninsula, Queensland. Plectranthus amiculatus and P. altanmouiensis have restricted distributions on the peninsular tip and Altanmoui range, respectively. Both species are illustrated and notes on habitat, distribution, affinities and conservation status are provided.

Premise of research. Rain forest ecosystems globally are synonymous with biodiversity, yet these vegetation communities vary widely in structure and composition. Historical biogeography and environment are thought to have significantly impacted Australian rain forest diversity and composition. Rain forest in Australia is extensively fragmented, and detailed vegetation mapping is used as a tool for conservation and land management planning. In Queensland, a regional ecosystem (RE) vegetation classification scheme is used by land managers. However, there has been no assessment to date of how evenly rain forest RE types are conserved at a regional scale, whether those conserved are the best representatives of biodiversity, and whether there are significantly distinctive RE types that are relatively poorly conserved or not recognized for their significance to biodiversity conservation.Methodology. Our phylogeny for South East Queensland (SEQ) rain forest species, which encompasses 95% of rain forest species b...

The aerial parts of the endemic Australian plant Eremophila debilis (Myoporaceae) contain 3% dry weight of the biologically active 5,6,7,3',4',5'-hexamethoxyflavone, which had its structured confirmed using X-ray crystal crystallography. The presence of significant levels of the polypharmacologically active 5,6,7,3',4',5'-hexamethoxyflavone in the edible parts of the plant has potential implications for its use as a food and bush medicine.

Funding for this work was provided by a University of Washington Royalty Research Fund Grant (R.B.), National Science Foundation Graduate Research Fellowship DGE‐1256082 (M.A.K.), and German Research Foundation (DFG) Fellowship GE2558/3‐1 (M.M.G). Cyanobiont collection was funded by grant no. 265‐605 of the Australian Biodiversity and Resources Programme (M.M.G). Molecular nitrogen (N2) constitutes the majority of Earth's modern atmosphere, contributing ~0.79 bar of partial pressure (pN2). However, fluctuations in pN2 may have occurred on 107–109 year timescales in Earth's past, perhaps altering the isotopic composition of atmospheric nitrogen. Here, we explore an archive that may record the isotopic composition of atmospheric N2 in deep time: the foliage of cycads. Cycads are ancient gymnosperms that host symbiotic N2‐fixing cyanobacteria in modified root structures known as coralloid roots. All extant species of cycads are known to host symbionts, suggesting that this N2‐fixing capacity is perhaps ancestral, reaching back to the early history of cycads in the late Paleozoic. Therefore, if the process of microbial N2 fixation records the δ15N value of atmospheric N2 in cycad foliage, the fossil record of cycads may provide an archive of atmospheric δ15N values. To explore this potential proxy, we conducted a survey of wild cycads growing in a range of modern environments to determine whether cycad foliage reliably records the isotopic composition of atmospheric N2. We find that neither biological nor environmental factors significantly influence the δ15N values of cycad foliage, suggesting that they provide a reasonably robust record of the δ15N of atmospheric N2. Application of this proxy to the record of carbonaceous cycad fossils may not only help to constrain changes in atmospheric nitrogen isotope ratios since the late Paleozoic, but also could shed light on the antiquity of the N2‐fixing symbiosis between cycads and cyanobacteria. Postprint

A synopsis of the genera Coleus Lour, Equilabium A.J.Paton, Mwany. & Culham and Plectranthus L’Hér. (Lamiaceae, Tribe Ocimeae, Subtribe Plecranthinae) is presented. Generic delimitation follows a recently published molecular phylogeny which identified Coleus as the sister of the remaining genera of Subtribe Plectranthinae; Plectranthus as sister to Tetradenia Benth. and Thorncroftia N.E.Br., and a separate phylogenetically distinct genus Equilabium comprising species previously placed in Plectranthus. In this treatment, 294 species of Coleus, 42 of Equilabium, and 72 of Plectranthus are recognized. All but one of the combinations in Equilabium are new as only the genus and type species have been previously published. Two-hundred and twelve names are changed to combinations in Coleus from Plectranthus, Pycnostachys Hook. and Anisochilus Benth.

An analytical method using UHPLC-MS was developed and applied to 16 crude CH2Cl2 extracts from Australian Celastraceae plants, the endemic plant materials were accessed from Griffith University&rsquo, s NatureBank resource and included bark, fruit, leaf, root, twig and mixed samples, all of which were collected from Queensland, Australia. The generated UHPLC-MS data were analysed and dereplicated using the scientific databases Dictionary of Natural Products and SciFinder Scholar in order to potentially identify new dihydro-&beta, agarofurans from local Celastraceae plants. These investigations led to the large-scale extraction and isolation work on a prioritised fruit sample that belonged to the rainforest plant Denhamia celastroides. Chemical investigations resulted in the purification of four new natural products, denhaminols O&ndash, R (1&ndash, 4), along with the related and known compound, denhaminol G (5). The structures of all the new compounds were determined via detailed analysis of NMR and MS data.

International audience; Halfordia F.Muell is a genus of rainforest trees or shrubs native to New Guinea, New Britain, New Caledonia, Vanuatu and eastern Australia. There is debate about the number of species that should be recognised in the genus. Four species have been named, but authors have commonly recognised only two species, and some recent treatments accept just one widespread species with a broad ecological range. We sequenced two nrDNA markers (ITS and ETS) and two cpDNA markers (rbcL and trnL–trnF) from samples across the range of Halfordia in Australia and New Caledonia. Three allopatric nrDNA groups were resolved: one from southeast Queensland and northern New South Wales (Group A); one from the Wet Tropics region of North Queensland (Group B); and one from the Cape York region of North Queensland, Torres Strait and New Caledonia (Group C). These groups were also partly differentiated by more slowly evolving cpDNA markers; the exception was one widespread haplotype in Australia (presumed ancestral). The nrDNA groups support recognition of three previously described species: H. leichhardtii (Group A), H. scleroxyla (Group B) and H. kendack (Group C). Divergences among eastern Australia populations are best explained by vicariance and correlate with geographic breaks documented for other taxa (ranging in estimated ages from the mid-late Miocene to the Pleistocene). The broad distribution of Group C, from Cape York to New Caledonia, with less genetic divergence, arguably reflects recent range expansion into New Caledonia involving bird dispersal of fleshy fruits.

The leaf essential oils of Micromelum minutum, Clausena brevistyla and C. smyrelliana, all growing in Australia, have been investigated. M. minutum gave an oil in which the major components were the sesquiterpenes δ-elemene (3.3–18.6%), β-caryophyllene (4.8–30.3%), germacrene-D (2–15.8%) and germacrene-B (3.9–34.3%).C. brevistyla gave an oil rich in monoterpenes in two cases and sesquiterpenes in a third case. The principal components were myrcene (72.4%) or limonene (83.3%) for the monoterpene varieties and β-caryophyllene (19.4%), α-humulene (4.3%), bicyclogermacrene (9.5%), caryophyllene oxide (7.6%) and spathulenol (10.6%) for the sesquiterpene variety. C. smyrelliana gave an oil which was monoterpenic in nature with the principal component being α-pinene (73.3%), with β-caryophyllene (8.5%) as the next most abundant component.

As part of an investigation of the more primitive plant families in Australia the chemical profile of the essential oils from leaves of the six species of the Australian genus Daphnandra have been characterized. Daphnandra apetala gave a sesquiterpenic oil, with β-caryophyllene (9–19%), germacrene-D (15–20%) and bicyclogermacrene (9–12%) constituting the major components. D. johnsonii gave an oil with significant amounts of monoterpenes (α-pinene, 31.7% and camphene, 18.6%) and sesquiterpenes (cubenol, 3.1%, β-caryophyllene, 3.1% and α-, β-, γ-eudesmols, 6.3%, 5.1%, 2.3%, respectively). D. melasmena produced sesquiterpenic oil, with spathulenol (20.4%) and bicyclogermacrene (8.3%) as the principal components. D. micrantha produced a oil with sesquiterpenes (mainly cubebol, 7.4%, spathulenol, 8.3% and germacrene-D, 6.8%) and monoterpenes (mainlyα-pinene, 8.5%, camphene, 8.6%) as the most significant components. D. repandula gave a sesquiterpenic oil of two types; one in which the principal componen...

The genus Flindersia (Rutaceae) comprises 17 species of mostly Australian endemic trees. Although most species are restricted to rainforests, four have evolved to grow in semi-arid and arid environments. In this study, the leaf alkaloid diversity of rainforest and semi-arid/arid zone adapted Australian Flindersia were compared by LC/MS-MS and NMR spectroscopy. Contrary to expectations, Flindersia alkaloid diversity was strongly correlated with environmental aridity, where species predominating in drier regions produced more alkaloids than their wet rainforest congenerics. Rainforest species were also more chemically similar to each other than were the four semi-arid/arid zone species. There was a significant relationship between the presence of alkaloid structural classes and phylogenetic distance, suggesting that alkaloid profiles are influenced by both genetic and environmental factors. The results suggest that the radiation of Flindersia species out of the rainforest and into drier environments has promoted the evolution of unique alkaloid diversity. Plants growing in arid and semi-arid regions of Australia may represent an untapped source of undescribed specialised metabolites.

Mass-directed isolation of the CH2Cl2/MeOH extract from the bark of an Australian plant, Macropteranthes leichhardtii, resulted in the purification of a new phenylpropanoid glucoside, macropteranthol (1), together with four known analogues (2-5). The structure of compound 1 was elucidated by NMR and MS data analyses and quantum chemical calculations. Compounds 3 and 5 showed inhibitory activity against tyrosyl-DNA phosphodiesterase I with IC50 values of ∼1.0 μM.

The rainforest genus Gossia N.Snow & Guymer (Myrtaceae) occurs in Australia, Melanesia and Malesia, and is capable of hyperaccumulating the heavy metal manganese (Mn). Here, we used nuclear ribosomal and plastid spacer DNA-sequence data to reconstruct the phylogeny of 19 Australian species of Gossia and eight New Caledonian taxa. Our results indicated that the relationship between Gossia and Austromyrtus (Nied.) Burret is not fully resolved, and most Australian species were supported as monophyletic. Non-monophyly might be related to incomplete lineage sorting or inaccurate taxonomic classification. Bark type appears to be a morphological synapomorphy separating two groups of species, with more recently derived lineages having smooth and mottled ‘python’ bark. New Caledonian species were well resolved in a single clade, but were not the first diverging Gossia lineage, calling into doubt the results of a recent study that found Zealandia as the ancestral area of tribe Myrteae. Within Australia, the evolution of multiple clades has probably been driven by well-known biogeographic barriers. Some species with more widespread distributions have been able to cross these barriers by having a wide range of soil-substrate tolerances. Novel Mn-hyperaccumulating species were identified, and, although Mn hyperaccumulation was not strongly correlated with phylogenetic position, there appeared to be some difference in accumulation levels among clades. Our study is the first detailed phylogenetic investigation of Gossia and will serve as a reference for future studies seeking to understand the origin and extent of hyperaccumulation within the Myrteae and Myrtaceae more broadly.

Two new species of Plectranthus L’Hér. are described from tropical Queensland. Both Plectranthus laxus T.C.Wilson & P.I.Forst. and P. wallamanensis T.C.Wilson & P.I.Forst. are perennial suffrutescent shrubs found in open, exposed rocky habitats in the Wet Tropics bioregion. Both species are illustrated and notes on habitat, distribution, affinities and conservation status are provided. A revised key for Plectranthus in Queensland and the Australian tropics is presented.

 Premise of the study: Plants that strongly accumulate metals may be practically benefi cial, and also serve as novel resources for increasing fundamental understanding of plant biology. Australian Gossia (Myrtaceae) species are delineated by a conspicuous affi nity for the heavy metal manganese (Mn), which is a micronutrient crucial to photosynthesis. This genus includes several Mn hyperaccumulators such as G. bidwillii . Unusually, in G. bidwillii foliar Mn is most highly concentrated in photosynthetic cells, an observation thus far restricted to foliar-Mn accumulation in Mn hyperaccumulators. Recent discovery that several of these Gossia species accumulate other metals in addition to Mn will enable investigation as to whether primary sequestration of metals in photosynthetic tissues is restricted to Mn.  Methods: Gossia species known to accumulate nickel (Ni) or aluminum (Al) in addition to Mn were sampled in the fi eld. Complementary proton- and electron-probe data were combined to evaluate in vivo microdistribution patterns of excessively accumulated foliar metals.  Key results: It was discovered that in addition to Mn and Ni, Gossia fragrantissima accumulated foliar zinc (Zn) and cobalt (Co), with Mn, Ni, and Co most highly localized in mesophyll cells and Zn primarily located in the upper epidermis. In G. hillii , Mn and Al were highly concentrated in the palisade and epidermis, respectively.  Conclusions: This investigation provides evidence that the primary disposal of excess foliar metals in photosynthetic cells is not exclusive to Mn. It offers rare intrageneric perspective on metal compartmentation, pointing to signifi cant variation among tonoplastal metal transporters associated with detoxifi cation.

Three new β-triketones, watsonianones A-C, and the known compound corymbone B were isolated from the flowers of the Australian eucalypt Corymbia watsoniana. Watsonianone A is the first naturally occurring methylene bridged bis-tetramethylcyclohexatrione, watsonianone B is only the fourth fused bisfurano β-triketone and watsonianone C is the first 4,4a,9,9a-tetrahydro-2H-xanthene-1,3,5,7(6H,8H)-tetraone to be reported in the literature. MS and NMR analysis established the structures of the new compounds. All three new compounds showed anti-plasmodial activity against chloroquine resistant (Dd2) and sensitive strains (3D7) of the parasite, Plasmodium falciparum, responsible for malarial infections. Watsonianone B was the most potent inhibitor (IC(50) 0.289 μM vs. Pf 3D7) demonstrating significant selectivity against the human cell line, HEK 293 (400 ×). Stage specificity studies indicate that watsonianone B is predominantly active against young ring stages of P. falciparum.

The sole species of the vascular plant family Austrobaileyaceae, Austrobaileya scandens, is endemic to the tropical rainforest of northeastern Queensland, Australia. A single lead-like enhanced fraction of A. scandens showed potent inhibition against human prostate cancer PC3 cells. Chemical investigation of this plant resulted in the isolation of two new aryltetralin lignans, austrobailignans 8 and 9 (1 and 2), and the synthetic compound nicotlactone B (3), newly identified as a natural product together with nine known lignans (4-12). Their structures were established on the basis of spectroscopic analyses. Absolute configurations of the new compounds were determined by quantum chemical electronic circular dichroism (ECD) calculations employing time-dependent density functional theory. The ECD calculations were also used to assign the absolute configuration of marphenol K (4) and revise the absolute configuration of kadsurindutin C (20). Ten out of the 12 isolated compounds inhibited the growth of PC3 cells with IC50 values ranging from micromolar to nanomolar. Marphenol A (5) was found for the first time to induce apoptosis and arrest the S cell cycle phase of PC3 cells.

The leaf oils of four species of Cryptocarya, endemic to Australia, were examined. These species are known colloquially as 'coconut laurels' due to the purported distinctive aroma from the crushed foliage. C. cocosoides produced an oil in which bicyclogermacrene (3-26%), spathulenol (16-47%), massoia lactone (6-pentyl-5,6-dihydro-2H-pyran-2-one) (11-15%), (6-heptyl-5,6-dihydro-2H-pyran-2-one (0.3-3%) and benzyl benzoate (0.2-5%) were the principal components. C. cunninghamii showed a second chemotype to that previously published, with benzyl benzoate (80.2%) being the principal component. C. bellendenkerana gave a leaf oil in which the major components were the terpenes limonene (8.3%), β-phellandrene (11.8%) and viridiflorene (9.1%). The principal components of the leaf oil of C. lividula were bicyclogermacrene (26.1%), spathulenol (21.1%) and β-eudesmol (6.1%). Benzaldehyde and acetophenone were both present in amounts of less than 0.7%. Only C. cocosoides and C. cunninghamii have been found to have a 'coconut' aroma mainly due to the presence of massoia lactone and homologues.

Changes in the potential habitat of five allopatric species of threatened Macrozamia cycads under scenarios of increased ambient temperature were examined. A lack of seed dispersal, poor recruitment, low seedling survival, obligate pollinator mutualisms and continued habitat loss have led to extant populations being largely restricted to refugia. Models predict that the area of suitable habitat will further contract and move upslope, resulting in a reduced incidence within protected areas with increasing annual mean temperature. Areas of potential habitat for all five species are also predicted to become increasingly isolated from one another, further reducing the exchange between metapopulations and subpopulations, exacerbating existing threatening processes.

Aim The geology and hydrology of the Central Ranges of Australia provide refuge for more mesic-adapted taxa unable to survive in the surrounding deserts. Whether this area has been a long-term refuge for mesic-adapted taxa is uncertain. Mesic-adapted taxa in the region have been argued as relicts', remnants of wet forests once covering the region. This scenario hypothesizes that relicts' survived in pockets of moist habitat in the Central Ranges as the Australian arid zone expanded. Here, we test an hypothesis of long-term occupancy in the Central Ranges for a cycad, Macrozamia macdonnellii, a taxon of conservation concern and also one frequently described as an ancient relict'. Location Australia. Methods A haplotype network, derived from DNA sequences of two chloroplast regions, was used to infer the biogeographical history of Macrozamia across Australia. Specifically, the question of long-term occupancy of the Central Australian Ranges is addressed. Results Macrozamia macdonnellii shares a haplotype with five eastern species. However, unique haplotypes restricted to only a part of the MacDonnell Ranges Interim Biogeographic Regionalisation of Australia region are also present. Western Australian species of Macrozamia form a lineage distinct from those in the rest of Australia. Main conclusions The shared haplotype, nested within haplotypes from eastern Australia, indicates that M.macdonnellii is relatively recently derived from ancestral lineages of eastern Australia. This starkly contrasts with species of Macrozamia in Western Australia, which show long-term isolation from those in the east. Unique haplotypes in populations of M.macdonnellii indicate that the species has occupied the region for sufficient time to accumulate variation. Furthermore, this variation appears to be geographically structured. If so, it indicates that M.macdonnellii is undergoing population differentiation, and possible speciation, in different regions of the MacDonnell Ranges. Isolated populations with unique haplotypes might be evolutionarily significant units that should be conserved.

An antitropical distribution represents an intriguing disjunction, in which a given species or sister lineages occupy regions north and south of the tropics but are absent from the intervening areas. Solenogyne mikadoi endemic to the Ryukyu Archipelago is regarded as an Australian element. Testing the phylogenetic relationship with Australian congeners and discussing the onset timing and causes of the disjunction would potentially enhance the understanding of antitropical distribution. A nuclear ribosomal DNA phylogeny was reconstructed using Bayesian and most parsimonious criteria with allied genera. Solenogyne was monophyletic and clustered with Lagenophora huegelii endemic to Australia, indicating the antitropical distribution and Australian origin of Solenogyne. Multispecies coalescent analysis based on nuclear ribosomal DNA and chloroplast DNA indicated the divergence of S. mikadoi and Australian congeners in the Plio-Pleistocene. Phylogenetic network analyses suggested that the ancestral lineage of S. mikadoi first colonized the southernmost island in the archipelago and then dispersed northward. The migration to the archipelago likely followed the flourishing of Solenogyne in open vegetation communities that radiated in south-eastern Australia during the late Pliocene. This disjunction might arise through long-distance dispersal across the tropics or, alternatively, through extinction in the tropics as a result of unsuitably high temperatures during climate oscillation and/or competitions from diverse tropical flora surviving since the early Tertiary.

Seven new and three known bisresorcinols, grevirobstol A (=5,5′-((6Z,9Z)-hexadeca-6,9-diene-1,16-diyl)bisresorcinol; 8), 5,5′-[(8Z)-hexadec-8-ene-1,16-diyl]bisresorcinol (9), and 2-methyl-5,5′-[8Z)-hexadec-8-ene-1,16-diyl]bisresorcinol (10) were isolated from the stems of Grevillea glauca. The new compounds were identified on the basis of spectroscopic data as (Z)-6,7-didehydroglaucone A (1), glaucones A and B (2 and 3, resp.), 2-(3-hydroxyisopentyl)bisnorstriatol (4), 2-(3-methylbut-2-en-1-yl)bisnorstriatol (5), 2′-methylgrebustol A (6), and glaucane (7).

A detailed investigation of the wood, leaf, branch and root oil of Eremophila mitchellii (Benth.) was carried out by a combination of GC-FID, GC-MS and NMR. The wood oil was composed predominantly of eremophilanes, a rare class of biologically active, bicyclic sesquiterpenoids. The root oil was also found to contain the eremophilanes together with the zizaene sesquiterpene, sesquithuriferone. 9-Hydroxy-1,7(11),9-eremophilatrien-8-one and the known 1(10),11-eremophiladien-9-one (eremophilone), 9-hydroxy-7(11),9-eremophiladien-8-one (2-hydroxyeremophilone), 8-hydroxy-11-eremophilen-9-one (santalcamphor), 8-hydroxy-10,11-eremophiladien-9-one, sesquithuriferone and 8-hydroxy-1,11-eremophiladien-9-one were purified and elucidated by NMR. Three approaches to the purification of the major eremophilanes from the wood oil are described. (+) Spathulenol, α-pinene, globulol, viridiflorene were the major constituents of the leaf oil. All of the essential oils and the eremophilanes exhibited cytotoxicity against P388D(1) mouse lymphoblast cells in-vitro.

Two new (1 and 2) and six known hasubanan alkaloids (3-8) and one morphinane alkaloid (9) were isolated from the leaves of the North Queensland rainforest vine Stephania japonica. The structures of 1 and 2 were determined by interpretation of their 1D and 2D NMR spectra. The hasubanan alkaloids showed affinity for the human delta-opioid receptor with IC(50) values ranging from 0.7 to 46 microM. The compounds were also tested for their affinity to micro- and kappa-opioid receptors and shown to be inactive against kappa-opioid receptors, but were of similar potency against the micro-opioid receptor.

The Malesian species of the predominantly New Caledonian genus Austrobuxus were revised. Three species are recognized. Austrobuxus nitidus is widespread from south Thailand to Borneo. Characteristic for this species are the very short papillae of the caruncle. The caruncle papillae are much longer in the other two, newly described species. Austrobuxus celebicus sp. nov. is endemic to Sulawesi, where it is found on ultramafic soils, and A. dentatus sp. nov. is an endemic species of western New Guinea. The former is notable for the very small fruits and the latter for the teeth-like glands along the leaf blade margins, unique within the genus.

The essential oils of three Australian species of the genus Cassytha have been investigated using GC and GC/MS. Cassytha filiformis produced an oil that was sesquiterpenoid in nature, with bicyclogermacrene (12–26%), spathulenol (27–36%) and β-caryophyllene (5–10%) being the principal components. Cassytha pubescens appeared to exist in several chemical types. A Principal Components Analysis of the oils appeared to indicate that there were three chemical types present in the 13 collections. The first variety contained (E)-nerolidol (26.7%) and β-caryophyllene (23.5%) as major components. The second chemical variety of this species showed elevated levels of α-copaene (4–6%), moderate amounts of β-caryophyllene (8–14%), caryophyllene oxide (3–17%) and bicyclogermacrene (2–9%), and high levels of spathulenol (27–32%). The third variety was more variable and contained significant amounts of spathulenol (4–21%), bicyclogermacrene (2–40%), β-caryophyllene (1–31%), and aromadendrene (0.7–10%). The princi...

The leaf oils of the 19 Australian species of Endressia, Steganthera and Wilkiea within the family Monimiaceae have been examined by GC and GC/MS. All produced oils in poor yields that were dominated by sesquiterpenes. Endressia wardellii gave a leaf oil in which α-humulene (14–17%) and bicyclogermacrene (17–24%) were the main components. The leaf oil of Steganthera australiana was almost entirely sesquiterpenoid with no one single compound predominating. Steganthera cooperorum, from two disjunct population centers produced different oils indicating significant chemical divergence. In plants from Topaz and Wooroonooran National Park the major components identified were aromadendrene (6–10%), viridiflorene (7–8%), globulol (7–9%) and b-eudesmol (8–11%); dodecanal (2–4%) was also present. However, material from North Mary Logging Area and Daintree National Park produced an oil dominated by elemol (30–42%) and hedycaryol (approx. 8%). These compounds were accompanied by α-, β- and γ-eudesmol (10–14%...

Seven new bisresorcinol derivatives, together with four known resorcinols, have been isolated from the ethyl acetate extract of the stems of Grevillea floribunda. Five of the new compounds (floribol A–E) were characterized as bisnorstriatol derivatives substituted at C-2 of both resorcinol units with variously modified prenyl (3-methylbut-2-enyl) units. The remaining two new compounds are similarly substituted derivatived of grebustol-B.

Romnalda ophiopogonoides Conran, P.I.Forst. et Donnon sp. nov. from the Cape Tribulation -Daintree area in the Wet Tropics bioregion of north-east Queensland is described, illustrated and compared with related species. A conservation status of Endangered is proposed. Notes on habitat, distribution and cytology and a key to the species of Romnalda are provided.

High-throughput screening of a plant and marine invertebrate extract library to find natural products with rat thyrotropin-releasing hormone (TRH) receptor-2 binding affinity led to the isolation of four new, myrtucommulones F-I (3-6), and two known, myrtucommulones A (1) and D (2), active acylphloroglucinols from the seeds of the Queensland tree Corymbia scabrida. Their structures were assigned from interpretation of 2D NMR and high-resolution ESIMS data. The relative configuration of the stereogenic centers for all six compounds was deduced from ROESY correlations. This is the first time that myrtucommulone A (1) has been isolated as a single pure compound. The structure of myrtucommulone D (2) has been revised. Myrtucommulones A, D, and F-I showed rat TRH receptor-2 binding affinity with IC50 values of 39, 11, 16, 24, 31, and 16 microM, respectively.

Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS or ESI-FTMS) was used to screen 192 natural product extracts and a 659-member natural product-based fragment library for bindings to a potential malaria drug target, Plasmodium falciparum Rab11a (PfRab11a, PF13_0119). One natural product extract and 11 fragments showed binding activity. A new natural product, arborside E, was identified from the active extract of Psydrax montigena as a weak binder. Its binding activity and inhibitory activity against PfRab11a were confirmed by ESI-FTMS titration experiments and an orthogonal enzyme assay.

Eight phenolic compounds, including two mixtures of two compounds, were isolated from the ethyl acetate extract of leaves and stems of Homalium brachybotrys. They were identified on the basis of spectroscopic data as quercetin-3-O-beta-glucopyranoside, luteolin-7-O-beta-glucopyranoside, 5,6-dihydro-6-beta-glucopyranosyloxy-3-(hydroxyphenyl-methyl)-2(4H)-benzofuranone (cochinolide 6-O-beta-glucopyranoside) (1), 2-(6-benzoyl-beta-glucopyranosyloxy)-5-hydroxybenzyl alcohol (poliothrysoside) (2), 2-(beta-glucopyranosyloxy)-5-hydroxybenzyl alcohol (salirepin) (3), 4,5-dihydro-7a-beta-glucopyranosyloxy-3-(hydroxyphenylmethyl)-2(7aH)-benzofuranone (isocochinolide-7a-O-beta-glucopyranoside) (4), 5,6-dihydro-3-(hydroxyphenylmethyl)-2(4H)-benzofuranone (6-deoxycochinolide) (5) and 3-benzylidine-6-hydroxy-2-benzofuranone (1'deoxy-4,5,6-dehydrocochinolide) (6). Benzofuranones (4), (5) and (6) are new natural products. The compounds isolated support the argument that Homalium is best placed in the Salicaceae s.l.

The leaf oils of the species of Philotheca growing in Queensland and northern New South Wales have been examined by combined GC and GC/MS. Philotheca cuticularis, both subspecies of P. difformis, P. glasshousiensis, P. myoporoides subsp. myoporoides, P. epilosa, P. obovata, P. queenslandica and P. sporadica all produced leaf oils in which the major component (

The leaf oils for species in the genus Bosistoa have been examined by GC and GC/MS. Bosistoa brassii produced a sesquiterpenoid leaf oil, the principal components of which were β–caryophyllene (2–12%), α-humulene (1–18%,) and bicyclogermacrene (trace—24%). Bosistoa floydii produced a leaf oil (in poor yield) dominated by α-pinene (46–67%). The leaf oil of B. medicinalis contained significant amounts of α–pinene (13–57%). The principal sesquiterpene present in the oil was β–caryophyllene (1–9%). Bosistoa pentacocca, in both varieties, produced a leaf oil devoid of monoterpenes. The principal components in the leaf oil of this species were δ–cadinene (6–11%), α–copaene (2–7%), germacrene D (4–14%) and α–cadinol (2–8%). The leaf oils from B. transversa were variable, but the majority contained significant amounts of monoterpenes, with α–pinene (24–83%) being the principal component. The oil yields in all cases were poor (0.02–0.3%). Recommendations for taxon recognition in Bosistoa are made.

The leaf oils of the 18 species and four subspecies of the genus Callitris endemic to Australia have been investigated by a combination of GC and GC/MS. All taxa produced oils in poor to moderate yields. Callitris baileyi produced a leaf oil in which α-pinene and limonene together, contributed the majority of the oil, while in Callitris canescens methyl citronellate also made significant contributions to the oil. In C. columellaris, limonene was the principal component, contributing up to 78% of the oil. Callitris drummondii gave a leaf oil which showed two chemical varieties. The samples from Western Australia contained large amounts of α-pinene (67–69%), while the sample from South Australia contained limonene (10.9%), bornyl acetate (24.2%) and geranyl acetate (14.9%) as significant components. In C. endlicheri the main components were limonene, α-pinene and bornyl acetate. Limonene and α-pinene were the principal components of the leaf oil of C. glaucophylla. Callitris gracilis ssp. gracilis ...

Five new indolizidine alkaloids, grandisines C, D, E, F, and G (4-8), and one known indolizidine alkaloid, (-)-isoelaeocarpiline (3), were isolated from the leaves of Elaeocarpus grandis and their structures determined by 1D and 2D NMR spectroscopy. Grandisine C (4) is isomeric with the known compound rudrakine (1). The absolute configuration of grandisine D (5) was deduced by its conversion to (-)-isoelaeocarpiline. Grandisine E (6) contains a novel tetracyclic ring system. Grandisine F (7) is the 14-amino analogue of grandisine C. Grandisine G (8) contains the novel combination of a piperidine attached to an indolizidine. Grandisines C, D, F, and G and (-)-isoelaeocarpiline showed receptor binding affinity for the human delta-opioid receptor with IC(50) values of 14.6, 1.65, 1.55, 75.4, and 9.9 microM, respectively.