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All four of the myodesmoid β-ketols (la) formally derivable from (-)-(S)-myoporone (3a),three of the four myomontanoid β-ketols (2a) from ent-(3a) and two of the four 10,ll-dehydro myodesmoid β-ketols (lb) from (3b), have been found in Myoporaceous plants and characterized by g.1.c. retentions and by Kovats indices and mass spectra of their trimethylsilyl ethers. Five of these ketols have been obtained as crystalline solids whose stereochemistry has been determined in part. All are readily converted into myoporone or 10,11-dehydromyoporone by pyrolysis during distillation or gas chromatography, and by base or alumina. These facile ring-opening reactions have previously concealed the widespread occurrence of these furanosesquiterpene β-ketols in the Myoporaceae. In the few specimens of Myoporum betcheanum, M. deserti and M. montanumwhich have been suitably examined, the β-ketols form a complex mixture of from four to eight ketols differing in carbon skeleton, unsaturation and/or stereochemistry. P-Ketols have been recognized in eight species of Myoporum and three of Eremophila. Both enantiomers of one myodesmoid ketol have been isolated. A mixture of ketols showed a toxicity similar to that of (-)-ngaione. A quick and quantitative micro method for the preparation of g.l.c.-injectable carbon disulfide solutions of volatile leaf constituents is described.

Four furanosesquiterpene β-hydroxy ketones previously isolated from Myoporumspp., and given tentative names, are now assigned complete stereostructures from n.m.r. and X-ray data. The compounds are (5R,7R,9S)-9-hydroxy-5,9-dihydromyomontanone (Woogaroo) (1a), (5S,7R,9R)-9-hydroxy-5,9-dihydro- myomontanone (Redbank) (1b), (5R,7R,9R)-9-hydroxy-5,9-dihydromyomontanone (Perillup) (1c) and (4S,7S,8R)-4-hydroxy-10,11-didehydro-4,8-dihydromyodesmone (Carney's ketol) (2a). The stereo- structures of two other previously reported compounds, Kindon ketol ((4S,7S,8R)-4-hydroxy-4,8- dihydromyodesmone) (2b), and Carr's ketol ((4S,7S,8S)-4-hydroxy-4,8-dihydromyodesmone) (2c), follow from the above results.

The first example of a new class of tricyclic diterpenes together with two new viscidanes have been isolated from a variety ofEremophila georgei. The structures of the viscidane compounds were assigned on the basis of spectroscopic data and comparison with model compounds. The structure and relative stereochemistry of the lactone (2), which represents a new diterpene skeleton, were established by spectroscopic and X-ray crystallographic methods. The derivation of (2) from a viscidane is suggested.

A common variety of Myoporum deserti A. Cunn. (Ellangowan Poison Bush) yields an essential oil consisting largely of the iridoid monoterpene, (1R)-1-methoxymyodesert-3-ene, C11H18O2,(1R,4aS,7R,7aR)-1-methoxy-4,7- dimethyl-1,4a,5,6,7,7a-hexahydrocycopenta[c]pyran, b.p. 67°/2 mm,[α]D- 165°. This cyclic acetal is hydrolysed to methanol and a mixture of two epimeric cyclopentanoid dialdehydes which are oxidized to the two epimeric trans,trans-nepetalinic acids and yield (+)-(R)-actinidine with Brady's reagent. (1R)-1-Methoxymyodesert-3-ene is oxidized by ozone/hydrogen peroxide to (1R,2R,5R)-2-acetyl-5- methylcyclopentanecarboxylic acid. Hydrogenation yields mainly (1R)- methoxymyodesertan, hydrolysed by aqueous maleic acid at room temperature to methanol and a cyclic hemiacetal, (1R,4R,4aR,7R,7aR)- 4,7-dimethyl-1,3,4,4a,5,6,7,7a-octahydrocyclopenta[c]pyran-1-ol. Oxidation of this cis,cis-hemiacetal by bromine in acetate buffer yields a lactone further oxidized by chromic acid to (2R,1'S,2'R,3'R)- 2-(2'-carboxy-3'-methylcyclopentyl)-propionic acid. (1R)-1-Methoxymyodesertan, refluxed with aqueous phthalic acid, yields (+)-(4R,4aR,7R)-4,7-dimethyl-3,4,4a,5,6,7-hexahydrocyclopenta[c]pyran. Treatment of the hexahydropenta[c]pyran, the cis,cis-hemiacetal or (1R)-1-methoxymyodesertan with hydrochloric acid yields a trans,trans-hemiacetal, (1R,4R,4aR,7R,7aS)-4,7-dimethyl- 1,3,4,4a,5,6,7,7a-octahydrocyclopenta[c]pyran-1-ol, which equilibrates in solution to a mixture of α- and β-anomers. Spectral studies of these and otherproducts establish the configuration of the natural product at C1. (1R)-1-Methoxymyodesert-3-ene is not toxic to sheep as are the β- substituted furans characteristic of most other chemovarieties of M. deserti.

Eremophila fraseri occurs in arid and semiarid areas of inland and northern Western Australia. The spreading bushes, 1 to 2.5 tn high, are covered with a thick, viscid layer of resin. The flavonoid and terpenoid components of the leaf resins were identified by thin-layer chromatography. Five types of resin patterns were recognized, and each was found to have a distinct geographical distribution. Each occurs sympatrically with at least one other resin pattern. It is suggested that hybridization between two tetraploid races is occurring, and that the progeny can be recognized by their resin com- position.

Summary Glandular hairs ofEremophila fraseri secrete a resin containing terpenoid and flavonoid components. Each glandular hair secretes about 0.2 µg resin, which constitutes 17% of the mature leaf dry weight. The glandular heads are characterized by proliferated endoplasmic reticulum associated with numerous amoeboid plastids having reduced internal lamellae. Nuclear crystals occur in the stalk and head cells of the glands. The head cells also contain calcium oxalate crystals. Resin release occurs through an apical secretion cavity. Cutinization of the walls of the head and supporting cells, and the role of specialized structures of the head cells in resin formation are discussed.

A further chemovariety of Myoporum deserti A. Cunn . yields an essential oil consisting predominantly of the iridoid hemiacetal esters, (+)-(1R)-and(-)-(1S)-1-acetoxymyodesert-3-ene. Hydrolysis of either ester yields (1S,2R,5R,1′ξ)-2-(1′-formylethyl)-5-methylcyclopentane-1-carbaldehyde and acetic acid or, in the presence of Brady's reagent, the bis-2,4-dinitrophenylhydrazone of the 1R-epimer. The stereochemistry at C1 of the esters follows from the close correlations in 1H and 13C n.m.r . spectra and o.r.d . curves of the (-)-ester and the ether (-)-(1R)-1-methoxymyodesert-3-ene. Hydrogenation of the esters in methanol yields mainly myodesertan , (4S)- myodesertan , (1R)-1- methoxymyodesertan and (1R, 4S)-1-methoxymyodesertan and usually no acetates. Acetolysis of (1R)-1-methoxymyodesertan even under mild conditions yields (1R, 7aS)- and (1S, 7aS)-1-acetoxymyodesertan with trans rather than cis ring junctions.

Pulvinaria dodonaeaeare recorded as feeding on EremophilaR. Br. (Myoporaceae) within the arid shrublands of Western Australia. Ten percent of the E. margarethaepopulation (i.e. 90 plants/ha) were killed by this scale. E. fraserisubsp. galeataappears hardier with minimal affects on plant vitality.

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The absolute configuration of the acids (I)‐(III) is deduced from an X‐ray analysis of a derivative of (I).

Ethanolic extracts of five traditional Australian medicinal plants, previously shown to display antibacterial activity against laboratory strains of the Gram positive bacteria Staphylococcus aureus and Enterococcus faecalis, were investigated for their abilities to inhibit clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Using plate-hole diffusion assays, the following results were obtained: (a) extract from the leaves of Eremophila alternifolia (Myoporaceae) showed activity against MRSA; (b) extract from the leaves of Acacia kempeana (Mimosaceae) showed incomplete inhibition of VRE; (c) extracts from the leaves of Amyema quandong (Loranthaceae) and Eremophila duttonii (Myoporaceae) were active against both types of bacteria; (d) extract from the stem base of Lepidosperma viscidum (Cyperaceae) was active against MRSA and exhibited incomplete inhibition of VRE. All active extracts were evaluated using time-kill assays. Most of the extracts showed bactericidal effects and reduced the number of viable cells by 4–6 logs within four hours, while the extracts from Acacia kempeana leaves and Lepidosperma viscidum stem base exhibited bacteriostatic activity against VRE. The extract from the leaves of Eremophila duttonii was the most active and reduced the number of viable cells of MRSA and VRE to undetectable levels within 1 hour.

AbstractMyoporumis an Australian genus of family Myoporaceae widely cultivated in Libya as an ornamental plant. The hydrodistilled essential oil of fresh Libyan Myoporum acuminatumR. Br fruits (1.2%) was analyzed by GC-MS. Twenty nine constituents were identified. The oil was characterized by high content of oxygenated compounds (60.83%) mainly sesquiterpenes. The major monoterpenoids were D-limonene (34.10%) and (-) carvone (11.76%) while negaione (20.5%) and myomontanone (8.5%) were major furanoid sesquiterpenes. The antimicrobial screening showed that essential oil of this plant has promising antimicrobial activity against a number of tested microorganisms: Gram positive bacteria: Streptococcus pneumonia, Bacillis subtilis, Gram negative bacteria as Escherichia coliand certain fungi named Geotricum candidum, Aspergillus fumigates,Syncephalastrum racemosum

Recent molecular phylogenetic studies in Lamiales have shown that the large group traditionally recognised as Scrophulariaceae is not monophyletic. Efforts to reconstruct the phylogeny of this large clade and to revise its classification to reflect that phylogeny have resulted in seven monophyletic groups, comprised mostly of members of Scrophulariaceae s.l., recognised as families in recent angiosperm classifications. These are Scrophulariaceae s.s., Orobanchaceae, Veronicaceae (cf. Plantaginaceae), Phrymaceae, Calceolariaceae, Linderniaceae, and Stilbaceae. Sampling completeness at the genus level varies from group to group, but is quite good for many. A few individual genera formerly assigned to Scrophulariaceae do not fit into any existing clade recognised at family rank and are left, at present, unassigned to family. In addition to the recognition of several clades comprised primarily of former members of Scrophulariaceae s.l., several groups previously recognised as families are now included within some of these clades. For example, Scrophulariaceae s.s. includes Buddlejaceae and Myoporaceae, and Veronicaceae includes Callitrichaceae, Globulariaceae, Hippuridaceae, and Plantaginaceae. The clades now recognised as families often are not easily diagnosed, but in many cases are more consistent with certain functional traits and geographical patterns. Examples include Orobanchaceae, which comprises all of the parasitic plants (hemiparasites and holoparasites) and Scrophulariaceae s.s., which is predominantly a southern hemisphere group.

Four iridoid glycosides isolated from different species of Eremophila(Myoporaceae) were tested for their effects on the Langendorff rat heart. Melampyroside (1), verminoside (2), ferruloylajugol (3) and catalpol (4) all significantly decreased contractile force in the isolated rat heart test. Within a minute after administration all, except catalpol, significantly increased heart rate and coronary perfusion rate. These results are compared to those of other cardioactive iridoid glycosides described in the literature.

In 83 species of the familiesMonotropaceae, Apocynaceae, Oleaceae, Scrophulariaceae, Lentibulariaceae, Bignoniaceae, Martyniaceae, Myoporaceae, Verbenaceae, Lamiaceae, Campanulaceae, andLiliaceae, protein bodies in the cell nuclei have been found, in 68 of these species for the first time. On the basis of their structure in accordance with morphological characters the generaBurgsdorfia, Hesiodia, Olisia, andPhlomoides of theLamiaceae are accepted;Lamium is divided intoLamium, Lamiastrum andOrvala; two new combinations are established:Kickxia campyloceras (Rech. fil. &Esfandiari)Speta andEtornotus papilionaceus (Burm. in L.)Speta. Deviating shape or lack of protein bodies corroborate former taxonomic decisions, e.g. the transfer ofMonotropa toMonotropaceae or the separation ofGaleopsis andLadanum; Veronica schmidtiana should not be included inPseudolysimachion. Systematic affinities are discussed primarily withinScrophulariaceae because nuclear protein bodies have been studied already in many species of this family. ForCampanula patula two 2 x populations are reported.

Summary: Aeration of tissue cultured rare Australian plantsConostylis wonganensis S.D. Hopper (Haemodoraceae);Diplolaena andrewsii Ostenf.;Drummondita ericoides Harvey (Rutaceae);Eremophila resinosa F. Muell. (Myoporaceae);Eucalyptus ‘graniticola’ (Myrtaceae);Lechenaultia pulvinaris C. Gardner (goodeniaceae); andSowerbaea multicaulis E. Pritzel (Liliaceae) has been found to reduce vitrification in sensitive species as well as significantly improving shoot quality and transfer to soil in most study species. A simple 7-mm hole with a double-layer insert of filter paper in the polypropylene screw lids of the culture vessel decreased shoot vitrification over a 4-wk culture period. The method has implications for facilitating the tissue culture of other rare Australian plants and reducing the occurrence of this developmental abnormality.

Activity directed isolation studies of the ethanol extract of Bontia daphnoides L (Myoporaceae) leaves and stems led to the isolation of epingaione, a sesquiterpene furan. This compound was previously described by Chinnock et al. (1987) from the same plant. The compound showed growth regulatory activities on gravid adult female Boophilus microplus Canestrini (the southern cattle tick). The dose required for inhibiting the hatching of B. microplus eggs by 50% (Fid50)was 0.4±0.06 mg/g of the tick body weight. The Fid50 dose inhibited the sequestration of protein into eggs oviposited by 80%. These eggs were non-agglutinated and wrinkled. Histological examination of ovarian sections from the treated ticks revealed significant degeneration of funicle cells and reduction in yolk content.

Monistria discrepans(Walker) in south‐west Queensland is an obligate univoltine species. A temperature controlled diapause of the eggs confines hatching of eggs laid in the March‐May period to early October. Nymphs develop throughout the summer resulting in a population entirely of adults by April. The presence of nymphs coincides with the greatest growth of the host plant Eremophila gilesiiF. Muell. In the Charleville area of south‐west Queensland, feeding is restricted to Eremophilaand Myoporum(both Myoporaceae) but species of other families of plants are utilized in eastern areas of Queensland. In laboratory tests, nymphs failed to develop on species of Gramineae, Compositae and Leguminosae. Parasitism by the mites Leptussp. and Podapolipussp. nr. lahilleiNaudo reached levels of 7.0% and 94.4% respectively during 1973–75. The non‐specific tachinid Ceracia fergusoni(Malloch) and sarcophagid Blaesoxipha pachytyli(Skuse) parasitised mainly adult females (up to 20.8% total parasitism) but also attacked final instar female nymphs and adult males. The hyperparasite Perilampussp. nr. cairnsensisGirault was found in C. fergusonilarvae. The fungus, Aspergillus flavusLink, infected up to 40.9% of field‐collected adults but survival of infected individuals was high except after rain or in the high humidity of the laboratory. Although insectivorous birds are present in the area they exerted little control over the M. discrepanspopulation.

Two new (1and 2) and one known (3) sesquiterpene bis-butenolides have been isolated from the aerial parts of Eremophila homoplastica (Myoporaceae). The structures of the new compounds were determined by spectroscopic studies and confirmed by single-crystal X-ray crystallography of one (2) of the new compounds. Spectroscopic evidence for the structure of a new related sesquiterpene butenolide (4) from E. forrestii is presented. The isolation of the phenylethanoid glycosides, verbascoside and poliumoside, from E. forrestii is noted.

Teleonemia scrupulosa (Stål) (Hemiptera, Tingidae) is a native of the tropical regions of the Americas and has been extensively used as an agent for the biological control of the noxious weed Lantana camara Linn. (Verbenaceae). It was introduced first into Hawaii1; since then it has been introduced into Fiji2, Australia3, Indonesia4and other island groups in the Pacific. It is also established in India5, Mauritius, and South6, Central7and East Africa. In general the level of control achieved in these areas has been disappointing, although severe local defoliation and partial control has been reported from many of these countries, and it is generally considered to be a useful addition to the insect complex used in the control of Lantana. Exhaustive tests in Fiji and Australia showed that this Tingid would feed on none of the plants tested except Lantana8. The bug was reported in Texas on Callirhoe involucrata (Malvaceae) and a plant of the mint family but was unable to breed or live long on them9. Its release in India was not recommended because laboratory tests showed that it could feed on teak (Tectonagrandis Linn.) which is also a member of the Verbenaceae although breeding was slow and Lantana was preferred10. When it escaped at Dehra Dun, however, it became established on Lantana but could not be found on nearby teak5. The only other previous records of attack by T. scrupulosa on other plants are its occurrence on Myoporum sandwicensis (Myoporaceae) and species of Xanthium (Compositae) in Hawaii, ebony in the United States, and Lippia alba (Verbenaceae) in the Antilles, according to the catalogue just published, which includes some hitherto overlooked records11.