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1.
Two new sesquiterpene lactones with an ,β-unsaturated aldehyde group have been isolated from the roots of Saussurea lappa. Their stereostructures have been established by the combined use of spectroscopic as well as chemical methods via their synthesis from dehydrocostus lactone. 相似文献
2.
The components of the two major classes of natural products of the composite Encelia farinosa, sesquiterpene lactones and benzopyrans/benzofurans (chromenes), were resolved and quantified by high performance liquid chromatography. Geographic variation was examined over a range of mesic and xeric populations from California and Arizona (USA). The concentration of farinosin, a sesquiterpene lactone, varies significantly between individuals and seasonally within individuals. Ontogenetic comparisons revealed interpopulation variations within sesquiterpene lactones and chromenes. A geographic survey suggests the presence of two putative chemical races which vary in the amounts of sesquiterpene lactones and chromenes present. The adaptive significance of this quantitative variation is discussed. 相似文献
3.
A total of 43 HPLC peaks tentatively considered to be sesquiterpene lactones was detected from a survey of the 18 taxa (eleven species and seven subspecies) of Helianthus sect. Helianthus using a recently developed microtechnique. All but one of the taxa showed characteristic sesquiterpene lactone patterns with between six and 15 compounds each. H. paradoxus appears to be the only species in the genus in which these compounds are not detectable. Comparison with available reference compounds allowed assignment of structures to 21 of the compounds. Known compounds can be classified into five major structural subtypes, the systematic distribution of which divides the section into three well-defined subgroups. The sesquiterpene lactone profiles of the other two annual species of the genus, H. agrestis and H. porteri, exhibit significant differences relative to any species of sect. Helianthus, which supports their exclusion from the section. 相似文献
4.
The crude syrups of Melampodium americanum L. and Melampodium leucanthum Torr. and Gray and their principal sesquiterpene lactones, melampodin A and melampodinin A, significantly inhibit growth and deter feeding of the fall armyworm, Spodoptera frugiperda (J. E. Smith). Melampodin A and melampodinin A caused 2.3 × and 5.5 × greater S. frugiperda larval mortality, respectively, than glaucolide A, a sesquiterpene lactone with previously demonstrated insect allelochemic effects. 相似文献
5.
Samah Djeddi Catherine Argyropoulou Helen Skaltsa 《Biochemical Systematics and Ecology》2008,36(5-6):336-339
The aerial parts of Centaurea grisebachii ssp. grisebachii, a Greek endemic species belonging to section Acrolophus (Cass.) DC., were investigated for the occurrence of sesquiterpene lactones. The eudesmanolide, 4-epi-malacitenolide was the major compound. In addition to the sesquiterpene lactones, five flavonoid aglycons, two lignans, one nor-isoprenoid and one sterol were found. 相似文献
6.
The investigation of two East African and a Madagascarian Vernonia species afforded several new sesquiterpene lactones. Vernonia colorata subsp. grandis gave 19-hydroxyglaucolide A and three vernodalin derivatives, V. holstii five new cistifoliolides and V. zanzibarensis five lactones closely related to brachycalyxolide. The structures were elucidated by high field NMR techniques. The chemotaxonomic relevance is discussed briefly. 相似文献
7.
Otmar Spring 《Biochemical Systematics and Ecology》1989,17(7-8):509-517
The localization of sesquiterpene lactones in glandular trichomes of numerous Asteraceae makes it possible to use a microtechnique to investigate their occurrence. General aspects of the utility and value of the method in comparison with standard procedures are discussed with special focus on the advantage of a quick, inexpensive and reproducible analytical technique in systematic and biochemical studies. Using analytical HPLC, it was possible to establish the sesquiterpene lactone profiles of all 64 known taxa of the genus Helianthus. Intraspecific variation of sesquiterpene lactones was found to be low in comparison to morphological characters. Hybrids were shown to possess the additive sesquiterpene lactone patterns of their parents. This suggests that the chemistry of these compounds could be a useful tool in taxonomy. 相似文献
8.
From aerial parts of Rhaponticum pulchrum the guaiane-type sesquiterpene lactones aguerin B, janerin, 19-deoxyjanerin, chlorojanerin, 15-dechloro-15-hydroxychlorojanerin, cynaropicrin, cebellin G, repdiolide and repensolide were isolated, together with the phenylpropanoid glucoside syringin. In no-choice and two-choice feeding experiments aguerin B, chlorojanerin and syringin were shown to be good antifeedants against the three species of the stored product insect pests Sitophilus granarius, Trogoderma granarium and Tribolium confusum, while janerin and cynaropicrin inhibited feeding of the latter species. However, the highest antifeedant activity was recorded for the extract of the plant enriched in sesquiterpene lactones. The unexpected finding was that syringin inhibited feeding of the insects. 相似文献
9.
Samples of 31 populations of Parthenium hyserophorus from varius areas of its world distribution were examined for their sesquiterpene lactone composition. On the basis of the occurrence of sesquiterpene lactones the samples were divided into seven chemical types. The most common is a type represented by plants containing parthenin as a major sesquiterpene lactone, and coronopilin and tetraneurin-A. All samples from North and Central America, Venezuela, South Africa, India, Australia, and one sample from Jamaica belong to this type. This suggests that P. hysterophorus recently introduced to South Africa, India and Australia originates in North and (or) Central America. On the other hand, there is a great diversity among examined South American populations. Plants from these populations usually contain hymenin which is their major sesquiterpene lactone. Some populations may also contain coronopilin, hysterin, and dihydroisoparthenin. A high diversity in the sesquiterpene lactone chemistry and the morphological differences between individual South American populations of this species indicate the possible existence of several taxa. 相似文献
10.
Aerial parts of Achillea millefolium (Mongolian origin yielded besides desacetylmatricarin two sesquiterpene lactones of a new 3-oxa-guaianolide type, 8-acetyl egelolide and 8- angeloyl egelolide. 相似文献
11.
Klaudia Michalska Anna Stojakowska Janusz Malarz Ivana Dolealov Ale Lebeda Wanda Kisiel 《Biochemical Systematics and Ecology》2009,37(3):174-179
A chemosystematic study of eleven species from the genus Lactuca (Asteraceae) was performed, based on the distributional data for eight sesquiterpene lactones as diagnostic characters. The lactones were identified in leaf and root extracts by comparison of their HPLC retention times and on-line UV spectra with those of reference compounds. Our results support the status of the section Lactuca, subsection Lactuca as a recognizable group within the genus, although Lactuca aculeata is a distinct species. Moreover, sesquiterpene lactone patterns of Lactuca perennis, Lactuca tatarica, Lactuca indica and Lactuca capensis are also given. It is worth noting that the sesquiterpene lactones are absent from Lactuca tenerrima. The chemosystematic impact of lactucin-type guaianolides and the germacranolide lactuside A is discussed briefly. 相似文献
12.
Milka Todorova Antoaneta Trendafilova Bozhanka Mikhova Antonina Vitkova Helmut Duddeck 《Biochemical Systematics and Ecology》2007,35(12):852-858
The flower heads of Achillea distans afforded nine new sesquiterpene lactones (one glaucolide, six guaianolides and two dimeric lactones) in addition to 18 known terpenoids. The structures and stereochemistry of the new compounds were elucidated by spectroscopic methods. The stereochemistry of 11,13-dihydroezomontanin was revised. 相似文献
13.
The discovery of a helenanolide sesquiterpene lactone in Hulsea supports placement of the genus in the tribe Heliantheae. 相似文献
14.
Tom J. Mabry Zeinab Abdel-Baset William G. Padolina 《Biochemical Systematics and Ecology》1975,2(3-4):185-192
Systematic and evolutionary interpretations based upon the distributional data for 27 flavonoids from 39 species and 9 sesquiterpene lactones from 38 species are presented for species of Vernonia mostly from the New World. 相似文献
15.
Qi Song Marco L. Gomez-Barrios Elise L. Hopper Martin A. Hjortso Nikolaus H. Fischer 《Phytochemistry》1995,40(6):1659-1665
Biosynthetic studies of the guaianolide-type sesquiterpene lactones 11βH,13-dihydrolactucin-8-O-acetate and 8-desoxylactucin were performed in Agrobacterium rhizogenes—transformed hairy root cultures of blue-flowered lettuce, Lactuca floridana. The 13C NMR spectra of the two guaianolides labelled by incorporation of [1-13C], [2-13C], [1,2-13C2]acetate and [2-13C]mevalolactone showed patterns of enrichment consistent with a previously proposed biogenetic pathway for guaianolide-type sesquiterpene lactones via the acetate-mevalonate-germacradiene route. 相似文献
16.
Yoshinori Asakawa Reiko Matsuda Masao Toyota Shinske Hattori Guy Ourisson 《Phytochemistry》1981,20(9):2187-2194
Twenty-five Frullania species (liverworts) were chemically investigated. Fourteen species produce allergy-inducing sesquiterpene lactones. Eighteen species contain bibenzyls. The sesquiterpene lactones and bibenzyls are obtained as the major components and they are valuable chemosystematic markers of Frullania species. On the basis of their chemical constituents, Frullania species can be divided into five chemotypes: sesquiterpene lactone-bibenzyl type; sesquiterpene lactone type; bibenzyl type; monoterpene type and cyclocolorenone type. 相似文献
17.
The sesquiterpene lactone chemistry, chromosome numbers and morphology of selected Sonoran Desert Ambrosia taxa are reported. The sesquiterpene lactone distribution correlates with morphologically defined species groups. 相似文献
18.
William C. Burnett Samuel B. Jones Tom J. Mabry William G. Padolina 《Biochemical Systematics and Ecology》1974,2(1):25-29
Larval feeding tests were run to determine the preference of six species of Lepidoptera for two species of Vernonia which produce sesquiterpene lactones and one which has lost the ability to produce these bitter principles. Significant differences between the feeding preferences of the insect species were observed. Further feeding tests were run with a Vernonia leaf powder medium to determine how interspecific chemical differences influenced these preferences. The sesquiterpene lactone, glaucolide-A, was found to reduce larval feeding when incorporated in a Vernonia powder-agar medium. The amount of insect feeding was inversely proportional to the concentration of glaucolide-A in the medium. 相似文献
19.
From several South African Vernonia species, a considerable number of sesquiterpene lactones has been isolated. Together with known compounds, seven members of a new type with an enol lactone ring have been found, their structures being elucidated by spectroscopic methods and some chemical transformations. Furthermore two new derivatives of costunolide are present in two species, and three new guaianolides have been found. From some species, however, no lactones could be isolated. Together with a new bisabolene derivative, a known eremophilone has been isolated, probably for the first time, from a member of the tribe Vernonieae. 相似文献
20.
Sesquiterpene lactone stereochemistry influences herbivore resistance and plant fitness in the field