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1.
Oleoresins from different species of Copaifera are used in popular medicine and in the cosmetics industry without giving due consideration to the differences between them. Comparison of the compositions of oleoresins from Copaifera guianensis Desf. and Copaifera duckei Dwyer, species now examined, and of the better known Copaifera multijuga Hayne, all of common occurrence in Brazilian Amaz nia, shows that significant chemical variation occurs not only between species but also within a given species and in an individual tree source. 相似文献
2.
A nor-lignan and two sesquiterpenes, along with six known compounds, have been isolated from the medicinal plant Cremanthodium ellisii. Their structures were determined on the basis of spectral evidence, especially 2D NMR (1H-1H COSY, HMQC, HMBC). 相似文献
3.
Ferdinand Bohlmann Michael Wallmeyer Jasmin Jakupovic Jürgen Ziesche 《Phytochemistry》1983,22(7):1645-1651
The investigation of several Osteospermum species afforded in addition to known compounds three diterpenes from the rare cassane type, two further sandaracopimarene derivatives, two 6-desoxyglucosides of cubebol and 13-hydroxycaryophyllene, respectively, an isomer of 7-hydroxycalamenene, two p-hydroxyacetophenone derivatives derived from toxol, a thymol derivative and the palmitates of lupeol, taraxasterol and 3β,20-dihydroxydammarene. The structures were elucidated by spectroscopic methods. The chemotaxonomy of the genus is discussed briefly. 相似文献
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5.
Five new notonipetrone-like sesquiterpenes have been isolated from the roots of Senecio kleinia and their structures elucidated. 相似文献
6.
The leaves and the trunk barks of Magnolia watsonii afforded two biosynthetic intermediates of dehydrocostuslactone (watsonol A and watsonol B) along with the neolignans, magnolol, hōnokiol and obovatol, and the aporphine alkaloids, liriodenine and asimilobine. 相似文献
7.
Three sesquiterpenes, pinguisanin, pinguisanolide and pinguisenal, have been isolated from the liverwort, Ptilidium pulcherrimum. These pinguisane- 相似文献
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9.
Induction of plant resistance by herbivory is a complex process, which follows a temporal dynamic and varies spatially at
the within-plant scale. This study aimed at improving the understanding of the induction process in terms of time scale and
within-plant allocation, using apple tree seedlings (Malus × domestica) as plant model. Feeding preferences of a leaf-chewing insect (Spodoptera littoralis) for previously damaged and undamaged plants were assessed for six different time intervals with respect to the herbivore
damage treatment and for three leaf positions. In addition, main secondary defense compounds were quantified and linked to
herbivore feeding preferences. Significant herbivore preference for undamaged plants (induced resistance) was first observed
3 days after herbivore damage in the most apical leaf. Responses were delayed in the other leaf positions, and induced resistance
decreased within 10 days after herbivore damage simultaneously in all tested leaf positions. Chemical analysis revealed higher
concentrations of the flavonoid phloridzin in damaged plants as compared to undamaged plants. This indicates that herbivore
preference for undamaged apple plants may be linked to phloridzin, which is the main secondary metabolite of apple leaves.
The observed time course and distribution of resistance responses within plants contribute to the understanding of induction
processes and patterns, and support the optimal defense theory stating young tissue to be prioritized. Moreover, induced resistance
responses occurred also basipetally in leaves below the damage site, which suggests that signaling pathways involved in resistance
responses are not unidirectional. 相似文献
10.
The banana aphid, Pentalonia nigronervosa Coquerel (Hemiptera: Aphididae), infests banana (Musa spp.) worldwide. Pentalonia nigronervosa is the vector of Banana bunchy top virus (family Nanoviridae, genus Babuvirus) the etiological agent of Banana bunchy top disease (BBTD). BBTD is currently the most serious problem affecting banana in Hawaii. Despite the importance of this vector species, little is known about its biology or ecology. There are also no sampling plans available for P. nigronervosa. We conducted field surveys to develop a sampling plan for this pest. Ten plots were surveyed on seven commercial banana farms on the island of Oahu, HI, for the presence of P. nigronervosa on banana plantlets. We found aphids more frequently near the base of plants, followed by the newest unfurled leaf at the top of the plant. Aphids were least likely to be located on leaves in between the top and bottom of the plant. Aphid infestation on surveyed plots ranged from 8 to 95%. We developed a sequential binomial sampling plan based on our surveys. We also discovered that the within-plant distribution of P. nigronervosa is an important factor to consider when sampling for this pest. Our sampling plan will assist in the development of sustainable management practices for banana production. 相似文献
11.
The investigation of further Senecio species gave, in addition to known compounds, two new sesquiterpenes, an eremophilane and a eudesmane derivative. 相似文献
12.
《Phytochemistry》1986,25(12):2883-2886
Four new carotane sesquiterpenes have been isolated from Ferula linkii. They have been identified as the 5-isovalerate of isolancerotriol, the 5-isovalerate and 5-angelate of isolancerotetrol, and the 5-isovalerate of epoxyisolancerotetrol. 相似文献
13.
The South African plant, Senecio oxyodontus, contained in addition to known compounds several new sesquiterpenes, which were all of the bisabolene type. The structures were elucidated by spectroscopic methods and some chemical transformations. The constituents were closely related to those from one other South African Senecio species and in contrast to most Senecio species which contain very different structural types, mainly of the furanoeremophilanes type. 相似文献
14.
Four seco-prezizaane sesquiterpene lactones, 14-O-n-butyrylfloridanolide, 3,4-dehydrofloridanolide, 3,6-dideoxy-10-hydroxypseudoanisatin, and 2-O-n-butyrylpseudomajucin were isolated from the pericarps of Illicium merrillianum. Their structures were determined by spectroscopic methods. 相似文献
15.
The petroleum ether extract of the stem bark of Amoora rohituka afforded two novel guaiane-derived sesquiterpenoids, 6beta,7beta-epoxyguai-4-en-3-one (1) and 6beta,7beta-epoxy-4beta,5-dihydroxyguaiane (2). The structures of 1 and 2 were determined by extensive NMR and MS analyses and by comparison of their spectral data with related compounds. The relative stereochemistry of the asymmetric centers in 1 and 2, except at C-5 of 2, were determined by selective 1D-NOESY experiments. 相似文献
16.
Four sesquiterpene lactones including an eremophilenolide dimer, named as biligulaplenolide, 1, 8beta-hydroxy-1-oxo-(14alpha,15alpha eremophil-7(11),9(10)-dien-12,8alpha-olide, 2, 1-hydroxy-2-oxo-(14alpha,15alpha eremophil-1(10),7(11),8(9)-trien-12,8-olide, 3, 4alpha,8beta,9alpha-trihydroxy- 5alphaEta-7(11)-eudesmen-12,8alpha-olide, 4, along with two known ones, 10alpha-hydroxy-1-oxo-eremophil-7(11),8(9)-dien-12,8-olide, 5, and furanoeremophil-1(10)-ene-2,9-dione, 6, were isolated from the underground organs of Ligularia platyglossa (Franch.) Hand.-Mazz. Their structures were elucidated by spectroscopic methods including single-crystal X-ray diffraction analysis (2 and 3). Their in vitro cytotoxicities against seven cancer cell lines (BGC-823, A549, HL-60, B16, SMMC-7721, BEL7402, Hela) were evaluated. Compounds 2, 3, 5 showed cytotoxic activities on HL-60 cancer cells with IC50 in the range of 24.0 to 51.1 microM, whereas compound 3 exhibited only weak cytotoxic activity against the B16, BEL7402 and Hela cancer cells. Flow cytometric analysis indicated that compound 3 induces Hela cells to apoptotic death after 48 h treatment with 0.38 mM of this compound. 相似文献
17.
《Phytochemistry》1986,25(5):1161-1165
Five new carotane sesquiterpenes have been isolated from Ferula linkii. These were the 3-angelate of felikiol, angelate- and epoxyangelate of webiol, 5-isovalerate of ferutriol and veratrate of lancerotol, and the already known p-hydroxybenzoate- and p-methoxybenzoate of lancerotol. The structures of the 3-angelate of felikiol and epoxyangelate of webiol were determined by X-ray analysis. 相似文献
18.
Six new sesquiterpenes of the guaiane and isopatchoulenone types have been isolated from the Chilean plant Pleocarphus revolutus. Of these, the compound hydroxy-isopatchoulenone and related esters showed cytotoxicity towards TLX5 mouse mammary lymphoma cells. 相似文献
19.
The roots of Artemisia filifolia afforded in addition to known compounds an oxo-longipinane, a longibornan endoperoxide, two seco-longibornane derivatives and a himachalene derivative. The structures of the new sesquiterpenes were elucidated by several chemical transformations and by NMR spectroscopic investigations. Possible biogenetic pathways are discussed briefly. 相似文献
20.
Ferdinand Bohlmann Nezhun Ates Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1982,21(11):2691-2697
Artemisia douglasiana afforded, in addition to known compounds, two new C14-acetylenes, five longipinene derivatives, three nerolidol derivatives, a lactone and a ketone with a new carbon skeleton and lavendulol-2-methylbutyrate. The structures were elucidated by spectroscopic methods and some chemical transformations. The configurations of several oxo longipinene-7, 9-di- and 7, 8, 9-triesters isolated previously were corrected. The biogenesis of the new lactones is discussed briefly. 相似文献