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11.
12.
The diploid Phoebanthus tenuifolius and the tetraploid P. grandiflorus yielded identical complements of foliar flavonoid aglycones, including the compounds nepetin, jaceosidin, and hymenoxin. Flavonoid data do not resolve the origin of the tetraploid species. The similarity between the flavonoids of Phoebanthus and those earlier reported for Helianthus would support a merger of the two genera. 相似文献
13.
Ferdinand Bohlmann Cornelius Scheidges Laxmi N. Misra Jasmin Jakupovic 《Phytochemistry》1984,23(8):1795-1798
The investigation of three South African Vernonia species afforded minute amounts of five new glaucolides, two monoepoxides and three diepoxides. The structures were elucidated by 1H NMR spectroscopy. The roots of Vernonia sutherlandii contain, in addition to vernonataloide, bergamotene and santalene, minute amounts of the corresponding acetoxy derivatives. 相似文献
14.
The isolation of eucannabinolide and three new sesquiterpene lactones from Schkuhria anthemoidea is reported. The structures and stereochemistries of the new compounds were established by chemical and spectroscopic means. The structure of santhemoidin B was confirmed by X-ray crystallography. 相似文献
15.
A neutral growth inhibitor, isolated from methanolic extracts of sunflower seedlings, was characterized by spectral data as caprolactam. Light-grown se 相似文献
16.
Abrotanella forsterioides afrorded euparin, 6-hydroxytremetone and three 6-hydroxytoxol esters, one of them not being isolated previously. Furthermore a seco-triterpene was isolated. The tribal position of the genus Abrotanella in the Compositae is still an unsolved problem. Morphological investigations suggest that this genus should be transferred from the tribe Anthemideae to the Senecioneae [1,2]. So far two species have been studied chemically; one atforded ent-kaurane derivatives, while both contained euparin and hydroxytremetone [3]. 相似文献
17.
Sanjib Das Robindra N. Baruah Ram P. Sharma Jogendra N. Baruah Palaniappan Kulanthaivel Werner Herz 《Phytochemistry》1983,22(9):1989-1991
Cynaropicrin, 11βH-11,13-dihydrodesacylcynaropicrin, aguerins A and B, isoamberboin and the new guaianolides saussureolide and 11βH-11,13-dihydrodesacylcynaropicrin 8-β-d-glucoside were isolated from Saussurea affinis. 相似文献
18.
In addition to known derivatives, four new sesquiterpene-coumarin ethers were isolated from the roots of Achillea ochroleuca and Artemisia tripartita and identified by 1H and 13C NMR spectroscopy, including lanthanide induced shifts. The new compounds are isofraxidin derived ethers which differ from the previously described derivatives by ring cleavage and methyl migration within the terpenoid unit. The chemosystematic importance of sesquiterpene-coumarin ether accumulation within the two genera is briefly discussed. 相似文献
19.
20.
Yrjö Helariutta Paula Elomaa Mika Kotilainen Pauli Seppänen Teemu H. Teeri 《Plant molecular biology》1993,22(2):183-193
We are approaching corolla differentiation in Compositae by studying the regulation of flavonoid pathway genes during inflorescence development in gerbera. We have cloned a dfr cDNA from a ray floret corolla cDNA library of Gerbera hybrida var. Regina by a PCR technique based on homologies found in genes isolated from other plant species. The functionality of the clone was tested in vivo by complementing the dihydrokaempferol accumulating petunia mutant line RL01. By Southern blot analysis, G. hybrida var. Regina was shown to harbour a small family of dfr genes, one member of which was deduced to be mainly responsible for the DFR activity in corolla. Dfr expression in corolla correlates with the anthocyanin accumulation pattern: it is basipetally induced, epidermally specific and restricted to the ligular part of corolla. By comparing the dfr expression in different floret types during inflorescence development, we could see that dfr expression reflects developmental schemes of the outermost ray and trans florets, contrasted with that of the disc florets. 相似文献