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11.
The aerial parts of Daphne sericea yielded two new flavonoids, luteolin 7-methyl ether 5-β-d-glucoside and luteolin 7,3′-dimethyl ether 5-β-d-glucoside, as well as luteolin 7-methyl ether, isovitexin, apigenin and its 7-β-d-glucoside. 相似文献
12.
Russell J. Molyneux James N. Roitman Mabry Benson Robert E. Lundin 《Phytochemistry》1982,21(2):439-443
The 13C NMR spectra of nine pyrrolizidine alkaloids of the macrocyclic diester type, seven of the corresponding N-oxides and of the parent base retronecine have been recorded and the signals assigned. The 13C NMR signals were found to be sensitive to structural variation in both the diester moiety and the heterocyclic ring system, providing useful information for structural elucidation, particularly when the 1H NMR spectra may be difficult to interpret. 相似文献
13.
The aerial parts of Passiflora serratodigitata yielded 5,7-dihydroxy-4-phenylcoumarin, its 7-β-glucoside and the known C-glycosylflavones 2″-xylosylvitexin, 2″-xylosylisovitexin, vitexin, isovitexin, a vicenin, and orientin. The known flavone chrysin was also isolated. This is the first report of neoflavonoids in the family Passifloraceae. 相似文献
14.
Samuel B. Jones Jr. William C. Burnett Jr. Nancy C. Coile Tom J. Mabry M. F. Betkouski 《Oecologia》1979,39(1):71-77
Summary Sesquiterpene lactone glaucolide-A from Vernonia, incorporated in the rearing diets of five species of Lepidoptera, significantly reduced the rate of growth of larvae of the southern armyworm, Spodoptera eridania; fall armyworm, S. frugiperda; and yellowstriped armyworm, S. ornithogalli. Quantitative feeding tests demonstrated that decreased feeding levels and reduced growth resulted from ingestion of a sesquiterpene lactone. Ingestion of glaucolide-A increased the number of days to pupation in four of the species. In the southern armyworm, it significantly reduced pupal weight. Glaucolide-A decidedly reduced percentage of survival of southern and fall armyworms. Yellow woollybear, Diacrisia virginica, and cabbage looper, Trichoplusia ni, larvae were essentially uneffected by the ingestion of the sesquiterpene lactone. Sesquiterpene lactones adversely affect growth rate and survival of certain insects that feed upon plants containing them. They apparently function as defensive products, screening out a portion of the potential herbivores.Vernonieae: Compositae 相似文献
15.
The structure for trichoclin, (E)-8-(3-methyl-4-hydroxy-2-butenyloxy)-psoralen, a new furocoumarin isolated from Trichocline incana, has been established. Phellopterin and isopimpinellin were also obtained. The new side chain of trichoclin was confirmed by synthesis. 相似文献
16.
以化学纯饲料饲养北京的桃蚜 总被引:4,自引:0,他引:4
应用修改后的Dadd和Mitter(1966)全纯饲料配方配制成人工饲料饲养定居在北京温室烟草上的桃蚜 Myzus persicae可完成生活史井连续饲养3代。本文描述饲料配制、饲养和取食量测定的方法。这3代初羽化无翅孤雌胎生雌蚜的平均体重分别为:440±90.7μg,264±104.9μg和312±127.9μg。用放射性同位素稀释法测定取食量的结果得悉若虫期的总取食量每蚜约为1.74μg,相当于1.16μl。 相似文献
17.
Two diterpene carboxylic acids, one a new kaurenoid derivative and one the previously characterized labdane, ()-cis-ozic acid, as well as a 相似文献
18.
19.
Hassan-Fahmi Aly Hans Geiger Ursula Schücker Hugh Waldrum George Vander Velde Tom J. Mabry 《Phytochemistry》1975,14(7):1613-1615
Ten glycosides of kaempferol and quercetin, including the hitherto unknown kaempferol and quercetin 3-rutinoside-7-rhamnosides, have been isolated from Equisetum silvaticum L. 相似文献
20.
Two new flavonols, 5,7,4′-trihydroxy-3,6,8,3′-tetramethoxyflavone and quercetagetin 3,5,6,3′-tetramethyl ether, were identified in leaves of Chrysothamnus viscidiflorus. Eight known methyl ethers based on kaempferol, quercetin or their 6-hydroxy derivatives were also detected. 相似文献