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The major sesquiterpenes in the foliage of Dacrydium cupressinum are α-longipinene, longifolene, longibornyl acetate, caryophyllene, caryophyllene oxide, humulene, α- and β-selinene, β- and δ-elemene, aromadendrene and the rare 9βH-caryophyllene. Sesquiterpene levels vary greatly from tree to tree. As this variation is largely independent of environmental factors, genetic control is proposed. Longifolene and α-longipinene levels are closely correlated, as are those of caryophyllene and humulene. The biosynthetic implications of these correlations are discussed. 相似文献
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Plant growth inhibitors of the podolactone-type have been detected by bioassay in ten further species of Podocarpus. The most active extracts in P. elatus were from root tips, root cortex and very young leaves. Fifty-seven other conifers were examined for this type of activity. It is present in Cephalotaxus harringtonia where it is probably due to the presence of harringtonolide, which, like momilactone B from rice husks, shows podolactone-type inhibition of the growth of etiolated dwarf pea hooks. 相似文献
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A survey of the biflavonyls in the leaves and branchlets of all three sections of the genus Dacrydium s.l. revealed a complex mixture of amentoflavone and its partial methyl ethers and hinokiflavone in most species. A group of three species in section C, however, were characterised by cupressuflavone derivatives as the major biflavone constituents. The results are used to discuss proposals for revised generic boundaries. 相似文献
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Jayr de Paiva Campello Sebastião Ferreira Fonseca Ching-Jer Chang Ernest Wenkert 《Phytochemistry》1975,14(1):243-248
Sitosterol and the following terpenic compounds have been isolated from the bark of Podocarpus lambertius: 3β-hydroxytotarol, 4β-carboxynortotarol, and macrophyllic and lambertic acids. The leaves yielded sitosterol, stigmastan-3β,5α-diol-6-one, isopimaric acid, phyllocladene, isophyllocladene, 8,9-abieten-15-ol and 17-isophyllocladenol. 相似文献
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Stephen A. Matlin M.Amelia Prazeres Magalis Bittner Mario Silva 《Phytochemistry》1984,23(12):2863-2866
Rimuene and nubigenol have been identified in Podocarpus saligna for the first time, and the structures of three new norditerpene dilactones, salignones K, L and M, isolated from this species have been elucidated. 相似文献
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Johnny A. Hembree Ciung-Jer Chang Jerry L. McLaughlin John M. Cassady Daniel J. Watts Ernest Wenkert Sebastiko Ferreira Fonseca Jayr De Paiva Campello 《Phytochemistry》1979,18(10):1691-1694
The cytotoxic norditerpene dilactones nagilactone F and its new congener nagilactone G have been isolated from the bark constituents of Podocarpus milanjianus and Podocarpus sellowii. The diterpenes totarol, 19-oxototarol and macrophyllic acid were also isolated. 相似文献
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Podocarpophyllum Gomolitzky is studied in detail from the type locality Angren (Uzbekistan, Middle Jurassic). Emended diagnoses of the genus and its type species P. singulare Gomolitzky are provided. For the first time, members of the genus are reported from the Lower Jurassic of the Mangyshlak Peninsula (western Kazakhstan), where P. kazachstanicum sp. nov. is described, and from the Middle Jurassic of the eastern Ural Mountains, where P. mesozoicum (Kiritchkova) comb. nov. is established. The epidermal morphology of the genus Podocarpophyllum is compared with that of fossil and modern members of the Podocarpaceae. 相似文献
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红豆杉科、三尖杉科和罗汉松科植物叶片结构的比较观察 总被引:8,自引:0,他引:8
扫描电镜和光镜下的叶表皮特征以及叶片解剖结构的研究结果,支持在红豆杉科内建立白豆杉属的处理方式;赞同在三尖杉属内建立篦子三尖杉组,叶片解剖结构方面,三尖杉科和红豆杉科的穗花杉属的相似之处颇多。而叶表皮形态特征方面又表现为三尖杉科和罗汉松科更加接近。反映了出了红豆杉科、三尖杉科和罗汉松科之间的密切而又复杂的系统关系。 相似文献
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