共查询到20条相似文献,搜索用时 15 毫秒
1.
Benjamín Rodríguez 《Phytochemistry》1978,17(2):281-286
From the aerial parts of Sideritis chamaedryfolia six previously known ent-kaurene diterpenoids have been isolated. In addition, seven new labdane derivatives have also been obtained from the same source. The structures of these new natural diterpenoids have been established by chemical spectroscopic means and by correlation with known products. 相似文献
2.
《Phytochemistry》1986,25(11):2569-2572
Three new neo-clerodane diterpenoids, teulepicin, 19-acetylteulepicin and teulepicephin, have been isolated, together with the previously known flavone cirsiliol from the aerial parts of Teucrium lepicephalum. The structures of the diterpenoids were established by chemical and spectroscopic means and by correlation with known substances. In addition, 19-acetylteulepicin and the already known neo-clerodane diterpenoid 19-acetylgnaphalin have been isolated from the species T. buxifolium. 相似文献
3.
《Phytochemistry》1986,25(11):2557-2561
8-O-Foliamenthoyleuphroside and 2′-O,8-O-difoliamenthoyleuphroside, new foliamenthic acid esters of euphroside, and the known iridoid euphroside have been isolated from the leaves and twigs of Clerodendrum incisum. From the roots of the same plant the known iridoid plantarenaloside has been isolated. The taxonomic significance of these findings is discussed. 相似文献
4.
Giuseppe Savona Franco Piozzi Orietta Servettaz Benjamín Rodríguez Francisco Fernández-Gadea Manuel Martín-Lomas 《Phytochemistry》1984,23(4):843-848
From the aerial part of Teucrium flavum subsp. glaucum a new neo-clerodane diterpenoid, teuflavin, and a new 19-nor-neo-clerodane glucoside, teuflavoside, have been isolated, besides the previously known diterpene teuflin. The structures of teuflavin (19-acetoxy-4α,18:15,16-diepoxy-6β-hydroxy-3-keto-neo-cleroda-13(16),14-diene-20,ξ,12S-hemiacetal) and teuflavoside (18-acetoxy-15,16-epoxy-19-nor-neo-cleroda-4,13(16),14-trien-20,12S-olid-6β-yl-2′-O-acetyl-β-d-glucopyranoside) were established by chemical and spectroscopic means and by correlation with known compounds. In addition, the previously known flavone salvigenin has also been obtained from the same source. 相似文献
5.
Jose L. Marco Benjamín Rodríguez Giuseppe Savona Franco Piozzi 《Phytochemistry》1982,21(10):2567-2569
From the aerial parts of Teucrium scorodonia the previously known diterpenoid teupolin I and the flavone luteolin have been isolated. In addition, three new neo-clerodane derivatives have also been obtained from the same source. The structures of these new natural diterpenoids have been established by chemical and spectroscopic means and by correlation with known products. 相似文献
6.
《Biochemical Systematics and Ecology》2005,33(11):1159-1166
Two new and six known flavonoids and two known naphthopyranones have been isolated by chromatographic methods and spectrometrically identified in capitulae and scapes of Eriocaulon ligulatum (Vell.) L.B. Smith (Eriocaulaceae). The presence of naphthopyranones suggests approximation between Eriocaulon and Paepalanthus genus. 相似文献
7.
The new diterpenoid ent-3β-acetoxy-7α,18-dihydroxy-15β,16-epoxykaurane has been isolated from Sideritis biflora. Twelve previously known ent-kaurane derivatives have also been obtained from the same source. 相似文献
8.
Schismatoglottis has been known previously in the Western Hemisphere from two species of sect. Philonotion that occur in northeastern South America. A third species, S. bolivarana, is described and illustrated, from materials collected in the Guayana Highland of Venezuela; it is most closely related to S. americana of Surinam. The possible existence of infraspecific taxa of S. bolivarana is suggested by the differences of ecology and slight morphological variance of the plants at the two widely separated localities where it has been collected. A key to the known American species is presented. 相似文献
9.
Five known isoflavones (daidzein, formononetin, genistein, 5-O-methylgenistein and biochanin A) have been isolated from the leaves and stems of Echinospartum horridum. A sixth compound has been characterised by chemical and spectroscopic methods as the new isoflavone, 5-O-methylbiochanin A. 相似文献
10.
《Lichenologist (London, England)》2001,33(2):103-110
Abstract:Two new species of lichens are described from the Iberian Peninsula. Halecania giraltiae is the first sorediate saxicolous species known in the genus and has been collected growing on lichens and sometimes directly on rock in localities from northern Portugal to central Spain. Catillaria fungoides, a sorediate, corticolous representative of the C. nigroclavata group, is known from southern Portugal and northern Spain. 相似文献
11.
Malte Elbrächter 《Helgoland Marine Research》1998,52(3-4):235-242
Flagellate species have been shown to survive transocean passage by ballast water and the large dinoflagellateGymnodinium catenatum was introduced from Japanese to Tasmanian waters in this way.Gymnodinium mikimotoi—better known asGyrodinium aureolum—andFibrocapsa japonica as well asAlexandrium leeii are good candidates to have been introduced recently. Species which seem to have been introduced recently into the North Sea but apparently are transported from adjacent seas by currents into the region areGymnodinium chlorophorum andAlexandrium minutum. Species reported as introduced due to misidentifications areGymnodinium catenatum andLepidodinium viride. Under other names the speciesProrocentrum minimum, Prorocentrum redfieldii, andHeterosigma akashiwo have been known for a long time in the North Sea. The recent reports of threeChattonella species may be either due to introduction or they have been overlooked. The reasons why the introduction of flagellates into coastal North Sea waters is difficult to prove will be discussed. 相似文献
12.
Thirteen new labdane-type diterpenes have been isolated from the seeds of Sciadopitys verticillata together with six known ones, sciadin, sciadinone, dimethyl sciadinonate, lambertianic acid and its methyl ester and trans-communic acid. Their structures have been determined by chemical and spectral methods. 相似文献
13.
Acacipetalin, previously known only from the African legumes Acacia sieberiana var. woodii and Acacia hebeclada, has been isolated from an American species of the genus, Acacia constricta. 相似文献
14.
Yoshinori Asakawa Masao Toyota Tsunematsu Takemoto Claude Suire 《Phytochemistry》1979,18(8):1355-1357
Four novel secoaromadendrane-type sesquiterpene hemiacetals, plagiochilines C, D, E and F, together with the previously known (?)-bicyclogermacrene, have been isolated from the liverwort, Plagiochila asplenioides and their structures have been spectroscopically elucidated. From Plagiochila semidecurrens plagiochilines A and C have been obtained along with (?)-bicyclogermacrene and its related sesquiterpene hydrocarbons. 相似文献
15.
Ivan Addae-Mensah Frank G. Torto Isaac V. Oppong Ian Baxter Jeremy K.M. Sanders 《Phytochemistry》1977,16(4):483-485
A novel alkaloid, N-isobutyl-trans-2-trans-4-eicosadienamide, has been isolated from the fruits of Piper guineense and fully characterized. The structure of the compound has been confirmed by an unambiguous synthesis of the tetrahydro derivative. The known alkaloid, δαβ-dihydropiperine has also been isolated and the position of the double bond in this compound confirmed by the use of an NMR shift reagent. 相似文献
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18.
Two new derivatives of royleanone, 7α-ethoxyroyleanone and 7α-ethoxy-12-O-methyl-royleanone, besides the previously known diterpenes royleanone, 6,7-dehydroroyleanone, 7α-acetoxyroyleanone and inuroyleanol, have been isolated from the root of Salvia lavandulaefolia. The triterpenoid O-acetyloleanolic aldehyde has also been obtained from the same source. 相似文献
19.
The alkaloids present in the seeds of four Erythrina species, E. brucei, E. cochleata, E. thollonia and E. caribaea have been screened by GC/MS. A new alkaloid, erythrocarine, has been isolated from E. caribaea and characterized as a methylenedioxy analogue of the known dienoid alkaloids erysoline and erysonine. 相似文献
20.
《Harmful algae》2017
Euglena sanguinea is known to produce the alkaloid toxin euglenophycin and is known to cause fish kills and inhibit mammalian tissue and microalgal culture growth. An analysis of over 30 species of euglenoids for accumulation of euglenophycin identified six additional species producing the toxin; and six of the seven E. sanguinea strains produced the toxin. A phylogenetic assessment of these species confirmed most taxa were in the Euglenaceae, whereas synthesis capability apparently has been lost in the Phacus, Eutreptiella, and Discoplastis branches. 相似文献