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1.
The major flavonoid glycosides of Sphaerocarpos texanus are luteolin 7-O-glucuronide and 7,4′-di-O-glucuronide. Riella americana and R. affinis both contain apigenin, chrysoeriol and luteolin 7-O-glucuronides but R. americana additionally contains luteolin 3′-O-glucuronide. This finding supports the inclusion of Sphaerocarpaceae and Riellaceae in the order Marchantiales rather than their separation into another order.  相似文献   

2.
The major flavonoids of Marchantia polymorpha var. polymorpha and aquatica are the 7-O-β-d-glucuronides of apigenin and luteolin, luteolin 3′-O-β-d-glucuronide, luteolin 7,3′-di-O-β-d-glucuronide, and the 7,4′-di-O-β-d-glucuronides of apigenin and luteolin. These are accompanied by minor amounts of apigenin, luteolin, luteolin 3′,4′-di-O-β-d-glucuronide and luteolin 7,3′,4′-tri-O-β-d-glucuronide. All the luteolin di- and triglucuronides except the 3′,4′-di- substituted compound are new natural products.  相似文献   

3.
4.
The major flavonoid of Marchantia berteroana is hypolaetin 8-O-β-d-glucuronide. This is accompanied by apigenin and luteolin, isoscutellarein (8-hydroxyapigenin) 8-O-β-d-glucuronide, the 7-O-β-d-glucuronide and -galacturonide of apigenin and luteolin, luteolin 3′-O-β-d-glucuronide and -galacturonide, luteolin 7,3′-di-O-β-d-glucuronide and -galacturonide, luteolin 3′,4′-di-O-β-d-glucuronide and -galacturonide, luteolin 7,4′-di-O-β-d-glucuronide, and hypolaetin 8,4′-di-O-β-d-glucuronide. The isoscutellarein and hypolaetin glucuronides, and the galacturonide flavones are all new natural products.  相似文献   

5.
The flavonoids of 2 samples of Conocephalum conicum gametophyte tissue have been studied, one from U.S.A. and the other from Germany. Common to both samples were vicenin-2, lucenin-2, the 7-O-glucuronides of apigenin, chrysoeriol and luteolin and the previously unknown 7-O-glucuronide 4′-O-rhamnosides of apigenin, chrysoeriol and luteolin. Additionally the German sample contained the 7,4′-di-O-glucuronides of apigenin and luteolin and a new compound, apigenin 7-O-diglucuronide 4′-O-glucuronide. The North American sample contained, additionally, luteolin 7,3′-di-O-glucuronide, luteolin 7-O-glucuronide 3′,4′-di-O-rhamnoside (a new triglycoside) and 2 further derivatives of luteolin 7-O-glucuronide. Evidence is presented for the existence of geographic faces of C. conicum and for the qualitative invariability of the flavonoid patterns with changing season or environment.  相似文献   

6.
The major flavonoids of Marchantia follacea are the 7-O-β-d-glucuronides of apigenin, chrysoeriol and tricin, and apigenin-6,8-di-C-glucoside (vicenin-2). Minor constituents include the rhamnosylglucuronides of the above flavones. Apparent isomerization of the glucuronides on hydrolysis (MeOH-HCl) proved to be due to methylation of the sugar carboxyl group.  相似文献   

7.
A series of ent-sesquiterpenoids corresponding to the optical antipodes of those in higher plants have been isolated from the liverwort Marchantia polymorpha. These sesquiterpenoids provide yet another example of the peculiar stereospecificity of the biogenesis of the liverwort sesquiterpenoids and suggest a special taxonomic position of the liverworts in the plant kingdom.  相似文献   

8.
The major flavonoids in Riccia crystallina are naringenin and its 7-O-glucoside, apigenin 7-O-glucoside and apigenin 7-O-glucuronide and derivatives. Ricciocarpus natans is a rich source of luteolin 7,3′-di-O-glucuronide and also contains the 7-O-glucuronides of apigenin and luteolin and the 3′-O-glucuronide of luteolin. A parallel between the production of biosynthetically simple flavonoids and reduced morphology is evident among these liverworts.  相似文献   

9.
The liverwort, Scapania ornithopodioides, was investigated for sesquiterpene hydrocarbons by utilizing GC and GCIMS and 17 components were identified. Among these, the major component, aromadendrene, and two minor ones, cyclosativene and α-farnesene are reported for the first time as constituents of liverworts. In addition, aromadendrene also occurred in three other Taiwanese liverworts examined.  相似文献   

10.
Flavonoid glycosides have been isolated from a species of the (primitive) order of liverworts, Calobryales, for the first time. The endemic New Zealand species, Haplomitrium gibbsiae, was found to contain acylated derivatives of apigenin-7-glucoside, apigenin 7,4′-diglucoside and isoscutellarein-7-glucoside, all of which are unique to the Bryophytes. The possible taxonomic and phylogenetic relevance of these findings is discussed.  相似文献   

11.
Isoorientin, isoorientin-4′-O-glucoside, gentiopicrin, xanthones with 1,3,5,8 or 1,3,7,8-oxidation pattern have been isolated from five North American Gentiana species (G. affinis, G. algida, G. calycosa, G. detonsa, G. strictiflora) and one South American species (G. cerastioides). Separations were achieved with droplet counter-current chromatography (DCCC) or centrifugally accelerated preparative TLC. The distribution of the isolated compounds within the genus is discussed.  相似文献   

12.
Sophora microphylla, S. prostrata and S. tetraptera are distinguishable from one another by their leaf flavonoids. S. microphylla is distinguished by the present of rhamnosylvitexin and rhamnosylisovitexin and S. tetraptera by the presence of apigenin-7-O-rhamnosylglucoside-4′-O-glucoside and the 7-O-glucosides of apigenin, 7,4′-dihydroxyflavone, luteolin and 7,3′,4′-trihydroxyflavone. Sophora prostrata lacks all these flavonoids, but has several pigments which are common to all three species.  相似文献   

13.
Documentation of amentoflavone O-glucosides as the predominant flavonoid glycosides in both genera of the Psilotaceae clearly distinguishes this family from all other families of vascular plants. Psilotum and Tmesipteris also possess apigenin C- and O-glycosides as common flavonoid types. Apigenin 7-O-rhamnoglucoside occurs in both genera and the previously undocumented apigenin 7-O-rhamnoglucoside-4′-O-glucoside, although identified only in Tmesipteris, may also be present in Psilotum. The existence of flavone C-glycosides in both genera may provide a phytochemical relationship between the Psilotaceae and some ferns. The phylogenetic significance of these results is discussed.  相似文献   

14.
Besides an apigenin- and a luteolin-di-C-glycoside, 5 previously unknown di-C-glycosides of tricetin were identified in the gametophytic and sporophytic tissues of Plagiochila asplenioides. Two of them were new 6,8-di-C-hexopyranosyltricetins, and two were new 6-C- hexopyranosyl-8-C-pentopyranosyltricetins. 6-C-Hexopyranosyl-8-C-pentopyranosyltricetin-5′-methyl ether was also found.  相似文献   

15.
In a leaf survey of 54 specimens of 11 Old World Lupinus species three classes of flavonoids were detected: flavones (in 82%), flavonols (in 36%) and flavone C-glycosides (in 55%). The rough-seeded species were clearly distinguished from the smooth-seeded taxa by the presence of a novel 2′-hydroxyflavone, luteolin and flavone C-glycosides as major leaf constituents and by the absence of flavonols. Within the smooth-seeded species, there are three flavonoid patterns: (a) flavonols only, L. albus; (b) flavones and flavonols, L. luteus, L. hispanicus and L. angustifolius; and (c) flavones only, L. micranthus. L. angustifolius further differed in uniquely producing diosmetin as a major leaf constituent. These divisions coincide exactly with previous groupings based on alkaloidal and morphological data. Amongst the 12 samples of L. angustifolius three chemical races were distinguished and a number of diosmetin glucoside malate esters detected. The flower flavonoid aglycone patterns of the nine Old World species surveyed differed markedly from the corresponding leaf profiles by the presence of flavones: luteolin and apigenin in eight and chrysoeriol in seven species as major constituents, while flavone C-glycosides were found only in trace amount in three species. In a leaf flavonoid survey of 13 representative New World Lupinus taxa, glycoflavones were major leaf components, a variety of methylated flavones were identified and flavonols were absent. The presence of the novel 2′-hydroxyflavone in five New World species may indicate some evolutionary link with the rough seeded taxa of the Old World.  相似文献   

16.
Haplophyllum pedicellatum, H. robustum and H. glabrinum all yielded the known compound gossypetin 8,3′-dimethyl ether 3-rutinoside. In addition the first two species afforded isorhamnetin and its 3-rutinoside. A new glycoside, gossypetin 8,3′-dimethyl ether 3-glucoside was obtained from H. pedicellatum together with the 3-malonylrutinoside, 3-malonylglucoside and 3-galactoside of isorhamnetin plus kaempferol 3-malonylglucoside. H. robustum yielded isorhamnetin 7-glucoside and 3-glucoside and quercetin 3-galactoside, while H. glabrinum was found to contain gossypetin 8-methyl ether 3-malonylrutinoside in addition to kaempferol and isorhamnetin 3-glucoside.  相似文献   

17.
Tibial combs in representatives of the family Cydnidae are described in detail for the first time. The structure was studied in 98 species of 58 genera representing all the subfamilies, among them 16 species were investigated using scanning electron microscopic (SEM) techniques. In addition, Parastrachia japonensis (Scott, 1880) of the family Parastrachiidae, and two species of Dismegistus Amyot and Serville, 1843 (a genus of uncertain systematic position within Pentatomoidea) have also been studied. Morphological terminology is proposed for all the structures connected with tibial combs and the term 'the tibial comb complex' is suggested; its functional, taxonomic and phylogenetic significance is also discussed. The genera of Cydnidae can be classified into two groups depending on differences in the tibial comb complex, when it is present; moreover, its absence in the tribe Scaptocorini (Cephalocteinae) is demonstrated for the first time and is regarded as an autapomorphy of this tribe. Data on the occurrence of tibial combs in other families of true bugs (Hemiptera: Heteroptera) are also briefly reviewed, and an anagenetic trend in their evolution in terrestrial Heteroptera is hypothesized. The presence of tibial combs on all legs is regarded as the most plesiomorphic state.  相似文献   

18.
Chemical studies were carried out on the root of Glycyrrhiza pallidiflora (Leguminosae), a licorice of no medicinal or commercial value. Two isoflavone glycosides, wistin and ononin, were isolated as major constituents from the methanol extract. A series of chromatographic separations of the acetone extract yielded isoflavone aglycones (afromosin, 2′,7-dihydroxy-4′-methoxyisoflavone and formononetin), flavanones (liquiritigenin and 4′,7-dihydroxy-6,8-diprenylflavanone), an isoflavan [(-)-vestitol], a pterocarpan [(-)-medicarpin], chalcones (echinatin and isoliquiritigenin), dibenzoylmethanes (licodione and 2′-O-methyl-licodione), a flavone (4′,7-dihydroxyflavone), a 3-arylcoumarin (2′-7-dihydroxy-4′-methoxy-3-arylcoumarin), and a new isoflav-3-ene (2′-7-dihydroxy-4′-methoxyisoflav-3-ene). The co-occurrence of the retrochalcone echinatin and the biogenetically related licodione and 2′-O-methyl-licodione is of particular interest, and suggests that this species is closely related to G. echinata and G. inflata. The biogenesis of the retrochalcone is also discussed in relation to its significance in the chemotaxonomy of sects Echinatae and Bucharicae of the genus Glycyrrhiza.  相似文献   

19.
The structure of a new ent-longipinane type of sesquiterpenoid, (?)-ent-12β-acetoxylongipin- 2(10)-en-3-one from the liverwort Marsupella aquatica, has been elucidated by spectroscopic and chemical methods.  相似文献   

20.
Robin J. Smith 《Hydrobiologia》2000,418(1):169-184
This paper represents the first study of the morphology of the upper lip (labrum) and hypostome of ostracods using scanning electron microscopy (S.E.M.). There is considerable variation in the upper lip morphology of the 23 species of Cypridoidea (Podocopina) ostracods used in this study. The detail of the upper lip morphology of each species is very distinctive, so that species determination can be made on this feature alone, but it is not useful in diagnosing genera or subfamilies. The hypostome is not readily studied due to the large amounts of dense pseudochaetae (small, setae-like projections) protruding from it and hence is considered not to be a useful taxonomic feature. Several features of the upper lip and mouth region are documented for the first time. Comparisons of the general morphology of the upper lips of Recent ostracods with the upper lip of the fossil ostracod Pattersoncypris micropapillosa Bate, 1972, indicate that there has been very conservative evolution in these features since the Cretaceous.  相似文献   

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