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1.
The aerial parts of U. anethoides afforded, in addition to new nerolidol derivatives, a new germacranolide. The structure could only be elucidated by formation of the corresponding pyrazoline derivative and by comparison of the 1H NMR data with those of similar pyrazolines. The aerial parts of U. alpina also contain a new nerolidol derivative and, in addition to the known 9β-hydroxycostunolide, a new eudesmanolide. The roots of all species contain furanosesquiterpenes, which are also present in related genera.  相似文献   

2.
Brachymeris montana afforded several furanosesquiterpenes two of them not being isolated previously. The structures were elucidated by highfield 1H NMR spectroscopy. The present isolation of these characteristic sesquiterpenes from one of the woody South African genera of the Anthemideae is of chemotaxonomic interest.  相似文献   

3.
A new mixture of epimeric isomers furanosesquiterpenes (1 and 1a), together with two known furanosesquiterpenes were isolated from Xanthopappus subacaulis, which was used as Tibetan medicine in China. The structures of these compounds were elucidated on the comprehensive analysis of spectroscopic data including UV, IR, MS and NMR. The biosynthetic pathway of furanosesquiterpenes is proposed and the chemotaxonomic significance of these compounds is also discussed.  相似文献   

4.
Within South African Asteraceae-Anthemideae there is a group of genera containing furanosesquiterpenes rather than the common polyacetylenes. Of these genera, Asaemia (Harv.) Ham. ex Benth. & Hook., Athanasia L., Eumorphia DC., Gymno-pcnfzia Benth., Phymaspermum Less. and Sfilpnophyfon Less. have been investigated morphologically especially with respect to fruit structure. As a result of the investigations Stilpnophyton has been reduced to synonomy under Athanasia L. emend. Källersjö (with 36 spp.) and five species of Athanasia , together with Phaeocephalus S. Moore., are placed in the revived genus Hymenolepis Cass. (with 7 spp.). Brachymerk DC. and four misplaced species of Aihanasia are included in Phymaspermum Less. emend. Källersjö (with 17 spp.). Nine other misplaced species of Athanasia and one Pentzia Thunb. species have been described as a new genus Inulanihera Källersjö (with 10 spp.), a group without furanosesquiterpenes. The two monotypic genera Asaemia and Gymnopentzia , and Eumorphia (with 6 spp.) remain unchanged. The interrelationships of the genera possessing furanosesquiterpenes are shown in a cladogram. There are 25 new combinations in Afhanasia, Znulanthera, Hymenolepis and Phymaspermum .  相似文献   

5.
The investigation of nine further Baccharis species afforded in addition to known compounds three new p-coumaric acid derivatives, a new eudesmane aldehyde and a clerodane dilactone. The structures are elucidated by spectroscopic methods. The chemotaxonomic situation in this genus is still not very clear. The compounds isolated are not very characteristic, as very similar ones are present in other genera of the tribe to which Baccharis belongs.  相似文献   

6.
The investigation of Ursinia nana afforded in addition to the typical known furanosesquiterpenes two new compounds, probably both derived from the  相似文献   

7.
Re-investigation of Wunderlichia mirabilis afforded three new modified eudesmanolides of the same type isolated previously from an Onoseris species, and minute amounts of a germacranolide for which a structure only could be proposed. Actinoseris polymorpha also contained a new germacranolide, the angetate of desacetyllaurenobiolide. Structures were elucidated by spectroscopic methods and by some chemical transformations. The significance of these findings is discussed briefly.  相似文献   

8.
An investigation of Inula helenium, I. royleana, I. salicina and I. bifrons afforded in addition to known sesquiterpene lactones 20 new lactones, the eudesmanolides 3, 6 and 8–12, the germacranolides 14–18 and 20–22, the guaianolides 23 and 25, the pseudoguaianolide 26, the xanthanolides 28 and 32 and the cyclopropane analogue 30. Structures and configurations of these new compounds were established by extensive PMR studies and by some chemical transformations. Some of the investigated species contain besides the widely distributed pentaynene 33 several known thymol derivatives together with a new one (40).  相似文献   

9.
A new genus of Metopiinae, Ojuelos Khalaim, gen. n., with a single species, Ojuelos juachicus Khalaim & Ruíz-Cancino, sp. n., is described from Jalisco Province in central Mexico. Ojuelos belongs to the group of three genera (Cubus Townes & Townes, Colpotrochia Holmgren and Triclistus Förster) having a high lamella separating the antennal sockets and reaching the median ocellus (this lamella possesses a dorsal groove in it, just below the median ocellus), but differs from these genera primarily by 1) face and clypeus not convex in lateral view, 2) face separated from clypeus by a shallow transverse impression, 3) mandible with lower tooth very strongly reduced, 4) flagellomeres of antenna strongly transverse, and 5) dorsal carinae of propodeum reduced. A portion of the key to the genera of Metopiinae is provided to distinguish the new genus.  相似文献   

10.
Two new genera, Repkinella and Aristotreta, and five new species from the class Lingulata (Brachiopoda) are described from the Upper Cambrian olistolith limestone enclosed in the Upper Ordovician olistostrome from the Agyrek mountains (northeastern Kazakhstan). The family Curticiidae Walcott et Schuchert is referred to the order Lingulida, not order Acrotretida, where it was previously placed.  相似文献   

11.
The investigation of Gnaphalium undulatum afforded two new labdane derivatives, one having a new carbon skeleton, and a new flavonol. Furthermore, an unknown diterpene lactose is present; its structure, however, could not be elucidated. The only American species investigated contains the trans-isomer of the precursor of the acetylenic chloroenol ether, which is widespread in Gnaphalium and in related genera. The chemotaxonomic situation is discussed briefly.  相似文献   

12.
In the Oriental Region, the large, basically Northern Hemisphere family Trichopolydesmidae is shown to currently comprise 18 genera and 43 species. Based mainly on gonopod structure, all of them, as well as the whole family, are (re)diagnosed, including five new genera and seven new species. These new taxa are keyed, also being the first to be described from Indochina in general and from Vietnam in particular: Aporodesmella gen. n., with three species: A. securiformis sp. n. (the type species), A. similis sp. n. and A. tergalis sp. n., as well as the following four monotypic genera: Deharvengius gen. n., with D. bedosae sp. n., Gonatodesmus gen. n., with G. communicans sp. n., Helicodesmus gen. n., with H. anichkini sp. n., and Monstrodesmus gen. n., with M. flagellifer sp. n. In addition, Cocacolaria hauseri Hoffman, 1987, hitherto known only from New Ireland Island, Papua New Guinea, is redescribed based on material from Vanuatu whence it is recorded for the first time. One of the new genera, Gonatodesmus gen. n., provides a kind of transition or evolutionary bridge between Trichopolydesmidae and Opisotretidae, thus reinforcing the assignment of these two families to the single superfamily Trichopolydesmoidea.  相似文献   

13.
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15.
Calea zacatechichi yielded the sesquiterpene lactone zexbrevin and a new analog, several analogs of neurolenin B including calein A, two analogs of budlein A and the flavones acacetin and O-methylacacetin. Calea urticifolia contained additional analogs of neurolenin B as well as a series of epoxidation products. Structures were established by spectrometric techniques. The results are contrasted with previous findings.  相似文献   

16.
Two new species of oribatid mites, Lepidozetes acutirostrum sp. n. and Scutozetes clavatosensillus sp. n., are described from Nepal. The genera Lepidozetes and Scutozetes are recorded for the first time for the Oriental region. The identification keys to the known species of these genera are provided.  相似文献   

17.
Two genera of Korean Orthocentrinae, Gnathochorisis and Symplecis, are reviewed, and keys to species of these genera are provided here. Two new species, Gnathochorisis fuscipes Humala & Lee, sp. n. and Gnathochorisis koreensis Humala & Lee, sp. n. are described from South Korea. The current state of the taxonomy of Eastern Palaearctic orthocentrines is briefly discussed.  相似文献   

18.
The roots of Platycaroha glomerata contain five thiophenes which have been isolated before only from Berkheya species. A new diol is also present. The aerial parts contain two new germacrolides, their structures being elucidated by spectroscopic methods. On the basis of the identification of these root constituents, this plant appears to be closely related to other genera in the tribe Arctotideae.  相似文献   

19.
The composition of the essential oils from the seeds of eight species and the leaves of two species of the New Zealand Apiaceae was determined. Gingidia and Scandia species provided seed oils in high yield (>6%) that contained high proportions of phenylpropanoids. Anisotome haastii provided an oil in moderate yield (1.7%), over half of which was comprised of monoterpenoids and no phenylpropanoids. The four Aciphylla species afforded seed essential oils in low yield (0.5%). Three of these contained neither terpenoids nor phenylpropanoids, but contained fatty acids instead. The oil from Aciphylla squarrosa was different as it contained an abundance of phenylpropanoids. The composition of the leaf essential oils of Scandia rosifolia and Gingidia montana differed significantly from those of the corresponding seed oils. Outstandingly, the seed essential oil of G. montana contained 62% estragole and that of Scandia geniculata contained 79% dill apiole. The results of this present work support the conclusions of Mitchell et al. (1998), about the taxonomy of these genera that were drawn from their work with ribosomal DNA sequences viz., that the Gingidia and Scandia genera were closely related to each other and that the Anisotome and Aciphylla genera were not closely related to each other, but were weakly related to the Gingidia and Scandia genera.  相似文献   

20.
The family Heliodiscidae Haeckel, 1881, which includes five genera, is reviewed. New methods of investigation are applied to the inner structure of Cretaceous spherical radiolarian skeletons, which reveal numerous taxa with an eccentric microsphere. Three new species, Astrophacus marinae sp. nov., Excentrosphaerella kovalenkovi sp. nov., and Excentrosphaerella kurilovi sp. nov., are described. The eccentric position of the microsphere suggests that these forms are nontypical Mesozoic radiolarians or new representatives of the family Heliodiscidae Haeckel, 1881, which was previously recorded in the Cenozoic.  相似文献   

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