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1.
The investigation of Eremanthus crotonoides afforded in addition to known compounds three new furanoheliangolides, while from E. glomerulatus six new furanoheliangolides and eremantholides were isolated. From the aerial parts of Chresta sphaerocephala a new guaianolide was obtained, while the roots contained known furanoheliangolides. The chemotaxonomy of the subtribe Lychnophorinae is discussed briefly.  相似文献   

2.
The investigation of three Hemizonia species afforded in addition to known compounds seven new labdane derivatives, all derived from labd-13-en-15-ol. The absolute configuration of these diterpenes was determined by degradation of the triol by periodate cleavage, which afforded a known norditerpene ketone. From H. fitchii two new chromene esters and the cis-isomer of a known coumarate were isolated. H. congesta afforded in addition to labdane derivatives a hydroxycubebol.  相似文献   

3.
Examination of Liatris mucronata gave the known 15-hydroxylated heliangolides liscundin, liscunditrin, punctaliatrin and two new closely related heliangolides. Liatris acidota furnished six new similar but 15-deoxygenated heliangolides as well as euparin and 3β-acetoxytaraxaster-20-en-30-aldehyde. Liatris aspera gave a known glycosidic germacradienolide and a new germacradienolide as well as several known flavones and a known benzofuran. Structures were established by spectroscopic methods and chemical transformations.  相似文献   

4.
One new and 5 known flavone C-glycosides were isolated from leaves and stems of Coronilla varia. The new compound was shown to be isoorientin 2″-O-rhamnoside. The known compounds were isovitexin, isoorientin, isovitexin 4′-O-glucoside, isoorientin 4′-O-glucoside, and isoorientin 7-O-glucoside.  相似文献   

5.
One previously named and two new species of the tineid genus Erechthias Meyrick are described and illustrated from the small, remote, mid-Atlantic Ascension Island. With these additions the Lepidoptera fauna of Ascension now totals 38 known species. Little is known regarding the biology of the two new species of Erechthias, and none of the species has been reared from larvae from Ascension. Erechthias minuscula (Walsingham) is a widespread, largely pantropical species first described from the West Indies. Larvae of Erechthias minuscula are known to be scavengers on a wide variety of dead plant material. Erechthias ascensionae,new species, is one of two species of Erechthias now known to be endemic to the island. The other endemic species, Erechthias grayi, new species, is further remarkable in having wing reduction occurring in both sexes. It is one of the few species of Lepidoptera known where this extreme of brachyptery involving both sexes has evolved. The larvae of Erechthias grayi are believed to be lichenivorous, and larval cases suspected to represent this species are illustrated.  相似文献   

6.
Two new eurypterid species, Adelophthalmus kamyshtensis sp. nov. and Adelophthalmus dubius sp. nov., are described from the Middle Devonian of Khakassia. The new species are among the earliest known members of the genus Adelophthalmus and the earliest members of this genus known outside Europe and North America.  相似文献   

7.
Eleven flavonoids including three new glycosides were isolated from Brickellia chlorolepis and one new and nine known flavonoids were obtained from B. dentata. The new glycosides from B. chlorolepis are 6-methoxykaempferol 3-rhamnoglucoside, spinacetin 3-rhamnogalactoside and veronicafolin 3-rhamnoglucoside. The known compounds identified from B. chlorolepis are patuletin, casticin, artemetin, eupatolitin 3-galactoside, quercetin 3-rhamnogalactoside, rutin, isorhamnetin 3-galactoside and eupatin 3-SO3Ca12. B. dentata contains the new glycoside eupalitin 3-galactoside and nine known compounds: pectolinarigenin, salvigenin, eupafolin, cirsiliol, eupatorin, eupatolitin, eupatolitin 3-glucoside, eupatolitin 3-galactoside and eupatin.  相似文献   

8.
The investigation of seven Bolivian Senecio species afforded in addition to known compounds five new furanoeremophilanes, two C10-amides, a new isoeugenol ester and the isomer of pterophorin. The structures are elucidated mainly by spectroscopic methods. While most of the new compounds are closely related to those isolated before from Senecio species, four of them are unusual. Another is a new type of a furanoeremophilane; its biogenesis however, can be explained easily from known types.  相似文献   

9.
《Phytochemistry》1987,26(10):2753-2757
In addition to three known thymol esters and five known sesquiterpene lactones, two new germacrolides and a new diterpene diester were isolated from the dichloromethane extract of the aerial parts of Piptothrix sinaloae. Structures for the new compounds were elucidated by chemical transformations and spectral methods. The current taxonomic status of P. sinaloae is discussed on the basis of both morphological and secondary metabolite data.  相似文献   

10.
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   

11.
In addition to the known alkaloids kokusaginine, skimmianine, γ-fagarine and a lignan, justicin B, the aerial parts of Haplophyllum buxbaumii afforded three new alkaloids: 4,5,6-trimethoxyfuroquinoline, 4,5,7-trimethoxyfuroquinoline and N-hydroxymethylflindersine. The structures of the known and the new compounds were assigned by spectral methods.  相似文献   

12.
《Phytochemistry》1986,25(7):1663-1667
The aerial parts of Artemisia douglasiana afforded, in addition to some known sesquiterpene lactones, 22 new closely related guaianolides. A new thiophene acetylene was isolated from the aerial parts of A. schmidtiana together with some known sesquiterpene lactones. The structures were elucidated by high field 1H NMR spectroscopy.  相似文献   

13.
《Mycoscience》2014,55(3):227-230
Chlorencoelia collections from different regions of China were examined. A new species is discovered and named as C. macrospora. The most significant features to distinguish the new species from any other known species of the genus are its very large acsi and ascospores. Three of the five known species of the genus are found from China.  相似文献   

14.
《Phytochemistry》1986,25(7):1747-1749
Besides known compounds, the roots of Laserpitium garganicum subsp. garganicum afforded a new slovanolide triester. The locations of the ester moieties were assessed by correlation with a compound of known structure.  相似文献   

15.
《Phytochemistry》1986,25(4):891-897
The aerial parts of Artemisia iwayomogi afforded, in addition to already known terpenes, eleven new cudesmanolides whereas four new guaianolides were found in A. gmelinii. No sesquiterpene lactones were detected in the aerial parts of A. santolinifolia which afforded two new nerolidol derivatives besides several other already known compounds. From A. caerulescens var. cretacea six eudesmanolides were isolated, one of which has not been reported previously. The structures were elucidated by high field 1H NMR spectroscopy and chemical transformations. The chemotaxonomic significance of sesquiterpene lactones within the section Abrotanum and the subgenus Seriphidium is briefly discussed.  相似文献   

16.
From the rhizome of Iris germanica one new hexaoxygenated isoflavone, two new polyoxygenated isoflavone glucosides, the known isoflavonoids irisolidone, irigenin and iridin and acetovanillone, sitosterol, α-amyrin and β-amyrin were isolated. The structures of the new compounds were established by chemical and spectroscopic means and by correlation with known constitutents.  相似文献   

17.
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   

18.
The isolation of four known and two new germacradienolides and one known heliangolide from Helianthus pumilus, in addition to the previously report  相似文献   

19.
The aerial parts of Artemisia sieversiana afforded in addition to known compounds five new guaianolides and four dimeric guaianolides, three of them closely related to absinthin and one derived from estafiatin as a monomer. The structures were elucidated by extensive NMR studies, which allowed the assignment of the 14 chiral centres. Artemisia frigida afforded several known compounds and one new guaianolide, 8-desoxy-cumambrin B, the most likely precursor of many guaianolides.  相似文献   

20.
One new and five known compounds, which all showed cytotoxic activity, were isolated from the rhizomes of Zingiber zerumbet. The new compound was 3″,4″-O-diacetylafzelin. The known compounds were zerumbone, zerumbone epoxide, diferuloylmethane, feruloyl-p-coumaroylmethane and di-p-coumaroylmethane. Several substituted cinnamoylmethanes were synthesized and tested for cytotoxic properties. Among these were tricinnamoylmethane and triferuloylmethane. The structures were elucidated mainly by spectroscopic methods and 13C NMR data are given.  相似文献   

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