Flavonoids of Agastache section Agastache

Flavonoids were characterized from the leaves, stems and inflorescences of eight species of labiates of section Agastache. Within the North American species of the section, there is a trend of reduction in number of compounds from the western to the eastern United States species. Asian Agastache rugosa has a flavonoid profile identical to that found in the western North American species.     

Flavonoids and isoflavonoids of chemotaxonomic significance from Glycyrrhiza pallidiflora (Leguminosae)

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.     

无花果亚属植物异戊烯基类黄酮及其生物活性研究进展北大核心CSCD

无花果亚属隶属于桑科,既是重要的水果资源,也是优良的中药资源,广泛种植于热带、亚热带地区,因含有丰富的生物活性成分和保健功效,经济价值突出。无花果亚属植物中异戊烯基类黄酮含量丰富,结构多样,已报道有37种异黄酮、2种黄烷酮、7种黄酮和1种查尔酮。无花果异戊烯基类黄酮具有突出的抗氧化活性,能够缓解更年期症状,保护骨骼、预防炎症、预防癌症等。从化学结构和生物活性两方面对无花果亚属植物的异戊烯基黄酮类化合物的研究概况进行总结,以期为该属植物的开发和利用提供参考。     

Chemosystematics in the Rutaceae: A chemotaxonomic survey of flavonoids and monoterpenes in leaves of Acmadenia species

By means of thin layer chromatography and gas liquid chromatography the distribution of monoterpenes and flavonoid aglycones in the leaves of 19 samples of 15 species of Acmadenia has been investigated. The distribution of flavonol and flavone aglycones shows a close agreement with recently proposed taxonomic divisions within the genus. It is proposed that these patterns may be of importance in interpreting the evolutionary development of the genus.     

Flavonoids of Helianthus series Angustifolii

Leaf and ray flower flavonoids were investigated for the seven species of Helianthus series Angustifolii. Flavone aglycones occur in small glandular trichomes located on leaf undersurfaces of H. angustifolius, H. floridanus and H. simulans. Other species lacked both glandular trichomes and flavone aglycones. Flavonol glycosides occur in low concentrations in leaves of all species but were not characterized. Anthochlors (chalkones) occur in leaves of H. heterophyllus and H. longifolius. Ray flower flavonoids include anthochlor and flavonol glycosides and occur in the basal region of the ligule producing a band of UV A around the head. Anthochlors are the predominant ray flower flavonoids in H. angustifolius, H. heterophyllus and H. longifolius, whereas they are absent and quercetin 7-glucoside is present in H. carnosus and H. floridanus. Cladistic analysis of flavonoid and morphological characters indicates that evolution in the series has been a radiation from ancestral types rather than a linear sequence of progressively more derived species.     

Flavonoids and the systematics of Luffa

Flavonoids were characterized from leaves and flowers of six species of Luffa. Each species had a distinct flavonoid pattern. Based on leaf flavonoids, Luffa is separable into two groups of species: L. graveolens and L. operculata contain only flavonols. L. acutangula, L. aergyptiaca, L. echinata and L. forskalii contain only flavones. Flavonoid data indicate that the New World disjunct species. L. operculata, is most closely related to L. graveolens.     

Pyranocoumarins as chemotaxonomic markers in Eriostemon coccineus and Philotheca citrina

Examination of the aerial parts of Eriostemon coccineus and Philotheca citrina has shown both to contain the unusual pyranocoumarins avicennol, avicennin and cis-avicennol. Three minor coumarins isolated from P. citrina have been identified as avicennol methyl ether, cis-avicennol methyl ether and avicennol ethyl ether. Philotheca citrina also yielded another pyranocoumarin, dipetalolactone, and the common lignan sesamin. Eriostemon coccineus, in addition to coumarins, gave the furoquinoline alkaloids maculosidine and γ-fagarine and two dihydrocinnanic acid derivatives, eriostoic acid and a new compound with a substitution pattern comparable to cis-avicennin and which has been assigned the trivial name cis-avicennic acid. The co-occurrence of these rare pyranocoumarins supports the contention that Philotheca is closely allied to certain taxa currently placed in Eriostemon sect. Nigrostipulae.     

Flavonoids of the primitive liverwort Takakia and their taxonomic and phylogenetic significance

The flavonoid chemistry of Takakia is described for the first time. T. lepidozioides, thought to be amongst the most primitive of extant liverworts, contains a high level and wide variety of flavone C- and O-glycosides, many of which are unique. New flavonoids include the 8-O-glucuronide and 8-O-xylosylglucoside of takakin (8-hydroxyacacetin), luteolin 6-C-arabinoside-8-C-pentoside, kaempferol 3-O-glucoside-7-O-xyloside and a number of tricetin C-glycosides. The only other known Takakia species, T. ceratophylla, contains the same 4 major constituents but significantly lacks flavonols. The often suggested relationship of Takakia with the order Calobryales is not supported by the available flavonoid data. Biochemical affinities of Takakia with all major liverwort orders are noted and the flavonoid data are interpreted as supporting the concept of Takakia as an isolated branch among the ancestors of modern bryophytes.     

Phenolic compounds of the subfamily pomoideae: A chemotaxonomic survey

The subfamily Pomoideae has been surveyed for leaf phenolics and it has been shown that flavone glycosides are present in the genera Sorbus, Aronia, Chaenomeles and Hesperomeles in addition to the previously reported occurrences in Crataegus, Malus and Pyrus. The dihydrochalcone phloridzin, a typical constituent of Malus, has also been found in Docynia. Arbutin and phenolic acid-calleryanin esters are apparently restricted to Pyrus. Naringenin and eriodictyol glucosides have been detected in Pyracantha, Sorbus, Photinia, Chaenomeles and Hesperomeles. A number of Pomoideae phenolics have been found in two Spiraeoideae genera; luteolin 7-glucoside,] luteolin 7-diglucoside, luteolin 7-rhamnosylglucoside and apigenin 7-glucoside in Exochorda and the dihydrochalcone trilobatin in Sorbaria. The chemotaxonomic evidence is consistent with the hypothesis that the Pomoideae evolved through a process of allopolyploidy from primitive members of the Spiracoideae and Prunoideae.     

Phycoerythrins as chemotaxonomic markers in red algae: A survey

A simple general procedure is described for the purification of high molecular weight phycoerythrin from red algae. Protein of purity adequate for precise spectroscopic characterization was obtained from as little as 0.2 g wet wt of fresh algal tissue. The absorption, excitation and fluorescence emission spectra of over a hundred phycoerythrins from representatives of all of the orders of the Bangiophyceae and Florideophyceae were determined. On the basis of visible absorption spectra, the phycoerythrins were subdivided into five groups: B-phycoerythrin Type I [542 > 567 > 502(s)], B-phycoerythrin Type II [566 ? 528 > 500(s)], R-phycoerythrin Type I (565 > 543 > 497), R-phycoerythrin Type II [566 > 551(s) > 496], and R-phycoerythrin Type III (567 > 539 < 496), where the numbers in parentheses specify the absorption maxima in nm and (s) denotes shoulder. Phycoerythrins do not appear to be useful at familial, ordinal and class levels in taxonomic studies. However, they do appear to be of limited value in discriminating taxonomic groupings at the generic and specific level. Audouinella (Acrochaetiales) can be separated into two groups of species, B-PE and R-PE types, but this is not correlated with cytological, morphological or life-history patterns. Rhodophysema can be removed from the Cryptonemiales and placed in the Acrochaetiales on the basis of its B-PE content, morphology and life history.     

HPLC analysis of leaf surface flavonoids for the preliminary classification of birch species

Flavonoid aglycones found on the surfaces of birch (Betula spp.) leaves may constitute up to 10% of the dry weight of the leaf. A facile extraction and HPLC procedure has been developed that can be used for the preliminary classification of birch species according to the patterns of their leaf surface flavonoids. The procedure involves no complex sample preparation steps, and is able to provide HPLC chromatograms from fresh leaves in less than 30 min. If necessary, leaves do not even need to be removed from the tree. Since the genus Betula is taxonomically complex and separation of different birch species can be problematic, the developed method was applied to 15 Betula species and four sub-species of Betula pendula Seven of the studied species were classified as B. pubescens and eight as B. pendula-type birches. The remaining four species did not belong to either of these two classes on account of their unique pattern of external flavonoids. The difference between the leaf surface flavonoid composition of B. pubescens and B. pendula type birch species was unambiguously clear, and the developed method could reliably distinguish between the two species. Whilst leaf surface flavonoids can be valuable chemotaxonomic markers, they classify birch species differently from morphological markers. Birch species with diploid chromosome sets did not contain any of the flavanones that were present in the leaves of other species. The close relationship between the occurrence of some flavonoid aglycones and the ploidy level of Betula species suggests that these chemotaxonomic markers may be useful both in taxonomic and phylogenetic analyses.     

Flavonoids from chemotypes of the goldback fern, Pityrogramma triangularis

More than 20 flavonoid aglycones were identified from the frond exudate of various collections of Pityrogramma triangularis. Ten of them are novel natural products; most of the others are rare flavonoids. They are substituted at C-8; many are C-methylated. They mostly occur only as trace constituents in var. triangularis. Two compounds come from var. viscosa. One population of P. triangularis var. triangularis exhibits a unique flavonoid pattern not encountered before in any other chemotype studied.     

红背山麻杆叶的化学成分研究(Ⅱ)——黄酮和苯乙醇苷类化合物

采用80％丙酮提取物的水萃取部位,利用凝胶、MCI、反相碳18、及 Toyopearl Butyl-650C 柱色谱进行分离纯化得到7个黄酮和3个苯乙醇苷类化合物。根据化合物的波谱数据分析鉴定为槲皮素(1)、槲皮苷(2)、异懈皮苷(3)、芦丁(4)、异牡荆素(5)、牡荆素(6)、木犀草素-7-O-α-L-鼠李糖(1→6)-β-D-葡萄糖苷(7)、2-phenethylβ-D-glucoside(8)、icariside D1(9)、2-苯乙基-D-芸香甙(10)。其中化合物1-3、5-6、8-10为首次从本属植物中分离得到。     

Flavonoids of Astilbe and Rodgersia compared to Aruncus

The flavonoid profiles of Astilbe (four taxa studied) and Rodgersia (two taxa studied) are based on simple flavonol glycosides. Astilbe has 3-O-mono-, 3-O-di-, and 3-O-triglycosides of kaempferol, quercetin, and myricetin, while Rodgersia has only mono- and diglycosides of kaempferol and quercetin. Astilbe×arendsii was also shown to accumulate dihydrochalcone glycosides. The flavonoid profile of Rodgersia is the simplest recorded so far in the herbaceous Saxifragaceae. The flavonoids of two species of Aruncus were shown to be based upon kaempferol and quercetin 3-O-mono- and 3-O-diglycosides. One of the species also exhibited an eriodictyol glycoside. The triglycoside differences were not considered important, but the differences in myricetin occurrences were taken as evidence against derivation of Saxifragaceae from an Aruncus-like ancestor. Should such an event be proposed, however, serious consideration would have to be given to the current pattern of myricetin occurrence in the two families.     

Comparative flavonoid glycoside biochemistry as a chemotaxonomic tool in the subdivision of the classical ‘genus’ Lycopodium

A wide variety of novel flavone 5-O-glucosides has been isolated from Lycopodium scariosum. The predominance of tricin derivatives in this species is not in accord with earlier proposed chemotaxonomic definitions of the sub-groups within the classical genus Lycopodium L. cernuum is the first lycopod found to contain flavone C-glycosides and its suggested taxonomic separation from other members of the group is thus substantiated. Flavonoid glycosides appear to offer more definitive chemotaxonomic characters than do the previously used aglycones and modification of the chemical definitions of the sub-groups in these terms is necessary.     

A chemotaxonomic survey of flavonoids in leaves of the Oleaceae

Leaves of 97 taxa representing all the genera at present recognized in the family Oleaceae were surveyed for flavonoids. Four flavonol glycosides were found to be common, the 3-glucmides and 3-rutinosides of quercetin and kaempferol, as were four flavone glycosides, namely the 7-glurosides arid 7-rutinosides of luteolin and apigenin. Among rarer constituents detected were luteolin 4'-glucoside, eriodictyol 7-glucoside, chrysoeriol 7-glucoside, an apigenin-di-C-glycoside and several higher glycosides of quercetin. The species and genera surveyed fell into two groups: those with flavonol glycosides alone; and those with both flavonol and flavone glycosides. The most striking correlation was with chromosome number (and subfamily division) since almost all taxa with a basic number of 11, 13 and 14 had only flavonol glycosides, whereas most taxa with x = 23 had both types of flavonoid. Evolutionary advancement in the family appears to involve the gradual replacement of flavonol by flavone glycosides. Indeed, a few tam, notably Nestegis apelala, Picconia excelsa and Tesserandra fluminense , lacked flavonol glycosides in the leaves completely. At the lower levels of classification, the distribution of flavonoids is of less interest. However, the patterns in Linociera and Chionanthus , two taxa recently made congeneric, are sufficiently different to suggest that this decision might have to be reconsidered when more is known of their chemistry. Otherwise leaf patterns generally fit in with the existing generic classification in the family.