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81.
A series of camphecene and quinolizidine alkaloid (?)‐cytisine conjugates has been obtained for the first time using ‘click’ chemistry methodology. The cytotoxicity and virus‐inhibiting activity of compounds were determined against MDCK cells and influenza virus A/Puerto Rico/8/34 (H1N1), correspondingly, in in vitro tests. Based on the results obtained, values of 50 % cytotoxic dose (CC50), 50 % inhibition dose (IC50) and selectivity index (SI) were determined for each compound. It has been shown that the antiviral activity is affected by the length and nature of linkers between cytisine and camphor units. Conjugate 13 ((1R,5S)‐3‐(6‐{4‐[(2‐{(E)‐[(1R,4R)‐1,7,7‐trimethylbicyclo[2.2.1]heptan‐2‐ylidene]amino}ethoxy)methyl]‐1H‐1,2,3‐triazol‐1‐yl}hexyl)‐1,2,3,4,5,6‐hexahydro‐8H‐1,5‐methanopyrido[1,2‐a][1,5]diazocin‐8‐one), which contains cytisine fragment separated from triazole ring by –C6H12– aliphatic linker, showed the highest activity at relatively low toxicity (CC50=168 μmol, IC50=8 μmol, SI=20). Its selectivity index appeared higher than that of reference compound, rimantadine. According to theoretical calculations, the antiviral activity of the lead compound 13 can be explained by its influence on the functioning of neuraminidase.  相似文献   
82.
Scots pine (Pinus sylvestris L., Pinaceae) produces a terpenoid resin which consists of monoterpenes and resin acids that offer protection against herbivores and pathogen attacks. Methyl jasmonate (MJ) is a potential plant elicitor which induces a wide range of chemical and anatomical defence reactions in conifers and might be used to increase resistance against biotic damage. Different amounts of MJ (control, 10 mm , and 100 mm ) were applied to Scots pine to examine the vigour, physiology, herbivory performance, and induction of secondary compound production in needles, bark, and xylem of 2‐year‐old Scots pine seedlings. Growth decreased significantly in both MJ treated plants, and photosynthesis decreased in the 100 mm MJ treated plants, when compared to 10 mm MJ or control plants. The large pine weevil (Hylobius abietis L.) (Coleoptera: Curculionidae) gnawed a significantly smaller area of stem bark in the 100 mm treated plants than in the control or 10 mm treated plants. The 100 mm MJ treatment increased the resin acid concentration in the needles and xylem but not in the bark. Furthermore, both MJ treatments increased the number of resin ducts in newly developing xylem. The changes in plant growth and chemical parameters after the MJ treatments indicate shifts in carbon allocation, but MJ also affects plant physiology and xylem development. Terpenoid resin production was tissue‐specific, but generally increased after MJ treatments, which means that this compound may offer potential protection of conifers against herbivores.  相似文献   
83.
In the present work, the leaf essential oil from 97 individuals of Juniperus phoenicea var. turbinata (Guss .) Parl . from the Balkan Peninsula was analyzed. The essential oil was dominated by monoterpene hydrocarbons (45.5 – 71.8%), of which α‐pinene was the most abundant in almost all of the samples (38.2 – 55.8%). Several other monoterpenes and sesquiterpenes were also present in relatively high abundances in samples such as myrcene, δ‐3‐carene, β‐phellandrene, α‐terpinyl acetate, (E)‐caryophyllene and germacrene D. Multivariate statistical analysis suggested the existence of three possible chemotypes based on the abundance of the four components. Even though the intrapopulation variability was high, discriminant analysis (DA) was able to separate populations. DA showed high separation between western and eastern populations but also grouped geographically closer populations along the west Balkan shoreline. The potential influence of the climate on the composition of the essential oil was also studied.  相似文献   
84.
本研究旨在探究草珊瑚叶和根中萜类化合物的组织特异性分布差异,解析其药效品质差异形成的分子机制。采用液相色谱-质谱联用技术(liquid chromatography-mass spectrometry, LC-MS)和Illumina HiSeqTM高通量测序技术获得草珊瑚[Sarcandra glabra (thunb) naka]叶和根的代谢组学和转录组学数据。代谢组学结果表明参与叶和根中萜类合成的差异代谢物有50个,包括法尼西基半胱氨酸、甘油醛-3-磷酸、甲羟戊酸-5-磷酸等。转录学结果表明差异代谢酶基因有57条,包括ACTCHMGCRMVKDXSKS等,并预测了MYBC2H2AP2/ERF-ERF等7个转录因子参与调控草珊瑚不同组织部位中萜类的合成和积累差异。实时荧光定量PCR (quantitative real-time polymerase chain reaction, qRT-PCR)结果显示,随机选取的8个参与萜类合成的酶基因在草珊瑚不同组织部位中的表达趋势与转录组学测序结果一致。本研究有助于阐明草珊瑚叶和根临床疗效差异形成的分子机制,同时为草珊瑚的资源开发利用奠定基础。  相似文献   
85.
We have postulated earlier that the highly branched isoprenoid alkanes, which are distributed widely in many sediments, may have been derived from the corresponding branched polyprenyl phosphates, potentially present in biomembranes in primitive organisms. These polyprenyl-branched polyprenyl phosphates might be derived by a simple alkylation from non-substituted polyprenyl phosphates, which we postulate to be the precursors of all membrane terpenoids. We have now synthesized a series of 6-(poly)prenyl-substituted polyprenyl phosphates and studied the formation of vesicles from these phosphates, as a function of the substituted-chain length, the position of the double bond, and pH. Nine of the branched polyprenyl phosphates containing 20-30 C-atoms do form vesicles at a 'physiological' pH; the lipophilicity/hydrophilicity ratio is as expected an important factor. We have also studied the water permeability through membranes of these branched polyprenyl phosphate vesicles by our stopped-flow/light-scattering method. These highly branched polyprenyl phosphates can more effectively reduce the water permeability than non-substituted polyprenyl phosphates: the vesicles formed by the former are more stable against mechanical stress. This reinforces our hypothesis about the origin of the sedimentary polyprenyl-substituted polyprene hydrocarbons.  相似文献   
86.
BACKGROUND AND AIMS: Moss roses are old garden roses covered with a mossy growth on flower pedicel and calyx. This moss releases a pine-scented oleoresin that is very sticky and odoriferous. Rosa x centifolia 'muscosa' was the first moss rose to be obtained by bud-mutation but, interestingly, R. x damascena 'Quatre Saisons Blanc Mousseux' was the first repeat-blooming cultivar, thus interesting breeders. In the present study, the anatomy of these sports (i.e. bud-mutations) is characterized and the volatile organic compounds (VOCs) produced by the moss versus the petals are identified. They are compared between the two lines and their respective parents. METHODS: Anatomy of the moss is studied by environmental scanning electron microscopy and histochemical light microscopy. Sudan Red IV and Fluorol Yellow 088 are used to detect lipids, and 1-naphthol reaction with N,N-dimethyl-p-phenylenediamine to detect terpenes (Nadi reaction). Head-space or solid/liquid extraction followed by gas chromatography and mass spectrometry are used to identify VOCs in moss, trichomes and petals. KEY RESULTS: Moss of the two cultivars has the same structure with trichomes on other trichomes but not exactly the same VOCs. These VOCs are specific to the moss, with lots of terpenes. An identical VOC composition is found in leaves but not in petals. They are nearly the same in the moss mutants and in the respective wild types. CONCLUSIONS: Sepals of moss roses and their parents have a specific VOC pattern, different from that of the petals. The moss corresponds to a heterochronic mutation with trichomes developing on other trichomes. Such a mutation has probably appeared twice and independently in the two lines.  相似文献   
87.
In order to understand dietary differentiation among frugivorous primates with simple stomachs, we present the first comparison of plant diets between chimpanzees and cercopithecine monkeys that controls for food abundance. Our aim was to test the hypothesis that monkeys have a more diverse diet as a result of their dietary tolerance for chemical antifeedants. Our study species are chimpanzees, blue monkeys, redtail monkeys, and gray-cheeked mangabeys living in overlapping ranges in Kibale National Park, Uganda. We indexed food abundance by the percentage of trees having ripe fruit within the range of each group; it varied widely during the year. Chimpanzees spent almost 3 times as much of their feeding time eating ripe fruits as the monkeys did and confined their diets almost exclusively to ripe fruits when they were abundant. Monkeys maintained a diverse diet at all times. When ripe fruit was scarce chimpanzee and monkey diets diverged. Chimpanzees relied on piths as their main fallback food, whereas monkeys turned to unripe fruits and seeds. For each primate group we calculated the total weighted mean intake of 5 antifeedants; condensed tannins (CT), total tannins assayed by radial diffusion (RD), monoterpenoids (MT), triterpenoids (TT), and neutral-detergent fiber (NDF). Monkeys had absolutely higher intakes of CT, RD, MT, and TT than those of chimpanzees, and their intake of NDF did not differ from that of chimpanzees, appearing relatively high given their lower body weights. However contrary to expectation, dietary divergence during fruit scarcity was not associated with any change in absolute or relative intake of antifeedants. For example, fruit scarcity did not affect the relative intake of antifeedants by cercopithecines compared to chimpanzees. Our results establish chimpanzees as ripe-fruit specialists, whereas cercopithecines are generalists with a higher intake of antifeedants. The low representation of ripe fruits in the diets of cercopithecines has not been explained. An important next step is to test the hypothesis that the difference between Kibale chimpanzees and cercopithecines represents a more general difference between apes and monkeys.  相似文献   
88.
In der vorliegenden Arbeit wurde die intraplastidäre Verteilung der Chlorophylle und Carotinoide mit Hilfe der radioaktiven Doppelmarkierung untersucht. Es wurde nachgewiesen, daß für Chlorophyll a und β-Carotin zwei verschiedene Pools im Chloroplasten existieren. Chlorophyll b wie α-Carotin und die Xanthophylle sind in nur einem Pool im Chloroplasten enthalten. Die Ergebnisse zeigen außerdem, daß beide β-Carotin-Pools über zwei voneinander getrennte Biosynthesewege gebildet werden. Es wird vermutet, daß der eine β-Carotin-Pool, wie von Junge et al. (1977) nachgewiesen, im Photosystem-I enthalten ist und dort die Photooxidation des Chlorophylls verhindert. Der zweite, kleinere β-Carotin-Pool fungiert als Biosynthesepool für die Bildung der β-Ionon-Xanthophylle. Chlorophyll a ist in beiden Photosystemen kompartimentiert, während Chlorophyll b nur im Light-Harvesting-Complex und nicht in den Photosystemen enthalten sein könnte. Die Untersuchungen wurden durch eine Sachbeihilfe der Deutschen Forschungsgemeinschaft unterstützt.  相似文献   
89.
Nonpolar volatile extractives of Cupressus stephensonii heartwood amounting to 1·3% (drywood weight basis) were analyzed for their constituents and the main component was found to be carvacrol (78%). Tropolones (17%) were composed largely of β-thujaplicin and nootkatin with γ-thujaplicin in secondary quantities. Acids were low (1·7%). Neutral constituents (3·4%) contained α-pinene (8%), 4-terpinenol (27%), and methyl 4-trans-dehydrogeranate (45%).  相似文献   
90.
Summary Callus cultures derived from leaves, stem, sepals and ray flowers and cell suspension cultures of Helianthus maximiliani Schrader were established and analysed for their phytochemicals. Dark-grown cultures were found to synthesize small amounts of non-toxic, polycyclic diterpenoids when grown on modified MS-medium, while -sitosterol and palmitic acid were found in dark- and light-grown cultures. Red light irradiation did not enhance terpenoid production compared to dark- and light-grown cells.Abbreviations 2,4-D 2,4-Dichlorophenoxyacetic acid - NAA naphthaleneacetic acid - BA N-6-benzyladenine - GA gibberellic acid - TLC thin layer chromatography - GC/MS combined gas chromatography-mass specitroscopy - f wt fresh weight  相似文献   
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