Four polyoxygenated cyclohexenes from the Chinese tree, Uvaria purpurea.
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Two novel polyoxygenated cyclohexenes, 6-methoxyzeylenol (3) and 2-acetoxyzeylenone (4), together with two known compounds, zeylenol (1) and zeylenone (2), were isolated from the heartwood of the Chinese tree, Uvaria purpurea. Zeylenol (1) and zeylenone (2) both showed inhibitory activity toward the root growth of Lactuca sativa. Their structures were established by spectroscopic and chemical methods. (+info)
Polyoxygenated cyclohexenes from the Chinese tree, Uvaria purpurea.
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Four new polyoxygenated cyclohexenes, 2-O-acetyl-6-O-methylzeylenol (2), 2-O-benzoyl-3-O-debenzoylzeylenone (5), 3-O-debenzoylzeylenone (6) and 3-O-debenzoylgrandiflorone (8), were isolated from the leaves of Uvaria purpurea. 2-O-acetyl-6-O-benzoylzeylenol (3) was also isolated for the first time as a natural product. Compounds 5-7 each showed inhibitory activity against the root growth of Lactuca sativa. Their structures were established by spectroscopic and chemical methods. (+info)
Chromone and phenanthrene alkaloids from Dennettia tripetala.
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Dennettine, a new 2,6-dimethoxychromone and three known phenanthrene alkaloids (uvariopsine, stephenanthrine and argentinine) in addition to the phenolic and known compound vanillin were isolated from the roots of Dennettia tripetala. Their structures were determined by physical and spectroscopical one dimensional (1D) and 2D-NMR analysis, including heteronuclear multiple bond correlation and nuclear Overhauser enhancement spectroscopy. (+info)
Inhibitory activities of three annonaceous acetogenins on NADH oxidase of chicken liver mitochondria.
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Annonaceous acetogenins (ACG) are natural products found in the plant family Annonaceae and which strongly inhibited mitochondrial complex I. The inhibition of NADH oxidase of chicken liver mitochondria by three different structural ACG was studied here, and ACG was shown to have potent inhibitory activities similar to rotenone for NADH oxidase. The IC(50) values indicated that bis-adjacent tetrahydrofuran (THF) type squamocin C was more potent than non-adjacent bis-THF type squamostatin B, and the latter was more potent than non-THF type compound 1 in the assay. The roles of structural factors of ACG such as the terminal gamma-lactone, the features of other ring moieties and hydroxyl groups, as well as the alkyl chain were simply discussed in this study. (+info)
Effects of ylang-ylang essential oil on the relaxation of rat bladder muscle in vitro and white rabbit bladder in vivo.
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Current and primary treatment modality in overactive bladder includes the administration of anticholinergics. The demand for new agents has been rising since anticholinergics have proven to come with many side effects. This study was designed to investigate the effects of ylang-ylang essential oil (YYEO) on the relaxation of urinary bladder muscle in vitro and in vivo. Effects of YYEO were assessed on resting tension, and electrical field stimulation- and various drug-induced contraction in vitro by checking the isometric tension changes of muscle strips and same procedures were repeated in the presence of methylene blue, Nw-Nitro-L-arginine methyl ester hydrochloride (L-NAME), or N-ethylmaleimide, and in vivo. YYEO decreased significantly the contractility of strips. There was no statistically significant difference between the treated group only with YYEO and the pretreated group with YYEO and methylene blue or L-NAME. When N-ethylmaleimide was employed, there was a statistically significant decrease in the rate of contraction. In vivo studies showed the same results compared with in vitro study. The results of this study indicate that YYEO has a relaxing effect on the bladder, and such mechanism is thought to be brought about by a pathway mediated by c-AMP. (+info)
Structural revision of epoxyrollins A and B, biosynthetic precursors of annonaceous acetogenins.
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Chemical structural elucidation of epoxyrollins A and B, representatives of biosynthetic precursors of tetrahydrofuran and tetrahydropyran annonaceous acetogenins, is described. These chemical structures were diepoxyreticanin 1 (4) and diepoxymuricanin A (6) by a (13)C-NMR and mass spectral study of the natural and synthetic sample data. (+info)
Historical biogeography of two cosmopolitan families of flowering plants: Annonaceae and Rhamnaceae.
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Annonaceae are a pantropically distributed family found predominantly in rainforests, so they are megathermal taxa, whereas Rhamnaceae are a cosmopolitan family that tend to be found in xeric regions and may be classified as mesothermal. Phylogenetic analyses of these families are presented based on rbcL and trnL-F plastid DNA sequences. Likelihood ratio tests revealed rate heterogeneity in both phylogenetic trees and they were therefore made ultrametric using non-parametric rate smoothing and penalized likelihood. Divergence times were then estimated using fossil calibration points. The historical biogeography of these families that are species rich in different biomes is discussed and compared with other published reconstructions. Rhamnaceae and most lineages within Annonaceae are too young to have had their distribution patterns influenced by break-up of previously connected Gondwanan landmasses. Contrasts in the degree of geographical structure between these two families may be explained by differences in age and dispersal capability. In both groups, long-distance dispersal appears to have played a more significant role in establishing modern patterns than had previously been assumed. Both families also contain examples of recent diversification of species-rich lineages. An understanding of the processes responsible for shaping the distribution patterns of these families has contributed to our understanding of the historical assembly of the biomes that they occupy. (+info)
Induction of leukemia cell apoptosis by cheliensisin A involves down-regulation of Bcl-2 expression.
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AIM: To investigate the apoptosis-inducing effect of cheliensisin A (GC-51), a novel styryl-lactone isolated from Goniothalamus cheliensis, on human promyelocytic leukemia HL-60 cells and the mechanism of action involved. METHODS: Apoptotic cell death was determined by morphological examination and DNA agarose gel electrophoresis. The activity of caspase-3 was assessed using Western blotting and the expression of Bcl-2 and Bax genes was analyzed using the reverse transcription-polymerase chain reaction (RT-PCR) method. RESULTS: GC-51 significantly inhibited the proliferation of HL-60 cells with an IC50 of 2.4+/-0.2 micromol/L and effectively induced apoptosis in HL-60 cells. Exposure of HL-60 cells to 10 micromol/L GC-51 for 8 h resulted in approximately 53% of the cells undergoing apoptosis. Caspase-3 was activated in GC-51-treated cells, which was manifested by the appearance of the 17 kDa active form of caspase-3 and the cleavage of poly(ADP-ribose) polymerase (PARP). Meanwhile, GC-51 markedly reduced the expression of the anti-apoptotic gene Bcl-2 and increased the expression of the pro-apoptotic gene Bax. The apoptosis-inducing effect of GC-51 was cAMP-dependent protein kinase (PKA) dependent because PKA, but not the protein kinase C, specific inhibitor H-89, blocked the induction of apoptosis by GC-51 in HL-60 cells. CONCLUSION: The results demonstrate that GC-51 effectively induces apoptosis in HL-60 cells and that this effect is PKA-dependent and involves the downregulation of Bcl-2 expression and the activation of caspase-3. (+info)