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1.
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- We compared the thermal tolerances of a high-altitude skink, Sphenomorphus taiwanensis with that of the lowland S. incognitus to test whether their thermal tolerances correspond to their altitudinal distributions. 相似文献
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- The lizard genus Plestiodon (Scincidae; formerly Eumeces) is widespread in North America and Asia, but the thermal biology of only a few species has been studied. 相似文献
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- Under natural conditions insects are occasionally subjected to thermal stresses. Data concerning the effects of these temperature extremes on tolerance and on life history parameters of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) have been lacking. 相似文献
4.
Three new copper(II) complexes of 5,5-diethlybarbiturate (barb), [Cu(barb)2(dmen)]·0.5H2O (dmen = N,N-dimethylethylenediamine) 1, [Cu(barb)2(bapa)] (bapa = bis(3-aminopropyl)amine) 2, and [Cu(barb)(apen)](barb)·2H2O (apen = N,N′-bis(3-aminopropyl)ethylenediamine) 3, have been synthesized and characterized by chemical, spectroscopic and thermal methods. Single crystal X-ray diffraction studies revealed that all complexes are mononuclear. The copper(II) ion exhibits a square-pyramidal coordination geometry in 1 and 3, but a trigonal-bipyramidal geometry in 2. The barb ligand shows different coordination modes. 1 presents the unequal coordination of the barb ligands: one is monodentate (N) and the other one is bidentate (N, O). In 2, both barb ligands are N-coordinated, whereas in 3, one barb ligand is N-coordinated, while the second barb ligand behaves as a counter-ion. The dmen, bapa and apen ligands act as bi-, tri- and tetradentate ligands, respectively. All complexes display a hydrogen-bonded network structure. The IR spectroscopic analysis shows that the ν(CO) stretching frequencies do not correlate predictably with the coordination mode of the barb ligand in 1. Thermal analysis data for 1-3 are in agreement with the crystal structures. 相似文献
5.
Aly AH Debbab A Clements C Edrada-Ebel R Orlikova B Diederich M Wray V Lin W Proksch P 《Bioorganic & medicinal chemistry》2011,19(1):414-421
Chemical investigation of the endophytic fungus Penicillium sp. isolated from Limonium tubiflorum growing in Egypt afforded four new compounds of polyketide origin, including two macrolides, penilactone (1) and 10,11-epoxycurvularin (2), a dianthrone, neobulgarone G (7), and a sulfinylcoumarin, sulfimarin (14), along with twelve known metabolites (3-6, 8-13, 15 and 16). The structures of all compounds were assigned by comprehensive spectral analysis (1D and 2D NMR) and mass spectrometry. Compounds 3, 4, 13 and 16 showed pronounced antitrypanosomal activity with mean MIC values ranging from 4.96 to 9.75 ??M. Moreover, when tested against a panel of three human tumor cell lines compounds 3, 4, 6 and 12 showed selective growth inhibition against Jurkat and U937 cell lines with IC50 values ranging from 1.8 to 13.3 ??M. The latter compounds also inhibited TNF??-induced NF-??B activity in K562 cells with IC50 values ranging from 1.6 to 10.1 ??M, respectively. 相似文献
6.
Three new compounds (3, 7, and 11) together with eight known phytoecdysteroids (1, 2, 4-6, and 8-10) were isolated from the rhizomes of common polypody, Polypodium vulgare L. The structures of compounds were elucidated by spectroscopic methods including 1D and 2D NMR measurements. The 1H and 13C NMR assignments of compounds 1, 6, 9 and 10 are included. 相似文献
7.
Aldona Beganskiene 《Inorganica chimica acta》2008,361(5):1349-1356
New t-butyl-aryl thioethers where the aryl group is 2,6-bis(phosphino)phenyl have been synthesized. The syntheses were completed via sequential ortho-lithiations of t-butylphenylsulfide, followed by chlorophosphine (ClPR2) quenches; symmetric (2,6-bis(diphenylphosphino)phenyl, (4a)) and unsymmetric (2-diisopropylphosphino-6-diphenylphosphino)phenyl, (4b) aryl groups were obtained. Treatment of 4a with Li or Na naphthalenide yielded 2,6-bis(diphenylphosphino)thiophenol 5. Reactions of 4a or 5 with NiCl2 · 6H2O yielded nickel bis(phosphinothiophenolate) 6. Compounds 4a,b, 5 and 6 were characterized by 1H and 31P NMR, and by mass-spectrometry. In addition, 4a, 5 and 6 were characterized by single crystal X-ray diffraction methods. 相似文献
8.
Anne Adsersen Ulla W. SmittHenrik T. Simonsen Søren Brøgger ChristensenJerzy W. Jaroszewski 《Biochemical Systematics and Ecology》2007
Four prenylated acetophenones 2,6-dihydroxy-4-geranyloxyacetophenone (1), 4-geranyloxy-2,6,β-trihydroxyacetophenone (2), 2,6-dihydroxy-4-geranyloxy-3-prenylacetophenone (3), and 4-geranyloxy-3-prenyl-2,6,β-trihydroxyacetophenone (4) have for the first time been isolated from Melicope obscura (1 and 2) and Melicope obtusifolia ssp. obtusifolia var. arborea (3 and 4). The distribution of prenylated acetophenones in Rutaceae is reviewed and the results, including the new records, indicate that prenylated acetophenones are valuable as chemotaxonomic markers for the subfamily Rutoideae, tribe Xanthoxyleae sensu Engler. 相似文献
9.
Bis-sesquiterpenes, henriols A (1), B (2), C (3), and D (4), and three diterpenes, henrilabdanes A (5), B (6), and C (7), together with two known bis-sesquiterpenes and three known labdane diterpenes, were isolated from the ethanol extract of the roots of Chloranthushenryi. Their structures and absolute configurations were elucidated by NMR spectroscopic, X-ray crystallographic and CD analyses. Compounds 1, 5, 6 and 7 showed moderate hepatoprotective activities with IC50 values of 0.19, 0.66, 0.09 and 0.18 μM, respectively. They were not studied further due to the weak effects noted. Compounds 3 and 8 exhibited cytotoxic activities against three types of cancer cell lines including the hepatoma (BEL-7402), human gastric carcinoma (BGC-823), and colon cancer (HCT-8). 相似文献
10.
Yanxiang Cheng 《Inorganica chimica acta》2009,362(13):4678-4684
The crystalline compounds [LnCl2(L)(thf)2] [Ln = Ce (1), Tb (2), Yb (3)], [NdI2(L)(thf)2] (4), [LnCl(L′)2] [Ln = Tb (5), Yb (6) (a known compound)] and [YbCl(L′′)(μ-Cl)2Li(OEt2)2] (7) have been prepared [L = {N(C6H3Pri2-2,6)C(H)}2CPh, L′ = {N(SiMe3)C(Ph)}2CH, L′′ = {N(SiMe3)C(C6H4Ph-4)}2CH]. The X-ray molecular structures of 2-7 have been established; in each, the monoanionic ligand L, L′ or L′′ is N,N′-chelating and essentially π-delocalised. Each of 1-7 was prepared from the appropriate LnCl3, or for 4 [NdI3(thf)2], and an equivalent portion of the appropriate alkali metal [Li for 7, Na for 2, 3 and 5, or K for 1, 4 and 6] β-diiminate in thf; the isolation of exclusively 5 and 6 (rather than the L′ analogues of 2 or 3) is noteworthy, as is the structure of 7 which has no precedent in Group 3 or 4f metal β-diiminato chemistry. 相似文献
11.
Four azaphilones, named phomoeuphorbins A-D (1-4) were isolated from cultures of Phomopsis euphorbiae, an endophytic fungus isolated from Trewia nudiflora. Structures of 1-4 were established on the basis of spectroscopic analyses, including application of 2D NMR spectroscopic techniques. Phomoeuphorbins A and C exhibited very weak inhibitory activities against HIV replication in C8166 cells in vitro. 相似文献
12.
Three new (1, 4, 9) and nine previously reported (2, 3, 5-8, 10-12) 5α,8α-epidioxysterols were isolated from the organic extracts of the gorgonian Eunicella cavolini and the ascidian Trididemnum inarmatum. The structures and relative configurations of 1-12 were established on the basis of detailed NMR spectroscopic analyses and comparison with the literature. The growth inhibitory effects of 1-12 were evaluated against MCF-7 human breast cancer cells. Compound 1, bearing a cyclopropyl moiety in the side chain, exhibited the highest antiproliferative activity. 相似文献
13.
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- Seasonal variation in thermal preference of Arctic charr from a North Norwegian population (70°N) was studied in an electronic shuttlebox, which allowed the fish to control the water temperature by moving between two chambers. The fish were acclimated to 12 °C and a natural photoperiod before measurements. Fish were tested in autumn (September–October), winter (January–February), spring (April–May) and summer (June–August). 相似文献
14.
Two copper(II) chloride complexes of amidino-O-methylurea (L1), [Cu(L1)Cl2] (1), and (N-benzyl)-amidino-O-methylurea (L2), [Cu(L2)Cl2] (2), were prepared and characterized by elemental analysis, infrared, diffuse reflectance, electron spin resonance and electrospray ionization mass spectra. Their cytosine binding abilities has been studied and found that two cytosine molecules are able to coordinate with the copper centers by replacing the chloride ligands to yield the bifunctional binding adducts [Cu(L1)(cyt)2]Cl2 (1c) and [Cu(L2)(cyt)2]Cl2 (2c), respectively. The shift of the CO band of cytosine in both cytosine-bound products to higher energy suggested that the N(3)-cytosine atom coordinates to the copper center. The large blue shifts of the d-d absorbance maxima and the nine superhyperfine splitting from the CuN4 chromophore were also observed in their electronic and EPR spectra. Their thermal decompositions have also supported the interaction of cytosine with complexes 1 and 2. Density functional calculations have also been performed and revealed that square planar coordination geometry is more stable for both 1c and 2c. The binding energy of 1c is found to be ∼20% lower than that of 2c, indicative of the higher binding potential of 1c. 相似文献
15.
The new N,N,O heteroscorpionate ligand 3,3-bis(1-vinylimidazol-2-yl)propionic acid (Hbvip) (5) was synthesised in five steps starting from 1-vinylimidazole. This ligand is closely related to 3,3-bis(1-methylimidazol-2-yl)propionic acid (Hbmip), but contains two vinyl linker groups which can be used for radical-induced polymerisation reactions. The κ3-N,N,O coordination behaviour of 5 was proven by the synthesis of the tricarbonyl complexes [Re(bvip)(CO)3] (6), [Mn(bvip)(CO)3] (7) and [Cu(bvip)2] (8). To obtain good yields of 6, it was synthesised in water instead of THF. The ligand as well as all three complexes were characterised by X-ray crystallography. Copolymerisation of 5 with pure methyl methacrylate (MMA) or a combination of MMA and ethylene glycol dimethacrylate (EGDMA) led to the solid phases P1 and P2. Polymer-bound rhenium and manganese tricarbonyl complexes could be obtained by the reaction of deprotonated P1 with [MBr(CO)5] (M = Re, Mn) and also by copolymerisation of 6 and 7 with MMA. In both cases, the facial tripodal binding behaviour was evidenced by IR spectra of the polymers. Furthermore, the content of metal incorporated in the polymers was determined by elemental analysis, AAS or ICP-OES measurements. Reaction of the deprotonated solid phase P1 with copper(II) chloride led to a blue solid-phase (P1-Cu). The UV-Vis absorption maximum of P1-Cu is found at 615 nm, which is almost identical to that found for 8. Thereby, it seems likely that P1 is flexible enough to form bisligand complexes with copper(II). This means that the copper centres act as a kind of crosslinking agents. In contrast, the heterogeneous reaction of P2 with copper(II) chloride yielded a lime green solid phase (P2-Cu). The bathochromic shift of the absorption maximum by 102 nm suggests one-sided bound copper centres. 相似文献
16.
Henk Kleijn Jeroen J.M. de Pater Anthony L. Spek Berth-Jan Deelman Gerard van Koten 《Inorganica chimica acta》2006,359(9):2674-2682
New fluorous-organometallics based on the chiral ligand α-methyl-N,N-dimethylbenzylamine (TMBA) were prepared by treatment of fluorous silyl bromide reagents with in situ 4-lithiated TMBA to give fluorous N,N-dimethyl(α-methyl-4-trialkylsilylbenzyl)amine ligands 1a-1c that vary in the number of fluorous tails attached to the Si atom. Ligands 1a-1c were successfully cyclo-palladated by treatment with Pd(OAc)2/LiCl in methanol to furnish the corresponding chloride-bridged dimeric arylpalladium(II) complexes 2a-2c in good yields. The latter derivatives could be converted into monomeric Lewis-base adducts by complexation with pyridine (3a-3c), or triphenylphosphine (4a-4c). The crystal structure of triphenylphosphine complex 4a has been elucidated. To probe their fluorophilicity, the partition coefficient of each of the derivatives in the fluorous biphasic solvent (FBS) system perfluoromethylcyclohexane/n-octane has been determined. 相似文献
17.
The essential oils and extracts of Mylia taylorii and M. nuda were investigated by gas chromatography, mass spectrometry, NMR spectroscopy and chemical correlations. Beside several known compounds 13 new constituents including three new carbon skeletons could be identified. Four hydrocarbons with a molecular formula of C15H22 (m/z 202) were identified as myli-4(15)-ene (1), aromadendra-1(10),4(15)-diene (19), aromadendra-4,10(14)-diene (20) and aromadendra-4,9-diene (21). Three oxaspiro-compounds were identified as 7-epi-bourbon-3-en-5,11-oxide (22), guai-3,10(14)-dien-5,11-oxide (23) and guai-3,9-dien-5,11-oxide (24). The absolute configuration of myli-4(15)-en-3-one (5) could be established by chemical correlation. Together with α-taylorione (7) the corresponding 6,11-seco-compound taylopyran (25) with a new carbon skeleton was identified which serves as a precursor to taylocyclane (26) and taylofuran (27). Taynudol (28) contains a new carbon skeleton with a cyclobutenyl structure. 相似文献
18.
Hu X Ji J Wang M Wu JW Zhao QS Wang HY Hou AJ 《Bioorganic & medicinal chemistry letters》2011,21(15):4441-4446
Five new isoprenylated flavonoids, notabilisins A-E (1-5), and two known Diels-Alder adducts (6 and 7), were isolated from the twigs of Morus notabilis. Compounds 4 and 5 possess two novel pyran rings, which may be biogenetically derived from 3. Compounds 1 and 3 significantly promoted adipogenesis, characterized by increased lipid droplet and triglyceride content in 3T3L1 cells, and induced up-regulation of the expression of adipocyte-specific genes, aP2 and GLUT4. 相似文献
19.
Choudhary MI Begum A Abbaskhan A Shafiq-ur-Rehman Atta-ur-Rahman 《Carbohydrate research》2006,341(14):2398-2405
Phytochemical investigation on the whole plants of Lindelofia stylosa (Kar. and Kir.) has led to the isolation of eight fructo-oligosaccharide cinnamate esters 1-8. Six new compounds 1, 2, and 5-8 were isolated from the butanol extract of the plant. Compounds 1-4 belong to sucrose derivatives, while compounds 5-6 and 7-8 belong to 1-kestose- and nystose-type oligosaccharides, respectively. The fructo-oligosaccharides have been obtained from L. stylosa for the first time. 相似文献
20.
Mairéad E. Kelly Ralph Kluge Dirk Steinborn Harry Schmidt 《Inorganica chimica acta》2009,362(4):1323-4211
A number of complexes of the types [PtBr2Me2(N?N)] (N?N = 4,4′-di-Me-2,2′-bpy (1); 4,4′-di-t-Bu-2,2′-bpy (2); 2,2′-bpz (3); bpym (4)) and [PtBr2Me2(L)2] (L = H-pz (5); 4-Me-H-pz (6); H-idz (7); H-im (8); H-bim (9); quaz (10)) are reported. Characterization by NMR (1H, 13C and 195Pt), IR and EI-MS is given. In addition, crystal structures of several of these complexes are described. Furthermore, interactions within these structures including intramolecular hydrogen bonding and π-π stacking interactions are reported. The reactivity of selected mononuclear complexes was investigated and yielded two dinuclear complexes [PPh4][(PtBrMe2)2(μ-Br)(μ-pz)2] (11) and [(PtBr2Me2)2(μ-bpym)] (12), respectively. The latter complex is accompanied by a solid-state structure. Finally, the thermal stability of all complexes is reported. 相似文献