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1.
Tapirira guianensis is a common tree used in traditional medicine in French Guiana against several infectious diseases (malaria, leishmaniasis, bacteria, etc.). The bioassay-guided purification of CH2Cl2 bark extract led to the isolation of four cyclic alkyl polyol derivatives: 4,6,2′-trihydroxy-6-[10′(Z)-heptadecenyl]-1-cyclohexen-2-one (1a), 1,4,6-trihydroxy-1,2′-epoxy-6-[10′(Z)-heptadecenyl]-2-cyclohexene (1b), 1,4,5,2′-tetrahydroxy-1-[10′(Z)-heptadecenyl]-2-cyclohexene (2), and 1,3,4,6-tetrahydroxy-1,2′-epoxy-6-[10′(Z)-heptadecenyl]-cyclohexane (3). The structures were established on the basis of 1D and 2D NMR analyses. The anti-leishmanial, anti-plasmodial, anti-bacterial (on Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli), and anti-fungal (on Candida albicans) activities of the extracts and of these original compounds were evaluated. Two showed medicinal interest supporting the traditional uses of the plant. The structures were established through spectral analyses of the isolates and their derivatives.  相似文献   

2.
The aerial parts of Aruncus dioicus var. kamtschaticus afforded five new monoterpenoids (1-5): 4-(erythro-6,7-dihydroxy-9-methylpent-8-enyl)furan-2(5H)-one (1, aruncin A), 2-(8-ethoxy-8-methylpropylidene)-5-hydroxy-3,6-dihydro-2H-pyran-4-carboxylic acid (2, aruncin B), 4-(hydroxymethyl)-6-(8-methylprop-7-enyl)-5,6-dihydro-2H-pyran-2-one-11-O-β-d-glucopyranoside (3, aruncide A), (3S,4S,5R,10R)-3-(10-ethoxy-11-hydroxyethyl)-4-(5-hydroxy-7-methylbut-6-enyl)oxetan-2-one-11-O-β-d-glucopyranoside (4, aruncide B), and (3S,4S,5R,7R)-5-(9-methylprop-8-enyl)-1,6-dioxabicyclo[3,2,0]heptan-2-one-7-(hydroxymethyl)-12-O-β-d-glucopyranoside (5, aruncide C). Compound 2 showed potent cytotoxicity against Jurkat T cells with an IC50 value of 17.15 μg/mL. In addition, compounds 7 and 10 exhibited moderate antioxidant activity with IC50 values of 46.3 and 11.7 μM, respectively.  相似文献   

3.
Phytochemical analysis of Fijian populations of the green alga Tydemania expeditionis led to the isolation of two unsaturated fatty acids, 3(ζ)-hydroxy-octadeca-4(E),6(Z),15(Z)-trienoic acid (1) and 3(ζ)-hydroxy-hexadeca-4(E),6(Z)-dienoic acid (2), along with the known 3(ζ)-hydroxy-octadeca-4(E),6(Z)-dienoic acid (4). Investigations of the red alga Hydrolithon reinboldii led to identification of a glycolipid, lithonoside (3), and five known compounds, 15-tricosenoic acid, hexacosa-5,9-dienoic methyl ester, β-sitosterol, 10(S)-hydroxypheophytin A, and 10(R)-hydroxypheophytin A. The structures of 1-3 were elucidated by spectroscopic methods (1D and 2D NMR spectroscopy and ESI-MS). Compounds 1, 2, and 4, containing conjugated double bonds, demonstrated moderate inhibitory activity against a panel of tumor cell lines (including breast, colon, lung, prostate and ovarian cells) with IC50 values ranging from 1.3 to 14.4 μM. The similar cell selectivity patterns of these three compounds suggest that they might act by a common, but unknown, mechanism of action.  相似文献   

4.
Flavones and flavone glycosides from Halophila johnsonii   总被引:1,自引:0,他引:1  
Halophila johnsonii Eiseman is a shallow-water marine angiosperm which contains UV-absorbing metabolites. Studies on methanol extracts of H. johnsonii by means of HPLC-UV, NMR, HPLC-MS resulted in isolation and identification of seven previously unknown flavone glycosides: 5,6,7,3′,4′,5′-hexahydroxyflavone-7-O-β-glucopyranoside (1), 5,6,7,3′,4′,5′-hexahydroxyflavone-7-O-(6″-O-acetyl)-β-glucopyranoside (2), 6-hydroxyluteolin-7-O-(6″-O-acetyl)-β-glucopyranoside (3), 6-hydroxyapigenin-7-O-(6″-O-acetyl)-β-glucopyranoside (4), 6-hydroxyapigenin-7-O-(6″-O-[E]-coumaroyl)-β-glucopyranoside (5), 6-hydroxyapigenin-7-O-(6″-O-[E]-caffeoyl)-β-glucopyranoside (6) and 6-hydroxyluteolin-7-O-(6″-O-[E]-coumaroyl)-β-glucopyranoside (7). Also isolated were three known flavone glycosides, 6-hydroxyluteolin 7-O-β-glucopyranoside (8), scutellarein-7-O-β-glucopyranoside (9), and spicoside (10), and five known flavones, pedalitin (11), ladanetin (12), luteolin (13), apegenin (14) and myricetin (15). Qualitative comparison of the flavonoid distribution in the leaf and rhizome-root portions of the plant was also investigated, with the aim of establishing the UV-protecting roles that flavonoids played in the sea grass.  相似文献   

5.
[Ru(2,2′-bipyridine)2(Hdpa)](BF4)2 · 2H2O (1), [Ru(1,10-phenanthroline)2(Hdpa)] (PF6)2 · CH2Cl2 (2) and [Ru(4,4,4′,4′-tetramethyl-2,2′- bisoxazoline)2(Hdpa)] (PF6)2 (3) are synthesized where Hdpa is 2,2′-dipyridylamine. The X-ray crystal structures of 1 and 2 have been determined. Hdpa in 1 and 2 is found to bind the metal via the two pyridyl N ends. Comparing the NMR spectra in DMSO-d6, it is concluded that 3 has a similar structure. The pKa values (for the dissociation of the NH proton in Hdpa) of free Hdpa and its complexes are determined in acetonitrile by exploiting molar conductance. These correlate linearly with the chemical shift of the NH proton in the respective entities.  相似文献   

6.
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   

7.
Using a phosphorus based Mannich condensation reaction the new pyridylphosphines {5-Ph2PCH2N(H)}C5H3(2-Cl)N (1-Cl) and {2-Ph2PCH2N(H)}C5H3(5-Br)N (1-Br) have been synthesised in good yields (60% and 88%, respectively) from Ph2PCH2OH and the appropriate aminopyridine. The ligands 1-Cl and 1-Br display variable coordination modes depending on the choice of late transition-metal complex used. Hence P-monodentate coordination has been observed for the mononuclear complexes AuCl(1-Cl) (2), AuCl(1-Br) (3), RuCl2(p-cymene)(1-Cl) (4), RuCl2(p-cymene)(1-Br) (5), RhCl2(Cp)(1-Cl) (6), RhCl2(Cp)(1-Br) (7), IrCl2(Cp)(1-Cl) (8), IrCl2(Cp)(1′-Cl) (8′), IrCl2(Cp)(1-Br) (9), cis-/trans-PdCl2(1-Cl)2 (10), cis-/trans-PdCl2(1-Br)2 (11), cis-PtCl2(1-Cl)2 (12) and cis-PtCl2(1-Br)2 (13). Reaction of Pd(Me)Cl(cod) (cod = cycloocta-1,5-diene) with either 1 equiv. of 1-Br or the known pyridylphosphines 1′-Cl, 1-OH or 1-H gave the P/N-chelate complexes Pd(Me)Cl(1-Br-1-H) (14)-(17). All new compounds have been fully characterised by spectroscopic and analytical methods. Furthermore the structures of 4, 5, 10 and 16 · (CH3)2SO have been elucidated by single crystal X-ray crystallography. A crystal structure of the dinuclear metallocycle trans,trans-[PdCl2{μ-P/N-{Ph2PCH2N(H)}C5H4N}]2 · CHCl3, 18 · CHCl3, has also been determined. Here 1-H bridges, using both P and pyridyl N donors, two dichloropalladium centres affording a 12-membered ring with the PdCl2 units adopting a head-to-tail arrangement.  相似文献   

8.
Four analogs with 3′-O-alkyl groups (9a: CH3, 9b: C2H5, 9c: C13H27 or 9d: CH2Ph) instead of the 3′-O-sulfate anion in salacinol (1), a naturally occurring potent α-glucosidase inhibitor, were synthesized by the coupling reaction of 1,4-dideoxy-1,4-epithio-d-arabinitols (18a and 18b) with appropriate epoxides (10a-10d). These analogs showed equal or considerably higher inhibitory activity against rat small intestinal α-glucosidases than the original sulfate (1), and one of them (9d) was found more potent than currently used α-glucosidase inhibitors as antidiabetics. Thus, introduction of a hydrophobic moiety at the C3′ position of this new class of inhibitor was found beneficial for onset of stronger inhibition against these enzymes.  相似文献   

9.
Iridoid glycosides, 2′,3′,6′-tri-O-acetyl-4′-O-trans-p-(O-β-d-glucopyranosyl)coumaroyl-7-ketologanin (1), 2′-O-caffeoylloganic acid (2), 2′-O-p-hydroxybenzoylloganic acid (3), 2′-O-trans-p-coumaroylloganic acid (4), and 2′-O-cis-p-coumaroylloganic acid (5), were isolated from whole plants of Gentiana loureirii along with six known iridoids, 7-ketologanin (6), loganin (7), loganic acid (8), sweroside, boonein, and isoboonein, and three other known compounds. Their structures were elucidated by spectroscopic means and chemical correlations. The isolated iridoids were evaluated for antibacterial and antioxidant activities, but were either inactive or very weakly active.  相似文献   

10.
Three mono oxovanadium(V) complexes of tridentate Schiff base ligands [VO(OMe)L1] (1), [VO(OMe)L2] (2) and [VO(OMe)L3] (3) obtained by monocondensation of 3-hydroxy-2-naphthohydrazide and aromatic o-hydroxyaldehydes have been synthesized (H2L1 = (E)-3-hydroxy-N′-(2-hydroxy-3-methoxybenzylidene)-2-naphthohydrazide, H2L2 = (E)-3-hydroxy-N′-(2-hydroxybenzylidene)-2-naphthohydrazide and H2L3 = (E)-N′-(5-bromo-2-hydroxybenzylidene)-3-hydroxy-2-naphthohydrazide). The complexes were characterized by spectroscopic methods in the solid state (IR) and in solution (UV-Vis, 1H NMR). Single crystal X-ray analyses were performed with 1 and 2. The catalytic potential of these complexes has been tested for the oxidation of cyclooctene using H2O2 as the terminal oxidant. The effects of various parameters including the molar ratio of oxidant to substrate, the temperature, and the solvent have been studied. The catalyst 2 showed the most powerful catalytic activity in oxidation of various terminal, cyclic and phenyl substituted olefins. Excellent conversions have been obtained for the oxidation of cyclic and bicyclic olefins.  相似文献   

11.
Sterically hindered cis-carotenoids 1 and 2 were isolated from seeds of the oriental bitter sweet, Celastrus orbiculatus. Their structures were determined to be (3′Z, 5′Z)-celaxanthin and (3′Z, 5′Z)-torulene, respectively, on the basis of spectroscopic data and iodine-catalyzed stereomutation. This is the first report on carotenoids with a 3Z, 5Z configuration.  相似文献   

12.
Several new mononuclear and dinuclear ruthenium(II) complexes - incorporating 2,2′:6′,2″-terpyridine and acetylacetonate as ancillary ligands and phenylcyanamide derivative ligands - of the type [Ru(tpy)(acac)(L)] and [{Ru(tpy)(acac)}2(μ-L′)] (where tpy = 2,2′:6′,2″-terpyridine, acac = acetylacetonate, L = hmbpcyd = 4-(3-hydroxy-3-methylbutynyl)phenylcyanamide anion (2) and epcyd = 4-ethynylphenylcyanamide anion (3) and L′ = bcpda = bis(4-cyanamidophenyl)diacetylene dianion (4) and bcpea = 9,10-bis(4-cyanamidophenylethynyl)anthracene dianion (5)) were synthesized in a stepwise manner starting from [Ru(tpy)(acac)(Ipcyd)] (1), where Ipcyd = 4-iodophenylcyanamide anion. Tetraphenylarsonium salts of the phenylcyanamide derivative ligands were also prepared. The four complexes have been characterized by UV-Vis, IR, ES-MS, electrochemistry and 1H NMR. Mononuclear complexes 2 and 3 were further characterized by 13C NMR. The single crystal X-ray structure of 2 was determined, it crystallized with one molecule of water with empirical formula of C32H31N5O5Ru, in a monoclinic crystal system and space group of P21/n with a = 17.642(5) Å, b = 9.634(2) Å, c = 20.063(7) Å, β = 92.65(3)°, V = 3406(2) Å3 and Z = 4. The structure was refined to a final R factor of 0.040. The Ru(III/II) couple of 1-3 appeared around 0.34 V versus the saturated calomel electrode in dimethylformamide and at a slightly higher potential, around 0.36-0.37 V for 4 and 5. Spectroelectrochemical studies were also performed for 4 and 5, no intervalence transition was observed despite all attempts.  相似文献   

13.
Polynuclear self-assembly molecules of general formula [{Pd(en)}x(ligand)y](NO3)2x (A) undergo ligand exchange reaction when heated in DMSO. A mixture of [Pdm(ligand)n](NO3)2m (B) and [Pd(en)2](NO3)2 (C) is generated in this process. The binuclear compound (A) containing a bidentate, non-chelating ligand 1,4-bis(4′-pyridylmethyl)-2,3,5,6-tetrafluorobenzene, is subjected to ligand exchange where upon the compound (A) remains in a dynamic equilibrium with the mixture of ensuing (B) and (C). Combination of separately prepared (B) and (C) also generates (A), thus equilibrium of (A) with (B) and (C) is again observed. We predict [{Pd(bpy)}x(ligand)y](NO3)2x (A′) where 2,2′-bipyridyl (bpy) is the cis-protecting group would not probably undergo ligand exchange. The idea was conceived from the fact that (bpy) is more rigid compared to (en) moreover one of the expected products in the event of ligand exchange [Pd(bpy)2](NO3)2 (C′) is not really very stable unlike (C). In fact, when (A′) is heated in DMSO no ligand exchange is observed at all. More interestingly combination of (B) and (C′) generated (A′) smoothly. Mononuclear complexes obtained from the ligand 4-phenylpyridine are also used for similar study for comparison. It is suggested that (bpy) could serve as a better cis-protecting group for Pd(II)-based self-assembly coordination cage compounds particularly when dissolution of the assemblies in polar solvents and heating of the resultant solution is required.  相似文献   

14.
The reaction of [PdCl2(CH3CN)2] with N-alkylaminopyrazole (NN′) ligands, 1-[2-(ethylamino)ethyl]-3,5-dimethylpyrazole (deae), 1-[2-(ipropylamino)ethyl]-3,5-dimethylpyrazole (deai), and 1-[2-(tbutylamino)ethyl]-3,5-dimethylpyrazole (deat), affords a series of square planar Pd(II) complexes [PdCl2(NN′)] (NN′ = deae (1), deai (2) and deat (3)). The solid-state structures of complexes 1 and 3 were determined by single crystal X-ray diffraction studies. The NN′ ligands are coordinated through the Npz and Namine atoms to the metal atom, which completes its coordination with two chlorine atoms in a cis disposition. These palladium(II) compounds were characterised by elemental analyses, conductivity measurements, IR, 1H and 13C{1H} NMR spectroscopies. The NMR studies of the complexes prove the rigid conformation of the ligands when they are complexed.  相似文献   

15.
Chemical investigation of seven species from the brown algal genus Cystophora collected throughout Australia and New Zealand resulted in the isolation of two new compounds, 9,10-farnesylacetone epoxide (1) from Cystophora moniliformis and 1′-(2′,4′,6′-trihydroxyphenyl)-13-hydroxyoctadeca-6Z,9Z,11E,15Z-tetraen-1-one (12) from Cystophora scalaris, and 16 others that have been previously reported. Structures were elucidated using spectrometric methods, particularly 1D and 2D NMR spectroscopy. Taxonomic implications of the chemical findings are discussed including the possibility that 1 may be an intra-specific marker for the Western Australian population of C. moniliformis, and that 12 may be diagnostic for populations of C. scalaris from New Zealand waters.  相似文献   

16.
Nine (1–9) and seven (1–6, 10) compounds were isolated from the fruits of Sonneratia caseolaris and Sonneratia ovata, respectively. Their structures were identified by comparing their MS and NMR data as well as the physical properties with the literature. All the isolated compounds were screened against a rat glioma C-6 cell line using the MTT assay method; only compounds (-)-(R)-nyasol (1), (-)-(R)-4′-O-methylnyasol (2) and maslinic acid (6) were found to show moderate cytotoxic activity. Our findings from these two kinds of fruits can be used as a foundation for further chemotaxonomic studies on Sonneratia species. The nor-lignans (1, 2) and 6H-benzo[b,d]pyran-6-one derivatives (3, 4) were isolated from this genus for the first time, indicating that these two classes of compounds may tentatively be considered as taxonomic markers for Sonneratia genus.  相似文献   

17.
Five complexes [Mn2O(L1)4]n (1), [Co(L2)(H2O)2]n (2), [Co(L3)2(H2O)2]n (3) and [Co(L4)2(4,4′-bpy)(H2O)]n (4) were obtained by using flexible organic ligands HL1, HL2, HL3, and HL4 in hydrothermal systems with cobalt, copper and manganese salts respectively (HL1 = 2-(4-pyridylmethylthio)benzoic acid, HL2 = 4-(4-pyridylmethylthio)benzoic acid, HL3 = 2-(3-pyridylmethylthio)benzoic acid, HL4 = 4-(2-pyridylmethylthio)benzoic acid). The five complexes have been characterized by X-ray single crystal diffraction, FT-IR spectrum and elemental analysis. Complex 1 is assembled to a 3D porous framework with Mn2O units as nodes. Complex 2 shows 2D layer networks comprised of six-coordinated Co2+ centers and L2 anionic ions. Complexes 3 and 4 have different 1D double or single chain structures. Various non-covalent bonds such as hydrogen bonds, π?π interactions, H-bond grids and S?S weak interactions lead to interesting supramolecular frameworks. DC (direct current) temperature dependent magnetic susceptibilities suggest weak antiferromagnetic behaviors exist in 1, and single ion paramagnetic along with spin-orbit coupling behavior dominate in 3 and 4.  相似文献   

18.
Two novel Co(II) coordination polymers {[Co(H2O)2(CH3OH)2(4-bpfp)](NO3)2}n1 (4-bpfp=N,N-bis(4-pyridylformyl)piperazine) and [Co(NCS)2(CH3OH)2(3-bpfp)]n2 (3-bpfp=N,N-bis(3-pyridylformyl)piperazine) have been synthesized and characterized by single crystal X-ray diffraction. Both the polymers consist of one-dimensional chains constructed by bridging bpfp ligands and Co(II) ions. The existence of O?H-O hydrogen bond in 1 and S?H-O hydrogen bond in 2 play important roles in creating interesting supramolecular structures. Their third-order nonlinear optical (NLO) properties in DMF solution have been studied by Z-scan technique. The results reveal that polymers 1 and 2 exhibit strong NLO absorption effects (α2=9.00×10−11 m W−1 for 1; 1.41 × 10−10 m W−1 for 2) and self-focusing performance (n2=3.24×10−16 esu for 1; 3.05 × 10−16 esu for 2) in DMF solutions. The corresponding effective NLO susceptibilities χ(3) values are 3.08 × 10−12 esu (1) and 4.70 × 10−12 esu (2). All of the values are comparable to those of the reported good NLO materials. Additionally, the TG-DTA results of the two polymers are in agreement with the crystal structures.  相似文献   

19.
Six copper(I) complexes {[Cu2(L1)(PPh3)2I2] · 2CH2Cl2}n (1), {[Cu2(L2)(PPh3)2]BF4}n (2), [Cu2(L3)(PPh3)4I2] · 2CH2Cl2 (3), [Cu2(L4)(PPh3)4I2] (4), [Cu2(L5)(PPh3)2I2] (5) and [Cu2(L6)(PPh3)2I2] (6) have been prepared by reactions of bis(schiff base) ligands: pyridine-4-carbaldehyde azine (L1), 1,2-bis(4′-pyridylmethyleneamino)ethane (L2), pyridine-3-carbaldehyde azine (L3), 1,2-bis(3′-pyridylmethyleneamino)ethane (L4), pyridine-2-carbaldehyde azine (L5), 1,2-bis(2′-pyridylmethyleneamino)ethane (L6) with PPh3 and copper(I) salt, respectively. Ligand L1 or L2 links (PPh3)2Cu2(μ-I)2 units to form an infinite coordination polymer chain. Ligand 3 or 4 acts as a monodentate ligand to coordinate two copper(I) atoms yielding a dimer. Ligand 5 or 6 chelates two copper(I) atoms using pyridyl nitrogen and imine nitrogen to form a dimer. Complexes 1-4 exhibit photoluminescence in the solid state at room temperature. The emission has been attributed to be intraligand π-π* transition mixed with MLCT characters.  相似文献   

20.
Reaction of CdCl2 with N-alkylaminopyrazole ligands 1-[(2-ethylamino)ethyl]-3,5-dimethylpyrazole (deae), 1-[(2-(tert-butylamino)ethyl)]-3,5-dimethylpyrazole (deat), bis-[(3,5-dimethylpyrazolyl)methyl]ethylamine (bdmae), and bis-[(3,5-dimethylpyrazolyl)ethyl]ethylamine (ddae) in absolute ethanol yields [CdCl2(NN′)] (NN′ = deae (1), deat (2)), [CdCl2(bdmae)] (3), and [CdCl(ddae)]2[CdCl4] (4). The Cd(II) complexes have been characterised by elemental analyses, conductivity measurements, IR, 1H, 13C{1H} and 113Cd NMR spectroscopies, and X-ray diffraction methods. 1H and 113Cd NMR experiments at variable temperature for 3 and 4 show that dynamic processes are taking place in solution. We report the measurements of 113Cd NMR chemical shift data for complexes 1-4 in solution. X-ray crystal structures for complexes 2 and 3 have been determined. The Cd(II) is coordinated to the deat ligand, in 2, by one nitrogen atom of the pyrazolyl group and one nitrogen atom of the amine. It finishes a tetrahedral geometry with two chlorine atoms. The bdmae ligand is linked to Cd(II), in 3, by two nitrogens atoms of the pyrazolyl groups and one amine nitrogen, along with two chlorine atoms, in a distorted trigonal bipyramidal geometry.  相似文献   

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