首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Ryu HW  Cho JK  Curtis-Long MJ  Yuk HJ  Kim YS  Jung S  Kim YS  Lee BW  Park KH 《Phytochemistry》2011,72(17):2148-2154
An ethanol extract of the fruit case of Garcinia mangostan, whose most abundant chemical species are xanthones, showed potent α-glucosidase inhibitory activity (IC50 = 3.2 μg/ml). A series of isolated xanthones (1-16) demonstrated modest to high inhibition of α-glucosidase with IC50 values of 1.5-63.5 μM. In particular, one hitherto unknown xanthone 16 has a very rare 2-oxoethyl group on C-8. Kinetic enzymatic assays with a p-nitrophenyl glucopyranoside indicated that one of them, compound (9) exhibited the highest activity (Ki = 1.4 μM) and mixed inhibition. Using, a physiologically relevant substrate, maltose, as substrate, many compounds (6, 9, 14, and 15) also showed potent inhibition which ranged between 17.5 and 53.5 μM and thus compared favorably with deoxynojirimycin (IC50 = 68.8 μM). Finally, the actual pharmacological potential of the ethanol extract was demonstrated by showing that it could elicit reduction of postprandial blood glucose levels. Furthermore, the most active α-glucosidase inhibitors (6, 9, and 14) were proven to be present in high quantities in the native seedcase by a HPLC chromatogram.  相似文献   

2.
A series of novel 3,4-dihydropyrimidin-2(1H)-one urea derivatives of biological interest were prepared by sequential Bigineli’s reaction, reduction followed by reaction of resulting amines with different arylisocynates. All the synthesized (1-23) compounds were screened against the pro-inflammatory cytokines (TNF-α and IL-6) and antimicrobial activity (antibacterial and antifungal). Biological activity evaluation study reveled that among all the compounds screened, compounds 12 and 17 found to have promising anti-inflammatory activity (68-62% TNF-α and 92-86% IL-6 inhibitory activity at 10 μM). Interestingly compounds 3, 4, 5, 6, 15, 22 and 23 revealed promising antimicrobial activity at MIC of 10-30 μg/mL against selected pathogenic bacteria and fungi.  相似文献   

3.
Leaves and flowers of Artemisia gorgonum (Asteraceae) collected in Fogo, Cape Verde islands, were phytochemically investigated and resulted in isolation and characterization of three guaianolides 1, 2, 5, and a secoguainolide 4, in addition to eight known guaianolides 6-11 and two known germacranolides 12, 13. Structures were elucidated by 1D and 2D NMR experiments. Careful examination of the 13C NMR spectrum led to revision of the structure of a previously described guaianolide from 2 to 3. Most compounds exhibited mild antiplasmodial activities, ridentin (13) being the most interesting with an IC50 of 3.8 ± 0.7 μg ml−1 against Plasmodium falciparum FcB1 and weak cytotoxicity in a vero cell line (IC50 71.0 ± 3.9 μg ml−1).  相似文献   

4.
Boropinic acid is a natural isopentenyloxycinnamic acid extracted from the aerial parts of Boronia pinnata Sm. (Rutaceae) with soybean 5-lipoxygenase inhibitory activity. In this paper the topical anti-inflammatory activity of boropinic acid and some of its natural and semi-synthetic derivatives was evaluated using the Croton oil ear test in mice as a model of acute inflammation. Some of the tested compounds (15, 17, 19, 20) revealed an effect comparable (ID50 = 0.18 ÷ 0.72 μmol/cm2) to that of the reference drug indomethacin (ID50 = 0.23 μmol/cm2), a non-steroidal anti-inflammatory drug.  相似文献   

5.
The reaction of [Ti(cp)2(BTMSA)] (1) (cp = η5-C5Me5, BTMSA = bis(trimethylsilyl)acetylene) with malonic acids ((HOOC)2CR2, R = H, Me) and N,N-dimethylglycine resulted in the formation of titanium(IV) dicarboxylato complexes [Ti(cp)2{(OOC)2CR2}] (R = H, 2; R = Me, 3) and an α-amino acid titanium(III) complex [Ti(cp)2(OOCCH2NMe2)] (4). The identities of complexes 2-4 were confirmed by microanalysis, 1H and 13C NMR spectroscopy (2, 3), ESI-MS and CID experiments (2, 3) as well as by ESR and magnetic measurements (μeff = 1.81, 298 K) for 4. Single X-ray diffraction analyses of 2 and 4 exhibited monomolecular complexes in which the titanium atom is distorted tetrahedrally coordinated by two η5-C5Me5 rings and by the chelating bound malonato-κ2O,O′ (2) and N,N-dimethylglycinato-κ2O,O′ ligand (4).  相似文献   

6.
As part of an ongoing project to identify oligosaccharides which modulate bacterial multidrug resistance, the CHCl3-soluble extract from flowers of a Mexican arborescent morning glory, Ipomoea murucoides, through preparative-scale recycling HPLC, yielded five lipophilic tetrasaccharide inhibitors of Staphylococcusaureus multidrug efflux pumps, murucoidins XII-XVI (1-5). The macrocyclic lactone-type structures for these linear hetero-tetraglycoside derivatives of jalapinolic acid were established by spectroscopic methods. These compounds were tested for in vitro antibacterial and resistance modifying activity against strains of Staphylococcus aureus possessing multidrug resistance efflux mechanisms. Only murucoidin XIV (3) displayed antimicrobial activity against SA-1199B (MIC 32 μg/ml), a norfloxacin-resistant strain that over-expresses the NorA MDR efflux pump. The four microbiologically inactive (MIC > 512 μg/ml) tetrasaccharides increased norfloxacin susceptibility of this strain by 4-fold (8 μg/ml from 32 μg/ml) at concentrations of 25 μg/ml, while murucoidin XIV (3) exerted the same potentiation effect at a concentration of 5 μg/ml.  相似文献   

7.
Two new diterpenes, lobocompactols A (1) and B (2), and five known compounds (3-7) were isolated from the methanol extract of the soft coral Lobophytum compactum using combined chromatographic methods and identified based on NMR and MS data. Each compound was evaluated for cytotoxic activity against A549 (lung) and HL-60 (acute promyelocytic leukemia) human cancer cell lines. Among them, compound 5 exhibited strong cytotoxic activity against the A549 cell line with an IC50 of 4.97 ± 0.06 μM. Compounds 3, 4, and 7 showed moderate activity with IC50 values of 23.03 ± 0.76, 31.13 ± 0.08, and 36.45 ± 0.01 μM, respectively. The cytotoxicity of 5 on the A549 cells was comparable to that of the positive control, mitoxantrone (MX). All compounds exhibited moderate cytotoxicity against the HL-60 cell line, with IC50 values ranging from 17.80 ± 1.43 to 59.06 ± 2.31 μM. Their antioxidant activity was also measured using oxygen radical absorbance capacity method, compounds 1 and 2 exhibiting moderate peroxyl radical scavenging activity of 1.4 and 1.3 μM Trolox equivalents, respectively, at a concentration of 5 μM.  相似文献   

8.
[125I]IodoDPA-713 [125I]1, which targets the translocator protein (TSPO, 18 kDa), was synthesized in seven steps from methyl-4-methoxybenzoate as a tool for quantification of inflammation in preclinical models. Preliminary in vitro autoradiography and in vivo small animal imaging were performed using [125I]1 in a neurotoxicant-treated rat and in a murine model of lung inflammation, respectively. The radiochemical yield of [125I]1 was 44 ± 6% with a specific radioactivity of 51.8 GBq/μmol (1400 mCi/μmol) and >99% radiochemical purity. Preliminary studies showed that [125I]1 demonstrated increased specific binding to TSPO in a neurotoxicant-treated rat and increased radiopharmaceutical uptake in the lungs of an experimental inflammation model of lung inflammation. Compound [125I]1 is a new, convenient probe for preclinical studies of TSPO activity.  相似文献   

9.
Hyper-pigmentation of the skin is a common problem that is prevalent in middle aged and elderly people. It is caused by over production of melanin. Tyrosinase is known to be the key enzyme in melanin production. Ethanolic extract of Greyia flanaganii leaves showed significant (P < 0.05) antityrosinase activity exhibiting the IC50 of 32.62 μg/ml. The total extract was further investigated for its toxicity and effect on melanin production by melanocytes cells, and showed significant inhibition (P < 0.05) (20%) of melanin production at 6.25 μg/ml and low levels of cytotoxicity (IC50 < 400 μg/ml). The amount of antioxidants necessary to decrease the initial DPPH absorbance by 50% (EC50) by the total ethanolic extract was found to be 22.01 μg/ml. The effect of G. flanaganii against acne causing bacteria, Propionibacterium acnes, was investigated using microdilution assay. The MIC of the extract of G. flanaganii was found to be 250 μg/ml. Bioassay-guided fractionation led to the isolation of (3S)-4-hydroxyphenethyl 3-hydroxy-5-phenylpentanoate (1), 2′,4′,6′-trihydroxydihydrochalcone (2), 2′,6′,4-trihydroxy-4′-methoxydihydrochalcone (3), 2′,6′-dihydroxy-4′-methoxydihydrochalcone (4), 5,7-dihydroxyflavanone [(2S)-pinocembrin] (5), 2′,6′-dihydroxy-4′,4-dimethoxy dihydrochalcone (6) and (2R,3R)-3,5,7-trihydroxy-3-O-acetylflavanone (7). The isolated compounds were tested for their antioxidant, cytotoxicity, tyrosinase inhibition and antibacterial activities. Compound 2 exhibited significant (P < 0.05) antityrosinase activity exhibiting the IC50 of 69.15 μM. The isolated compounds showed low toxicity of the cells with reduction of melanin content of the cells. All compounds tested showed good radical scavenging activity. These data indicates that G. flanaganii extract and its isolated phenolic constituents could be possible skin lightening agents.  相似文献   

10.
(ML)2(bipy) complexes (LH2 = thiosemicarbazone of 2-hydroxybenzaldehyde, bipy = 4,4′-bipyridine, M = Ni(II), 1, or Cu(II), 2) were synthesized and characterized by X-ray crystallography. Compound 1 possessed porous structure due to peculiarities of crystal packing, whereas 2 formed infinite zig-zag chains with dense non-porous packing. It was shown that 1 absorbed 0.013 cm3/g of methanol vapor in two steps. Complex 1 was diamagnetic; for 2, the dependency of χ versus T could be interpreted by Bleaney-Bowers expression in 20-300 K temperature range (J = −6.8 cm−1, g = 2.07).  相似文献   

11.
Chemical investigation of the fungus Phellinus baumii has resulted in characterization of five previously undescribed hispidin derivatives, phellibaumins A-E (1-5), as well as two pairs of new non-equivalent epimeric benzyl dihydroflavones, methylphelligrin A (9), epi-methylphelligrin A (10), methylphelligrin B (11), and epi-methylphelligrin B (12), together with five known compounds, interfungin B (6), phelligridin H (7), phelligridimer A (8), phelligrin A (13), and epi-phelligrin A (14). Phellibaumin A (1) was a novel hispidin derivative with a unique 3,4-dihydroxybenzofuran unit. These compounds exhibited NF-κB inhibitory activity with IC50 values of 52.96 μM (1), 41.40 μM (2), 52.92 μM (5), 36.44 μM (9 and 10), and 22.46 μM (11 and 12), respectively.  相似文献   

12.
The first FeIII complexes 1-6 with cyclin-dependent kinase (CDK) inhibitors of the type [Fe(Ln)Cl3nH2O (n = 0 for 1, 1 for 2, 2 for 3-6; L1-L6 = C2- and phenyl-substituted CDK inhibitors derived from 6-benzylamino-9-isopropylpurine), have been synthesized and characterized by elemental analysis, IR, 57Fe Mössbauer, 1H and 13C NMR, and ES+ mass spectroscopies, conductivity and magnetic susceptibility measurements, and thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The study revealed that the compounds are mononuclear, tetrahedral high-spin (S = 5/2) FeIII complexes with an admixture of an S = 3/2 spin state originating probably from five-coordinated FeIII ions either connecting with a bidentate coordination mode of the CDK inhibitor ligand or relating to the possibility that one crystal water molecule enters the coordination sphere of the central atom in a portion of molecules of the appropriate complex. Nearly spin-only value of the effective magnetic moment (5.82 μeff/μB) was determined for compound 1 due to absence of crystal water molecule(s) in the structure of the complex. Based on NMR data and DFT calculations, we assume that the appropriate organic ligand is coordinated to the FeIII ion through the N7 atom of a purine moiety. The cytotoxicity of the complexes was tested in vitro against selected human cancer cell lines (G-361, HOS, K-562 and MCF-7) along with the ability to inhibit the CDK2/cyclinE kinase. The best cytotoxicity (IC50: 4-23 μM) and inhibition activity (IC50: 0.02-0.09 μM) results have been achieved in the case of complexes 2-4, and complexes 3, 4 and 6, respectively. In addition, the X-ray structure of 2-chloro-6-benzylamino-9-isopropylpurine, i.e. a precursor for the preparation of L1, L4 and L5, is also described.  相似文献   

13.
By bioactive-guided fractionation of methanol extract of the Ficus microcarpa leaves, one new C-glucosylflavone, ficuflavoside (1), one new megastigmane glycoside, ficumegasoside (8), and twelve known compounds including flavonoids (2-6), phenylpropanoids (7), megastigmanes (9-11) and sterol derivatives (12-14) were isolated. Their chemical structures were elucidated by mass, 1D, and 2D NMR spectroscopies. The antioxidant activities of these compounds were measured using the oxygen radical absorbance capacity methods. Compounds 1-6 exhibited potent antioxidant activities of 6.6-9.5 μM Trolox equivalents at the concentration of 2.0 μM. The results indicated 2, 3, and 5 having meaningful reducing capacity of copper (I) ions concentration of 6.1-8.4 μM.  相似文献   

14.
In our ongoing modification study of neo-tanshinlactone (1), we discovered 2-(furan-2-yl)naphthalen-1-ol (FNO) derivatives 3 and 4 as a new class of anti-tumor agents. To explore structure-activity relationships (SAR) of this scaffold, 18 new analogs, 6-12 and 14-24, were designed and synthesized. The C11-esters 7 and 12 displayed broad anti-tumor activity (ED50 1.1-4.3 μg/mL against seven cancer cell lines), while C11-hydroxymethyl 14 showed unique selectivity against the SKBR-3 breast cancer cell line (ED50 0.73 μg/mL). Compounds 15 and 22 displayed potent and selective anti-breast tumor activity (ED50 1.7 and 0.85 μg/mL, respectively, against MDA-MB-231). The SAR results demonstrated that the substitutions from the ring-opened lactone ring C of 1 are critical to the anti-tumor potency as well as the apparent tumor-tissue type selectivity. Treatment with 3 in Brca1f11/f11p53f5&6/f5&6Crec mice models significantly inhibited the proliferation of mammary epithelial cells and branching of mammary glands.  相似文献   

15.
Four highly oxygenated daphnane diterpenoids, trigonothyrins D-G (1-4), were isolated from the stems of Trigonostemon thyrsoideum, and their structures were elucidated on the basis of extensive spectroscopic studies. Inhibitory activity against HIV-1 was assessed for compounds 1, 3 and 4, wherein, 3 showed activity with an EC50 value of 0.13 μg/mL and a therapeutic index (TI) of 75.1.  相似文献   

16.
Three mono-nuclear copper(II) complexes [Cu(tepza)X]ClO4 (X = Cl, 1; X = NCS, 2; X = dca, 3) and two dinuclear bridging complexes [Cu2(tepza)2(μ-C4O4)](ClO4)2·H2O(4) and [Cu2(tepza)2(μ-C5O5)](ClO4)2(5) where tepza = tris[2-ethyl(1-pyrazolyl)]amine, dca = dicyanamide, C4O42− = 3,4-dihydroxycyclobut-3-ene-1,2-dionate (squarate dianion) and C5O52− = 4,5-dihydroxycyclopent-4-ene-1,2,3-trionate (croconate dianion) were synthesized and structurally characterized by IR and UV-Vis spectroscopy as well as by single X-ray crystallography. In the solid state, the geometry of copper(II) centers in these complexes are as follows: close to SP in 2, distorted TBP in 3, predominant SP in 4, and distorted octahedral in 5, whereas in solution distorted SP geometry was generally found. The squarato and the croconato dianions in complexes 4 and 5 are bridging the two copper(II) centers in cis-bis-monodentate and bis-bidentate bonding modes, respectively. Magnetic susceptibility measurements at variable temperatures (2-300 K) reveal the weak antiferromagnetic coupling in the two bridging dinuclear complexes 4 (= −24.9 cm−1) and 5 (= −3.1 cm−1).  相似文献   

17.
The structure of exo-methylene cyclopentanone, which exists in nature tetracyclic diterpenoids products, has been proved to be an innate group for the treatment of cancer and inflammation. In this letter, four different scaffolds of tetracyclic diterpenoids including the structure exo-methylene cyclopentanone were synthesized from steviol and isosteviol and evaluated in vitro for their antitumor activity against three human cancer lines. Compounds 1a, 1b, 2b and 3b showed significant cytotoxicity, particularly, tetracyclic diterpenoids 2b, 3b were identified as the most potent and selective anticancer agents superior to adriamycin with IC50 values of 0.9 μM and 1.5 μM, against Hep-G2 and MDA-MB-231 cell lines, respectively.  相似文献   

18.
Four new dinuclear Mn(III) compounds have been synthesised: [{Mn(bpy)(H2O)}2(μ-4-ClC6H4COO)2(μ-O)}](ClO4)2 (1), [{Mn(EtOH)(phen)}2(μ-O)(μ-4-ClC6H4COO)2](ClO4)2 (2), [{Mn(bpy)(EtOH)}(μ-4-BrC6H4COO)2(μ-O){Mn(bpy)(ClO4)](ClO4) (3) and [{Mn(H2O)(phen)}2(μ-4-BrC6H4COO)2(μ-O)](ClO4)2 (4). The crystal structures of 2 and 3 are evidence for the tendency of the ethanol and the perchlorate to act as ligands. Due to the coordination of these groups, the environment of the manganese ions is elongated in the monodentate ligand direction, and this distortion is more important when this ligand is the perchlorate. The magnetic properties of the four compounds have been analysed: compounds 1, 3 and 4 show antiferromagnetic behaviour, with J = −6.33 cm−1 for 1, J = −6.76 cm−1 for 3 and J = −3.08 cm−1 for 4 (H = −JS1·S2), while compound 2 shows a very weak ferromagnetic coupling. For this compound, at low temperature the most important effect on the χMT data is the zero-field splitting of the ion, and the best fit was obtained with |DMn| = 2.38 cm−1 and |EMn| = 0.22 cm−1.  相似文献   

19.
The new diiron alkynyl methoxy carbene complexes [Fe2{μ-CN(Me)(R)}(μ-CO)(CO){C(OMe)CCR′}(Cp)2]+ (R = 2,6-Me2C6H3 (Xyl), R′ = Tol, 3a; R = Xyl, R′ = Ph, 3b; R = Xyl, R′=Bun, 3c; R = Xyl, R′=SiMe3, 3d; R = Me, R′ = Tol, 3e; R = Me, R′ = Ph, 3f) are obtained in two steps by addition of R′CCLi (R′ = Tol, Ph, Bun, SiMe3) to the carbonyl aminocarbyne complexes [Fe2{μ-CN(Me)(R)}(μ-CO)(CO)2(Cp)2]+ (R = Xyl, 1a; Me, 1b), followed by methylation of the resulting alkynyl acyl compounds [Fe2{μ-CN(Me)(R)}(μ-CO)(CO){C(O)CCR′}(Cp)2] (R = Xyl, R′ = Tol, 2a; R = Xyl, R′ = Ph, 2b; R = Xyl, R′ = Bun, 2c; R = Xyl, R′ = SiMe3, 2d; R = Me, R′ = Tol, 2e; R = Me, R′ = Ph, 2f). Complexes 3 react with secondary amines (i.e., Me2NH, C5H10NH) to give the 4-amino-1-metalla-1,3-dienes [Fe2{μ-CN(Me)(R)}(μ-CO)(CO){C(OMe)CHC(R′)(NMe2)}(Cp)2]+ (R = Xyl, R′ = Tol, 4a; R = Xyl, R′ = Ph, 4b; R = Me, R′ = Ph, 4c) and [Fe2{μ-CN(Me)(Xyl)}(μ-CO)(CO){C(OMe)CHC(Tol)(NC5H10)}(Cp)2]+, 5. The addition occurs stereo-selectively affording only the E-configured products. Analogously, addition of primary amines R′NH2 (R′ = Ph, Et, Pri) affords the 4-(NH-amino)-1-metalla-1,3-diene complexes [Fe2{μ-CN(Me)(Xyl)}(μ-CO)(CO){C(OMe)CHC(R)(NHR′)}(Cp)2]+ (R = Ph, 6a; Et, 6b; Pri, 6c). In the case of 6a, only the E isomer is formed, whereas a mixture of the E and Z isomers is present in the case of 6b,c, with prevalence of the latter. Moreover, the two isomeric forms exist under dynamic equilibrium conditions, as shown by VT NMR studies. Complexes 6 are deprotonated by strong bases (e.g., NaH) resulting in the formation of the neutral vinyl imine complexes [Fe2{μ-CN(Me)(Xyl)}(μ-CO)(CO){C(OMe)CHC(NR)(Tol)}(Cp)2] (R = Ph, 7a; Et, 7b; Pri, 7c); the reaction can be reverted by addition of strong acids. X-ray crystal structures have been determined for 3a[CF3SO3] · Et2O, 4c[CF3SO3], 6a[BF4] · CH2Cl2, 6c[CF3SO3] · 0.5Et2O and 7a · CH2Cl2.  相似文献   

20.
A series of substituted benzylsulfanyl-phenylamines was synthesized, of which four substituted benzylsulfanyl-phenylguanidines (665, 666, 667 and 684) showed potent fungicidal activity (minimal fungicidal concentration, MFC ? 10 μM for Candida albicans and Candida glabrata). A benzylsulfanyl-phenyl scaffold with an unsubstituted guanidine resulted in less active compounds (MFC = 50-100 μM), whereas substitution with an unsubstituted amine group resulted in compounds without fungicidal activity. Compounds 665, 666, 667 and 684 also showed activity against single C. albicans biofilms and biofilms consisting of C. albicans and Staphylococcus epidermidis (minimal concentration resulting in 50% eradication of the biofilm, BEC50 ? 121 μM for both biofilm setups). Compounds 665 and 666 combined potent fungicidal (MFC = 5 μM) and bactericidal activity (minimal bactericidal concentration, MBC for S. epidermidis ? 4 μM). In an in vivo Caenorhabditis elegans model, compounds 665 and 667 exhibited less toxicity than 666 and 684. Moreover, addition of those compounds to Candida-infected C. elegans cultures resulted in increased survival of Candida-infected worms, demonstrating their in vivo efficacy in a mini-host model.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号