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1.
Caixia Yuan Liping Lu Xiaoli Gao Yanbo Wu Maolin Guo Ying Li Xueqi Fu Miaoli Zhu 《Journal of biological inorganic chemistry》2009,14(6):841-851
Abstract A series of oxovanadium complexes with mixed ligands, a tridentate ONO-donor Schiff base ligand [viz., salicylidene anthranilic
acid (SAA)], and a bidentate NN ligand [viz., 2,2′-bipyridine (bpy), 1,10-phenanthroline (phen), dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq), dipyrido[3,2-a:2′,3′-c]phenazine (dppz), or 7-methyldipyrido[3,2-a:2′,3′-c]phenazine (dppm)], have been synthesized and characterized by elemental analysis, electrospray ionization mass spectrometry,
UV–vis spectroscopy, Fourier transform IR spectroscopy, EPR spectroscopy, and X-ray crystallography. Crystal structures of
both complexes, [VIVO(SAA)(bpy)]·0.25bpy and [VIVO(SAA)(phen)]·0.33H2O, reveal that oxovanadium(IV) is coordinated with one nitrogen and two oxygen atoms from the Schiff base and two nitrogen
atoms from the bidentate planar ligands, in a distorted octahedral geometry (VO3N3). The oxidation state of V(IV) with d
1 configuration was confirmed by EPR spectroscopy. The speciation of VO–SAA–bpy in aqueous solution was investigated by potentiomtreic
pH titrations, and the results revealed that the main species are two ternary complexes at a pH range of 7.0–7.4, and one
is the isolated crystalline complex. The complexes have been found to be potent inhibitors against human protein tyrosine
phosphatase 1B (PTP1B) (IC50 approximately 30–61 nM), T-cell protein tyrosine phosphatase (TCPTP), and Src homology phosphatase 1 (SHP-1) in vitro. Interestingly,
the [VIVO(SAA)(bpy)] complex selectively inhibits PTP1B over the other two phosphatases (approximate ninefold selectivity against
SHP-1 and about twofold selectivity against TCPTP). Kinetics assays suggest that the complexes inhibit PTP1B in a competitive
and reversible manner. These suggest that the complexes may be promising candidates as novel antidiabetic agents.
Graphical Abstract
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
2.
To investigate the structure-activity relationship of vanadium complexes in inhibiting protein tyrosine phosphatase1B (PTP1B), eight mixed-ligand oxovanadium(IV) complexes, [VIVO(SalAla)(NN)] (H2SalAla for salicylidene alanine, NN for N,N′-donor heterocyclic base, namely, 2,2′-bipyridine (bpy, 1), 1,10-phenanthroline (phen, 2), dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq, 3), dipyrido[3,2-a:2′,3′-c]phenazine (dppz, 4)), [VIVO(SalLys)(dpq)] (5), [VIVO(SalLys)(dppz)] (6), [VIVO(SalAsp)(dppz)], (7) and [VIVO(SalTrp)(dppz)] (8)), of which 3-8 are new, have been prepared and characterized by elemental analysis, infrared, UV-visible, electrospray ionization mass spectrometry and conductivity. The molar conductance data confirmed the non-electrolytic nature of the complexes in DMSO solution. The coordination in [VIVO (SalAla)(phen)] (2) was confirmed by X-ray crystal structure analysis. The oxidation state of V(IV) with d1 configuration in 2 was confirmed by EPR. The speciation of VO-SalAla-phen in aqueous solution was investigated by potentiometric pH titrations. The results indicate that the main species are two ternary complexes at the pH range 7.0-7.4. Biochemical assays demonstrate that the mixed-ligand oxovanadium(IV) complexes are potent inhibitors of PTP1B with IC50 values in the range of 62-597 nM, approximately 3-10 fold weaker in potency than those of similar mixed-ligand oxovanadium(IV) complexes of salicylidene anthranilic acid (SAA) derivative with polypyridyl ligands, except complex 8, which exhibits comparable or better inhibition activity than those of the mixed-ligand oxovanadium(IV) complexes of SAA derivative with polypyridyl ligands. The results demonstrate that the structures of vanadium complexes influence the PTP1B inhibition activity. Kinetics assays reveal that complex 2 inhibits PTP1B in a competitive manner. 相似文献
3.
Cocco MT Onnis V Ponticelli G Meier B Rehder D Garribba E Micera G 《Journal of inorganic biochemistry》2007,101(1):19-29
The complexation of VO(2+) ion by ten acetamidrazone and 2-phenylacetamidrazone derivatives (L) was studied. Sixteen novel VO(2+) complexes were synthesised and characterised through the combined application of analytical and spectroscopic (EPR (electron paramagnetic resonance), FT-IR and diffuse reflectance electronic absorption) techniques. Eight are 1:2 species of composition [VOL(2)]SO(4) x xH(2)O and eight are 1:1 species with formula [VOL(SO(4))](n) x xH(2)O. The experimental data suggest a bidentate coordination mode for L with the donor set formed by the imine nitrogen and the carbonyl oxygen. EPR spectra indicate a square-pyramidal geometry for the 1:1 complexes and a penta-coordinated geometry intermediate between the square-pyramid and the trigonal-bipyramid for the 1:2 species. The hyperfine coupling constant along z axis, A(z), of the 1:2 complexes exhibits a marked reduction with respect to the predicted value (approximately 148x10(-4)cm(-1) vs. approximately 170x10(-4)cm(-1)). IR spectroscopic evidence supports the presence of sulphate as a counter-ion in the 1:2, and as a bridging bidentate ligand in the 1:1 complexes. Insulin-mimetic tests on modified fibroblasts, based on a modified MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazoliumbromide) assay, performed on three of the bis-chelated and eight of the mono-chelated derivatives, indicate that they are biologically active. The similar hydro/lipophilicity and the lack of ligand substituents recognizable by cell membrane receptors prevent substantial differentiation in the insulin-mimetic action. 相似文献
4.
Oxovanadium(IV) complexes of the polyalcohols sorbitol, galactitol, and mannitol, of stoichiometry Na(2)[VO(L)(2)].H(2)O, were obtained from aqueous alkaline solutions. They were characterized by elemental analysis, infrared and UV-vis spectroscopies, thermoanalytical (thermogravimetric and differential thermal analysis) data, and magnetic susceptibility measurements. The biological activities of the complexes on the proliferation, differentiation, and glucose consumption were tested on osteoblast-like cells (MC3T3E1 osteoblastic mouse calvaria-derived cells and UMR106 rat osteosarcoma-derived cells) in culture. The three complexes exerted a biphasic effect on cell proliferation, being slight stimulating agents at low concentrations and inhibitory in the range of 25-100 microM. All the complexes inhibited cell differentiation in tumor osteoblasts. Their effects on glucose consumption were also discussed. The free ligands did not show any effect on the studied biological parameters. 相似文献
5.
A series of oxovanadium(IV) symmetrical tetradentate Schiff base complexes have been isolated from the reaction of VOSO4 with Schiff bases obtained from the condensation of 2-hydroxybenzophenone or 2-hydroxy-5-chlorosalicylaldehyde with various aliphatic diamines. The compounds were characterized by elemental analyses, 1H NMR, infrared, electron paramagnetic resonance, electronic spectral, cyclic voltammetry and room temperature magnetic susceptibility measurements. The solution EPR spectra are consistent with square pyramidal complexes with C4v symmetry. The IR spectra confirmed that the complexes are all monomeric except for [VO(Clsal)2tn] which polymerizes via OV?VO linkages. The electronic spectra indicate a square pyramidal geometry in both non-coordinating and coordinating solvents except for [VO(bp2-pn)] which appears to be octahedral in DMSO. The room temperature magnetic moments of 1.7-1.8 B.M. are normal for V(IV) d1 configuration. Evidence for electrochemical pseudo-reversibility is presented for four of the complexes. In vitro studies revealed that two of the compounds, [VO(bp2-en] and [VO(bp2-tn)MeOH], significantly increased glucose uptake when compared to the basal glucose uptake in transformed and sensitized C1C12 cells, but not at the same level as insulin. 相似文献
6.
Vanadate has been recognized as a specific and potent phosphatase inhibitor since its structure is similar to that of phosphate. In this study, we measured the inhibition of glutathione S-transferase-tagged protein tyrosine phosphatase 1B (GST-PTP1B) and alkaline phosphatase (ALP) by the insulin enhancing compounds, bis(maltolato)oxovanadium(IV) (BMOV). The results showed that the activity of GST-PTP1B was reversibly inhibited by solutions of BMOV with an IC50 value of 0.86 ± 0.02 μM. Steady state kinetic studies showed that inhibition of GST-PTP1B by BMOV was of a mixed competitive and noncompetitive type. In addition, incubation of GST-PTP1B with BMOV showed a time-dependent biphasic inactivation of the protein. On the other hand, the inhibitory behavior of BMOV on ALP activity was reversible and competitive with an IC50 value of 32.1 ± 0.6 μM. Incubation with BMOV did not show biphasic inactivation of ALP. The reversible inhibition of GST-PTP1B by BMOV is more potent than that of ALP, but solutions of BMOV inhibited both enzymes. This data support the suggestion that mechanisms for the inhibitory effects of BMOV on GST-PTP1B and ALP are very different. 相似文献
7.
Pragnesh K. Panchal Hitesh M. Parekh Pramod B. Pansuriya Mohan N. Patel 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):203-209
Oxovanadium(IV) complexes have been synthesized and characterized the general composition [VOL(A)], where H2L = salicylidene-o-aminothiophenol A1 = bis(benzylidene)ethylenediamine, A2 = bis(acetophenone)ethylenediamine, A3 = 2,2′-bipyridylamine, A4 = bis(benzylidene) ? 1,8-diaminonaphthalene, A5 = thiophene-o-carboxaldeneaniline and A6 = thiophene-o-carboxaldene-p-anisidine. Spectral studies indicate that the oxovanadium(IV) complexes assume a six-coordinate octahedral geometry. The antibacterial activities of the complexes against Salmonella typhi, Escherichia coli and Serratia mercescens are higher as compared to the free ligands, vanadyl sulphate, and the control (DMSO) but of moderate activity as compared to the standard drug (tetracycline). 相似文献
8.
Two novel oxovanadium(IV) complexes [VOL1]SO4 (1) and [VOL2]SO4 (2) containing Knoevenagel condensate Schiff base ligand (L1/L2) have been synthesized and characterized by physical, spectral and analytical methods. These complexes are reported as ionic in nature on the basis of elemental composition and molar conductance, and possess square pyramidal geometry around the central metal ions. The binding interactions of (1) and (2) with calf thymus DNA (CT DNA) were explored by absorption spectrophotometric titration, cyclic voltammetry data and viscosity measurements. The calculated intrinsic binding constant values (Kb) for (1) and (2) obtained from UV–Vis absorption studies are 0.4 × 105 and 5.6 × 105 (M−1) respectively. These experimental results indicate that (1) and (2) are intercalative binders and avid binder to CT DNA with different affinities. These complexes exhibit significant oxidative cleavage of supercoiled plasmid (pUC18) DNA in the presence of activators. In particular, the in vitro antimicrobial efficacy of oxovanadium(IV) complexes reveal that they are more active than free ligands. Besides, the in vitro cytotoxic effect of the titled complexes were examined on a bundle of human tumor cell lines such as MCF-7 and HeLa cancerous cell lines by the MTT method. Interestingly, complex (2) exhibits more potent cytotoxic activity than the other complex and standard drug (cisplatin). The mode of cell death was assessed by Hoechst 33258 staining morphological studies. 相似文献
9.
Oxovanadium(IV) complexes [VO(L)(B)] (1-3), where H2L is a Schiff base ligand 2-(2-hydroxybenzylideneamino)phenol and B is 1,10-phenanthroline (phen for 1), dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq for 2) or dipyrido[3,2-a:2′,3′-c]phenazine (dppz for 3), have been prepared, characterized and their DNA binding property and photo-induced DNA cleavage activity studied. Complex 3 which is structurally characterized by X-ray crystallography shows the presence of an oxovanadium(IV) moiety in a six coordinate VO3N3 coordination geometry. The complexes show a d-d band within 800-850 nm in DMF. The complexes display an oxidative response near 0.7 V versus SCE for V(V)-V(IV) and a reductive response within −1.1 to −1.3 V due to V(IV)-V(III) couple in DMF-0.1 M TBAP. The complexes are avid binders to calf thymus DNA giving binding constant values of 4.2 × 104 to 1.2 × 105 M−1. The complexes do not show any “chemical nuclease” activity in dark. The dpq and dppz complexes are photocleavers of plasmid DNA in UV-A light of 365 nm via 1O2 pathway and in near-IR light (752.5 to 799.3 nm IR optics) by HO• pathway. Complex 3 exhibits significant photocytotoxicity in visible light in HeLa cells giving IC50 value of 13 μM, while it is less toxic in dark (IC50 = 97 μM). 相似文献
10.
Ternary oxovanadium(IV) complexes [VO(salmdtc)(B)] (1-3), where salmdtc is dianionic N-salicylidene-S-methyldithiocarbazate and B is N,N-donor phenanthroline bases like 1,10-phenanthroline (phen, 1), dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq, 2) and dipyrido[3,2-a:2′,3′-c]phenazine (dppz, 3), are prepared, characterized and their DNA binding and DNA cleavage activity studied. Complex 3 is structurally characterized by single-crystal X-ray crystallography. The molecular structure shows the presence of a vanadyl group in six-coordinate VN3O2S coordination geometry. The S-methyldithiocarbazate Schiff base acts as a tridentate NSO-donor ligand in a meridional binding mode. The N,N-donor heterocyclic base displays a chelating mode of binding with an N-donor site trans to the vanadyl oxo-group. The complexes show a d-d band in the range of 675-707 nm in DMF. They exhibit an irreversible oxidative cyclic voltammetric response near 0.9 V due to the V(V)/V(IV) couple and a quasi-reversible reductive V(IV)/V(III) redox couple near −1.0 V vs. SCE in DMF-0.1 M TBAP. The complexes show good binding propensity to calf thymus DNA giving binding constant values in the range of 7.4 × 104-2.3 × 105 M−1. The thermal denaturation and viscosity binding data suggest DNA surface and/or groove binding nature of the complexes. The complexes show poor chemical nuclease activity in dark in the presence of 3-mercaptopropionic acid (MPA) or hydrogen peroxide. The dpq and dppz complexes show efficient DNA cleavage activity in UV-A light of 365 nm via a type-II mechanistic pathway involving formation of singlet oxygen (1O2) as the reactive species. 相似文献
11.
12.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):599-607
A series of biologically active oxovanadium(IV) complexes of triazole derived Schiff bases L1–L5 have been synthesized and characterized by their physical, analytical, and spectral data. The synthesized ligands potentially act as bidentate, in which the oxygen of furfural and nitrogen of azomethine coordinate with the oxovanadium atom to give a stoichiometry of vanadyl complexes 1:2 (M:L) in a square-pyramidal geometry. In vitro antibacterial and antifungal activities on different species of pathogenic bacteria (E. coli, S. flexneri, P. aeruginosa, S. typhi, S. aureus, and B. subtilis) and fungi (T. longifusus, C. albicans, A. flavus, M. canis, F. solani, and C. glabrata) have been studied. All compounds showed moderate to significant antibacterial activity against one or more bacterial strains and good antifungal activity against most of the fungal strains. The brine shrimp bioassay was also carried out to check the cytotoxicity of coordinated and uncoordinated synthesized compounds. 相似文献
13.
A series of organotin(IV) complexes with Schiff base ligand pyruvic acid 3-hydroxy-2-naphthoyl hydrazone [R2SnLY]2, L = 3-HO-C10H6-2-CONHNC(CH3)COOH, R = n-C4H9, Y = CH3OH (1), R = n-C4H9, Y = N (2), R = PhCH2 (3), R = Ph, Y = CH3OH (4), R = Me, (5) and [R3SnLY], L = 3-HO-C10H6-2-CONHNC(CH3)COOH, R = n-C4H9, Y = H2O, (6), R = Ph (7), R = Me (8) have been synthesized. These complexes have been characterized by elemental analysis, IR, 1H and 119Sn NMR spectra. The crystal and molecular structure of complexes 1, 2 and 6 have been determined by X-ray single crystal diffraction. Results showed that complex 1 has a dimeric structure and the central tin atom is rendered seven-coordinate in a distorted pentagonal-bipyramid configuration. The complex 2 has a monoclinic structure and the central tin atom is rendered six-coordinate in octahedrally configuration with a planar of SnO3N unit and two apical aryl C atoms. And the whole structure consists of molecular units connected by weak intermolecular Sn?N and O-H?N interactions. In the complex 6, the central tin atom is five-coordinate in distorted trigonal-bipyramidal geometry. 相似文献
14.
In the title family, the ONO donor ligands are the acetylhydrazones of salicylaldehyde (H2L1) and 2-hydroxyacetophenone (H2L2) (general abbreviation, H2L). The reaction of bis(acetylacetonato)oxovanadium(IV) with a mixture of tridentate H2L and a bidentate NN donor [e.g., 2,2′-bipyridine(bpy) or 1,10-phenanthroline(phen), hereafter B] ligands in equimolar ratio afforded the tetravalent complexes of the type [VIVO(L)(B)]; complexes (1)-(4) whereas, if B is replaced by 8-hydroxyquinoline(Hhq) (which is a bidentate ON donor ligand), the above reaction mixture yielded the pentavalent complexes of the type [VVO(L)(hq)]; complexes (5) and (6). Aerial oxygen is most likely the oxidant (for the oxidation of VIV → VV) in the synthesis of pentavalent complexes (5) and (6). [VIVO(L)(B)] complexes are one electron paramagnetic and display axial EPR spectra, while the [VVO(L)(hq)] complexes are diamagnetic. The X-ray structure of [VVO(L2)(hq)] (6) indicates that H2L2 ligand is bonded with the vanadium meridionally in a tridentate dinegative fashion through its phenolic-O, enolic-O and imine-N atoms. The general bond length order is: oxo < phenolato < enolato. The V-O (enolato) bond is longer than V-O (phenolato) bond by ∼0.07 Å and is identical with V-O (carboxylate) bond. 1H NMR spectrum of (6) in CDCl3 solution indicates that the binding nature in the solid state is also retained in solution. Complexes (1)-(4) display two ligand-field transitions in the visible region near 820 and 480 nm in DMF solution and exhibit irreversible oxidation peak near +0.60 V versus SCE in DMSO solution, while complexes (5) and (6) exhibit only LMCT band near 535 nm and display quasi-reversible one electron reduction peak near −0.10 V versus SCE in CH2Cl2 solution. The VO3+-VO2+E1/2 values shift considerably to more negative values when neutral NN donor is replaced by anionic ON donor species and it also provides better VO3+ binding via phenolato oxygen. For a given bidentate ligand, E1/2 increases in the order: (L2)2− < (L1)2−. 相似文献
15.
Four new caged xanthones (1–4) and two known compounds (5, 6) were isolated from the roots of Cratoxylum cochinchinense, a polyphenol rich plant, collected in China. The structures of the isolated compounds (1–6) were characterized by obtaining their detailed spectroscopic data. In particular, compounds 1 and 6 were fully identified by X-ray crystallographic data. The isolated compounds (1–6) were evaluated against protein tyrosine phosphatase 1B (PTP1B), which plays an important role in diabetes, obesity, and cancer. Among these compounds, 3, 4, and 6 displayed significant inhibition with IC50 values of 76.3, 43.2, and 6.6 µM, respectively. A detailed kinetic study was conducted by determining Km, Vmax, and the ratio of Kik and Kiv, which revealed that all the compounds behaved as competitive inhibitors. 相似文献
16.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):1199-1204
A series of 5,7-dihydroxyflavanone derivatives were synthesized and identified as reversible and competitive protein tyrosine phosphatase (PTP) 1B inhibitors with IC50 values in the micromolar range. Compound 4k had the most potent in vitro inhibition activity against PTP1B (IC50 = 2.37?±?0.37 μM) and the greatest selectivity (3.7-fold) for PTP1B relative to T-cell protein tyrosine phosphatase. Cell-based studies revealed that 4k was membrane-permeable and enhanced insulin receptor tyrosine phosphorylation in CHO/hIR cells. 相似文献
17.
Masoud Salavati-Niasari 《Inorganica chimica acta》2009,362(7):2159-2166
Oxovanadium(IV) tetraaza complexes of [14]aneN4: 1,5,8,12-tetraaza-2,9-dioxo-4,11-diphenylcyclotetradecane; [16]aneN4: 1,5,9,13-tetraaza-2,10-dioxo-4,12-diphenylcyclohexadecane; Bzo2[14]aneN4: dibenzo-1,5,8,12-tetraaza-2,9-dioxo-4,11-diphenylcyclotetradecane and Bzo2[16]aneN4: dibenzo-1,5,9,13-tetraaza-2,10-dioxo-4,12-diphenylcyclohexadecane have been encapsulated in the nanopores of zeolite-Y by a two-step process in the liquid phase: (i) adsorption of [bis(diamine)VO(IV)] (diamine = 1,2-diaminoethane, 1,3-diaminopropane, 1,2-diaminobenzene, 1,3-diaminobenzene); [VO(N-N)2]2+-NaY; in the nanopores of the zeolite-Y and (ii) in situ condensation of the oxovanadium(IV) precursor complex with ethylcinnamate. The new host-guest nanocatalysts were characterized by several techniques: chemical analysis and spectroscopic methods (FT-infrared (FT-IR), ultraviolet-visible (UV-Vis), X-ray diffraction (XRD), nitrogen adsorption and diffuse reflectance spectra (DRS)) technique. The analytical data indicated a composition corresponding to the mononuclear complex of tetraaza ligand. The characterization data showed the absence of extraneous complexes, retention of zeolite crystalline structure and encapsulation in the nanopores. Liquid-phase selective hydroxylation of phenol with H2O2 to a mixture of catechol and hydroquinone in CH3CN have been reported using oxovanadium(IV) tetraaza complexes encapsulated in zeolite-Y as catalysts. All these catalysts are more selective toward catechol formation. 相似文献
18.
Saeed Rayati Niloofar Torabi Sajjad Mohebbi Anna Kozakiewicz 《Inorganica chimica acta》2008,361(5):1239-1245
Three N2O2 tetradentate Schiff base ligands (H2L1-3) were prepared by reaction of 1,2-propylenediamine and appropriate aldehyde and ketone and characterized by FT-IR, 1H and 13C NMR. The vanadyl complexes were synthesized by treating an ethanolic solution of the appropriate ligand and one equivalent of VO(acac)2 to yield VOL1-3. These oxovanadium (IV) complexes were characterized on the basis of their FT-IR, UV-Vis spectroscopy and elemental analysis. The crystal structure of VOL3 has been determined. The metal center in VOL3 is a deformed tetragonal pyramidal N2O3 coordination sphere. These complexes are used as catalyst for the selective epoxidation of olefins. High selectivity of epoxidation for cyclooctene observed from oxidation data. The catalytic activity increases as the number of electron-donor groups increases, and the catalytic selectivity is varied by changing the substituents on the ligands. The catalytic system described here is an efficient and inexpensive method for the oxidation of olefins, with the advantages of high activity, selectivity, re-usability and short reaction time. 相似文献
19.
Basuki W Hiromura M Adachi Y Tayama K Hattori M Sakurai H 《Biochemical and biophysical research communications》2006,349(3):1163-1170
Recently, we have found that some oxovanadium(IV) complexes are potent insulin-mimetic compounds for treating both type I and type II diabetic animals. However, the functional mechanism of oxovanadium(IV) complexes is not fully understood. In this report, we have shown that oxovanadium(IV)-picolinate complexes such as VO(pa)(2), VO(3mpa)(2), and VO(6mpa)(2) act on the insulin signaling pathway in 3T3-L1 adipocytes. Among them, VO(3mpa)(2) was found to be the highest potent activator in inducing not only the phosphotyrosine levels of both IRbeta and IRS but also the activation of downstream kinases in the insulin receptor, such as Akt and GSK3beta, which in turn translocated the insulin-dependent GLUT4 to the plasma membrane. Then, we examined whether or not oxovanadium(IV)-picolinates exhibit the hypoglycemic activity in STZ-induced diabetic mice, and found that VO(3mpa)(2) is more effective than the others in improving the hyperglycemia of the animals. Our present data indicate that both activation of insulin signaling pathway, which follows the GLUT4 translocation to the plasma membrane, and enhancement of glucose utilization by oxovanadium(IV) complexes cause the hypoglycemic effect in diabetic animals. 相似文献
20.
A series of bromo-retrochalcones was designed, synthesized and evaluated as PTP1B inhibitors based on licochalcone A and E. Compounds 6, 12, 13, 14, 25, 36, 37, 39, and 41 showed potent inhibitory effects against PTP1B, and compound 37, the most potent among the series, had an IC50 value of 1.9 μM, about two-fold better than that of the positive control, ursolic acid. 相似文献