Highly 2,3-selective polymerization of phenylallene and the derivatives by vanadium complexes

2021 ◽  
Author(s):  
Xiang Gao ◽  
Jinxin Nie ◽  
Xiaojian Chen ◽  
Li Zhou ◽  
Xiaohua Hou ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Vanadium Complexes ◽  
Vanadium Complex ◽  
Bulky Ligand

Vanadium complex containing bulky ligand were investigated for the allene polymerization. Such complexes exhibited distinguished 2,3-selectivity (>99 %) for phenylallene (PA) polymerization which were proved by the corresponding NMR spectra....

scholarly journals Carbonylniobium Chemistry, IV Derivatives of η5 -C5H5Nb(CO)4 with Tridentate Phosphines

1983 ◽  
Vol 38 (4) ◽  
pp. 446-448 ◽  
Author(s):  
Martin Hoch ◽  
Dieter Rehder
Keyword(s):  
Nmr Spectra ◽  
Membered Ring ◽  
Vanadium Complexes ◽  
Ring Complexes ◽  
Derivatives Of ◽  
Induced Reaction

Abstract The photo-induced reaction between CpNb(CO)4 and Ph2P(CH2)2PR(CH2)2PPh2 (L; R = Ph, Cy) yields the chelated five-membered ring complexes cis-[CpNb(CO)2L] (two isomers in the case of R = Cy). The uncordinated PPh2 group reacts with CpNb(CO)3THF to form CpNb(CO)2(μ-L)CpNb(CO)3. IR, 31P and 93Nb NMR spectra are discussed and compared with corresponding data of the analogous vanadium complexes.

Cell Arrest and Apoptosis Induced by the Next Generation of Vanadium Based Drugs: Action Mechanism to Structure Relation and Future Perspectives

2020 ◽  
Vol 21 ◽  
Author(s):  
Manos C. Vlasiou ◽  
Kyriaki S. Pafiti
Keyword(s):  
Anticancer Drugs ◽  
Vanadium Complexes ◽  
Ros Generation ◽  
Vanadium Complex ◽  
Next Generation ◽  
Future Perspectives ◽  
Structure Relation ◽  
Low Toxicity ◽  
Apoptotic Activity ◽  
Cell Arrest

Background: Every year we encounter more projects indicating the promising anticancer activity of vanadium molecules against different types of cancer cells. The new generation of metal-based drugs are targeting the energy supplies of the cell through ROS generation leading them to cell arrest and apoptosis. The relatively low toxicity of vanadium metal, the different oxidation states that it can be occurred and in general, the lipophilicity of transition metals, gave attention to vanadium after the exhausted research in platinumbased drugs. Herein, we are reviewing the latest advances in apoptotic activity of vanadium complex molecules and trying to reveal the structure to action relationship. Future perspectives of vanadium anticancer drugs also discussed. Methods: Data were collected from Web of Science, Scopus, Pubmed, through searching of these keywords: “apoptosis”, “anticancer drugs”, “vanadium complexes”, “synthesis” and “cell arrest”. Results: A good amount of vanadium complexes gave promising results over the last years showing that a more careful approach of a ligand design, could give a rise to the next generation of vanadium drugs. Conclusion: The low toxicity of vanadium ion in combination with its V(IV) species selectivity, gives to the vanadium, a head starts against other transition metal complexes.

Carbonylniobchemie, VII. Die 31P—NMR-Spektren der Phosphinderivate des [Nb(η5-C5H5)(CO)4] / Carbonyl Niobium Chemistry, VII. The 31P NMR Spectra of Phosphine Derivatives of [Nb(η5-C5H5)(CO)4]

1984 ◽  
Vol 39 (3) ◽  
pp. 323-332 ◽  
Author(s):  
Dieter Rehder ◽  
H.-Ch. Bechthold
Keyword(s):  
Density Matrix ◽  
Bond Order ◽  
Nmr Spectra ◽  
31P Nmr ◽  
Cone Angle ◽  
Vanadium Complexes ◽  
Nmr Data ◽  
Phosphine Derivatives ◽  
Derivatives Of ◽  
Niobium Complexes

δ(31P) NMR data of the complexes [Nb(Cp)(CO)3PZ3] (Cp = η5-C5H5) and cis- [Nb(Cp)(CO)2(PZ3)2] [Z = H, R (alkyl and aryl), OR, NMe2, PR2] are interpreted on the basis of varying P(3pσ) and P(3dπ) contributions to the bond-order density matrix in the paramagnetic deshielding term of the overall shielding constant. For Z = R, shielding of the 31P nucleus of the coordinated phosphine decreases as the cone angle θ increases, as a result of increasing p contribution. For Z = OR and NMe2, P-Nb π interactions dominate, and the decrease of the P(3dπ) occupation with increasing θ leads to an increase of shielding. In the case of alkoxiphosphines, decreasing 31P shielding is accompanied by an increase of the shielding of the metal nucleus [quantified here by δ(51V) of the vanadium complexes], while, for the substantially less powerful π interacting alkylphosphines, shielding trends for the two nuclei parallel each other. Coordination shifts Δδ(P) are somewhat greater for small phosphines but, spanning a range of 80 ± 30 ppm, tend to be comparatively invariant. In [V(Cp)(CO)3PZ3], the 31P nucleus is deshielded by 10 to 30 ppm with respect to the corresponding niobium complexes.

scholarly journals Misinterpretations in Evaluating Interactions of Vanadium Complexes with Proteins and Other Biological Targets

Inorganics ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 17
Author(s):  
João Costa Pessoa ◽  
Isabel Correia
Keyword(s):  
Biological Fluids ◽  
Aqueous Media ◽  
Binding Constants ◽  
Biological Action ◽  
Active Species ◽  
Vanadium Complexes ◽  
Vanadium Complex ◽  
Chemical Transformations ◽  
Chemical Changes ◽  
Biological Targets

In aqueous media, VIV- and VV-ions and compounds undergo chemical changes such as hydrolysis, ligand exchange and redox reactions that depend on pH and concentration of the vanadium species, and on the nature of the several components present. In particular, the behaviour of vanadium compounds in biological fluids depends on their environment and on concentration of the many potential ligands present. However, when reporting the biological action of a particular complex, often the possibility of chemical changes occurring has been neglected, and the modifications of the complex added are not taken into account. In this work, we highlight that as soon as most vanadium(IV) and vanadium(V) compounds are dissolved in a biological media, they undergo several types of chemical transformations, and these changes are particularly extensive at the low concentrations normally used in biological experiments. We also emphasize that in case of a biochemical interaction or effect, to determine binding constants or the active species and/or propose mechanisms of action, it is essential to evaluate its speciation in the media where it is acting. This is because the vanadium complex no longer exists in its initial form.

scholarly journals Cell-based Screening For Identification Of The Novel Vanadium Complexes With Multidirectional Activity Relative To The Cells And The Mechanisms Associated With Metabolic Disorders

2019 ◽  
Vol 4 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Grzegorz Kazek ◽  
Monika Głuch-Lutwin ◽  
Barbara Mordyl ◽  
Elżbieta Menaszek ◽  
Janusz Szklarzewicz ◽  
...  
Keyword(s):  
Metabolic Disorders ◽  
Glucose Utilization ◽  
Strong Support ◽  
Vanadium Complexes ◽  
Vanadium Complex ◽  
The Novel ◽  
Vanadium Compounds ◽  
Selection Of ◽  
Methyl Analog

In this study, 110 newly synthesized vanadium complexes from different structural groups were screened in three cell-based models representing the main target tissues for anti-diabetic drugs. In glucose utilization in C2C12 myocyte experiments, 93% of vanadium complexes were shown to have equal or greater activity than bis(maltolato)oxovanadium(IV) (BMOV), the methyl analog of bis(ethylmaltolato)oxovanadium(IV) (BEOV) which has been tested in clinical trials. Moreover, 49% and 50% of these complexes were shown to have equal or greater activity than BMOV in lipid accumulation in 3T3-L1 adipocytes and insulin secretion in RINm5F beta cell experiments, respectively. These results were the basis for the selection of compounds for the subsequent steps in the characterization of anti-diabetic properties. This study provides strong support for the application of screening cell-based assays with a phenotypic approach for the discovery of novel anti-diabetic drugs from the vanadium complex class. This is especially desirable due to the multiple and not fully defined mechanisms of action vanadium compounds.

scholarly journals Hypoglycemic Effect of Macrocyclic Binuclear Oxovanadium (IV) Complex on Streptozotocin-Induced Diabetic Rats

2004 ◽  
Vol 5 (2) ◽  
pp. 137-142 ◽  
Author(s):  
B. Ramachandran ◽  
D. Sathish Sekar ◽  
M. Kandaswamy ◽  
V. Narayanan ◽  
S. Subramanian
Keyword(s):  
Blood Glucose ◽  
Side Effects ◽  
Diabetic Rats ◽  
Spectral Studies ◽  
Vanadium Complexes ◽  
Vanadium Complex ◽  
Glucose Load ◽  
Oxovanadium Complex ◽  
Composition And Structure ◽  
Biochemical Studies

Though vanadium complexes mimic the action of insulin, owing to their toxicity, research is still in progress for a new vanadium complex with maximum efficacy at low concentration and without any side effects. A novel macrocyclic binuclear oxovanadium complex was synthesized, its composition and structure were confirmed by spectral studies and its efficacy was studied in streptozotocin-induced diabetic rats over a period of 30 days. The oral administration of the complex normalizes the blood glucose level in the diabetic rats and also maintains normoglycemia after a glucose load. The biochemical studies revealed that the complex is not toxic to the system. The nontoxic nature of this complex may be due to the presence of the vanadyl ions in an intact form. The study highlights the nontoxic and hypoglycemic effects of the new macrocyclic binuclear oxovanadium complex.

scholarly journals Potentiation of adipogenesis and insulinomimetic effects of novel vanadium complex (N'-[(E)-(5-bromo-2-oxophenyl)methylidene]-4-methoxybenzohydrazide)oxido(1,10-phenanthroline)vanadium(IV) in 3T3-L1 cells

2019 ◽  
Vol 4 (1) ◽  
pp. 55-62
Author(s):  
Grzegorz Kazek ◽  
Monika Głuch-Lutwin ◽  
Barbara Mordyl ◽  
Elżbieta Menaszek ◽  
Jacek Sapa ◽  
...  
Keyword(s):  
Screening Tests ◽  
Vanadium Complexes ◽  
Vanadium Complex ◽  
The Novel ◽  
Cellular Models ◽  
Proliferative Effect ◽  
Potent Inhibition ◽  
Intracellular Lipid Accumulation ◽  
Inhibition Ability

The latest results in action of vanadium compounds show important influence on adipogenesis processes and adipocytes function. Based on previously screening tests in cellular models the novel vanadium complex (N'-[(E)-(5-bromo-2-oxophenyl)methylidene]-4-methoxybenzohydrazide)oxido(1,10-phenanthroline)vanadium(IV) was selected for this study. This complex shown potent inhibition ability of tyrosine phosphatases and differences in the degree of inhibition particular phosphatases was observed. Significantly increasing of intracellular lipid accumulation and proliferative effect on 3T3-L1 preadipocytes confirmed the ability of this complex to enhancement of adipogenesis. The insulinomimetic activity of the tested complex was also demonstrated in fully differentiated 3T3-L1 adipocytes, in which glucose utilization was potentiated. Presented results support the thesis that vanadium complexes show promising possibilities for opportunities of new therapeutic strategies for the treatment of type 2 diabetes involved adipocytes.

scholarly journals Therapeutic Application of Zinc and Vanadium Complexes against Diabetes Mellitus a Coronary Disease: A review

2018 ◽  
Vol 16 (1) ◽  
pp. 1153-1165 ◽  
Author(s):  
Aisha Azam ◽  
Muhammad Asam Raza ◽  
Sajjad Hussain Sumrra
Keyword(s):  
Diabetes Mellitus ◽  
Drug Interactions ◽  
Coronary Disease ◽  
Vanadium Complexes ◽  
Vanadium Complex ◽  
Therapeutic Application ◽  
Comprehensive Discussion

AbstractDuring the last two decades, number of peoples suffering from diabetes has increased from 30-230 million globally. Today, seven out of the ten top countries are suffering from diabetes, are emergent countries. Due to alarming situations of diabetes, chemists and pharmacist are continuously searching and synthesizing new potent therapeutics to treat this disease. Now a days, considerable attention is being paid to the chemistry of the metal-drug interactions. Metals and their organic based complexes are being used clinically for various ailments. In this review, a comprehensive discussion about synthesis and diabetic evaluation of zinc and vanadium complex is summarized.

Monosubstituierte Derivate des Halbsandwich-Komplexes Cp*Ta(CO)4 - Vergleich mit den analogen Vanadiumverbindungen Cp*V(CO)3L und Röntgenstrukturanalyse des γ-Picolin-Komplexes Cp*V(CO)3(NC5H4-Me(4)) / Monosubstituted Derivatives of the Halfsandwich Complex Cp*Ta(CO)4 - Comparison with the Analogous Vanadium Compounds Cp*V(CO)3L and X-Ray Structural Analysis of the γ-Picoline Complex Cp*V(CO)3(NC5H4-Me(4))

2000 ◽  
Vol 55 (12) ◽  
pp. 1188-1194 ◽  
Author(s):  
Max Herberhold ◽  
Gudrun Frohmader ◽  
Jürgen Peukert ◽  
Wolfgang Milius
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Nmr Spectra ◽  
Crystal Structure Analysis ◽  
Cyclic Ethers ◽  
Vanadium Complex ◽  
Vanadium Compounds ◽  
X Ray ◽  
Derivatives Of ◽  
C Nmr

The photo-induced substitution of a CO ligand in Cp*Ta(CO)4 (1) has been used to prepare a series of Cp*Ta(CO)3L (2) complexes, in which the two-electron ligand L includes, e.g., isonitriles, sulfanes, cyclic ethers, phosphanes and pyridines. The complexes (2a-y) were characterized by their v(CO) frequencies and their 1H and 13C NMR spectra, and were compared - if possible - with the corresponding vanadium complex, Cp*V(CO)4 (3) and its derivatives, Cp*V(CO)3L (4). The molecular structure of the 4-picoline complex Cp*V(CO)3(NC5H4-Me(4)) (4r) has been determined by X-ray crystal structure analysis.

Sign in / Sign up

Export Citation Format

Share Document