The Experts below are selected from a list of 258 Experts worldwide ranked by ideXlab platform
Sheo K. Dikshit - One of the best experts on this subject based on the ideXlab platform.
-
Synthesis and Characterization of Mixed- Ligand Complexes of Cu(I) Containing Halides, Triphenylstibine and Triphenylbismuthine, N,N-Dimethyl-N′-Phenylthiourea (Dmpth), N,N-Dibutyl-N′-Phenylthiourea (dbptH) and 1,3-thiazolidine-2-thione (tzdtH)
Synthesis and Reactivity in Inorganic and Metal-Organic Chemistry, 2000Co-Authors: Sudhir Ranjan, Sheo K. DikshitAbstract:Abstract The triphenylstibine and bismuthine complexes [Cu(EPh3)(LH)2X] (LH = N, N-dimethyl-N′-Phenylthiourea) (dmptH), N, N-dibutyl-N′-Phenylthiourea (dbptH) or 1, 3-thiazolidine-2-thione (tzdtH); E = Sb or Bi; X = Cl, Br or I have been prepared and characterized on the basis of analytical, IR. electronic (UV-Vis), 1H and I3C NMR, FAB mass and conductivity measurements. In all cases there is a distorted tetrahedral environment around Cu(I) and the ligand (LH) binds through the thionc sulphur atom to copper(1). This is confirmed by FTIR spectra of the complexes. The complexes show v(Cu-Sb) in the range 180–195 cm−1.
-
synthesis and characterization of mixed ligand copper i complexes containing halides triphenylarsine and n n dimethyl n Phenylthiourea dmpth n n dibutyl n Phenylthiourea dbpth or 1 3 thiazolidine 2 thione tzdth the x ray crystal structure of cu pph3
Polyhedron, 1995Co-Authors: Ramsharan Singh, Sheo K. DikshitAbstract:Abstract The arsine complexes [Cu(AsPh3)2(LH)X] (LH = N,N-dimethyl-N′-Phenylthiourea (dmptH), N,N-dibutyl-N′-Phenylthiourea (dbptH) or 1,3-thiazolidine-2-thione (tzdtH); X = Cl, Br, I) have been prepared and characterized on the basis of analytical, IR, electronic (UV-vis), 1H NMR, conductivity and magnetic measurements. In all cases there is a distorted tetrahedral environment around copper(I) and the ligands (LH) bind through thione sulphur atom to copper(I). We also report the crystal structure of complex [Cu(PPh3)2(dmptH)Cl] which shows that metal ion has a distorted tetrahedral geometry with bond lengths CuS = 2.459(2), CuCl = 2.308(1), CuP(1) = 2.305(1) and Cu P (2) = 2.313(1) A . The NH is intramolecularly hydrogen bonded to Cl with a bond distance NH … Cl = 2.31 A
-
Synthesis and characterization of mixed ligand copper(I) complexes containing halides, triphenylarsine and N,N-dimethyl-N′-Phenylthiourea (dmptH), N,N-dibutyl-N′-Phenylthiourea (dbptH) or 1,3-thiazolidine-2-thione (tzdtH). The X-ray crystal structure
Polyhedron, 1995Co-Authors: Ramsharan Singh, Sheo K. DikshitAbstract:Abstract The arsine complexes [Cu(AsPh3)2(LH)X] (LH = N,N-dimethyl-N′-Phenylthiourea (dmptH), N,N-dibutyl-N′-Phenylthiourea (dbptH) or 1,3-thiazolidine-2-thione (tzdtH); X = Cl, Br, I) have been prepared and characterized on the basis of analytical, IR, electronic (UV-vis), 1H NMR, conductivity and magnetic measurements. In all cases there is a distorted tetrahedral environment around copper(I) and the ligands (LH) bind through thione sulphur atom to copper(I). We also report the crystal structure of complex [Cu(PPh3)2(dmptH)Cl] which shows that metal ion has a distorted tetrahedral geometry with bond lengths CuS = 2.459(2), CuCl = 2.308(1), CuP(1) = 2.305(1) and Cu P (2) = 2.313(1) A . The NH is intramolecularly hydrogen bonded to Cl with a bond distance NH … Cl = 2.31 A
İlhami Gülçin - One of the best experts on this subject based on the ideXlab platform.
-
Synthesis, characterization, antioxidant, antidiabetic, anticholinergic, and antiepileptic properties of novel N-substituted tetrahydropyrimidines based on Phenylthiourea.
Journal of biochemical and molecular toxicology, 2018Co-Authors: Gunel Maharramova, Parham Taslimi, Afsun Sujayev, Vagif Farzaliyev, Lokman Durmaz, İlhami GülçinAbstract:In the presence of trifluoroacetic acid, on the basis of three-component condensation of Phenylthiourea with its salicylaldehyde and methyl-3-oxobutanoate, an efficient method for the synthesis of 1-(4-(2-hydroxyphenyl)-6-methyl-1-phenyl-2-thioxo-1,2,3,4-tetrahydropyrimidin-5-yl)ethanone (I) has been worked out. These novel N-substituted tetrahydropyrimidines based on Phenylthiourea showed good inhibitory action against acetylcholinesterase (AChE), α-glycosidase, and human carbonic anhydrase (hCA) isoforms I and II. K i values of AChE enzyme were in the range of 0.48 to 7.46 nM. The hCA I and II were effectively inhibited by the compounds, with K i values in the range of 502.44 to 923.11 nM for hCA I and 400.32 to 801.57 nM for hCA II, respectively. The antioxidant activity of the novel N-substituted tetrahydropyrimidines based on Phenylthiourea was investigated by using different in vitro antioxidant assays; including 1,1-diphenyl-2-picrylhydrazyl (DPPH·) radical scavenging, Cu 2+ and Fe 3+ reducing activities.
Wim J Quax - One of the best experts on this subject based on the ideXlab platform.
-
development of Phenylthiourea derivatives as allosteric inhibitors of pyoverdine maturation enzyme pvdp tyrosinase
Bioorganic & Medicinal Chemistry Letters, 2020Co-Authors: Joko Priyanto Wibowo, Frank J Dekker, Zhangping Xiao, Julian M Voet, Wim J QuaxAbstract:Infections caused by Pseudomonas aeruginosa become increasingly difficult to treat because these bacteria have acquired various mechanisms for antibiotic resistance, which creates the need for mechanistically novel antibiotics. Such antibiotics might be developed by targeting enzymes involved in the iron uptake mechanism because iron is essential for bacterial survival. For P. aeruginosa, pyoverdine has been described as an important virulence factor that plays a key role in iron uptake. Therefore, inhibition of enzymes involved in the pyoverdine synthesis, such as PvdP tyrosinase, can open a new window for the treatment of P. aeruginosa infections. Previously, we reported Phenylthiourea as the first allosteric inhibitor of PvdP tyrosinase with high micromolar potency. In this report, we explored structure-activity relationships (SAR) for PvdP tyrosinase inhibition by Phenylthiourea derivatives. This enables identification of a Phenylthiourea derivative (3c) with a potency in the submicromolar range (IC50 = 0.57 + 0.05 µM). Binding could be rationalized by molecular docking simulation and 3c was proved to inhibit the bacterial pyoverdine production and bacterial growth in P. aeruginosa PA01 cultures.
-
a novel mechanism of inhibition by Phenylthiourea on pvdp a tyrosinase synthesizing pyoverdine of pseudomonas aeruginosa
International Journal of Biological Macromolecules, 2020Co-Authors: Joko Priyanto Wibowo, Fernando De Assis Batista, Niels Van Oosterwijk, Matthew R Groves, Frank J Dekker, Wim J QuaxAbstract:The biosynthesis of pyoverdine, the major siderophore of Pseudomonas aeruginosa, is a well-organized process involving a discrete number of enzyme-catalyzed steps. The final step of this process involves the PvdP tyrosinase, which converts ferribactin into pyoverdine. Thus, inhibition of the PvdP tyrosinase activity provides an attractive strategy to interfere with siderophore synthesis to manage P. aeruginosa infections. Here, we report Phenylthiourea as a non-competitive inhibitor of PvdP for which we solved a crystal structure in complex with PvdP. The crystal structure indicates that Phenylthiourea binds to an allosteric binding site and thereby interferes with its tyrosinase activity. We further provide proofs that PvdP tyrosinase inhibition by Phenylthiourea requires the C-terminal lid region. This provides opportunities to develop inhibitors that target the allosteric site, which seems to be confined to fluorescent pseudomonads, and not the tyrosinase active site. Furthermore, increases the chances to identify PvdP inhibitors that selectively interfere with siderophore synthesis.
Ahmady A. Yassin - One of the best experts on this subject based on the ideXlab platform.
-
Organic thermal stabilizers for rigid poly(vinyl chloride). VIII. Phenylurea and Phenylthiourea derivatives
Polymer Degradation and Stability, 2003Co-Authors: Magdy W. Sabaa, Riham R. Mohamed, Ahmady A. YassinAbstract:Abstract Phenylurea and Phenylthiourea derivatives have been investigated as thermal stabilizers or co-stabilizers for rigid PVC in air, at 180 °C. The results reveal the higher stabilizing potency of the investigated organic stabilizers as compared with commercial reference stabilizers, which is proved by their greater induction period values, but with higher dehydrochlorination rate at the later stages of degradation. Complexation of these materials with the chlorides of Ni 2+ and Cd 2+ greatly improved the induction period values, however the dehydrochlorination rate is only slightly improved. On the other hand, blending the investigated thermal stabilizers with some of the commercially known reference stabilizers in different proportions leads to a true synergistic effect. The induction period values and the degradation rate were remarkably improved. A probable mechanism for the stabilizing action of phenylurea and Phenylthiourea derivatives has been proposed.
-
organic thermal stabilizers for rigid poly vinyl chloride part x n acryloyl n p substituted Phenylthiourea derivatives
Polymer Degradation and Stability, 2003Co-Authors: Magdy W. Sabaa, Riham R. Mohamed, Ahmady A. YassinAbstract:Abstract N-Benzoyl-N′-p-substituted Phenylthiourea derivatives have been investigated as thermal stabilizers or co-stabilizers for rigid PVC at 180 °C in air. The results reveal the higher stabilizing potency of the investigated organic stabilizers as compared with some of the commercially known reference stabilizers, which is proved by their greater induction period values (Ts), during which no detectable amount of hydrogen chloride gas could be detected, but with higher dehydrochlorination rate at the later stages of degradation. Complexation of these materials with the chlorides of Ni2+ and Cd2+ improved greatly the induction period values, however the dehydrochlorination rate is only slightly improved. On the other hand, blending these thermal stabilizers with some of the commercially known reference stabilizers in different proportions leads to a true synergistic effect. The induction period values and the degradation rate were remarkably improved. A probable ionic mechanism for the stabilizing action of N-Benzoyl-N′-p-substituted Phenylthiourea derivatives is proposed. The stabilizing efficiency is attributed to the replacement of the labile chloride ions on the PVC chains by a relatively more stable moiety of the stabilizer.
Ramsharan Singh - One of the best experts on this subject based on the ideXlab platform.
-
synthesis and characterization of mixed ligand copper i complexes containing halides triphenylarsine and n n dimethyl n Phenylthiourea dmpth n n dibutyl n Phenylthiourea dbpth or 1 3 thiazolidine 2 thione tzdth the x ray crystal structure of cu pph3
Polyhedron, 1995Co-Authors: Ramsharan Singh, Sheo K. DikshitAbstract:Abstract The arsine complexes [Cu(AsPh3)2(LH)X] (LH = N,N-dimethyl-N′-Phenylthiourea (dmptH), N,N-dibutyl-N′-Phenylthiourea (dbptH) or 1,3-thiazolidine-2-thione (tzdtH); X = Cl, Br, I) have been prepared and characterized on the basis of analytical, IR, electronic (UV-vis), 1H NMR, conductivity and magnetic measurements. In all cases there is a distorted tetrahedral environment around copper(I) and the ligands (LH) bind through thione sulphur atom to copper(I). We also report the crystal structure of complex [Cu(PPh3)2(dmptH)Cl] which shows that metal ion has a distorted tetrahedral geometry with bond lengths CuS = 2.459(2), CuCl = 2.308(1), CuP(1) = 2.305(1) and Cu P (2) = 2.313(1) A . The NH is intramolecularly hydrogen bonded to Cl with a bond distance NH … Cl = 2.31 A
-
Synthesis and characterization of mixed ligand copper(I) complexes containing halides, triphenylarsine and N,N-dimethyl-N′-Phenylthiourea (dmptH), N,N-dibutyl-N′-Phenylthiourea (dbptH) or 1,3-thiazolidine-2-thione (tzdtH). The X-ray crystal structure
Polyhedron, 1995Co-Authors: Ramsharan Singh, Sheo K. DikshitAbstract:Abstract The arsine complexes [Cu(AsPh3)2(LH)X] (LH = N,N-dimethyl-N′-Phenylthiourea (dmptH), N,N-dibutyl-N′-Phenylthiourea (dbptH) or 1,3-thiazolidine-2-thione (tzdtH); X = Cl, Br, I) have been prepared and characterized on the basis of analytical, IR, electronic (UV-vis), 1H NMR, conductivity and magnetic measurements. In all cases there is a distorted tetrahedral environment around copper(I) and the ligands (LH) bind through thione sulphur atom to copper(I). We also report the crystal structure of complex [Cu(PPh3)2(dmptH)Cl] which shows that metal ion has a distorted tetrahedral geometry with bond lengths CuS = 2.459(2), CuCl = 2.308(1), CuP(1) = 2.305(1) and Cu P (2) = 2.313(1) A . The NH is intramolecularly hydrogen bonded to Cl with a bond distance NH … Cl = 2.31 A
