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Nataly I Svintsitskaya - One of the best experts on this subject based on the ideXlab platform.
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reactions of 5 substituted 1 3 4 thiadiazole 2 Thiones with chloroacetylenephosphonates
Tetrahedron Letters, 2015Co-Authors: Dmitrij M Egorov, Yulija L Piterskaya, Albina V Dogadina, Nataly I SvintsitskayaAbstract:Abstract Reactions of 1-chloroacetylene-2-phosphonates with thiadiazole-2-Thiones in anhydrous acetonitrile occur regio- and chemoselectively to form novel fused phosphorus-containing heterocycles, 2-substituted 5-(dialkoxyphosphoryl)thiazolo[2,3- b ][1,3,4]thiadiazol-4-ylium chlorides. The formation of these fused cyclic compounds is associated only with the thione form of the starting thiadiazoles. Reactions of the salts of thiadiazole-2-thiols with 1-chloroacetylene-2-phosphonates result in the formation of compounds of linear structure.
Saeed Emami - One of the best experts on this subject based on the ideXlab platform.
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synthesis and biological evaluation of 3 trimethoxyphenyl 2 3h thiazole Thiones as combretastatin analogs
European Journal of Medicinal Chemistry, 2013Co-Authors: Mandana Banimustafa, Asma Kheirollahi, Maliheh Safavi, Sussan Kabudanian Ardestani, Hassan Aryapour, Alireza Foroumadi, Saeed EmamiAbstract:Abstract A series of 3-(trimethoxyphenyl)-2(3 H )-thiazole Thiones 5 were designed as new heterocyclic analogs of combretastatin A-4 (CA-4). Indeed, the olefinic core structure of CA-4 has been replaced by 2(3 H )-thiazole thione. The general synthetic strategy to prepare compounds 5 was based on the cyclocondensation reaction between triethylammonium N -(trimethoxyphenyl)dithiocarbamate and appropriate phenacyl halide. The cytotoxic activity evaluation of 3-(trimethoxyphenyl)-2(3 H )-thiazole Thiones 5 against human cancer cell lines T47D, MCF-7 and MDA-MB-231 demonstrated that 4-methyl analog 5f showed the highest activity against all cell lines. Compound 5f had no significant toxicity towards non-tumoral cells MRC-5 and its cytotoxicity was apparently selective for cancer cells. The results of bioassays showed that the representative compound 5f depolymerized tubulin, inhibited cell proliferation, and induced apoptosis in cancer cells.
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synthesis and evaluation of 2 3h thiazole Thiones as tyrosinase inhibitors
Archiv Der Pharmazie, 2012Co-Authors: Saeed Emami, Seyed Jalal Hosseinimehr, Kami Shahrbandi, Ahmad Ali Enayati, Zahra EsmaeeliAbstract:: A series of 2(3H)-thiazole Thiones 3-5 was synthesized and evaluated for tyrosinase inhibition and DPPH radical scavenging activities. Among them, 3-methyl-4-phenyl-2(3H)-thiazole thione (4a) showed good tyrosinase inhibitory activity, even better than that of the well-known tyrosinase inhibitor, namely, kojic acid. From the structure-activity point of view, although it was found that the phenolic hydroxyl group in prototype 3-5 might contribute to the scavenging activity against DPPH radicals, there was no correlation between the potency of tyrosinase inhibition and the presence of the phenolic moiety. The in silico ADME-Tox screening revealed that the drug-likeness and drug-score values of the most potent compound 4a were significantly higher than those of kojic acid.
Petros Karagiannidis - One of the best experts on this subject based on the ideXlab platform.
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Copper(I) bromide complexes with heterocyclic Thiones and triphenylphosphine as ligands. The X-ray crystal structure of copper(I) pyrimidine-2-thione bis (triphenylphosphine) bromide [Cu(PPh3)2(PymtH)Br]
Polyhedron, 2001Co-Authors: C. Lecomte, Petros Karagiannidis, Paraskevas Aslanidis, S. Skoulika, S. PapastefanouAbstract:Abstract Reactions of copper(I) bromide with heterocyclic Thiones (L) [L = pyridine-2- thione (py2SH), pyridine-4-thione (py4SH), pyrimidine-2-thione (pymtH), 1,3-thiazolidine- 2-thione (tzdtH), 1-methyl-1,3-imidazoline-2-thione (meimtH), benz-1,3-imidazoline-2- thione (bzimtH2), benz-1,3-oxazoline-2-thione (bzoxtH), 5-nitro-2-benz-1,3-imidazoline-2- thione (nbzimtH2), benz-1,3-thiazoline-2-thione (bztzH) and quinazolinone-2-thione (qnotH2)] in the presence of triphenylphosphine yields mononuclear complexes of the general formula [Cu(L)(PPh3)2Br]. The complexes have been characterized by elemental analysis, IR, UV-vis and NMR spectroscopy. The crystal structure of [Cu(PPh3)2(pymtH)Br] has been determined by single-crystal X-ray diffraction methods. The yellow-orange crystals are monoclinic, space group P21/nwith a = 13.035(2), b = 43.660(9), c = 13.446(2) A, β = 90.68(2)°, and Dcalc = 1.352 g cm−3, V = 7652 A3, R(F) = 0.06 7; Rw(F) = 0.069, GOF = 1.19. In both molecules of the asymmetric unit, the pymtH molecule acts as a monodentate ligand through the S atom (CuS = 2.352(3) A).
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On the molecular structure of gold(I) complexes with heterocyclic Thiones. The structure of bis(1,3-thiazolidine-2-thione) gold(I) chloride hydrate
Polyhedron, 2001Co-Authors: Pericles D. Akrivos, Petros Karagiannidis, Sotiris K. Hadjikakou, Maria Gdaniec, Zofia KosturkiewiczAbstract:Abstract The preparation of a seies of gold(I) coordination compounds with heterocyclic Thiones is reported. The crystal structure of the coordination compound with 1,3-thiazolidine-2-thione (tztH) was determined. The S—Au—S angle is 176.52(2)° and the two Au—S distances are 2.281(5) and 2.288(5) A, respectively, giving rise to the usual linear gold(I) environment. Extended Huckel computations on both the model and the observed Au(thione)2 cationic unit are used in an attempt to unravel the factors influencing the local and overall molecular structure observed, which is determined by an extended hydrogen-bond network. On the grounds of these computations and the existing strutural evidence, it is concluded that hydrogen bonds formed by the coordinated thione ligands determine the geometry adopted by these and analogous compounds.
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Synthesis and characterization of copper(I) complexes with triphenylphosphine and heterocyclic thione ligands: the crystal structure of (thiazolidine-2-thione)(bis-triphenylphosphine) copper(I) chloride
Inorganica Chimica Acta, 1998Co-Authors: Paraskevas Aslanidis, Sotiris K. Hadjikakou, Petros KaragiannidisAbstract:Abstract Reactions of [Cu(PPh3)3Cl] with heterocyclic Thiones (L) (L = pyridine-2-thione (py2SH), 1,3-thiazolidine-2-thione (tzdtH), benz-1,3-imidazoline-2-thione (bzimtH2), bens-1,3,-thiazoline-2-thione (bzimtH), 4,5-diphenyl-imidazol-2-thione (dpimtH), 3-methylbenz-1,3-thiazoline-2-thione (mbztztH), 6-ethoxybenz-1,3-thiazoline-2-thione (etbztztH). 4-hydroxy-5-methyl-pyridine-2-thione (hympmtH), 4,6-dimethyl-pyrimidine-2-thione (dmpmtH), 4-mercapto-1H-pyrazolo[3,4d] pyrimidine (pyrpmtH) and quinoline-2-thione (quintH)) yield mononuclear complexes of the general formula [Cu(PPh3)2(L)Cl]. The complexes were characterized by various physicochemical methods. The crystal structure of [Cu(PPh3)2(tzdtH)Cl] was determined by single-crystal X-ray diffraction methods. The yellow crystals are monoclinic, space group P2 1 /c with a = 14.31(2), b = 10.099(10), c = 24.52(2) A , β = 93.53(7)° and Z = 4 . The copper atom has a pseudotetrahedral geometry with the bond lengths CuS = 2.418(5), CuCl = 2.344(3), CuP (1) = 2.287(3) and CuP (2) = 2.298(2) A . The structure was solved by direct methods with a final R value of 0.0562.
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Thione-Disulfide Interchange of some Heterocyclic Tautomeric Thiones and their Symmetrical Disulfides
Monatshefte Fur Chemie, 1996Co-Authors: Stefan Stoyanov, Tatyana Stoyanova, Liudmil Antonov, Petros Karagiannidis, Pericles D. AkrivosAbstract:The UV/Vis spectroscopic properties of some symmetrical disulfides derived from potentially tautomeric Thiones are investigated. Reversed thione-disulfide transformation is observed, and the influence of several factors including the nature of solvent, concentration, and UV irradiation, is studied. Possible implication of the tautomeric thiol form and the importance of this thione-disulfide redox system in biological aspects is suggested. A general scheme including monomer-dimer equilibrium, thione-thiol tautomeric equilibrium, and reversible thiol-disulfide redox behaviour is proposed in order to explain the factors affecting the overall thione-disulfide transformation.
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MIXED LIGAND COORDINATION COMPOUNDS OF COPPER(I) WITH HETEROCYCLIC Thiones AND TERTIARY PHOSPHINES. THE CRYSTAL STRUCTURE OF BIS (QUINOLINE-2-THIONE) BISTRIPHENYLPHOSPHINO COPPER(I) ETHYLSULFATE HEMIHYDRATE
Journal of Coordination Chemistry, 1994Co-Authors: Pericles D. Akrivos, Petros Karagiannidis, Sotiris K. Hadjikakou, Marija Luić, Biserka Kojić-prodićAbstract:Abstract Copper(II) sulfate is reduced in alcoholic media in the presence of heterocyclic Thiones (i.e. pyridine-2-thione or quinoline-2-thione) and triphenylphosphine. The resulting coordination compounds consist of Cu(thione)2(PPh3)2 cationic units; the counteranions are alkyl sulfate monoanions. The crystal structure of the compound prepared using quinoline-2-thione in ethanol reveals that the tetrahedal cationic units and the counteranions are arranged in rows cross-linked through hydrogen bonds formed between the oxygen atoms of the anion and water molecules. The compound crystallizes in the triclinic space group P 1, a = 10.69 (1), b = 13.47 (2), c = 18.75 (2) A, α = 75.9 (1), β=85.6 (1), γ=74.7 (1)°, V = 2525.5 A3, Z = 2. The local copper environment is distorted tetrahedal with unequal Cu-S (2.380(2), and 2.341(2) A) and Cu-P (2.301(2) and 2.316(2) A) bonds; angles around copper range from 96.37(7) to 121.16(0)°.
Dmitrij M Egorov - One of the best experts on this subject based on the ideXlab platform.
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reactions of 5 substituted 1 3 4 thiadiazole 2 Thiones with chloroacetylenephosphonates
Tetrahedron Letters, 2015Co-Authors: Dmitrij M Egorov, Yulija L Piterskaya, Albina V Dogadina, Nataly I SvintsitskayaAbstract:Abstract Reactions of 1-chloroacetylene-2-phosphonates with thiadiazole-2-Thiones in anhydrous acetonitrile occur regio- and chemoselectively to form novel fused phosphorus-containing heterocycles, 2-substituted 5-(dialkoxyphosphoryl)thiazolo[2,3- b ][1,3,4]thiadiazol-4-ylium chlorides. The formation of these fused cyclic compounds is associated only with the thione form of the starting thiadiazoles. Reactions of the salts of thiadiazole-2-thiols with 1-chloroacetylene-2-phosphonates result in the formation of compounds of linear structure.
Santosh G Tilve - One of the best experts on this subject based on the ideXlab platform.
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graphite catalyzed solvent free synthesis of dihydropyrimidin 2 1h ones Thiones and their antidiabetic activity
Bioorganic & Medicinal Chemistry Letters, 2014Co-Authors: Kashinath L Dhumaskar, Surya Nandan Meena, Sanjeev C Ghadi, Santosh G TilveAbstract:Abstract A solvent free three component condensation reaction between an aldehyde, ethyl acetoacetate and urea catalyzed by graphite, a green catalyst is described for the synthesis of dihydropyrimidin-2(1 H )-ones. This protocol is scalable and the catalyst is reusable. This method is also applied for the synthesis of dihydropyrimidin-2(1 H )-Thiones. α-Amylase, a key enzyme in carbohydrate metabolism is generally targeted for management of type 2 diabetes. The therapeutic potential of the dihydropyrimidinones and dihydropyrimidinThiones to inhibit α-amylase activity was evaluated by in vitro assay. Of the synthesized compounds 3,4-dihydropyrimidin-2(1 H )-thione ( 1k ) demonstrated highest inhibition of α-amylase activity.
