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41.
42.
A series of regioisomers of pyrazolyl-substituted quinolines has been synthesized through the simple condensation reaction between hydrazinylquinolines with aliphatic 1,3-diketones with InCl3 as a catalyst under microwave irradiation. This method produces pure products in good yield in a rapid manner compared to conventional procedures and withneat reaction condition. The approach has the advantages of operational simplicity and increased safety for a shortened synthesis of pyrazolyl-substituted quinolines. 相似文献
43.
Synthesis,structural and chemosensitivity studies of arene d6 metal complexes having N‐phenyl‐N´‐(pyridyl/pyrimidyl)thiourea derivatives
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Sanjay Adhikari Omar Hussain Roger M. Phillips Werner Kaminsky Mohan Rao Kollipara 《应用有机金属化学》2018,32(6)
The d6 metal complexes of thiourea derivatives were synthesized to investigate its cytotoxicity. Treatment of various N‐phenyl‐N´ pyridyl/pyrimidyl thiourea ligands with half‐sandwich d6 metal precursors yielded a series of cationic complexes. Reactions of ligand (L1‐L3) with [(p‐cymene)RuCl2]2 and [Cp*MCl2]2 (M = Rh/Ir) led to the formation of a series of cationic complexes bearing general formula [(arene)M(L1)к2(N,S)Cl]+, [(arene)M(L2)к2(N,S)Cl]+ and [(arene)M(L3)к2(N,S)Cl]+ [arene = p‐cymene, M = Ru ( 1 , 4 , 7 ); Cp*, M = Rh ( 2 , 5 , 8 ); Cp*, Ir ( 3 , 6 , 9 )]. These compounds were isolated as their chloride salts. X‐ray crystallographic studies of the complexes revealed the coordination of the ligands to the metal in a bidentate chelating N,S‐ manner. Further the cytotoxicity studies of the thiourea derivatives and its complexes evaluated against HCT‐116 (human colorectal cancer), MIA‐PaCa‐2 (human pancreatic cancer) and ARPE‐19 (non‐cancer retinal epithelium) cancer cell lines showed that the thiourea ligands displayed no activity. Upon complexation however, the metal compounds possesses cytotoxicity and whilst potency is less than cisplatin, several complexes exhibited greater selectivity for HCT‐116 or MIA‐PaCa‐2 cells compared to ARPE‐19 cells than cisplatin in vitro. Rhodium complexes of thiourea derivatives were found to be more potent as compared to ruthenium and iridium complexes. 相似文献
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Claborn K Cedres JH Isborn C Zozulya A Weckert E Kaminsky W Kahr B 《Journal of the American Chemical Society》2006,128(46):14746-14747
The optical rotatory power of achiral crystals of achiral pentaerythritol molecules was measured. The maximum rotations were found to be +/-6 degrees /mm. The quantum mechanically computed rotation of pentaerythritol molecules using linear response theory was 6 times larger although the experimental and theoretical tensors were similarly oriented to within 5 degrees . 相似文献
46.
Kitagawa T Dey A Lugo-Mas P Benedict JB Kaminsky W Solomon E Kovacs JA 《Journal of the American Chemical Society》2006,128(45):14448-14449
Superoxide reductases (SORs) are cysteine-ligated, non-heme iron enzymes that reduce toxic superoxide radicals (O2-). The functional role of the trans cysteinate, as well as the mechanism by which SOR reduces O2-, is unknown. Herein is described a rare example of a functional metalloenzyme analogue, which catalytically reduces superoxide in a proton-dependent mechanism, via a trans thiolate-ligated iron-peroxo intermediate, the first example of its type. Acetic-acid-promoted H2O2 release, followed by Cp2Co reduction, regenerates the active Fe(II) catalyst. The thiolate ligand and its trans positioning relative to the substrate are shown to contribute significantly to the catalyst's function, by lowering the redox potential, changing the spin state, and dramatically lowering the nuFe-O stretching frequency well-below that of any other reported iron-peroxo, while leaving nuO-O high, so as to favor superoxide reduction and Fe-O, as opposed to O-O, bond cleavage. Thus we provide critical insight into the relationship between the SOR structure and its function, as well as important benchmark parameters for characterizing highly unstable thiolate-ligated iron-peroxo intermediates. 相似文献
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Anne K. Hermetet Lily J. Ackerman John K. Swearingen Carmina A. Presto Diantha R. Kelman James M. Giesen Karen I. Goldberg Werner Kaminsky Douglas X. West 《Journal of chemical crystallography》2002,32(1-2):17-25
Reaction of 2-amino-6-picoline with 2-, 3-, and 4-tolyl isothiocyanates produces the three N-2-(6-picolyl)-N-tolylthioureas, 6PicTu2T, 6PicTu3T, and 6PicTu4T. 6PicTu2T is mono-clinic, space group P21/n with a = 8.1700(3) Å, b = 25.5840(6) Å, c = 12.6840(5) Å, = 98.8750(16)°, and V = 2619.5(2) Å3 with Z = 8, for d
calc = 1.305 g/cm3. 6PicTu3T is monoclinic, space group C2/c with a = 23.879(3) Å, b = 6.744(3) Å, c = 17.116(10) Å, = 99.26(4)°, and V = 2720(3) Å3 with Z = 8, for d
calc = 1.257 g/cm3. 6PicTu4T is triclinic, space group P-1 with a = 8.829(6) Å, b = 8.8950(15) Å, c = 10.495(3) Å, = 68.63(3)°, = 72.19(4)°, = 63.06(4)°, and V = 681.2(5) Å3 with Z = 2, for d
calc = 1.255 g/cm3. Intermolecular hydrogen bonding involving the thione sulfur and the NH hydrogen and the planarity of the thiourea are affected by the position of substitution on the aryl ring. 1H NMR studies in CDCl3 show the NH hydrogen resonance considerably downfield from other signals in the spectrum of each thiourea. The enthalpies of fusion of the present thioureas reflect the extent of intermolecular hydrogen bonding and are compared to other heterocyclic thioureas. 相似文献
50.
M. Anikina V. Aksinenko E. Dementiev M. Gaździcki N. Glagoleva A. Golokhvastov L. Goncharova A. Grachov K. Iovchev S. Kadykova N. Kaminsky S. Khorozov E. Kuznetsova J. Lukstins A. Matyushin V. Matyushin E. Okonov T. Ostanevich E. Shevchenko S. Sidorin G. Vardenga O. Balea N. Nikorovich T. Ponta L. Chkhaidze T. Dzobava M. Destpotashvili I. Tuliani E. Khusainov N. Nurgozin B. Suleimanov E. Skrzypczak T. Tymieniecka 《Zeitschrift fur Physik C Particles and Fields》1984,25(1):1-11
Data on Λ's andK 0's, produced in central nucleus-nucleus collisions (C?C, C?Ne, O?Ne, C?Cu, C?Zr, C?Pb, O?Pb) at a 4.5 GeV/c momentum per incident nucleon obtained in the streamer chamber spectrometer SKM-200, are presented. Multiplicities, transverse momenta, rapidities and other characteristics are considered and compared with those for inelastic He?Li interactions. The polarization of Λ's was found to be consistent with zero. The upper limit of \(\bar \Lambda /\Lambda \) production ratio was estimated to be ≤10?2 with a 90% confidence level. The results are compared with data of other experiments and some model calculations. 相似文献