101
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Altaf M, Stoeckli-Evans H, Batool SS, Isab AA, Ahmad S, Saleem M, Awan SA, Shaheen MA. Mercury(II) complexes of pyrrolidinedithiocarbamate, crystal structure of bis{[μ2-(pyrrolidinedithiocarbamato-S,S ′)(pyrrolidinedithiocarbamato-S,S ′)mercury(II)]}. J COORD CHEM 2010. [DOI: 10.1080/00958971003759085] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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102
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Ali S, Malik MR, Isab AA, Ahmad S. Synthesis and spectroscopic characterization of cadmium(II) complexes of thiones and thiocyanate. J COORD CHEM 2009. [DOI: 10.1080/00958970802226395] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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103
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Al-Maythalony BA, Wazeer MI, Isab AA. Synthesis and characterization of gold(III) complexes with alkyldiamine ligands. Inorganica Chim Acta 2009. [DOI: 10.1016/j.ica.2009.02.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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104
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Isab AA, Arnold AP. Exchange Reactions of Aurothiomalate with 3-Selenopropionate in Aqueous Solution. J COORD CHEM 2009. [DOI: 10.1080/00958978909408852] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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105
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Isab AA, Wazeer MIM, Ashraf W. Cadmium cyanide complexes with heterocyclic thiones: solid state and solution NMR studies. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2009; 72:218-221. [PMID: 19010714 DOI: 10.1016/j.saa.2008.09.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 07/27/2008] [Accepted: 09/21/2008] [Indexed: 05/27/2023]
Abstract
Cadmium(II)cyanide complexes of various thiones (imidazolidine-2-thione, diazinane-2-thione and their derivatives) have been prepared and characterized by elemental analysis, IR and solid as well as solution NMR spectroscopy. It appears from the IR data that all complexes are non-ionic [(>C=S)(2)Cd(CN)(2)]. An upfield shift in the (13)C NMR and downfield shifts in the (1)H NMR are consistent with the sulfur coordination to cadmium(II). The solid (113)Cd NMR data show the presence of different coordination numbers in some complexes.
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Fettouhi M, Wazeer MI, Isab AA. A novel polymeric Cd[SSe2N2] central core five-coordinate complex: Synthesis, X-ray structure and 113Cd, 77Se CP MAS NMR characterization of catena(bis(μ2-selenocyanato-N,Se)-(N,N′-dimethylimidazolidine- 2-thione-S)-cadmium(II)). INORG CHEM COMMUN 2008. [DOI: 10.1016/j.inoche.2007.11.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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107
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Wazeer MIM, Isab AA. Complexations of Hg(CN)(2) with imidazolidine-2-thione and its derivatives: solid state, solution NMR and antimicrobial activity studies. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 68:1207-12. [PMID: 17485240 DOI: 10.1016/j.saa.2007.01.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Accepted: 01/24/2007] [Indexed: 05/15/2023]
Abstract
The preparation and characterization of new mercuric complexes of formula L(2)Hg(CN)(2) with L being imidazolidine-2-thione (Imt) and its substituted derivatives, 1,3-diazinane-2-thione (Diaz), 1,3-diazipane-2-thione (Diap), are described. The solution and solid-state (13)C NMR show a significant shift of the CS carbon resonance of the ligands, while the other resonances are relatively unaffected, indicating that most likely the solid-state structure is maintained in solution as well. The principal components of the (199)Hg shielding tensors were determined from solid-state NMR data. Antimicrobial activity studies of the free ligands and their complexes show that ligands exhibit substantial antibacterial activities compare to their Hg(II) complexes.
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108
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Wazeer MIM, Isab AA. Solid state and solution NMR studies of some new complexes of mercury selenocyanate with imidazolidine-2-thione and its derivatives. J COORD CHEM 2007. [DOI: 10.1080/00958970701288421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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109
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Isab AA, Wazeer MI, Fettouhi M, Al-Maythalony BA, Al-Arfaj AR, Al-Zamil NO. Solid state and solution NMR, X-ray and antimicrobial studies of 1:1 and 2:1 complexes of silver(I) cyanide with alkanediamine ligands. Inorganica Chim Acta 2007. [DOI: 10.1016/j.ica.2007.04.036] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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110
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Wazeer MI, Isab AA, Fettouhi M. New cadmium chloride complexes with imidazolidine-2-thione and its derivatives: X-ray structures, solid state and solution NMR and antimicrobial activity studies. Polyhedron 2007. [DOI: 10.1016/j.poly.2006.12.022] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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111
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Fettouhi M, Wazeer MIM, Isab AA. Zinc halide complexes of imidazolidine-2-thione and its derivatives: X-ray structures, solid state, solution NMR and antimicrobial activity studies. J COORD CHEM 2007. [DOI: 10.1080/00958970600780965] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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112
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Isab AA, Wazeer MIM. Synthesis and characterization of thiolate-Ag(I) complexes by solid-state and solution NMR and their antimicrobial activity. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 66:364-70. [PMID: 16843708 DOI: 10.1016/j.saa.2006.03.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2006] [Revised: 02/19/2006] [Accepted: 03/02/2006] [Indexed: 05/10/2023]
Abstract
Silver(I) complexes of several thiolates have been prepared. These complexes have been characterized by elemental analysis and 13C NMR spectroscopy. All the Ag(I)-thiolate complexes are polymeric in nature. Therefore, 13C CP MAS NMR is being used extensively to analyze the binding site of the ligand and the nature of complexation. A significant shift difference was observed for S binding site whereas smaller shift was observed for carboxylate binding site. The antimicrobial activities for Ag(I)-glutathione complex was measured and compared with Ag(I)-captopril complex.
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Ashraf W, Isab AA. 31P NMR studies of Redox reactions of Bis (Trialkylphosphine) Gold(I) Bromide (Alkyl = Methyl, Ethyl) with Disulphide and Diselenide ligands. J COORD CHEM 2007. [DOI: 10.1080/00958970410001671228] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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114
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Hussain MS, Isab AA. GOLD(I) COMPLEXES OFN-ALKYL SUBSTITUTED IMIDAZOLIDINE-2-THIONES: SYNTHESIS, SPECTROSCOPIC STUDIES AND X-RAY STRUCTURE. J COORD CHEM 2007. [DOI: 10.1080/00958978508080673] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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115
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116
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Ahmad S, Akhtar MN, Isab AA, Al-arfaj AR, Hussain MS. Gold(I) Complexation with Trialkyl/Triaryl Phosphine Selenide Ligands. J COORD CHEM 2006. [DOI: 10.1080/00958970008055129] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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117
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Al Arfaj AR, Saeed AA, Akhtar MN, Isab AA. SIMULTANEOUS REPLACEMENTS OF TRIETHYL PHOSPHINE AND TETRAACETYL THIOGLUCOSE LIGANDS FROM AURANOFIN (AN ANTIARTHRITIC DRUG) WITH SELENOCYANATE 13C and 31P NMR STUDIES. J COORD CHEM 2006. [DOI: 10.1080/00958979808022674] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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118
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Isab AA, Akhtar MN. COMPARATIVE13C NMR STUDIES OF COMPLEXATION OF IMIDAZOLIDINE-2-SELENONE AND ITS ANALOGOUS THIONE TO GOLD(I) THIOMALATE. J COORD CHEM 2006. [DOI: 10.1080/00958979608028172] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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119
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Isab AA, Wazeer MIM. Solid and solution NMR studies of the complexation of Ag+ with the trans isomer of captopril: biological activities of this high blood pressure drug along with its Ag+ complex. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2006; 65:191-5. [PMID: 16497545 DOI: 10.1016/j.saa.2005.10.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2005] [Revised: 10/14/2005] [Accepted: 10/14/2005] [Indexed: 05/06/2023]
Abstract
Complexation of Ag(+) with captopril, 1-[(2S)-3-mercapto-2-methylpropionyl]-L-proline, has been studied by (1)H and (13)C-NMR spectroscopy. The equilibrium constants for the trans to cis isomers of captopril bound to Ag(+) were measured by (1)H NMR spectroscopy. It is observed that the trans isomer of the drug binds more strongly to Ag(+) between pH 5 and 8, as shown by the broadening of the trans isomer's resonances in (13)C NMR spectra on complexation. A monodentate complexation of the trans captopril with Ag(+) via the thiol site is proposed based on the solid-state NMR and IR data. A superior antimicrobial activity is exhibited by the Cap-Ag(I) complex compared to captopril ligand itself against Heterotrotropic Plate Counts (HPC), Pseudomonas aeruginosa and Fecal streptococcus bacteria.
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Wazeer MIM, Isab AA, Ahmad S. Solution and solid state NMR studies of some selenium analogues of auranofin (an anti-arthritic gold drug). J COORD CHEM 2006. [DOI: 10.1080/00958970512331331343] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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121
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Isab AA, Wazeer * MIM. Complexation of Zn(II), Cd(II) and Hg(II) with thiourea and selenourea: A 1H, 13C, 15N, 77Se and 113Cd solution and solid-state NMR study. J COORD CHEM 2006. [DOI: 10.1080/00958970500038951] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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122
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123
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Al-Amri AHD, Fettouhi M, Wazeer MI, Isab AA. Synthesis, X-ray structure and 199Hg, 77Se CP MAS NMR studies on the first tris(imidazolidine-2-selone) mercury complex: {Chloro-tris[N-methyl-2(3H)-imidazolidine-2- selone]mercury(II)}chloride. INORG CHEM COMMUN 2005. [DOI: 10.1016/j.inoche.2005.09.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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124
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Wazeer MIM, Isab AA. Solution and solid-state NMR studies of some cadmium-selenone complexes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 62:880-5. [PMID: 15950525 DOI: 10.1016/j.saa.2005.03.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2005] [Revised: 03/31/2005] [Accepted: 03/31/2005] [Indexed: 05/02/2023]
Abstract
Cadmium(II) complexes of Imidazolidine-2-selenone (ImSe) and its derivatives have been prepared with the general formula Cd(RImSe)2Cl2 (where R=Me, Et, Pr, etc.). These complexes are characterized by elemental analysis, IR and NMR (1H, 13C, 77Se and 113Cd) spectroscopy. An upfield shift in C=Se resonance of selenones in 13C NMR and in 77Se and high-frequency shifts in N-H resonances in 1H are consistent with the selenium coordination to Cd(II). The 77Se nucleus in Cd(ImSe)2Cl2 is shielded by 38 ppm on coordination, relative to the free ligand. The principal components of the 77Se, 113Cd and 13C shielding tensors for the complexes were determined from solid-state NMR data. Large selenium chemical shift anisotropies were observed for these complexes.
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125
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Isab AA, Ahmad S, Ashraf W. 13C-n.m.r. studies of the binding of 1,3-diazinane-2-selenone and 1,3-diazipine-2-selenone to gold(I) drugs. TRANSIT METAL CHEM 2005. [DOI: 10.1007/s11243-004-6966-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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126
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Isab AA, Ashraf W. Oxidation of diselenide bond with sodiumtetracloroaurate (III): Significance in chemotherapy. INORG CHEM COMMUN 2005. [DOI: 10.1016/j.inoche.2005.01.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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127
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128
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129
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Ahmad S, Isab AA, Perzanowski HP. Ligand scrambling reactions of cyano(thione)gold(I) complexes and determination of their equilibrium constants. CAN J CHEM 2002. [DOI: 10.1139/v02-165] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ligand scrambling reactions in cyano(thione)gold(I) complexes ([>C=S-Au-CN]) to form [Au(>C=S)2]+ and [Au(CN)2] species have been investigated for a series of thiones in DMSO using 13C and 15N NMR spectroscopy. Rapid approach to equilibrium occurred and resulted in distinct signals for the [>C=S-Au-CN] and [Au(CN)2] complexes, both in 13C and 15N NMR. Equilibrium constants (Keq) were determined for scrambling of all the complexes by integrating the CN resonances in the 13C NMR recorded at 298 K. The influence of various factors (initial concentration, ionic strength, temperature, and solvent polarity) on the Keq value was examined for a representative complex (ImtAuCN (Imt = Imidazolidine-2-thione)).Key words: cyanogold(I) complexes, thiones, ligand scrambling, NMR, Keq.
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130
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Ahmad S, Isab AA, Al-Arfaj AR, Arnold AP. Synthesis of cyano(selenone)gold(I) complexes and investigation of their scrambling reactions using 13C and 15N NMR spectroscopy. Polyhedron 2002. [DOI: 10.1016/s0277-5387(02)01152-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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131
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Rabenstein DL, Isab AA. Conformational and acid-base equilibriums of captopril in aqueous solution. Anal Chem 2002. [DOI: 10.1021/ac00240a039] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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132
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Isab AA, Shaw CF, Hoeschele JD, Locke J. Reactions of trimethylphosphine analogs of auranofin with bovine serum albumin. Inorg Chem 2002. [DOI: 10.1021/ic00293a029] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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133
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Rabenstein DL, Isab AA, Shoukry MM. Nuclear magnetic resonance studies of the solution chemistry of metal complexes. 18. Complexation of palladium(II) by glycyl-L-histidine and glycyl-L-histidylglycine. Inorg Chem 2002. [DOI: 10.1021/ic00138a061] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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134
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Isab AA, Hormann AL, Hill DT, Griswold DE, DiMartino MJ, Shaw CF. Bis(triethylphosphine)gold(I) chloride: ionization in aqueous solution, reduction in vitro of the external and internal disulfide bonds of bovine serum albumin and antiarthritic activity. Inorg Chem 2002. [DOI: 10.1021/ic00306a023] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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135
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Rabenstein DL, Backs SJ, Isab AA. Nuclear magnetic resonance studies of the complexation of trimethyllead by glutathione in aqueous solution and in intact human erythrocytes. J Am Chem Soc 2002. [DOI: 10.1021/ja00400a057] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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136
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Zhu Z, Goodrich M, Isab AA, Shaw CF. Biphasic reactions of DTNB with lobster Cd6- and Cd5Cu-metallothionein-2 which have two type-B (M3S9) clusters. Inorg Chem 2002. [DOI: 10.1021/ic00035a027] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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137
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Isab AA, Shaw CF, Locke J. GC-MS and oxygen-17 NMR tracer studies of triethylphosphine oxide formation from auranofin and water-17O in the presence of bovine serum albumin: an in vitro model for auranofin metabolism. Inorg Chem 2002. [DOI: 10.1021/ic00292a027] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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138
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Daignault SA, Arnold AP, Isab AA, Rabenstein DL. Nuclear magnetic resonance studies of the solution chemistry of metal complexes. 22. Complexation of zinc by the growth-modulating tripeptide glycylhistidyllysine. Inorg Chem 2002. [DOI: 10.1021/ic00218a005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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139
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Isab AA, Hormann AL, Coffer MT, Shaw CF. Reversibly and irreversibly formed products from the reactions of mercaptalbumin (AlbSH) with Et3PAuCN and of AlbSAuPEt3 with hydrocyanic acid. J Am Chem Soc 2002. [DOI: 10.1021/ja00218a044] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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140
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Shaw CF, Isab AA, Hoeschele JD, Starich M, Locke J, Schulteis P, Xiao J. Oxidation of the phosphine from the auranofin analog, triisopropylphosphine(2,3,4,6-tetra-O-acetyl-1-thio-.beta.-D-glucopyranosato-S)gold(I), via a protein-bound phosphonium intermediate. J Am Chem Soc 2002. [DOI: 10.1021/ja00085a003] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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141
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Rabenstein DL, Daignault SA, Isab AA, Arnold AP, Shoukry MM. Nuclear magnetic resonance studies of the solution chemistry of metal complexes. 21. The complexation of zinc by glycylhistidine and alanylhistidine peptides. J Am Chem Soc 2002. [DOI: 10.1021/ja00309a001] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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142
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143
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Ahmad S, Isab AA. (13)C, (31)P and (15)N NMR studies of the ligand exchange reactions of auranofin and chloro(triethylphosphine)gold(I) with thiourea. J Inorg Biochem 2002; 88:44-52. [PMID: 11750024 DOI: 10.1016/s0162-0134(01)00305-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The interaction of thiourea (Tu) with auranofin (Et(3)PAuSATg) and its analogue, Et(3)PAuCl has been studied using (13)C, (31)P and (15)N NMR spectroscopy. It is observed that Tu is able to replace both the ligands, Et(3)P and SATg(-) simultaneously from gold(I) in auranofin, forming [Et(3)P-Au-Tu](+) and Tu-Au-SATg complexes. However, no separate resonances for these species were observed either due to their rapid exchange with auranofin and thus giving only the average resonances or because the chemical shifts of either two species are same so that they cannot be resolved. The displaced SATg(-) is oxidized to its disulfide, (SATg)(2). However, some of the displaced Et(3)P is oxidized to Et(3)PO while the remaining reacts with Tu to form Et(3)P-Tu species, characterized by delta 31P of 1.0 ppm, assigned after an independent reaction between Et(3)P and Tu. In an experiment using a 0.05 M solution of auranofin, the Et(3)PO resonance appeared in auranofin spectrum after 4 days of addition of 1.0 equivalent of Tu, showing that the reaction is slow. A resonance for free Et(3)P is also detected in 31P NMR on the addition of CN(-). It is also observed that Tu reacts with Et(3)PAuCl to form [Et(3)P-Au-Tu](+) via displacement of Cl(-), consistent with an upfield shift of 6.2 ppm in >C [double bond] S resonance of Tu in (13)C NMR. In (15)N NMR, a smaller downfield, instead of an upfield shift, in NH(2) resonance of Tu on its addition to auranofin and Et(3)PAuCl indicates that it is not binding to gold(I) through nitrogen.
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Isab AA, Ahmad S. Comparative (13)C and (31)P NMR studies of the ligand exchange reactions of auranofin with ergothionine, imidazolidine-2-thione and diazinane-2-thione. J Inorg Biochem 2002; 88:53-60. [PMID: 11750025 DOI: 10.1016/s0162-0134(01)00304-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The interaction of auranofin (Et(3)PAuSATg) with ergothionine (ErS), imidazolidine-2-thione (Imt) and diazinane-2-thione (Diaz) has been studied using (13)C and (31)P NMR spectroscopy. It is observed that these thiones are able to replace both Et(3)P and SATg(-) ligands simultaneously from gold(I) in auranofin forming >C [double bond] S-Au-SATg and [Et(3)P-Au-S [double bond] C<](+) type complexes. The displaced SATg(-) is oxidized to its disulfide (SATg)(2). However, some of the displaced Et(3)P is oxidized to Et(3)PO while the remaining reacts with thiones to form Et(3)P-S [double bond] C< species characterized by delta (31)P NMR of 1.0-1.5 ppm. The Et(3)PO resonance appeared in the 31P NMR spectrum, after 10 days of the addition of ErS, after 19 days of the addition of Imt and after 6 days of the addition of Diaz, to auranofin solution showing that the thiones react with auranofin very slowly.
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Canumalla AJ, Al-Zamil N, Phillips M, Isab AA, Shaw CF. Redox and ligand exchange reactions of potential gold(I) and gold(III)-cyanide metabolites under biomimetic conditions. J Inorg Biochem 2001; 85:67-76. [PMID: 11377697 DOI: 10.1016/s0162-0134(00)00224-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Biomimetic pathways for the oxidation of [Au(CN)(2)](-), a gold metabolite, and further cyanation of the gold(III) products to form Au(CN)(4)(-) were investigated using 13C NMR and UV-Visible spectroscopic methods. Hypochlorite ion, an oxidant released during the oxidative burst of immune cells, was employed. The reaction generates mixed dicyanoaurate(III) complexes, trans-[Au(CN)(2)X(2)](-), where X(-) represents equilibrating hydroxide and chloride ligands, and establishes the chemical feasibility of dicyanoaurate oxidation by OCl(-) to gold(III) species. This oxidation reaction suggests a new procedure for synthesis of H[Au(CN)(2)Cl(2)]. Reaction of trans-[Au(CN)(2)X(2)](-) (X(-)=Cl(-) and Br(-)) or [AuCl(4)](-) with HCN in aqueous solution at pH 7.4 leads directly to [Au(CN)(4)](-) without detection of the anticipated [Au(CN)(x)X(4-x)](-)intermediates, which is attributed to the cis- and trans-accelerating effects of the cyanides. The reduction of [Au(CN)(4)](-) by glutathione and other thiols is a complex, pH-dependent process that proceeds through two intermediates and ultimately generates [Au(CN)(2)](-). These studies provide further insight into the possible mechanisms of an immunogenically generated gold(I)/gold(III) redox cycle in vivo.
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Ahmad S, Isab AA. Synthesis of cyano(ergothionine)gold(I) complex and its disproportionation in solution. INORG CHEM COMMUN 2001. [DOI: 10.1016/s1387-7003(01)00214-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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148
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Isab AA, Hussain M, Akhtar M, Wazeer M, Al-Arfaj A. 13C, 15N and 31P NMR study of the disproportionation of cyanogold(I) complexes: [R3PAu13C15N]. Polyhedron 1999. [DOI: 10.1016/s0277-5387(98)00441-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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149
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Isab AA, Marzilli LG. Supermacrochelate Complexes Containing an Artificial Nucleic Acid Backbone and Derived from Excellent Ligands Formed by Treating Platinum Anticancer Agents with Nucleotide Triphosphates. Inorg Chem 1998; 37:6558-6559. [PMID: 11670784 DOI: 10.1021/ic980946y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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150
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Akhtar MN, Isab AA, Wazeer MI. Characterization of polymeric Gold(I)-captopril complex using viscosity and various spectroscopic techniques. J Inorg Biochem 1996. [DOI: 10.1016/0162-0134(95)00242-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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