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Sharma N, Anurag. 7-Azaindole Analogues as Bioactive Agents and Recent Results. Mini Rev Med Chem 2019; 19:727-736. [PMID: 30264679 DOI: 10.2174/1389557518666180928154004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 04/18/2018] [Accepted: 05/27/2018] [Indexed: 12/15/2022]
Abstract
Azaindoles have been accepted as important structures having various biological activities in medicinal chemistry in novel drug discovery. Various azaindole derivatives have been used commercially and newer analogues are synthesized continuously. As in literature, azaindole is a very potent moiety, its derivatives displayed a number of biological activities such as kinase inhibitors, cytotoxic agents, anti-angiogenic activity, CRTh2 receptor antagonists, melanin agonists, nicotine agonists, effectiveness in alzheimer disease, cytokinin analogs, Orai inhibitors in asthma and chemokine receptor- 2 (CCR2) antagonists. This review consists of biological activities of various azaindole analogs, reported so far, and their structure activity relations, along with future perspectives in this field.
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Affiliation(s)
- Neha Sharma
- Department of Pharmaceutical Technology, Meerut Institute of Engineering and Technology, NH-58, Near Baghpat Crossing, Bypass Road, Meerut-250005, India
| | - Anurag
- Department of Pharmaceutical Technology, Meerut Institute of Engineering and Technology, NH-58, Near Baghpat Crossing, Bypass Road, Meerut-250005, India
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2
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Synthesis and electrochemical, spectral, and biological evaluation of novel 9,10-anthraquinone derivatives containing piperidine unit as potent antiproliferative agents. J Mol Struct 2019. [DOI: 10.1016/j.molstruc.2018.07.070] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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3
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Biancalana L, Batchelor LK, Dyson PJ, Zacchini S, Schoch S, Pampaloni G, Marchetti F. α-Diimine homologues of cisplatin: synthesis, speciation in DMSO/water and cytotoxicity. NEW J CHEM 2018. [DOI: 10.1039/c8nj04195d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
α-Diimine Pt(ii) complexes display variable stability in DMSO and DMSO/water mixtures, depending on the nature of the N-substituents. The most stable compounds are moderately cytotoxic, or are essentially inactive, against A2780 and A2780cisR cancer cell lines.
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Affiliation(s)
- Lorenzo Biancalana
- Dipartimento di Chimica e Chimica Industriale
- Università di Pisa
- I-56124 Pisa
- Italy
| | - Lucinda K. Batchelor
- Institut des Sciences et Ingénierie Chimiques
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- CH-1015 Lausanne
- Switzerland
| | - Paul J. Dyson
- Institut des Sciences et Ingénierie Chimiques
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- CH-1015 Lausanne
- Switzerland
| | - Stefano Zacchini
- Dipartimento di Chimica Industriale “Toso Montanari”
- Università di Bologna
- I-40136 Bologna
- Italy
| | - Silvia Schoch
- Dipartimento di Chimica e Chimica Industriale
- Università di Pisa
- I-56124 Pisa
- Italy
| | - Guido Pampaloni
- Dipartimento di Chimica e Chimica Industriale
- Università di Pisa
- I-56124 Pisa
- Italy
| | - Fabio Marchetti
- Dipartimento di Chimica e Chimica Industriale
- Università di Pisa
- I-56124 Pisa
- Italy
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4
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Bai L, Gao C, Liu Q, Yu C, Zhang Z, Cai L, Yang B, Qian Y, Yang J, Liao X. Research progress in modern structure of platinum complexes. Eur J Med Chem 2017; 140:349-382. [PMID: 28985575 DOI: 10.1016/j.ejmech.2017.09.034] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 07/18/2017] [Accepted: 09/18/2017] [Indexed: 10/18/2022]
Abstract
Since the antitumor activity of cisplatin was discovered in 1967 by Rosenberg, platinum-based anticancer drugs have played an important role in chemotherapy in clinic. Nevertheless, platinum anticancer drugs also have caused severe side effects and cross drug resistance which limited their applications. Therefore, a significant amount of efforts have been devoted to developing new platinum-based anticancer agents with equal or higher antitumor activity but lower toxicity. Until now, a large number of platinum-based complexes have been prepared and extensively investigated in vitro and in vivo. Among them, some platinum-based complexes revealing excellent anticancer activity showed the potential to be developed as novel type of anticancer agents. In this account, we present such platinum-based anticancer complexes which owning various types of ligands, such as, amine carrier ligands, leaving groups, reactive molecule, steric hindrance groups, non-covalently binding platinum (II) complexes, Platinum(IV) complexes and polynuclear platinum complexes. Overall, platinum-based anticancer complexes reported recently years upon modern structure are emphasized.
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Affiliation(s)
- Linkui Bai
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Chuanzhu Gao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China.
| | - Qinghua Liu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Congtao Yu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Zhuxin Zhang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Linxiang Cai
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Bo Yang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Yunxu Qian
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Jian Yang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
| | - Xiali Liao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China
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5
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Posadas I, Alonso-Moreno C, Bravo I, Carrillo-Hermosilla F, Garzón A, Villaseca N, López-Solera I, Albaladejo J, Ceña V. Synthesis, characterization, DNA interactions and antiproliferative activity on glioblastoma of iminopyridine platinum(II) chelate complexes. J Inorg Biochem 2017; 168:46-54. [DOI: 10.1016/j.jinorgbio.2016.11.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 11/22/2016] [Accepted: 11/30/2016] [Indexed: 12/21/2022]
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6
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Tabrizi L, Chiniforoshan H. Designing new iridium(iii) arene complexes of naphthoquinone derivatives as anticancer agents: a structure–activity relationship study. Dalton Trans 2017; 46:2339-2349. [DOI: 10.1039/c6dt04339a] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A series of iridium(iii) arene complexes of naphthoquinone derivatives have been synthesized and investigated for their suitability as potential anticancer drugs.
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Affiliation(s)
- Leila Tabrizi
- School of Chemistry
- National University of Ireland
- Galway
- Ireland
- Department of Chemistry
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7
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Tabrizi L. The discovery of half-sandwich iridium complexes containing lidocaine and (pyren-1-yl)ethynyl derivatives of phenylcyanamide ligands for photodynamic therapy. Dalton Trans 2017; 46:7242-7252. [DOI: 10.1039/c7dt01091e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The new design of two cyclopentadienyl iridium(iii) complexes with (pyren-1-yl)ethynyl derivatives of phenylcyanamide and lidocaine ligands, have been studied for photodynamic therapy.
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Affiliation(s)
- Leila Tabrizi
- School of Chemistry
- National University of Ireland
- Galway
- Ireland
- Department of Chemistry
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8
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Pracharova J, Saltarella T, Radosova Muchova T, Scintilla S, Novohradsky V, Novakova O, Intini FP, Pacifico C, Natile G, Ilik P, Brabec V, Kasparkova J. Novel Antitumor Cisplatin and Transplatin Derivatives Containing 1-Methyl-7-Azaindole: Synthesis, Characterization, and Cellular Responses. J Med Chem 2014; 58:847-59. [DOI: 10.1021/jm501420k] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Jitka Pracharova
- Department
of Biophysics, Centre of the Region Hana for Biotechnological and
Agricultural Research, Palacky University, Slechtitelu 11, 783 41 Olomouc, Czech Republic
| | - Teresa Saltarella
- Department
of Chemistry, University of Bari “Aldo Moro”, 70125 Bari, Italy
| | - Tereza Radosova Muchova
- Department
of Biophysics, Centre of the Region Hana for Biotechnological and
Agricultural Research, Palacky University, Slechtitelu 11, 783 41 Olomouc, Czech Republic
| | - Simone Scintilla
- Department
of Chemistry, University of Bari “Aldo Moro”, 70125 Bari, Italy
| | - Vojtech Novohradsky
- Institute
of Biophysics, Academy of Sciences of the Czech Republic, v.v.i.,
Kralovopolska 135, CZ-61265 Brno, Czech Republic
- Department
of Biophysics, Faculty of Science, Palacky University in Olomouc, Slechtitelu 11, 78371 Olomouc, Czech Republic
| | - Olga Novakova
- Institute
of Biophysics, Academy of Sciences of the Czech Republic, v.v.i.,
Kralovopolska 135, CZ-61265 Brno, Czech Republic
| | | | - Concetta Pacifico
- Department
of Chemistry, University of Bari “Aldo Moro”, 70125 Bari, Italy
| | - Giovanni Natile
- Department
of Chemistry, University of Bari “Aldo Moro”, 70125 Bari, Italy
| | - Petr Ilik
- Department
of Biophysics, Centre of the Region Hana for Biotechnological and
Agricultural Research, Palacky University, Slechtitelu 11, 783 41 Olomouc, Czech Republic
| | - Viktor Brabec
- Department
of Biophysics, Faculty of Science, Palacky University in Olomouc, Slechtitelu 11, 78371 Olomouc, Czech Republic
| | - Jana Kasparkova
- Institute
of Biophysics, Academy of Sciences of the Czech Republic, v.v.i.,
Kralovopolska 135, CZ-61265 Brno, Czech Republic
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9
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Novakova O, Liskova B, Vystrcilova J, Suchankova T, Vrana O, Starha P, Travnicek Z, Brabec V. Conformation and recognition of DNA damaged by antitumor cis-dichlorido platinum(II) complex of CDK inhibitor bohemine. Eur J Med Chem 2014; 78:54-64. [PMID: 24675180 DOI: 10.1016/j.ejmech.2014.03.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 02/20/2014] [Accepted: 03/14/2014] [Indexed: 12/18/2022]
Abstract
A substitution of the ammine ligands of cisplatin, cis-[Pt(NH3)2Cl2], for cyclin dependent kinase (CDK) inhibitor bohemine (boh), [2-(3-hydroxypropylamino)-6-benzylamino-9-isopropylpurine], results in a compound, cis-[Pt(boh)2Cl2] (C1), with the unique anticancer profile which may be associated with some features of the damaged DNA and/or its cellular processing (Travnicek Z et al. (2003) J Inorg Biochem94, 307-316; Liskova B (2012) Chem Res Toxicol25, 500-509). A combination of biochemical and molecular biology techniques was used to establish mechanistic differences between cisplatin and C1 with respect to the DNA damage they produce and their interactions with critical DNA-binding proteins, DNA-processing enzymes and glutathione. The results show that replacement of the NH3 groups in cisplatin by bohemine modulates some aspects of the mechanism of action of C1. More specifically, the results of the present work are consistent with the thesis that, in comparison with cisplatin, effects of other factors, such as: (i) slower rate of initial binding of C1 to DNA; (ii) the lower efficiency of C1 to form bifunctional adducts; (iii) the reduced bend of longitudinal DNA axis induced by the major 1,2-GG intrastrand cross-link of C1; (iv) the reduced affinity of HMG domain proteins to the major adduct of C1; (v) the enhanced efficiency of the DNA adducts of C1 to block DNA polymerization and to inhibit transcription activity of human RNA pol II and RNA transcription; (vi) slower rate of the reaction of C1 with glutathione, may partially contribute to the unique activity of C1.
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Affiliation(s)
- Olga Novakova
- Institute of Biophysics, Academy of Sciences of The Czech Republic, v.v.i., CZ-61265 Brno, Czech Republic
| | - Barbora Liskova
- Institute of Biophysics, Academy of Sciences of The Czech Republic, v.v.i., CZ-61265 Brno, Czech Republic
| | - Jana Vystrcilova
- Institute of Biophysics, Academy of Sciences of The Czech Republic, v.v.i., CZ-61265 Brno, Czech Republic
| | - Tereza Suchankova
- Institute of Biophysics, Academy of Sciences of The Czech Republic, v.v.i., CZ-61265 Brno, Czech Republic
| | - Oldrich Vrana
- Institute of Biophysics, Academy of Sciences of The Czech Republic, v.v.i., CZ-61265 Brno, Czech Republic
| | - Pavel Starha
- Regional Centre of Advanced Technologies and Materials, Department of Inorganic Chemistry, Faculty of Science, Palacky University, 17. listopadu 12, CZ-77146 Olomouc, Czech Republic
| | - Zdenek Travnicek
- Regional Centre of Advanced Technologies and Materials, Department of Inorganic Chemistry, Faculty of Science, Palacky University, 17. listopadu 12, CZ-77146 Olomouc, Czech Republic
| | - Viktor Brabec
- Institute of Biophysics, Academy of Sciences of The Czech Republic, v.v.i., CZ-61265 Brno, Czech Republic.
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10
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Pracharova J, Zerzankova L, Stepankova J, Novakova O, Farrer NJ, Sadler PJ, Brabec V, Kasparkova J. Interactions of DNA with a new platinum(IV) azide dipyridine complex activated by UVA and visible light: relationship to toxicity in tumor cells. Chem Res Toxicol 2012; 25:1099-111. [PMID: 22420335 DOI: 10.1021/tx300057y] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The Pt(IV) diazido complex trans,trans,trans-[Pt(N(3))(2)(OH)(2)(pyridine)(2)] (1) is unreactive in the dark but is cytotoxic when photoactivated by UVA and visible light. We have shown that 1 when photoactivated accumulates in tumor cells and binds strongly to nuclear DNA under conditions in which it is toxic to tumor cells. The nature of the DNA adducts, including conformational alterations, induced by photoactivated 1 are distinctly different from those produced in DNA by conventional cisplatin or transplatin. In addition, the observation that major DNA adducts of photoactivated 1 are able to efficiently stall RNA polymerase II more efficiently than cisplatin suggests that transcription inhibition may contribute to the cytotoxicity levels observed for photoactivated 1. Hence, DNA adducts of 1 could trigger a number of downstream cellular effects different from those triggered in cancer cells by DNA adducts of cisplatin. This might lead to the therapeutic effects that could radically improve chemotherapy by platinum complexes. The findings of the present work help to explain the different cytotoxic effects of photoactivated 1 and conventional cisplatin and thereby provide new insights into mechanisms associated with the antitumor effects of platinum complexes photoactivated by UVA and visible light.
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Affiliation(s)
- Jitka Pracharova
- Department of Biophysics, Faculty of Science, Palacky University, 17. Listopadu 12, Olomouc, Czech Republic
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11
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Malina J, Novakova O, Vojtiskova M, Natile G, Brabec V. Conformation of DNA GG intrastrand cross-link of antitumor oxaliplatin and its enantiomeric analog. Biophys J 2007; 93:3950-62. [PMID: 17704160 PMCID: PMC2084227 DOI: 10.1529/biophysj.107.116996] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Downstream processes that discriminate between DNA adducts of a third generation platinum antitumor drug oxaliplatin and conventional cisplatin are believed to be responsible for the differences in their biological effects. These different biological effects are explained by the ability of oxaliplatin to form DNA adducts more efficient in their biological effects. In this work conformation, recognition by HMG domain protein and DNA polymerization across the major 1,2-GG intrastrand cross-link formed by cisplatin and oxaliplatin in three sequence contexts were compared with the aid of biophysical and biochemical methods. The following major differences in the properties of the cross-links of oxaliplatin and cisplatin were found: i), the formation of the cross-link by oxaliplatin is more deleterious energetically in all three sequence contexts; ii), the cross-link of oxaliplatin bends DNA slightly but systematically less in all sequence contexts tested; iii), the affinity of HMG domain protein to the cross-link of oxaliplatin is considerably lower independent of the sequence context; and iv), the Klenow fragment of DNA polymerase I pauses considerably more at the cross-link of oxaliplatin in all sequence contexts tested. We have also demonstrated that the chirality at the carrier ligand of oxaliplatin can affect its biological effects.
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Affiliation(s)
- Jaroslav Malina
- Institute of Biophysics, Academy of Sciences of the Czech Republic, CZ-61265 Brno, Czech Republic
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12
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13
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Kaspárková J, Nováková O, Vrána O, Intini F, Natile G, Brabec V. Molecular Aspects of Antitumor Effects of a New Platinum(IV) Drug. Mol Pharmacol 2006; 70:1708-19. [PMID: 16896071 DOI: 10.1124/mol.106.027730] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The new platinum(IV) complex cis,trans,cis-[PtCl(2)(CH(3)COO)(2)-(NH(3))(1-adamantylamine)] [adamplatin(IV)] seems promising for the perspective application in therapy of corresponding tumors. It is therefore of great interest to understand details of mechanisms underlying its biological efficacy. Cellular uptake of the drug, alterations in the target DNA induced by platinum drugs along with processing of platinum-induced damage to DNA and drug inactivation by sulfur-containing compounds belong to major pharmacological factors affecting antitumor effects of platinum compounds. We examined in the present work the significance of these factors in the mechanism of antitumor effects of adamplatin(IV) and compared the results with those of the parallel studies performed with "conventional" cisplatin. The results show that deactivation of adamplatin(IV) by sulfur-containing compounds (such as glutathione or metallothioneins) is likely to play a less significant role in the mechanism of resistance of tumor cells to adamplatin(IV) in contrast to the role of these reactions in the effects of cisplatin. Moreover, the treatment of tumor cells with adamplatin(IV) does not result in DNA modifications that would be markedly different from those produced by cisplatin. In contrast, the effects of other factors, such as enhanced accumulation of the drug in cells, strong inhibition of DNA polymerization by these adducts, lowered DNA repair, and DNA-protein cross-linking are different from the effects of these factors in the mechanism underlying activity of cisplatin. Hence, the differences between effects of adamplatin(IV) and cisplatin observed in the present work on molecular level may help understand the unique activity of adamplatin(IV).
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Affiliation(s)
- Jana Kaspárková
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, CZ-61265 Brno, Czech Republic
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14
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Williams KM, Chapman DJ, Massey SR, Haare C. Interaction of N-acetylmethionine with a non-C2-symmetrical platinum diamine complex. J Inorg Biochem 2005; 99:2119-26. [PMID: 16129491 DOI: 10.1016/j.jinorgbio.2005.07.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2005] [Revised: 07/13/2005] [Accepted: 07/15/2005] [Indexed: 11/17/2022]
Abstract
The reaction of N-acetylmethionine (N-AcMet) with the complex [Pt(Et(2)en)(D(2)O)(2)](2+) (Et(2)en=N,N-diethylethylenediamine) was studied by NMR spectroscopy and molecular mechanics calculations. Complexes containing two methionine residues coordinated to the platinum atom were calculated to be relatively high in energy unless the bulk of the methionine residues was directed away from the diethyl group of the Et(2)en ligand. In contrast, sulfur-oxygen chelates were found to be relatively free of steric clashes. Experimentally, two sets of NMR resonances were observed when [Pt(Et(2)en)(D(2)O)(2)](2+) was reacted with N-AcMet; variable temperature experiments indicated intermediate chemical exchange between the two sets of resonances. NMR studies indicated that the resonances corresponded to [Pt(Et(2)en)(N-AcMet-S,O)](+) complexes with the sulfur atom trans to the diethyl group of the Et(2)en ligand. No product with the sulfur atom cis to the diethyl group was observed experimentally even though molecular mechanics calculations suggested that such forms have few steric clashes. The NMR results suggested that the chemical exchange was a result of sulfur chirality inversion. In early stages of the reaction, a [Pt(Et(2)en)(N-AcMet-S)(D(2)O)](+) complex was observed, indicating that coordination of the oxygen to form the chelate is relatively slow.
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Affiliation(s)
- Kevin M Williams
- Department of Chemistry, Western Kentucky University, 1 Big Red Way, Bowling Green, KY 42101, USA.
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15
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Malina J, Vojtiskova M, Brabec V, Diakos CI, Hambley TW. DNA adducts of the enantiomers of the Pt(II) complexes of the ahaz ligand (ahaz=3-aminohexahydroazepine) and recognition of these adducts by HMG domain proteins. Biochem Biophys Res Commun 2005; 332:1034-41. [PMID: 15922304 DOI: 10.1016/j.bbrc.2005.05.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2005] [Accepted: 05/10/2005] [Indexed: 11/22/2022]
Abstract
The bending, unwinding, and structural changes in DNA caused by the binding of each of the enantiomers of the platinum(II) complexes of the ahaz ligand (R- and S-[PtCl(2)(ahaz)], ahaz=3-aminohexahydroazepine) have been studied using 20-23 bp oligonucleotides containing TGGT and CGGA-binding sites as has the recognition of the adducts by HMG domain proteins. The domain A of HMGB1 (HMGB1a protein) binds to the adduct formed by the R enantiomer at the CGGA sequence with a similar high affinity as it does to the adduct of antitumor cisplatin, and to the adduct formed by the S enantiomer with a slightly lower affinity. In contrast, HMGB1a binds much more weakly to the ahaz adducts than to the cisplatin adducts formed at the TGGT sequence, with the binding to the adduct formed by the R enantiomer being weakest. Each enantiomer and cisplatin cause unwinding of both sequences that is in the narrow range, 19-22 degrees. There are modest but significant differences in the degree of bending induced, with the S enantiomer causing the least bending, cisplatin intermediate, and the R enantiomer the most. Molecular modeling of the {Pt(ahaz)}/GG adducts in 8-bp models reveals significant differences in the local distortion at the GG-binding sites depending on the flanking bases and shows that interactions between the thymine methyl groups and the ahaz ligand are likely to inhibit bending of the TGGT sequence.
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Affiliation(s)
- Jaroslav Malina
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, CZ-61265 Brno, Czech Republic
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