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Evaluation of Rhenium and Technetium-99m Complexes Bearing Quinazoline Derivatives as Potential EGFR Agents. Molecules 2023; 28:molecules28041786. [PMID: 36838773 PMCID: PMC9960821 DOI: 10.3390/molecules28041786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 02/07/2023] [Accepted: 02/10/2023] [Indexed: 02/16/2023] Open
Abstract
Τhe Epidermal Growth Factor Receptor tyrosine kinase inhibitor (EGFR-TKI) 6-amino-4-[(3-bromophenyl) amino]quinazoline was derivatized with 6-bromohexanoyl-chloride and coupled with the tridentate chelating agents N-(2-pyridylmethyl) aminoethyl acetic acid (PAMA) and L(+)-cysteine bearing the donor atom set NNO and SNO, respectively. The rhenium precursors ReBr(CO)5 and fac-[NEt4]2[ReBr3(CO)3] were used for the preparation of the Re complexes fac-[Re(NNO)(CO)3] (5a) and fac-[Re(SNO)(CO)3] (7a) which were characterized by NMR and IR spectroscopies. Subsequently, the new potential EGFR inhibitors were labeled with the fac-[99mTc(CO)3]+ core in high yield and radiochemical purity (>90%) by ligand exchange reaction using the fac-[99mTc][Tc(OH2)3(CO)3]+ precursor. The radiolabeled complexes were characterized by comparative HPLC analysis with the analogous rhenium (Re) complexes as references. In vitro studies in the A431 cell lines showed that both ligands and Re complexes inhibit A431 cell growth. Complex 5a demonstrated the highest potency (IC50 = 8.85 ± 2.62 μM) and was further assessed for its capacity to inhibit EGFR autophosphorylation, presenting an IC50 value of 26.11 nM. Biodistribution studies of the 99mTc complexes in healthy mice showed high in vivo stability for both complexes and fast blood and soft tissue clearance with excretion occurring via the hepatobiliary system.
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Sidorenko GV, Miroslavov AE, Tyupina MY. Technetium(I) carbonyl complexes for nuclear medicine: Coordination-chemical aspect. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2022.214911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ranasinghe K, Marzilli PA, Pakhomova S, Marzilli LG. New fac-[ReI(CO)3(Ltri)]Y complexes of linear N,N′,N′′-tridentate ligands (Ltri) with terminal imidazolyl or pyridyl ring (N and N′′) and central tertiary sulfonamide (N′) N-donors. Effects of size and substituents of the terminal N-donor rings and the rarely found direct sulfonamide N to metal bond. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2021.120781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Exploring the synthesis and characterization of fac-Re(CO)3L complexes using diethylenetriamine derivative functionalized at the central nitrogen. Inorganica Chim Acta 2021. [DOI: 10.1016/j.ica.2021.120291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Darshani T, Fronczek FR, Priyadarshani VV, Samarakoon SR, Perera IC, Perera T. Synthesis and characterization of novel naphthalene-derivatized tridentate ligands and their net neutral rhenium tricarbonyl complexes and cytotoxic effects on non-small cell lung cancer cells of interest. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114652] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Darshani T, Thushara N, Weerasuriya P, Fronczek FR, Perera IC, Perera T. Fluorescent di-(2-picolyl)amine based drug-like ligands and their Re(CO)3 complexes towards biological applications. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114592] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Lodhi NA, Park JY, Hong MK, Kim YJ, Lee YS, Cheon GJ, Jeong JM. Development of 99mTc-labeled trivalent isonitrile radiotracer for folate receptor imaging. Bioorg Med Chem 2019; 27:1925-1931. [PMID: 30992201 DOI: 10.1016/j.bmc.2019.04.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 04/04/2019] [Accepted: 04/06/2019] [Indexed: 10/27/2022]
Abstract
Folate receptors (FR) are frequently overexpressed in a wide variety of human cancers. The aim of this study was to develop a trivalent 99mTc(CO)3-labeled folate radiotracer containing isonitrile (CN-R) as the coordinating ligand for FR target imaging. [99mTc]Tc-10 was HPLC purified (>98% chemical purity) and evaluated in vitro and in vivo as a potential agent for targeting FR-positive KB cells. [99mTc]Tc-10 is a hydrophilic compound with partition coefficient of -2.90 ± 0.13 that showed high binding affinity (0.04 ± 0.002 nM) in vitro. High accumulation and retention of [99mTc]Tc-10 (5.32 ± 2.99% ID/g) was observed in mice with KB tumors at 4 h after injection through the tail vein, which was significantly inhibited by co-injection of free folic acid (FA). SPECT (single photon emission tomography)/CT results were in accordance with biodistribution data at all time points.
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Affiliation(s)
- Nadeem Ahmed Lodhi
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Isotope Production Division, Pakistan Institute of Nuclear Science & Technology (PINSTECH), P. O, Nilore, Islamabad, Pakistan
| | - Ji Yong Park
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Mi Kyung Hong
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Young Joo Kim
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Yun-Sang Lee
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Gi Jeong Cheon
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jae Min Jeong
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, Republic of Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea.
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Lipowska M, Klenc J, Taylor AT, Marzilli LG. fac- 99mTc/Re-tricarbonyl complexes with tridentate aminocarboxyphosphonate ligands: suitability of the phosphonate group in chelate ligand design of new imaging agents. Inorganica Chim Acta 2019; 486:529-537. [PMID: 30804606 PMCID: PMC6385875 DOI: 10.1016/j.ica.2018.11.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Ligands that coordinate via dianionic phosphonate groups have not been widely utilized in radiopharmaceuticals. N-(phosphonomethyl)iminodiacetic acid (1, PMIDA) and N-(phosphonomethyl)glycine (2, PMG) were investigated as new chelators for the 99mTc/Re-tricarbonyl "core" (fac-M(CO)3, M = 99mTc, Re) present in a major class of radiopharmaceuticals. fac-M(CO)3(PMIDA) and fac-M(CO)3(PMG) complexes were studied by HPLC and 1H/13C/31P NMR methods for M = Re (Re-1 and Re-2) and by HPLC for M = 99mTc ( 99m Tc-1 and 99m Tc-2). Re-1 and 99m Tc-1 complexes exhibit a similar pH-dependent equilibrium between geometric linkage isomers (M-1a and M-1b). However, only one isomer exists for M-2 under all conditions. Structural characterization by X-ray crystallography reveals the presence of a bond between a phosphonate oxygen and the Re(I) center in fac-Re(CO)3(PMG) (Re-2). Detailed comparisons of NMR data for Re-2 conclusively demonstrate that the phosphonate group is coordinated in Re-1b (isomer favored at high pH) but not in Re-1a, which has a dangling N-(phosphonomethyl) group. To our knowledge, Re-1b and Re-2 and their 99mTc analogs are the first well-documented examples of complexes with these metal-tricarbonyl cores having a dianionic phosphonate group directly coordinated in a fac-M(CO)3-O-P grouping. Pharmacokinetic studies using Sprague-Dawley rats reveal that 99m Tc-2 is a robust tracer. Hence, phosphonate groups should be considered in designing 99mTc and 186/188Re radiopharmaceuticals, including agents with bioactive moieties attached to dangling carboxylate or phosphonate groups.
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Affiliation(s)
- Malgorzata Lipowska
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia 30322, United States
| | - Jeffrey Klenc
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia 30322, United States
| | - Andrew T. Taylor
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia 30322, United States
| | - Luigi G. Marzilli
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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Turnbull WL, Yu L, Murrell E, Milne M, Charron CL, Luyt LG. A dual modality99mTc/Re(i)-labelled T140 analogue for imaging of CXCR4 expression. Org Biomol Chem 2019; 17:598-608. [DOI: 10.1039/c8ob01947a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A T140-derived peptide conjugated with a naphthalimide fluorophore/chelator was coordinated to rhenium or technetium-99m to image CXCR4 expression by fluorescence microscopy or SPECT imaging.
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Affiliation(s)
| | - Lihai Yu
- London Regional Cancer Program
- Lawson Health Research Institute
- London
- Canada
| | - Emily Murrell
- Department of Chemistry
- University of Western Ontario
- London
- Canada
| | - Mark Milne
- London Regional Cancer Program
- Lawson Health Research Institute
- London
- Canada
| | - Carlie L. Charron
- London Regional Cancer Program
- Lawson Health Research Institute
- London
- Canada
| | - Leonard G. Luyt
- Department of Chemistry
- University of Western Ontario
- London
- Canada
- London Regional Cancer Program
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Nazir S, Anwar J, Munawar MA, Qazi JI, Best SP, Cheah M, Muhammad Yaseen. Metal complexation induces antibiotic activity in S-ethyl-l-cysteine sulfoxide. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2018.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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11
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Mašković JM, Hatzidimitriou A, Damjanović A, Stanojković TP, Trifunović SR, Geronikaki AA, Papagiannopoulou D. Synthesis, characterization and biological evaluation of Pd(ii), Cu(ii), Re(i) and 99mTc(i) thiazole-based complexes. MEDCHEMCOMM 2018; 9:831-842. [PMID: 30108972 DOI: 10.1039/c8md00067k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 04/11/2018] [Indexed: 11/21/2022]
Abstract
A new thiazole-containing multidentate ligand 2-((2-phenylthiazol-4-yl)methylthio)ethanamine, L, was synthesized and used to prepare new complexes of the formula PdIILCl2 (Pd-L), CuIIL2Cl2 (Cu-L) and fac-[Re/99mTcI(CO)3(L)]+ (Re/99mTc-L). The ligand L and the metal complexes were characterized spectroscopically. Furthermore, the structures of Re-L and Cu-L were elucidated by X-ray crystallography. Ligand L acts as a bidentate (Nth, S) chelator in Pd-L, as a bidentate (N, S) chelator in Cu-L and as a tridentate (Nth, S, N) chelator in Re-L. The radiotracer 99mTc-L was synthesized in high yield and characterised by HPLC comparison with the Re-L analog. The synthesized compounds were evaluated for their anti-inflammatory and cytotoxic properties. The compounds exhibited low anti-inflammatory activity with Pd-L showing the highest activity among them. The cytotoxic activity of the ligand and the complexes against several human cancer cell lines (cervical adenocarcinoma HeLa, colorectal adenocarcinoma LS-174T, lung adenocarcinoma A549, breast adenocarcinoma MDA-MB-231 and normal human lung fibroblast cell line MRC-5) was examined using the MTT assay. The complex Cu-L exhibited the highest cytotoxicity and the complex Pd-L showed the best tumor selectivity. The changes in the cell cycle phase distribution were determined by flow cytometry and it was found that ligand L shows the highest apoptotic activity. The biodistribution studies of 99mTc-L in mice showed fast tissue clearance. Of all the thiazole-containing compounds, the palladium complex appears to be more promising for future efforts.
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Affiliation(s)
- Jelena M Mašković
- Faculty of Agronomy , University of Kragujevac , Cara Dušana 34 , 32 000 Čačak , Republic of Serbia
| | - Antonios Hatzidimitriou
- Laboratory of Inorganic Chemistry , School of Chemistry , Faculty of Sciences , Aristotle University of Thessaloniki , 54124 , Thessaloniki , Greece
| | - Ana Damjanović
- Institute for Oncology and Radiology of Serbia , Pasterova 14 , 11000 Belgrade , Serbia
| | - Tatjana P Stanojković
- Institute for Oncology and Radiology of Serbia , Pasterova 14 , 11000 Belgrade , Serbia
| | - Srećko R Trifunović
- Department of Chemistry , Faculty of Science , University of Kragujevac , Radoja Domanovića 12 , 34 000 Kragujevac , Republic of Serbia
| | - Athina A Geronikaki
- Department of Pharmaceutical Chemistry , School of Pharmacy , Faculty of Health Sciences , Aristotle University of Thessaloniki , 54124 University Campus , Thessaloniki , Greece . ; ; Tel: +30 2310 998680
| | - Dionysia Papagiannopoulou
- Department of Pharmaceutical Chemistry , School of Pharmacy , Faculty of Health Sciences , Aristotle University of Thessaloniki , 54124 University Campus , Thessaloniki , Greece . ; ; Tel: +30 2310 998680
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Lipowska M, Jarkas N, Voll RJ, Nye JA, Klenc J, Goodman MM, Taylor AT. Re(CO) 3([ 18F]FEDA), a novel 18F PET renal tracer: Radiosynthesis and preclinical evaluation. Nucl Med Biol 2017; 58:42-50. [PMID: 29367095 DOI: 10.1016/j.nucmedbio.2017.12.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 12/05/2017] [Accepted: 12/11/2017] [Indexed: 11/15/2022]
Abstract
INTRODUCTION Our previous work demonstrated that the 99mTc renal tracer, 99mTc(CO)3(FEDA) (99mTc-1), has a rapid clearance comparable in rats to that of 131I-OIH, the radioactive gold standard for the measurement of effective renal plasma flow. The uncharged fluoroethyl pendant group of 99mTc-1 provides a route to the synthesis of a structurally analogous rhenium-tricarbonyl 18F renal imaging agent, Re(CO)3([18F]FEDA) (18F-1). Our goal was to develop an efficient one-step method for the preparation of 18F-1 and to compare its pharmacokinetic properties with those of 131I-OIH in rats. METHODS 18F-1 was prepared by the nucleophilic 18F-fluorination of its tosyl precursor. The labeled compound was isolated by HPLC and subsequently evaluated in Sprague-Dawley rats using 131I-OIH as an internal control and by dynamic PET/CT imaging. Plasma protein binding (PPB) and erythrocyte uptake (RCB) were determined and the urine was analyzed for metabolites. RESULTS 18F-1 was efficiently prepared as a single species with high radiochemical purity (>99%) and it displayed high radiochemical stability in vitro and in vivo. PPB was 87% and RCB was 21%. Biodistribution studies confirmed rapid renal extraction and high specificity for renal excretion, comparable to that of 131I-OIH, with minimal hepatic/gastrointestinal elimination. The activity in the urine, as a percentage of 131I-OIH, was 92% and 95% at 10 and 60 min, respectively. All other organs (heart, spleen, lungs) showed a negligible tracer uptake (<0.4% ID). Dynamic microPET/CT imaging demonstrated rapid transit of 18F-1 through the kidneys and into the bladder; there was no demonstrable activity in bone verifying the absence of free [18F]fluoride. CONCLUSIONS 18F-1 exhibited a high specificity for the kidney, rapid renal excretion comparable to that of 131I-OIH and high in vivo radiochemical stability. Not only is 18F-1 a promising PET renal tracer, but it provides a route to the development of a pair of analogous 18F/99mTc renal imaging agents with almost identical structures and comparable pharmacokinetic properties. These promising in vivo results warrant subsequent evaluation in humans.
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Affiliation(s)
- Malgorzata Lipowska
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, NE, Atlanta, GA 30322, USA.
| | - Nashwa Jarkas
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, NE, Atlanta, GA 30322, USA
| | - Ronald J Voll
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, NE, Atlanta, GA 30322, USA; Center for Systems Imaging, Emory University, Wesley Woods Health Center, 1841 Clifton Road, NE, Atlanta, GA 30329, USA
| | - Jonathon A Nye
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, NE, Atlanta, GA 30322, USA; Center for Systems Imaging, Emory University, Wesley Woods Health Center, 1841 Clifton Road, NE, Atlanta, GA 30329, USA
| | - Jeffrey Klenc
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, NE, Atlanta, GA 30322, USA
| | - Mark M Goodman
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, NE, Atlanta, GA 30322, USA; Center for Systems Imaging, Emory University, Wesley Woods Health Center, 1841 Clifton Road, NE, Atlanta, GA 30329, USA
| | - Andrew T Taylor
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, NE, Atlanta, GA 30322, USA
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Papagiannopoulou D. Technetium-99m radiochemistry for pharmaceutical applications. J Labelled Comp Radiopharm 2017; 60:502-520. [PMID: 28618064 DOI: 10.1002/jlcr.3531] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 06/08/2017] [Accepted: 06/08/2017] [Indexed: 12/14/2022]
Abstract
Technetium-99m (99m Tc) is a widely used radionuclide, and the development of 99m Tc imaging agents continues to be in demand. This overview discusses basic principles of 99m Tc radiopharmaceutical preparation and design and focuses on the 99m Tc radiochemistry relevant to its pharmaceutical applications. The 99m Tc complexes are described based on the most typical examples in each category, keeping up with the state-of-the-art in the field. In addition, the main current strategies to develop targeted 99m Tc radiopharmaceuticals are summarized.
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Affiliation(s)
- Dionysia Papagiannopoulou
- Department of Pharmaceutical Chemistry, School of Pharmacy, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
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Hayes TR, Bottorff SC, Slocumb WS, Barnes CL, Clark AE, Benny PD. Influence of bidentate ligand donor types on the formation and stability in 2 + 1 fac-[M I(CO) 3] + (M = Re, 99mTc) complexes. Dalton Trans 2017; 46:1134-1144. [PMID: 28045466 DOI: 10.1039/c6dt04282a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In the last two decades, a number of chelate strategies have been proposed for the fac-[MI(CO)3]+ (M = Re, 99mTc) core in radiopharmaceutical applications. However, the development of new ligands/complexes with improved function and in vivo performance has been limited in recent years. Expanding on our previous studies using the 2 + 1 labeling strategy, a series of bidentate ligands (neutral vs. anionic) containing an aromatic amine in combination with monodentate pyridine analogs or imidazole were explored to determine the influence of the bidentate and monodentate ligands on the formation and stability of the respective complexes. The 2 + 1 complexes with Re and 99mTc were synthesized in two steps and characterized by standard radio/chemical methods. X-ray characterization and density functional theory analysis of the Re 2 + 1 complexes with the complete bidentate series with 4-dimethylaminopyridine were conducted, indicating enhanced ligand binding energies of the neutral over anionic ligands. In the 99mTc studies, anionic bidentate ligands had significantly higher formation yields of the 2 + 1 product, but neutral ligands appear to have increased stability in an amino acid challenge assay. Both bidentate series exhibited improved stability by increasing the basicity of the pyridine ligands.
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Affiliation(s)
- Thomas R Hayes
- Washington State University, Department of Chemistry, Pullman, WA 99164, USA.
| | - Shalina C Bottorff
- Washington State University, Department of Chemistry, Pullman, WA 99164, USA.
| | - Winston S Slocumb
- Washington State University, Department of Chemistry, Pullman, WA 99164, USA.
| | - Charles L Barnes
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA
| | - Aurora E Clark
- Washington State University, Department of Chemistry, Pullman, WA 99164, USA.
| | - Paul D Benny
- Washington State University, Department of Chemistry, Pullman, WA 99164, USA.
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Lipowska M, Klenc J, Jarkas N, Marzilli LG, Taylor AT. Monoanionic 99mTc-tricarbonyl-aminopolycarboxylate complexes with uncharged pendant groups: Radiosynthesis and evaluation as potential renal tubular tracers. Nucl Med Biol 2016; 47:48-55. [PMID: 28110124 DOI: 10.1016/j.nucmedbio.2016.12.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 12/19/2016] [Accepted: 12/21/2016] [Indexed: 11/15/2022]
Abstract
INTRODUCTION 99mTc(CO)3-nitrilotriacetic acid, 99mTc(CO)3(NTA), is a new renal tubular agent with pharmacokinetic properties comparable to those of 131I-OIH but the clearance of 99mTc(CO)3(NTA) and 131I-OIH is still less than the clearance of PAH, the gold standard for the measurement of effective renal plasma flow. At physiological pH, dianionic 99mTc(CO)3(NTA) has a mononegative inner metal-coordination sphere and a mononegative uncoordinated carboxyl group. To evaluate alternate synthetic approaches, we assessed the importance of an uncoordinated carboxyl group, long considered essential for tubular transport, by evaluating the pharmacokinetics of three analogs with the 99mTc(CO)3(NTA) metal-coordination sphere but with uncharged pendant groups. METHODS 99mTc(CO)3 complexes with N-(2-acetamido)iminodiacetic acid (ADA), N-(2-hydroxyethyl)iminodiacetic acid (HDA) and N-(fluoroethyl)iminodiacetic acid (FEDA) were prepared using a tricarbonyl kit and isolated by HPLC. The pharmacokinetics were evaluated in Sprague-Dawley rats, with 131I-OIH as an internal control; urine was analyzed for metabolites. Plasma protein binding and erythrocyte uptake were determined from the 10min blood samples. Re(CO)3(FEDA), the analog of 99mTc(CO)3(FEDA), was prepared and characterized. RESULTS 99mTc(CO)3(ADA), 99mTc(CO)3(HDA) and 99mTc(CO)3(FEDA) were efficiently prepared as a single species with high radiochemical purities (>99%). These new monoanionic 99mTc(CO)3 tracers with uncharged dangling groups all showed rapid blood clearance and high specificity for renal excretion. Activity in the urine, as a percent of 131I-OIH at 10 and 60min, was 96% and 99% for ADA, 96% and 100% for HDA, and 100% and 99% for FEDA, respectively. Each new tracer was excreted unchanged in the urine. The Re(CO)3(FEDA) structure adds compelling evidence that such 99mTc(CO)3(NTA) analogs have metal-coordination spheres identical to that of 99mTc(CO)3(NTA). CONCLUSIONS New tracers lacking the negatively charged pendant carboxyl group previously thought to be essential for rapid renal extraction, 99mTc(CO)3(ADA), 99mTc(CO)3(HDA) and 99mTc(CO)3(FEDA), exhibit pharmacokinetics in rats comparable to those of 99mTc(CO)3(NTA) and 131I-OIH. Furthermore, these encouraging results in rats warrant evaluation of this new tracer type in humans.
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Affiliation(s)
- Malgorzata Lipowska
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA.
| | - Jeffrey Klenc
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA
| | - Nashwa Jarkas
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA
| | - Luigi G Marzilli
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, USA
| | - Andrew T Taylor
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA
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Ranasinghe K, Handunnetti S, Perera IC, Perera T. Synthesis and characterization of novel rhenium(I) complexes towards potential biological imaging applications. Chem Cent J 2016; 10:71. [PMID: 27942267 PMCID: PMC5123207 DOI: 10.1186/s13065-016-0218-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 11/10/2016] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Re(I) tricarbonyl complexes exhibit immense potential as fluorescence imaging agents. However, only a handful of rhenium complexes have been utilized in biological imaging. The present study describes the synthesis of four novel rhenium complexes, their characterization and preliminary biological studies to assess their potential as biological imaging agents. RESULTS Four facial rhenium tricarbonyl complexes containing a pyridyl triazine core, (L1 = 5,5'(3-(2-pyridyl)-1,2,4-triazine-5,6-diyl)-bis-2-furansulfonic acid disodium salt and L2 = (3-(2- pyridyl)-5,6-diphenyl-1,2,4-triazine-4',4''-disulfonic acid sodium salt) have been synthesized by utililzing two different Re metal precursors, Re(CO)5Br and [Re(CO)3(H2O)3]OTf in an organic solvent mixture and water, respectively. The rhenium complexes [Re(CO)3(H2O)L1]+ (1), Re(CO)3L1Br (2), [Re(CO)3(H2O)L2]+ (3), and Re(CO)3L2Br (4), were obtained in 70-85% yield and characterized by 1H NMR, IR, UV, and luminescence spectroscopy. In both H2O and acetonitrile, complexes display a weak absorption band in the visible region which can be assigned to a metal to ligand charge transfer excitation and fluorescent emission lying in the 650-710 nm range. Cytotoxicity assays of complexes 1, 3, and 4 were carried out for rat peritoneal cells. Both plant cells (Allium cepa bulb cells) and rat peritoneal cells were stained using the maximum non-toxic concentration levels of the compounds, 20.00 mg ml-1 for 1 and 3 and 5.00 mg ml-1 for 4 to observe under the epifluorescence microscope. In both cell lines, compound concentrated specifically in the nuclei region. Hence, nuclei showed red fluorescence upon excitation at 550 nm. CONCLUSIONS Four novel rhenium complexes have been synthesized and characterized. Remarkable enhancement of fluorescence upon binding with cells and visible range excitability demonstrates the possibility of using the new complexes in biological applications.Graphical abstractMicrograph of rat peritoneal cells incubated with novel rhenium complex under epifluorescence microscope.
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Affiliation(s)
- Kokila Ranasinghe
- Department of Chemistry, University of Sri Jayewardenepura, Nugegoda, Sri Lanka
| | - Shiroma Handunnetti
- Institute of Biochemistry, Molecular Biology and Biotechnology, University of Colombo, Colombo, Sri Lanka
| | - Inoka C. Perera
- Department of Zoology and Environmental Sciences, University of Colombo, Colombo, Sri Lanka
| | - Theshini Perera
- Department of Chemistry, University of Sri Jayewardenepura, Nugegoda, Sri Lanka
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Synthesis, Characterization, and Biological Studies of a Piperidinyl Appended Dipicolylamine Ligand and Its Rhenium Tricarbonyl Complex as Potential Therapeutic Agents for Human Breast Cancer. Bioinorg Chem Appl 2016; 2016:2675937. [PMID: 27847444 PMCID: PMC5101407 DOI: 10.1155/2016/2675937] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Accepted: 09/06/2016] [Indexed: 11/18/2022] Open
Abstract
A novel ligand bearing a central piperidinyl sulfonamide group, N(SO2pip)dpa, and its corresponding Re tricarbonyl complex, [Re(CO)3(N(SO2pip)dpa)]+, have been synthesized in good yield. The methylene CH2 signal seen as a singlet (4.54 ppm) in a 1H NMR spectrum of the ligand in DMSO-d6 appears as two doublets (5.39, 5.01 ppm) in a spectrum of the [Re(CO)3(N(SO2pip)dpa)]+ complex and confirms the presence of magnetically nonequivalent protons upon coordination to Re. Structural results revealed that the Re-N bond lengths fall within the normal range establishing coordination of ligand to metal. The presence of intraligand π → π⁎ and n → π⁎ transitions is indicated by the absorption peaks around 200-250 nm in UV-visible spectra. Absorption peaks in UV-visible spectra around 300 nm for metal complexes were identified as MLCT transitions. The S-N stretch observed as a strong peak at 923 cm-1 for N(SO2pip)dpa appeared at a shorter frequency, at 830 cm-1 in an FTIR spectrum of the [Re(CO)3(N(SO2pip)dpa)]+. The intense fluorescence displayed by the N(SO2pip)dpa ligand has quenched upon coordination to Re. Relatively low IC50 values given by human breast cancer cells, MCF-7, (N(SO2pip)dpa = 139 μM, [Re(CO)3(N(SO2pip)dpa)]+ = 360 μM) indicate that N(SO2pip)dpa and [Re(CO)3(N(SO2pip)dpa)]+ are promising novel compounds that can be further investigated on their usage as potential anticancer agents.
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18
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Piletska KO, Domasevitch KV, Shtemenko AV. Crystal structure of fac-aquatricarbonyl[(S)-valin-ato-κ(2) N,O]-rhenium(I). Acta Crystallogr E Crystallogr Commun 2016; 72:590-2. [PMID: 27375894 PMCID: PMC4910339 DOI: 10.1107/s2056989016005235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 03/28/2016] [Indexed: 11/10/2022]
Abstract
In the mol-ecule of the title compound, [Re(C5H10NO2)(CO)3(H2O)], the Re(I) atom adopts a distorted octa-hedral coordination sphere defined by one aqua and three carbonyl ligands as well as one amino N and one carboxyl-ate O atom of the chelating valinate anion. The carbonyl ligands are arranged in a fac-configuration around the Re(I) ion. In the crystal, an intricate hydrogen-bonding system under participation of two O-H, two N-H and one C-H donor groups and the carboxyl-ate and carbonyl O atoms as acceptor groups contribute to the formation of a three-dimensional supra-molecular network.
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Affiliation(s)
- Kseniia O. Piletska
- Department of Inorganic Chemistry, Ukrainian State University of Chemical Technology, Gagarin Ave. 8, Dnipropetrovsk 49005, Ukraine
| | - Kostiantyn V. Domasevitch
- Inorganic Chemistry Department, National Taras Shevchenko University of Kyiv, Volodymyrska Street 64/13, Kyiv 01601, Ukraine
| | - Alexander V. Shtemenko
- Department of Inorganic Chemistry, Ukrainian State University of Chemical Technology, Gagarin Ave. 8, Dnipropetrovsk 49005, Ukraine
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Synthesis and evaluation of fac-[99mTc/Re(CO)3]+ complexes with a new (N,S,N) bifunctional chelating agent: The first example of a fac-[Re(CO)3(N,S,N-sst2-ANT)] complex bearing a somatostatin receptor antagonist peptide. J Organomet Chem 2016. [DOI: 10.1016/j.jorganchem.2016.01.005] [Citation(s) in RCA: 14] [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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20
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Kasten BB, Ma X, Cheng K, Bu L, Slocumb WS, Hayes TR, Trabue S, Cheng Z, Benny PD. Isothiocyanate-Functionalized Bifunctional Chelates and fac-[M(I)(CO)3](+) (M = Re, (99m)Tc) Complexes for Targeting uPAR in Prostate Cancer. Bioconjug Chem 2015; 27:130-42. [PMID: 26603218 DOI: 10.1021/acs.bioconjchem.5b00531] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Developing new strategies to rapidly incorporate the fac-[M(I)(CO)3](+) (M = Re, (99m)Tc) core into biological targeting vectors in radiopharmaceuticals continues to expand as molecules become more complex and as efforts to minimize nonspecific binding increase. This work examines a novel isothiocyanate-functionalized bifunctional chelate based on 2,2'-dipicolylamine (DPA) specifically designed for complexing the fac-[M(I)(CO)3](+) core. Two strategies (postlabeling and prelabeling) were explored using the isothiocyanate-functionalized DPA to determine the effectiveness of assembly on the overall yield and purity of the complex with amine containing biomolecules. A model amino acid (lysine) examined (1) amine conjugation of isothiocyanate-functionalized DPA followed by complexation with fac-[M(I)(CO)3](+) (postlabeling) and (2) complexation of fac-[M(I)(CO)3](+) with isothiocyanate-functionalized DPA followed by amine conjugation (prelabeling). Conducted with stable Re and radioactive (99m)Tc analogs, both strategies formed the product in good to excellent yields under macroscopic and radiotracer concentrations. A synthetic peptide (AE105) which targets an emerging biomarker in CaP prognosis, urokinase-type plasminogen activator receptor (uPAR), was also explored using the isothiocyanate-functionalized DPA strategy. In vitro PC-3 (uPAR+) cell uptake assays with the (99m)Tc-labeled peptide (8a) showed 4.2 ± 0.5% uptake at 4 h. In a murine model bearing PC-3 tumor xenografts, in vivo biodistribution of 8a led to favorable tumor uptake (3.7 ± 0.7% ID/g) at 4 h p.i. with relatively low accumulation (<2% ID/g) in normal organs not associated with normal peptide excretion. These results illustrate the promise of the isothiocyanate-functionalized approach for labeling amine containing biological targeting vectors with fac-[M(I)(CO)3](+).
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Affiliation(s)
| | - Xiaowei Ma
- Department of Nuclear Medicine, Xijing Hospital, Fourth Military Medical University , Xi'an, Shaanxi 710032, China.,Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Bio-X Program and Canary Center at Stanford for Cancer Early Detection, Stanford University , Stanford, California 94305, United States
| | - Kai Cheng
- Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Bio-X Program and Canary Center at Stanford for Cancer Early Detection, Stanford University , Stanford, California 94305, United States
| | - Lihong Bu
- Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Bio-X Program and Canary Center at Stanford for Cancer Early Detection, Stanford University , Stanford, California 94305, United States
| | | | | | - Steven Trabue
- United States Department of Agriculture, National Soil Tilth Laboratory , Ames, Iowa 50011, United States
| | - Zhen Cheng
- Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Bio-X Program and Canary Center at Stanford for Cancer Early Detection, Stanford University , Stanford, California 94305, United States
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21
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Synthesis, characterization and biological evaluation of (99m)Tc/Re-tricarbonyl quinolone complexes. J Inorg Biochem 2015; 160:94-105. [PMID: 26795497 DOI: 10.1016/j.jinorgbio.2015.12.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 11/26/2015] [Accepted: 12/16/2015] [Indexed: 11/24/2022]
Abstract
New rhenium(I) tricarbonyl complexes with the quinolone antimicrobial agents oxolinic acid (Hoxo) and enrofloxacin (Herx) and containing methanol, triphenylphosphine (PPh3) or imidazole (im) as unidentate co-ligands, were synthesized and characterized. The crystal structure of complex [Re(CO)3(oxo)(PPh3)]∙0.5MeOH was determined by X-ray crystallography. The deprotonated quinolone ligands are bound bidentately to rhenium(I) ion through the pyridone oxygen and a carboxylate oxygen. The binding of the rhenium complexes to calf-thymus DNA (CT DNA) was monitored by UV spectroscopy, viscosity measurements and competitive studies with ethidium bromide; intercalation was suggested as the most possible mode and the DNA-binding constants of the complexes were calculated. The rhenium complex [Re(CO)3(erx)(im)] was assayed for its topoisomerase IIα inhibition activity and was found to be active at 100μM concentration. The interaction of the rhenium complexes with human or bovine serum albumin was investigated by fluorescence emission spectroscopy (through the tryptophan quenching) and the corresponding binding constants were determined. The tracer complex [(99m)Tc(CO)3(erx)(im)] was synthesized and identified by comparative HPLC analysis with the rhenium analog. The (99m)Tc complex was found to be stable in solution. Upon injection in healthy mice, fast tissue clearance of the (99m)Tc complex was observed, while both renal and hepatobiliary excretion took place. Preliminary studies in human K-562 erythroleukemia cells showed cellular uptake of the (99m)Tc tracer with distribution primarily in the cytoplasm and the mitochondria and less in the nucleus. These preliminary results indicate that the quinolone (99m)Tc/Re complexes show promise to be further evaluated as imaging or therapeutic agents.
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22
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North AJ, Hayne DJ, Schieber C, Price K, White AR, Crouch PJ, Rigopoulos A, O'Keefe GJ, Tochon-Danguy H, Scott AM, White JM, Ackermann U, Donnelly PS. Toward hypoxia-selective rhenium and technetium tricarbonyl complexes. Inorg Chem 2015; 54:9594-610. [PMID: 26375592 DOI: 10.1021/acs.inorgchem.5b01691] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
With the aim of preparing hypoxia-selective imaging and therapeutic agents, technetium(I) and rhenium(I) tricarbonyl complexes with pyridylhydrazone, dipyridylamine, and pyridylaminocarboxylate ligands containing nitrobenzyl or nitroimidazole functional groups have been prepared. The rhenium tricarbonyl complexes were synthesized with short reaction times using microwave irradiation. Rhenium tricarbonyl complexes with deprotonated p-nitrophenyl pyridylhydrazone ligands are luminescent, and this has been used to track their uptake in HeLa cells using confocal fluorescent microscopy. Selected rhenium tricarbonyl complexes displayed higher uptake in hypoxic cells when compared to normoxic cells. A (99m)Tc tricarbonyl complex with a dipyridylamine ligand bearing a nitroimidazole functional group is stable in human serum and was shown to localize in a human renal cell carcinoma (RCC; SK-RC-52) tumor in a mouse.
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Affiliation(s)
| | | | | | | | | | | | - Angela Rigopoulos
- Ludwig Institute for Cancer Research , Melbourne-Austin Branch, 145 Studley Road, Heidelberg, Victoria 3084, Australia
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23
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Hayes TR, Powell AS, Barnes CL, Benny PD. Synthesis and stability of 2+1 complexes of N,N-diethylbenzoylthiourea with [MI(CO)3]+ (M = Re, 99mTc). J COORD CHEM 2015. [DOI: 10.1080/00958972.2015.1071801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Thomas R. Hayes
- Department of Chemistry, Washington State University, Pullman, WA, USA
| | - Ashton S. Powell
- Department of Chemistry, Washington State University, Pullman, WA, USA
| | | | - Paul D. Benny
- Department of Chemistry, Washington State University, Pullman, WA, USA
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24
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Klenc J, Lipowska M, Abhayawardhana PL, Taylor AT, Marzilli LG. Structure and Properties of fac-[Re(I)(CO)3(NTA)](2-) (NTA(3-) = Trianion of Nitrilotriacetic Acid) and fac-[Re(I)(CO)3(L)](n-) Analogues Useful for Assessing the Excellent Renal Clearance of the fac-[(99m)Tc(I)(CO)3(NTA)](2-) Diagnostic Renal Agent. Inorg Chem 2015; 54:6281-90. [PMID: 26068141 PMCID: PMC4863976 DOI: 10.1021/acs.inorgchem.5b00584] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We previously identified two new agents based on the [(99m)Tc(V)O](3+) core with renal clearances in human volunteers 30% higher than that of the widely used clinical tracer (99m)Tc-MAG3 (MAG3(5-) = penta-anion of mercaptoacetyltriglycine). However, renal agents with even higher clearances are needed. More recently, we changed our focus from the [(99m)Tc(V)O](3+) core to the discovery of superior tracers based on the fac-[(99m)Tc(I)(CO)3](+) core. Compared to (99m)Tc-MAG3, fac-[(99m)Tc(I)(CO)3(NTA)](2-) (NTA(3-) = trianion of nitrilotriacetic acid) holds great promise by virtue of its efficient renal clearance via tubular secretion and the absence of hepatobiliary elimination, even in patients with severely reduced renal function. We report here NMR, molecular (X-ray) structure, and solution data on fac-[Re(I)(CO)3(NTA)](2-) with a -CH2CO2(-) dangling monoanionic chain and on two fac-[Re(I)(CO)3(L)](-) analogues with either a -CH2CONH2 or a -CH2CH2OH dangling neutral chain. In these three fac-[Re(I)(CO)3(L)](n-) complexes, the fac-[Re(I)(CO)3(N(CH2CO2)2)](-) moiety is structurally similar and has similar electronic properties (as assessed by NMR data). In reported and ongoing studies, the two fac-[(99m)Tc(I)(CO)3(L)](-) analogues with these neutral dangling chains were found to have pharmacokinetic properties very similar to those of fac-[(99m)Tc(I)(CO)3(NTA)](2-). Therefore, we reach the unexpected conclusion that in fac-[(99m)Tc(I)(CO)3(L)](n-) agents, renal clearance is affected much more than anticipated by features of the core plus the chelate rings (the [(99m)Tc(I)(CO)3(N(CH2CO2)2)](-) moiety) than by the presence of a negatively charged dangling carboxylate chain.
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Affiliation(s)
- Jeffrey Klenc
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia 30322, United States
| | - Malgorzata Lipowska
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia 30322, United States
| | | | - Andrew T. Taylor
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia 30322, United States
| | - Luigi G. Marzilli
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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25
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Klenc J, Lipowska M, Taylor AT. Identification of lead compounds for (99m)Tc and (18)F GPR91 radiotracers. Bioorg Med Chem Lett 2015; 25:2335-9. [PMID: 25908514 PMCID: PMC4433761 DOI: 10.1016/j.bmcl.2015.04.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 04/01/2015] [Accepted: 04/08/2015] [Indexed: 10/23/2022]
Abstract
To develop the first radiotracer targeting GPR91, a cell membrane-bound receptor that modulates the cellular response to hyperglycemia and hypoxia, we designed and prepared a small series of compounds based on a published series of 1,8-naphthyridines with high affinity to GPR91. Our approach provides a mechanism to incorporate radioactive atoms ((99m)Tc and (18)F) into the GPR91 pharmacophore as the final synthetic step. Pharmacological assays confirmed lead compounds for (99m)Tc and (18)F GPR91 radiotracers within the series.
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Affiliation(s)
- Jeffrey Klenc
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA 30322, USA.
| | - Malgorzata Lipowska
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA 30322, USA
| | - Andrew T Taylor
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA 30322, USA
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26
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Hayes TR, Lyon PA, Barnes CL, Trabue S, Benny PD. Influence of functionalized pyridine ligands on the radio/chemical behavior of [M(I)(CO)3](+) (M = Re and (99m)Tc) 2 + 1 complexes. Inorg Chem 2015; 54:1528-34. [PMID: 25590985 DOI: 10.1021/ic502520x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
While a number of chelate strategies have been developed for the organometallic precursor fac-[M(I)(OH2)3(CO)3](+) (M = Re, (99m)Tc), a unique challenge has been to improve the overall function and performance of these complexes for in vivo and in vitro applications. Since its discovery, fac-[M(I)(OH2)3(CO)3](+) has served as an essential scaffold for the development of new targeted (99m)Tc based radiopharmaceuticals due to its labile aquo ligands. However, the lipophilic nature of the fac-[M(I)(CO)3](+) core can influence the in vivo pharmacokinetics and biodistribution of the complexes. In an effort to understand and improve this behavior, monosubstituted pyridine ligands were used to assess the impact of donor nitrogen basicity on binding strength and stability of fac-[M(I)(CO)3](+) in a 2 + 1 labeling strategy. A series of Re and (99m)Tc complexes were synthesized with picolinic acid as a bidentate ligand and 4-substituted pyridine ligands. These complexes were designed to probe the effect of pKa from the monodentate pyridine ligand both at the macro scale and radiochemical concentrations. Comparison of X-ray structural data and radiochemical solution experiments clearly indicate an increase in overall yield and stability as pyridine basicity increased.
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Affiliation(s)
- Thomas R Hayes
- Department of Chemistry, Washington State University , Pullman, Washington 99164, United States
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27
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Lecina J, Palacios Ò, Atrian S, Capdevila M, Suades J. Rhenium and technetium tricarbonyl, {M(CO)3} (+) (M = Tc, Re), binding to mammalian metallothioneins: new insights into chemical and radiopharmaceutical implications. J Biol Inorg Chem 2014; 20:465-74. [PMID: 25511253 DOI: 10.1007/s00775-014-1226-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 11/29/2014] [Indexed: 11/25/2022]
Abstract
This paper deals with the binding of the four mammalian metallothioneins (MTs) to the organometallic metal fragment {fac-M(CO)3}(+) (M = (99)Tc, Re), which is highly promising for the preparation of second-generation radiopharmaceuticals. The study of the transmetallation reaction between zinc and rhenium in Zn7-MT1 by means of UV-vis and CD spectroscopy demonstrated the incorporation of the {fac-Re(CO)3}(+) fragment to the MTs. This reaction should be performed at 70 °C to accelerate the reaction rate, a result that is consistent with the reported reactivity of the rhenium fragment. ESI-TOF MS demonstrated the formation of mixed-metal species as Zn6,{Re(CO)3}-MT, Zn6,{Re(CO)3}2-MT, and Zn5,{Re(CO)3}3-MT, as well as the different reactivity of the four MT isoforms. Hence, Zn-MT3 showed the highest reactivity, in agreement with its high Cu-thionein character, whereas Zn-MT2 exhibited the lowest reactivity, in line with its high Zn-thionein character. The reactivity of the Zn-loaded forms of MT1 and MT4 is intermediate between those of MT3 and MT2. The study of the binding of the {fac-(99)Tc(CO)3}(+) fragment to MTs showed a significant and very interesting different reactivity in relation to rhenium. The transmetallation reaction is much more effective with technetium than with rhenium and significant amounts of mixed Zn x ,{(99)Tc(CO)3} y -MT species were formed with the four MT isoforms whereas only MT3 rendered similar amounts of rhenium derivatives. The results obtained in this study support the possible use of technetium for labelling mammalian metallothioneins and also for possible radiopharmaceutical applications.
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Affiliation(s)
- Joan Lecina
- Departament de Química, Facultat de Ciències, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Barcelona, Spain
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Hickey JL, Simpson EJ, Hou J, Luyt LG. An Integrated Imaging Probe Design: The Synthesis of99mTc/Re-Containing Macrocyclic Peptide Scaffolds. Chemistry 2014; 21:568-78. [DOI: 10.1002/chem.201404774] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Indexed: 11/11/2022]
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29
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Yoe F, Flores-Alamo M, Morales F, Escudero R, Cortes-Hernández H, Castro M, Barba-Behrens N. Structural, magnetic and theoretical study of mononuclear nickel(II) and cobalt(II) compounds of a benzimidazole thiobutanoic acid derivative. Inorganica Chim Acta 2014. [DOI: 10.1016/j.ica.2014.07.025] [Citation(s) in RCA: 4] [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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30
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Chen X, Guo K, Li F, Zhou L, Qiao H. Synthesis and properties of Zn2+/Cd2+-directed self-assembled metallo-supramolecular polymers based on 1,4-diketo-pyrrolo[3,4-c]pyrrole (DPP) derivatives. RSC Adv 2014. [DOI: 10.1039/c4ra10685g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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31
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Lewis NA, Marzilli PA, Fronczek FR, Marzilli LG. Models for B12-conjugated radiopharmaceuticals. Cobaloxime binding to new fac-[Re(CO)3(Me2bipyridine)(amidine)]BF4 complexes having an exposed pyridyl nitrogen. Inorg Chem 2014; 53:11096-107. [PMID: 25285912 DOI: 10.1021/ic5016675] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
New mononuclear amidine complexes, fac-[Re(CO)3(Me2bipy)(HNC(CH3)(pyppz))]BF4 [(4,4'-Me2bipy (1), 5,5'-Me2bipy (2), and 6,6'-Me2bipy (3)] (bipy = 2,2'-bipyridine), were synthesized by treating the parent fac-[Re(I)(CO)3(Me2bipy)(CH3CN)]BF4 complex with the C2-symmetrical amine 1-(4-pyridyl)piperazine (pyppzH). The axial amidine ligand has an exposed, highly basic pyridyl nitrogen. The reaction of complexes 1-3 with a B12 model, (py)Co(DH)2Cl (DH = monoanion of dimethylglyoxime), in CH2Cl2 yielded the respective dinuclear complexes, namely, fac-[Re(CO)3(Me2bipy)(μ-(HNC(CH3)(pyppz)))Co(DH)2Cl]BF4 [(4,4'-Me2bipy (4), 5,5'-Me2bipy (5), and 6,6'-Me2bipy (6)]. (1)H NMR spectroscopic analysis of all compounds and single-crystal X-ray crystallographic data for 2, 3, 5, and 6 established that the amidine had only the E configuration in both the solid and solution states and that the pyridyl group is bound to Co in 4-6. Comparison of the NMR spectra of 1-3 with spectra of 4-6 reveals an unusually large "wrong-way" upfield shift for the pyridyl H2/6 signal for 4-6. The wrong-way H2/6 shift of (4-Xpy)Co(DH)2Cl (4-Xpy = 4-substituted pyridine) complexes increased with increasing basicity of the 4-Xpy derivative, a finding attributed to the influence of the magnetic anisotropy of the cobalt center on the shifts of the (1)H NMR signals of the pyridyl protons closest to Co. Our method of employing a coordinate bond for conjugating the fac-[Re(I)(CO)3] core to a vitamin B12 model could be extended to natural B12 derivatives. Because B12 compounds are known to accumulate in cancer cells, such an approach is a very attractive method for the development of (99m)Tc and (186/188)Re radiopharmaceuticals for targeted tumor imaging and therapy.
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Affiliation(s)
- Nerissa A Lewis
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
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32
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Lecina J, Cortés P, Llagostera M, Piera C, Suades J. New rhenium complexes with ciprofloxacin as useful models for understanding the properties of [99mTc]-ciprofloxacin radiopharmaceutical. Bioorg Med Chem 2014; 22:3262-9. [DOI: 10.1016/j.bmc.2014.04.058] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 04/28/2014] [Indexed: 11/15/2022]
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Synthesis of (Pyridin-2-YL)Hydrazone Rhenium(I) Tricarbonyl Complexes that Exhibit pH-Sensitive Fluorescence. Chem Heterocycl Compd (N Y) 2014. [DOI: 10.1007/s10593-014-1469-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Giglio J, Dematteis S, Fernández S, Cerecetto H, Rey A. Synthesis and evaluation of a new99mTc(I)-tricarbonyl complex bearing the 5-nitroimidazol-1-yl moiety as potential hypoxia imaging agent. J Labelled Comp Radiopharm 2014; 57:403-9. [PMID: 24692093 DOI: 10.1002/jlcr.3195] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 12/09/2013] [Accepted: 02/09/2014] [Indexed: 11/08/2022]
Affiliation(s)
- J. Giglio
- Cátedra de Radioquímica, Facultad de Química; Universidad de la República; Montevideo Uruguay
| | - S. Dematteis
- Cátedra de Inmunología, Facultad de Química; Universidad de la República; Montevideo Uruguay
| | - S. Fernández
- Cátedra de Radioquímica, Facultad de Química; Universidad de la República; Montevideo Uruguay
| | - H. Cerecetto
- Área de Radiofarmacia y Radioquímica-CIN, Facultad de Ciencias; Universidad de la República; Montevideo Uruguay
| | - A. Rey
- Cátedra de Radioquímica, Facultad de Química; Universidad de la República; Montevideo Uruguay
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35
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Kasten BB, Ma X, Liu H, Hayes TR, Barnes CL, Qi S, Cheng K, Bottorff SC, Slocumb WS, Wang J, Cheng Z, Benny PD. Clickable, hydrophilic ligand for fac-[M(I)(CO)3](+) (M = Re/(99m)Tc) applied in an S-functionalized α-MSH peptide. Bioconjug Chem 2014; 25:579-92. [PMID: 24568284 PMCID: PMC3983144 DOI: 10.1021/bc5000115] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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The copper(I)-catalyzed azide–alkyne
cycloaddition (CuAAC)
click reaction was used to incorporate alkyne-functionalized dipicolylamine
(DPA) ligands (1 and 3) for fac-[MI(CO)3]+ (M = Re/99mTc) complexation into an α-melanocyte stimulating hormone (α-MSH)
peptide analogue. A novel DPA ligand with carboxylate substitutions
on the pyridyl rings (3) was designed to increase the
hydrophilicity and to decrease in vivo hepatobiliary retention of fac-[99mTcI(CO)3]+ complexes used in single photon emission computed tomography (SPECT)
imaging studies with targeting biomolecules. The fac-[ReI(CO)3(3)] complex (4) was used for chemical characterization and X-ray crystal
analysis prior to radiolabeling studies between 3 and fac-[99mTcI(OH2)3(CO)3]+. The corresponding 99mTc
complex (4a) was obtained in high radiochemical yields,
was stable in vitro for 24 h during amino acid challenge and serum
stability assays, and showed increased hydrophilicity by log P analysis compared to an analogous complex with nonfunctionalized
pyridine rings (2a). An α-MSH peptide functionalized
with an azide was labeled with fac-[MI(CO)3]+ using both click, then chelate (CuAAC reaction with 1 or 3 followed by
metal complexation) and chelate, then click (metal
complexation of 1 and 3 followed by CuAAC
with the peptide) strategies to assess the effects of CuAAC conditions
on fac-[MI(CO)3]+ complexation within a peptide framework. The peptides from the click, then chelate strategy had different HPLC tR’s and in vitro stabilities compared
to those from the chelate, then click strategy, suggesting
nonspecific coordination of fac-[MI(CO)3]+ using this synthetic route. The fac-[MI(CO)3]+-complexed peptides from
the chelate, then click strategy showed >90% stability
during in vitro challenge conditions for 6 h, demonstrated high affinity
and specificity for the melanocortin 1 receptor (MC1R) in IC50 analyses, and led to moderately high uptake in B16F10 melanoma cells.
Log P analysis of the 99mTc-labeled peptides
confirmed the enhanced hydrophilicity of the peptide bearing the novel,
carboxylate-functionalized DPA chelate (10a′)
compared to the peptide with the unmodified DPA chelate (9a′). In vivo biodistribution analysis of 9a′ and 10a′ showed moderate tumor uptake in a B16F10 melanoma
xenograft mouse model with enhanced renal uptake and surprising intestinal
uptake for 10a′ compared to predominantly hepatic
accumulation for 9a′. These results, coupled with
the versatility of CuAAC, suggests this novel, hydrophilic chelate
can be incorporated into numerous biomolecules containing azides for
generating targeted fac-[MI(CO)3]+ complexes in future studies.
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Affiliation(s)
- Benjamin B Kasten
- Department of Chemistry, Washington State University , Pullman, Washington 99164, United States
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36
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Abhayawardhana PL, Marzilli PA, Fronczek FR, Marzilli LG. Complexes possessing rare "tertiary" sulfonamide nitrogen-to-metal bonds of normal length: fac-[Re(CO)3(N(SO2R)dien)]PF6 complexes with hydrophilic sulfonamide ligands. Inorg Chem 2014; 53:1144-55. [PMID: 24400928 PMCID: PMC4465231 DOI: 10.1021/ic4026987] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Tertiary sulfonamide nitrogen-to-metal bonds of normal length are very rare. We recently discovered such a bond in one class of fac-[Re(CO)3(N(SO2R)(CH2Z)2)](n) complexes (Z = 2-pyridyl) with N(SO2R)dpa ligands derived from di-(2-picolyl)amine (N(H)dpa). fac-[M(CO)3(N(SO2R)(CH2Z)2)](n) agents (M = (186/188)Re, (99m)Tc) could find use as radiopharmaceutical bioconjugates when R is a targeting moiety. However, the planar, electron-withdrawing 2-pyridyl groups of N(SO2R)dpa destabilize the ligand to base and create relatively rigid chelate rings, raising the possibility that the rare M-N(sulfonamide) bond is an artifact of a restricted geometry. Also, the hydrophobic 2-pyridyl groups could cause undesirable accumulation in the liver, limiting future use in radiopharmaceuticals. Our goal is to identify a robust, hydrophilic, and flexible N(CH2Z)2 chelate framework. New C2-symmetric ligands, N(SO2R)(CH2Z)2 with (Z = CH2NH2; R = Me, dmb, or tol), were prepared by treating N(H)dien(Boc)2, a protected diethylenetriamine (N(H)dien) derivative, with methanesulfonyl chloride (MeSO2Cl), 3,5-dimethylbenzenesulfonyl chloride (dmbSO2Cl), and 4-methylbenzenesulfonyl chloride (tolSO2Cl). Treatment of fac-[Re(CO)3(H2O)3](+) with these ligands, designated as N(SO2R)dien, afforded new fac-[Re(CO)3(N(SO2R)dien)]PF6 complexes. Comparing the fac-[Re(CO)3(N(SO2Me)dien)]PF6 and fac-[Re(CO)3(N(SO2Me)dpa)]PF6 complexes, we find that the Re(I)-N(sulfonamide) bonds are normal in length and statistically identical and that the methyl (13)C NMR signal has an unusually upfield shift compared to that in the free ligand. We attribute this unusual upfield shift to the fact that the sulfonamide N undergoes an sp(2)-to-sp(3) rehybridization upon coordination to Re(I) in both complexes. Thus, the sulfonamide N of N(SO2R)dien ligands is a good donor, even though the chelate rings are conformationally flexible. Addition of the strongly basic and potentially monodentate ligand, 4-dimethylaminopyridine, did not affect the fac-[Re(CO)3(N(SO2tol)dien)]PF6 complex, even after several weeks. This complex is also stable to heat in aqueous solution. These results indicate that N(SO2R)dien ligands form fac-[Re(CO)3(N(SO2R)dien)]PF6 complexes sufficiently robust to be utilized for radiopharmaceutical development.
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Affiliation(s)
| | - Patricia A. Marzilli
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Luigi G. Marzilli
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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37
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Maggioni D, Arosio P, Orsini F, Ferretti AM, Orlando T, Manfredi A, Ranucci E, Ferruti P, D'Alfonso G, Lascialfari A. Superparamagnetic iron oxide nanoparticles stabilized by a poly(amidoamine)-rhenium complex as potential theranostic probe. Dalton Trans 2013; 43:1172-83. [PMID: 24169854 DOI: 10.1039/c3dt52377b] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Three-component nanocomposites, constituted by a superparamagnetic iron oxide core coated with a polymeric surfactant bearing tightly bound Re(CO)3 moieties, were prepared and fully characterized. The water soluble and biocompatible surfactant was a linear poly(amidoamine) copolymer (PAA), containing cysteamine pendants in the minority part (ISA23SH), able to coordinate Re(CO)3 fragments. For the synthesis of the nanocomposites two methods were compared, involving either (i) peptization of bare magnetite nanoparticles by interaction with the preformed ISA23SH-Re(CO)3 complex, or (ii) "one-pot" synthesis of iron oxide nanoparticles in the presence of the ISA23SH copolymer, followed by complexation of Re to the SPIO@ISA23SH nanocomposite. Full characterization by TEM, DLS, TGA, SQUID, and relaxometry showed that the second method gave better results. The magnetic cores had a roundish shape, with low dispersion (mean diameter ca. 6 nm) and a tendency to form larger aggregates (detected both by TEM and DLS), arising from multiple interactions of the polymeric coils. Aggregation did not affect the stability of the nano-suspension, found to be stable for many months without precipitate formation. The SPIO@PAA-Re nanoparticles (NPs) showed superparamagnetic behaviour and nuclear relaxivities similar or superior to commercial MRI contrast agents (CAs), which make them promising as MRI "negative" CAs. The possibility to encapsulate (186/188)Re isotopes (γ and β emitters) gives these novel NPs the potential to behave as bimodal nanostructures devoted to theranostic applications.
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Affiliation(s)
- Daniela Maggioni
- Dipartimento di Chimica, Università degli Studi di Milano, Via Golgi 19, 20133, Milano, Italy.
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38
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Nayak DK, Halder KK, Baishya R, Sen T, Mitra P, Debnath MC. Tricarbonyltechnetium(I) and tricarbonylrhenium(I) complexes of amino acids: crystal and molecular structure of a novel cyclic dimeric Re(CO)3-amino acid complex comprised of the OON donor atom set of the tridentate ligand. Dalton Trans 2013; 42:13565-75. [PMID: 23900487 DOI: 10.1039/c3dt50928a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Radiolabeled complexes of monoamino polycarboxylic, polyamino monocarboxylic and thiol containing amino acid ligands were prepared from a fac-[(99m)Tc(CO)3(H2O)3](+) precursor.The overall radiochemical yield was 94-98%. The complexes exhibited substantial in vitro and in vivo stability. The corresponding Re(I) complexes of the ligands DAPA, Asp and CysH were prepared and characterized by means of IR, NMR, and MS spectroscopic studies, as well as X-ray crystallography (for those containing D,L-DAPA and D,L-Asp). The rhenium complexes have been structurally correlated with the technetium complexes by means of HPLC studies. The reaction of Re(CO)5Cl with D,L-Asp in presence of triethylamine led to the formation of a new class of cyclic dimeric complexes formed by the OON donor atom set of the tridentate ligands. The amino carboxylate ligand system formed well defined complexes with a fac-[M(CO)3(H2O)3](+) core and shows good promise in (99m)Tc(CO)3 tracer development.
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Affiliation(s)
- Dipak Kumar Nayak
- Nuclear Medicine Division, Indian Institute of Chemical Biology (CSIR), 4, Raja S. C. Mullick Road, Jadavpur, Kolkata-700 032, India
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39
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Perera T, Abhayawardhana P, Marzilli PA, Fronczek FR, Marzilli LG. Formation of a metal-to-nitrogen bond of normal length by a neutral sufonamide group within a tridentate ligand. A new approach to radiopharmaceutical bioconjugation. Inorg Chem 2013; 52:2412-21. [PMID: 23421481 PMCID: PMC4465213 DOI: 10.1021/ic302180t] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We demonstrate that a tertiary sulfonamide group, N(SO2R)R'2, can rehybridize to form a M-N bond of normal length even when the group is in a linear tridentate ligand, such as in the new tridentate N(SO2R)dpa ligands derived from di-(2-picolyl)amine (N(H)dpa). N(SO2R)dpa ligands were used to prepare fac-[Re(CO)3(N(SO2R)dpa)](PF6 or BF4) complexes. Structural characterization of the new complexes established that the tertiary sulfonamide nitrogen atom binds to Re with concomitant sp(2)-to-sp(3) rehybridization, facilitating facial coordination. The new fac-[Re(CO)3(N(SO2R)dpa)]X structures provide the only examples for any metal with the sulfonamide as part of a noncyclic linear tridentate ligand and with a normal metal-to-nitrogen(tertiary sulfonamide) bond length. Rare previous examples of such normal M-N bonds have been found only in more constrained situations, such as with tripodal tetradentate ligands. Our long-term objectives for the new tridentate N(SO2R)dpa ligands are to develop the fundamental chemistry relevant to the eventual use of the fac-[M(I)(CO)3](+) core (M = (99m)Tc, (186/188)Re) in imaging and therapy. The sulfonamide group uniquely contributes to two of our goals: expanding ways to conjugate the fac-[M(I)(CO)3](+) core to biological molecules and also developing new symmetrical tridentate ligands that can coordinate facially to this core. Tests of our conjugation method, conducted by linking the fac-[Re(I)(CO)3](+) core to a new tetraarylporphyrin (T(N(SO2C6H4)dpa)P) as well as to a dansyl (5-(dimethylamino)naphthalene-1-sulfonyl) group, demonstrate that large molecular fragments can be tethered via a coordinated tertiary sulfonamide linkage to this core.
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Affiliation(s)
- Theshini Perera
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
| | | | - Patricia A. Marzilli
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
| | - Luigi G. Marzilli
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
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40
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Bottorff SC, Moore AL, Wemple AR, Bučar DK, MacGillivray LR, Benny PD. pH-Controlled Coordination Mode Rearrangements of “Clickable” Huisgen-Based Multidentate Ligands with [MI(CO)3]+ (M = Re, 99mTc). Inorg Chem 2013; 52:2939-50. [DOI: 10.1021/ic302330u] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Shalina C. Bottorff
- Department
of Chemistry, Washington State University, P.O. Box 644630, Pullman, Washington 99164, United States
| | - Adam L. Moore
- Department
of Chemistry, Washington State University, P.O. Box 644630, Pullman, Washington 99164, United States
| | - Ariana R. Wemple
- Department
of Chemistry, Washington State University, P.O. Box 644630, Pullman, Washington 99164, United States
| | - Dejan-Krešimir Bučar
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United
States
| | | | - Paul D. Benny
- Department
of Chemistry, Washington State University, P.O. Box 644630, Pullman, Washington 99164, United States
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41
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Hayes TR, Lyon PA, Silva-Lopez E, Twamley B, Benny PD. Photo-initiated thiol-ene click reactions as a potential strategy for incorporation of [M(I)(CO)3]+ (M = Re, (99m)Tc) complexes. Inorg Chem 2013; 52:3259-67. [PMID: 23445468 DOI: 10.1021/ic302771f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Click reactions offer a rapid technique to covalently assemble two molecules. In radiopharmaceutical construction, these reactions can be utilized to combine a radioactive metal complex with a biological targeting molecule to yield a potent tool for imaging or therapy applications. The photo-initiated radical thiol-ene click reaction between a thiol and an alkene was examined for the incorporation of [M(I)(CO)3](+) (M = Re, (99m)Tc) systems for conjugating biologically active targeting molecules containing a thiol. In this strategy, a potent chelate system, 2,2'-dipicolylamine (DPA), for [M(I)(CO)3](+) was functionalized at the central amine with a terminal alkene linker that was explored with two synthetic approaches, click then chelate and chelate then click, to determine the flexibility and applicability of the thiol-ene click reaction to specifically incorporate ligand systems and metal complexes with a thiol containing molecule. In the click then chelate approach, the thiol-ene click reaction was carried out with the DPA chelate followed by complexation with [M(I)(CO)3](+). In the chelate then click approach, the alkene functionalized DPA chelate was first complexed with [M(I)(CO)3](+) followed by the conduction of the thiol-ene click reaction. Initial studies utilized benzyl mercaptan as a model thiol for both strategies to generate the identical product from either route to provide information on reactivity and product formation. DPA ligands functionalized with two unique linker systems (allyl and propyl allyl ether) were prepared to examine the effect of the proximity of the chelate or complex on the thiol-ene click reaction. Both the thiol-ene click and coordination reactions with Re, (99m)Tc were performed in moderate to high yields demonstrating the potential of the thiol-ene click reaction for [M(I)(CO)3](+) incorporation into thiol containing biomolecules.
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Affiliation(s)
- Thomas R Hayes
- Department of Chemistry, Washington State University, P.O. Box 644630, Pullman, Washington 99164, USA
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42
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Maggioni D, Fenili F, D’Alfonso L, Donghi D, Panigati M, Zanoni I, Marzi R, Manfredi A, Ferruti P, D’Alfonso G, Ranucci E. Luminescent Rhenium and Ruthenium Complexes of an Amphoteric Poly(amidoamine) Functionalized with 1,10-Phenanthroline. Inorg Chem 2012; 51:12776-88. [DOI: 10.1021/ic301616b] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Daniela Maggioni
- Dipartimento di
Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
| | - Fabio Fenili
- Dipartimento di
Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
| | - Laura D’Alfonso
- Dipartimento di
Fisica, Università di Milano Bicocca, Piazza della Scienza 3, 20126 Milano, Italy
| | - Daniela Donghi
- Dipartimento di
Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
| | - Monica Panigati
- Dipartimento di
Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
- Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM), via G. Giusti 9, 50121 Firenze, Italy
| | - Ivan Zanoni
- Dipartimento di Biotecnologie
e Bioscienze, Università di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy
| | - Roberta Marzi
- Dipartimento di Biotecnologie
e Bioscienze, Università di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy
| | - Amedea Manfredi
- Dipartimento di
Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
| | - Paolo Ferruti
- Dipartimento di
Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
- Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM), via G. Giusti 9, 50121 Firenze, Italy
| | - Giuseppe D’Alfonso
- Dipartimento di
Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
- Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM), via G. Giusti 9, 50121 Firenze, Italy
| | - Elisabetta Ranucci
- Dipartimento di
Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
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43
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Jiang H, Kasten BB, Liu H, Qi S, Liu Y, Tian M, Barnes CL, Zhang H, Cheng Z, Benny PD. Novel, cysteine-modified chelation strategy for the incorporation of [M(I)(CO)(3)](+) (M = Re, (99m)Tc) in an α-MSH peptide. Bioconjug Chem 2012; 23:2300-12. [PMID: 23110503 DOI: 10.1021/bc300509k] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Engineering peptide-based targeting agents with residues for site-specific and stable complexation of radionuclides is a highly desirable strategy for producing diagnostic and therapeutic agents for cancer and other diseases. In this report, a model N-S-N(Py) ligand (3) and a cysteine-derived α-melanocyte stimulating hormone (α-MSH) peptide (6) were used as novel demonstrations of a widely applicable chelation strategy for incorporation of the [M(I)(CO)(3)](+) (M = Re, (99m)Tc) core into peptide-based molecules for radiopharmaceutical applications. The structural details of the core ligand-metal complexes as model systems were demonstrated by full chemical characterization of fac-[Re(I)(CO)(3)(N,S,N(Py)-3)](+) (4) and comparative high-performance liquid chromatography (HPLC) analysis between 4 and [(99m)Tc(I)(CO)(3)(N,S,N(Py)-3)](+) (4a). The α-MSH analogue bearing the N-S-N(Py) chelate on a modified cysteine residue (6) was generated and complexed with [M(I)(CO)(3)](+) to confirm the chelation strategy's utility when applied in a peptide-based targeting agent. Characterization of the Re(I)(CO)(3)-6 peptide conjugate (7) confirmed the efficient incorporation of the metal center, and the (99m)Tc(I)(CO)(3)-6 analogue (7a) was explored as a potential single photon emission computed tomography (SPECT) compound for imaging the melanocortin 1 receptor (MC1R) in melanoma. Peptide 7a showed excellent radiolabeling yields and in vitro stability during amino acid challenge and serum stability assays. In vitro B16F10 melanoma cell uptake of 7a reached a modest value of 2.3 ± 0.08% of applied activity at 2 h at 37 °C, while this uptake was significantly reduced by coincubation with a nonlabeled α-MSH analogue, NAPamide (3.2 μM) (P < 0.05). In vivo SPECT/X-ray computed tomography (SPECT/CT) imaging and biodistribution of 7a were evaluated in a B16F10 melanoma xenografted mouse model. SPECT/CT imaging clearly visualized the tumor at 1 h post injection (p.i.) with high tumor-to-background contrast. Blocking studies with coinjected NAPamide (10 mg per kg of mouse body weight) confirmed the in vivo specificity of 7a for MC1R-positive tumors. Biodistribution results with 7a yielded a moderate tumor uptake of 1.20 ± 0.09 percentage of the injected radioactive dose per gram of tissue (% ID/g) at 1 h p.i. Relatively high uptake of 7a was also seen in the kidneys and liver at 1 h p.i. (6.55 ± 0.36% ID/g and 4.44 ± 0.17% ID/g, respectively), although reduced kidney uptake was seen at 4 h p.i. (3.20 ± 0.48% ID/g). These results demonstrate the utility of the novel [M(I)(CO)(3)](+) chelation strategy when applied in a targeting peptide.
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Affiliation(s)
- Han Jiang
- Department of Nuclear Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Institute of Nuclear Medicine and Molecular Imaging of Zhejiang University, Center of Excellence in Medical Molecular Imaging of Zhejiang State, Hangzhou, 310009, China
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44
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Klenc J, Lipowska M, Taylor AT, Marzilli LG. Synthesis and characterization of fac-Re(CO) 3-aspartic- N-monoacetic acid, a structural analogue of a potential new renal tracer, fac- 99mTc(CO) 3(ASMA). Eur J Inorg Chem 2012; 2012:10.1002/ejic.201200599. [PMID: 24273448 PMCID: PMC3835576 DOI: 10.1002/ejic.201200599] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Indexed: 11/09/2022]
Abstract
The reaction of an aminopolycarboxylate ligand, aspartic-N-monoacetic acid (ASMA), with [Re(CO)3(H2O)3]+ was examined. The tridentate coordination of ASMA to this ReI tricarbonyl precursor yielded fac-Re(CO)3(ASMA) as a mixture of diastereomers. The chemistry is analogous to that of the TcI tricarbonyl complex, which yields fac-99mTc(CO)3(ASMA) under similar conditions. The formation, structure, and isomerization of fac-Re(CO)3(ASMA) products were characterized by HPLC, 1H NMR spectroscopy, and X-ray crystallography. The two major fac-Re(CO)3(ASMA) diastereomeric products each have a linear ONO coordination mode with two adjacent five-membered chelate rings, but they differ in the endo or exo orientation of the uncoordinated acetate group, in agreement with expectations based on previous studies. Conditions have been identified for the expedient isomerization of fac-Re(CO)3(ASMA) to a mixture consisting primarily of one major product. Because different isomeric species typically have different pharmacokinetic characteristics, these conditions may provide for the practical isolation of a single 99mTc(CO)3(ASMA) species, thus allowing the isolation of the isomer that has optimal imaging and pharmacokinetic characteristics. This information will aid in the design of future 99mTc radiopharmaceuticals.
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Affiliation(s)
- Jeffrey Klenc
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Rd, Atlanta, GA 30322, USA
| | - Malgorzata Lipowska
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Rd, Atlanta, GA 30322, USA
| | - Andrew T. Taylor
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Rd, Atlanta, GA 30322, USA
| | - Luigi G. Marzilli
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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45
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Morais GR, Paulo A, Santos I. Organometallic Complexes for SPECT Imaging and/or Radionuclide Therapy. Organometallics 2012. [DOI: 10.1021/om300501d] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Goreti Ribeiro Morais
- Unidade de Ciências
Quı́micas e Radiofarmacêuticas, Instituto
Tecnológico e Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, Estrada Nacional
10, 2686-953, Sacavém, Portugal
| | - António Paulo
- Unidade de Ciências
Quı́micas e Radiofarmacêuticas, Instituto
Tecnológico e Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, Estrada Nacional
10, 2686-953, Sacavém, Portugal
| | - Isabel Santos
- Unidade de Ciências
Quı́micas e Radiofarmacêuticas, Instituto
Tecnológico e Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, Estrada Nacional
10, 2686-953, Sacavém, Portugal
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Lecina J, Carrer A, Álvarez-Larena A, Mazzi U, Melendez-Alafort L, Suades J. New Bioconjugated Rhenium Carbonyls by Transmetalation Reaction with Zinc Derivatives. Organometallics 2012. [DOI: 10.1021/om300394v] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- J. Lecina
- Departament de Quı́mica, Edifici
C, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - A. Carrer
- Department of Pharmaceutical Sciences, University of Padova, 35131 Padova,
Italy
| | - A. Álvarez-Larena
- X-ray Diffraction Service, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - U. Mazzi
- Department of Pharmaceutical Sciences, University of Padova, 35131 Padova,
Italy
| | | | - J. Suades
- Departament de Quı́mica, Edifici
C, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
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47
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Abhayawardhana P, Marzilli PA, Perera T, Fronczek FR, Marzilli LG. New monodentate amidine superbasic ligands with a single configuration in fac-[Re(CO)3(5,5'- or 6,6'-Me2bipyridine)(amidine)]BF4 complexes. Inorg Chem 2012; 51:7271-83. [PMID: 22691073 PMCID: PMC4059189 DOI: 10.1021/ic300625n] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Treatment of two precursors, fac-[Re(CO)(3)(L)(CH(3)CN)]BF(4) [L = 5,5'-dimethyl-2,2'-bipyridine (5,5'-Me(2)bipy) (1) and 6,6'-dimethyl-2,2'-bipyridine (6,6'-Me(2)bipy) (2)], with five C(2)-symmetrical saturated heterocyclic amines yielded 10 new amidine complexes, fac-[Re(CO)(3)(L)(HNC(CH(3))N(CH(2)CH(2))(2)Y)]BF(4) [Y = CH(2), (CH(2))(2), (CH(2))(3), NH, or O]. All 10 complexes possess the novel feature of having only one isomer (amidine E configuration), as established by crystallographic and (1)H NMR spectroscopic methods. We are confident that NMR signals of the other possible isomer (amidine Z configuration) would have been detected, if it were present. Isomers are readily detected in closely related amidine complexes because the double-bond character of the amidine C-N3 bond (N3 is bound to Re) leads to slow E to Z isomer interchange. The new fac-[Re(CO)(3)(L)(HNC(CH(3))N(CH(2)CH(2))(2)Y)]BF(4) complexes have C-N3 bonds with essentially identical double-bond character. However, the reason that the Z isomer is so unstable as to be undetectable in the new complexes is undoubtedly because of unfavorable clashes between the equatorial ligands and the bulky N(CH(2)CH(2))(2)Y ring moiety of the axial amidine ligand. The amidine formation reactions in acetonitrile (25 °C) proceeded more easily with 2 than with 1, indicating that the distortion in 6,6'-Me(2)bipy resulting from the proximity of the methyl substituents to the inner coordination sphere enhanced the reactivity of the coordinated CH(3)CN. Reaction times for 1 and 2 exhibited a similar dependence on the basicity and ring size of the heterocyclic amine reactants. Moreover, when the product of the reaction of 1 with piperidine, fac-[Re(CO)(3)(5,5'-Me(2)bipy)(HNC(CH(3))N(CH(2)CH(2))(2)CH(2))]BF(4), was challenged in acetonitrile-d(3) or CDCl(3) with a 5-fold excess of the strong 4-dimethylaminopyridine ligand, there was no evidence for replacement of the amidine ligand after two months, thus establishing that the piperidinylamidine ligand is a robust ligand. This chemistry offers promise as a suitable means for preparing isomerically pure conjugated fac-[(99m)Tc(CO)(3)L](n±) imaging agents, including conjugates with known bioactive heterocyclic amines.
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Affiliation(s)
| | - Patricia A. Marzilli
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
| | - Theshini Perera
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
| | - Frank R. Fronczek
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
| | - Luigi G. Marzilli
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
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48
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Xu J, Wang R, Li Y, Gao Z, Yao R, Wang S, Wu B. Chiral Supramolecular Frameworks Based on Chiral Metallocycles: Crystal Structures and Photophysical Properties. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200100] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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49
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Pirmettis I, Arano Y, Tsotakos T, Okada K, Yamaguchi A, Uehara T, Morais M, Correia JDG, Santos I, Martins M, Pereira S, Triantis C, Kyprianidou P, Pelecanou M, Papadopoulos M. New (99m)Tc(CO)(3) mannosylated dextran bearing S-derivatized cysteine chelator for sentinel lymph node detection. Mol Pharm 2012; 9:1681-92. [PMID: 22519912 DOI: 10.1021/mp300015s] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The aim of the present study is to synthesize new mannosylated dextran derivative that can be labeled with Tc-99m for potential use in sentinel lymph node detection (SLND). The compound was designed to have a dextran with molecular weight of 10 kDa as a backbone, mannose for binding to mannose receptors of the lymph node and S-derivatized cysteine as a suitable chelator for labeling with [(99m)Tc(H(2)O)(3)(CO)(3)](+) precursor. Reaction of allyl bromide with dextran (MW 11800) yielded the intermediate allyl-dextran (1) with about 40% coupling. Addition of cysteine to allyl-dextran resulted in the S-derivatized cysteine, compound DC15 (2). The final product DCM20 (3) was obtained in good yield after in situ hydrolysis and activation of cyanomethyl tetraacetyl-1-thio-d-mannopyranoside and coupling to DC15. All derivatives were purified by ultrafiltration and characterized by NMR. DC15 and DCM20 were quantitatively labeled with (99m)Tc (>95% radiochemical purity) using the fac-[(99m)Tc(OH(2))(3)(CO)(3)](+) precursor and ligand concentration of 1.5 × 10(-6) M at neutral pH. Both (99m)Tc-labeled compounds (99m)Tc(CO)(3)-DC15 (6) and (99m)Tc(CO)(3)-DCM20 (7) remained stable after 6 h incubation at 37 °C in the presence of excess histidine or cysteine, as well as even after 20-fold dilution and incubation for 24 h at room temperature. The characterization of the compounds 6 and 7 was performed by comparing their HPLC radiochromatograms with those of their rhenium surrogates Re(CO)(3)-DC15 (4) and Re(CO)(3)-DCM20 (5) respectively that were prepared using the precursor [NEt(4)](2)fac-[ReBr(3)(CO)(3)] and characterized by IR and NMR spectroscopy. When injected subcutaneously from the foot pad of mice, (99m)Tc-labeled mannosylated dextran (7) showed accumulation in the popliteal lymph node (SLN in this model) higher than that of non-mannosylated analogue (6) and the (99m)Tc-phytate serving as standard. Compound 7 also exhibited lower radioactivity levels at the injection site compared to (99m)Tc-phytate. The SPECT/CT studies in mice confirmed that 7 accumulated in the popliteal lymph node allowing its clear visualization. The present findings demonstrate that compound 7 ((99m)Tc(CO)(3)-DCM20) is promising and merits further evaluation as a radiopharmaceutical for sentinel lymph node detection.
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Affiliation(s)
- I Pirmettis
- Institute of Radioisotopes and Radiodiagnostic Products, NCSR Demokritos, 15310 Ag. Paraskevi, Athens, Greece.
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50
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Makris G, Karagiorgou O, Papagiannopoulou D, Panagiotopoulou A, Raptopoulou CP, Terzis A, Psycharis V, Pelecanou M, Pirmettis I, Papadopoulos MS. Rhenium(I) and Technetium(I) Tricarbonyl Complexes with [NSO]-Type Chelators: Synthesis, Structural Characterization, and Radiochemistry. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200056] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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