Tc‐99m und deuterium markierte gehirn‐affine radiodiagnostika ‐ vergleich von HMPAO mit cytectren‐derivaten cyclischer amine

Wenzel, Martin; Klinge, Carolyn M.; Saidi, Mouldi

doi:10.1002/jlcr.2580331107

Cited by 5 publications

(3 citation statements)

References 6 publications

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“…The rarely exploited oxidation state +1 came into the limelight by the discovery of myocardium affine hexakis isonitriles of technetium(I) and the successful clinical application of 99m Tc methoxy-isobutyl isonitrile (). Despite this progress, the oxidation state +1 has been addressed only in a minor way ( − ) before a new most promising approach to low valent, inert technetium compounds on basis of Tc(I) carbonyl complexes has been elaborated ( − ). Intensive investigations in the Tc carbonyl chemistry made available an organometallic Tc(I) aqua ion, [Tc(H 2 O) 3 (CO) 3 ] + , from TcO 4 - under normal pressure, the prerequisite to exploit the small [Tc(CO) 3 ] + moiety for the labeling of biomolecules is given ( , ).…”

Section: Introductionmentioning

confidence: 99%

Chemical and Biological Characterization of Technetium(I) and Rhenium(I) Tricarbonyl Complexes with Dithioether Ligands Serving as Linkers for Coupling the Tc(CO)₃ and Re(CO)₃ Moieties to Biologically Active Molecules

Pietzsch¹,

Gupta²,

Reisgys³

et al. 2000

Bioconjugate Chem.

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The organometallic precursor (NEt(4))(2)[ReBr(3)(CO)(3)] was reacted with bidendate dithioethers (L) of the general formula H(3)C-S-CH(2)CH(2)-S-R (R = -CH(2)CH(2)COOH, CH(2)-C&tbd1;CH) and R'-S-CH(2)CH(2)-S-R' (R' = CH(3)CH(2)-, CH(3)CH(2)-OH, and CH(2)COOH) in methanol to form stable rhenium(I) tricarbonyl complexes of the general composition [ReBr(CO)(3)L]. Under these conditions, the functional groups do not participate in the coordination. As a prototypic representative of this type of Re compounds, the propargylic group bearing complex [ReBr(CO(3))(H(3)C-S-CH(2)CH(2)-S-CH(2)C&tbd1;CH)] Re2 was studied by X-ray diffraction analysis. Its molecular structure exhibits a slightly distorted octahedron with facial coordination of the carbonyl ligands. The potentially tetradentate ligand HO-CH(2)CH(2)-S-CH(2)CH(2)-S-CH(2)CH(2)-OH was reacted with the trinitrato precursor [Re(NO(3))(3)(CO)(3)](2-) to yield a cationic complex [Re(CO)(3)(HO-CH(2)CH(2)-S-CH(2)CH(2)-S-CH(2)CH(2)-OH)]NO(3) Re8 which shows the coordination of one hydroxy group. Re8 has been characterized by correct elemental analysis, infrared spectroscopy, capillary electrophoresis, and X-ray diffraction analysis. Ligand exchange reaction of the carboxylic group bearing ligands H(3)C-S-CH(2)CH(2)-S-CH(2)CH(2)-COOH and HOOC-CH(2)-S-CH(2)CH(2)-S-CH(2)-COOH with (NEt(4))(2)[ReBr(3)(CO)(3)] in water and with equimolar amounts of NaOH led to complexes in which the bromide is replaced by the carboxylic group. The X-ray structure analysis of the complex [Re(CO)(3)(OOC-CH(2)-S-CH(2)CH(2)-S-CH(2)-COOH)] Re6 shows the second carboxylic group noncoordinated offering an ideal site for functionalization or coupling a biomolecule. The no-carrier-added preparation of the analogous (99m)Tc(I) carbonyl thioether complexes could be performed using the precursor fac-[(99m)Tc(H(2)O)(3)(CO)(3)](+), with yields up to 90%. The behavior of the chlorine containing (99m)Tc complex [(99m)TcCl(CO)(3)(CH(3)CH(2)-S-CH(2)CH(2)-S-CH(2)CH(3))] Tc1 in aqueous solution at physiological pH value was investigated. In saline, the chromatographically separated compound was stable for at least 120 min. However, in chloride-free aqueous solution, a water-coordinated cationic species Tc1a of the proposed composition [(99m)Tc(H(2)O)(CO)(3)(CH(3)CH(2)-S-CH(2)CH(2)-S-CH(2)CH(3))](+) occurred. The cationic charge of the conversion product was confirmed by capillary electrophoresis. By the introduction of a carboxylic group into the thioether ligand as a third donor group, the conversion could be suppressed and thus the neutrality of the complex preserved. Biodistribution studies in the rat demonstrated for the neutral complexes [(99m)TcCl(CO)(3)(CH(3)CH(2)-S-CH(2)CH(2)-S-CH(2)CH(3))] Tc1 and [(99m)TcCl(CO)(3)(CH(2)-S-CH(2)CH(2)-S-CH(2)-C&tbd1;CH)] Tc2 a significant initial brain uptake (1.03 +/- 0.25% and 0.78 +/- 0.08% ID/organ at 5 min. p.i.). Challenge experiments with glutathione clearly indicated that no transchelation reaction occurs in vivo.

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Section: Introductionmentioning

confidence: 99%

Chemical and Biological Characterization of Technetium(I) and Rhenium(I) Tricarbonyl Complexes with Dithioether Ligands Serving as Linkers for Coupling the Tc(CO)₃ and Re(CO)₃ Moieties to Biologically Active Molecules

Pietzsch¹,

Gupta²,

Reisgys³

et al. 2000

Bioconjugate Chem.

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“…The first method reported by Wenzel et al for the synthesis of cytectrene-based piano-stool complexes with 99m Tc was the double ligand transfer (DLT) reaction, starting from the corresponding ferrocene (Fc) precursor. 8,9,14 later improved by Spradau et al 15 and extensively applied for the synthesis of various targeting molecules. 16 A further method allowed the direct coordination of [ 99m Tc(H 2 O) 3 (CO) 3 ] + to α-carbonyl Cps.…”

Section: ■ Introductionmentioning

confidence: 99%

“…Therefore, they are a class of compounds attractive for the development of biologically compatible imaging agents. Since the early 1990s, [Cp-R 99m Tc(CO) 3 ]-type complexes have been employed in the development of radiotracers for SPECT imaging. , Cytectrene complexes were employed to image various targets such as the central nervous system, the myocardium, cancer, and infection sites . The Re homologues were developed for therapeutic applications, thereby rendering the employed ligand systems and their complexes theranostic (applicable for both therapy and diagnostics).…”

Section: Introductionmentioning

confidence: 99%

Expanding the Cyclopentadienyl Framework: ^99mTc/Re Complexes with Orthogonal Functions for Bioconjugation

et al. 2020

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A series of bifunctional cyclopentadienes of the type 1,3-EtOCO-HCp-linker-NH2 were synthesized. In this series, the linker length (distance between the amine functionalities and the cyclopentadiene) has been systematically varied (CH2) n (n = 1–3). The corresponding Re complexes [(η5-C5H3RR′)Re(CO)3] (R = −COOEt, R′ = −linker–NH2) were synthesized and structurally characterized. They exhibit extraordinary stability toward water and air. All bifunctional cyclopentadienes have been labeled with the [99mTc(CO)3]+ moiety. Whereas the reactions with ethylene and propylene linked cyclopentadiene under mild reaction conditions led to the products in high radiochemical purity (>96%) without applying further purification protocols, harsher reaction conditions were required for the synthesis of the methylene-linked cyclopentadiene compound. Masking the amine in the methylene-linked cyclopentadiene by an amide bond bypasses this problem. The very hydrophilic characters of these complexes were assessed by K OW analysis. The reported cyclopentadienes and their complexes offer a robust and versatile platform for (radio)metal incorporation into biologically active lead structures.

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Tc‐99m markierte Östradiol‐derivate synthese, organverteilung und tumor‐affinität

Wenzel

Klinge

1994

Labelled Comp Radiopharmac

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-99m labelled estradiol-derivatives -Synthesis, organdistribution and tumor affinity summarv:As starting material for the Tc-99m labelling 17-(Ferrocenyl-ethinyl)-estradiol and 16-(Ferroceny1iden)-estron were synthesized.These ferrocene derivatives were heated w i t h Mn-Br(C0)g and Tc-99m-pertechentate to yield the labelled corresponding cytectrene steroid compounds. In organ distribution studies with infantile female rats a binding of the Tc-99m labelled steroids to the estradiol receptor in the rat uterus was demonstrated. The binding to MXT-mamma tumors in mice yielded a Tc-99m concentration ratio tumor/muscle of 3 : 1. Kev words; Tc-99m, estradiol, cytectrene, mammatumor, ferrocene Einleitung Ein zentrales Ziel der Radiophmazie ist die Madierung niedermolekularer Rezeptor-Liganden mit y-Strahlern. In der Nuclearmedizin wird zur Markierung meist Tc-99m verwendet, in der Regel in

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Tc‐99m und deuterium markierte gehirn‐affine radiodiagnostika ‐ vergleich von HMPAO mit cytectren‐derivaten cyclischer amine

Abstract: The deuterated compounds showed a lower Tc-99m concentration in blood, but no higher uptake in brain. Kev words; Tc-99m, deuterium, cytectren, HMPAO, brain uptake Einleitung

Cited by 5 publications

References 6 publications

Chemical and Biological Characterization of Technetium(I) and Rhenium(I) Tricarbonyl Complexes with Dithioether Ligands Serving as Linkers for Coupling the Tc(CO)₃ and Re(CO)₃ Moieties to Biologically Active Molecules

Chemical and Biological Characterization of Technetium(I) and Rhenium(I) Tricarbonyl Complexes with Dithioether Ligands Serving as Linkers for Coupling the Tc(CO)₃ and Re(CO)₃ Moieties to Biologically Active Molecules

Expanding the Cyclopentadienyl Framework: ^99mTc/Re Complexes with Orthogonal Functions for Bioconjugation

Tc‐99m markierte Östradiol‐derivate synthese, organverteilung und tumor‐affinität

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Tc‐99m und deuterium markierte gehirn‐affine radiodiagnostika ‐ vergleich von HMPAO mit cytectren‐derivaten cyclischer amine

Abstract: The deuterated compounds showed a lower Tc-99m concentration in blood, but no higher uptake in brain. Kev words; Tc-99m, deuterium, cytectren, HMPAO, brain uptake Einleitung

Cited by 5 publications

References 6 publications

Chemical and Biological Characterization of Technetium(I) and Rhenium(I) Tricarbonyl Complexes with Dithioether Ligands Serving as Linkers for Coupling the Tc(CO)3 and Re(CO)3 Moieties to Biologically Active Molecules

Chemical and Biological Characterization of Technetium(I) and Rhenium(I) Tricarbonyl Complexes with Dithioether Ligands Serving as Linkers for Coupling the Tc(CO)3 and Re(CO)3 Moieties to Biologically Active Molecules

Expanding the Cyclopentadienyl Framework: 99mTc/Re Complexes with Orthogonal Functions for Bioconjugation

Tc‐99m markierte Östradiol‐derivate synthese, organverteilung und tumor‐affinität

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Chemical and Biological Characterization of Technetium(I) and Rhenium(I) Tricarbonyl Complexes with Dithioether Ligands Serving as Linkers for Coupling the Tc(CO)₃ and Re(CO)₃ Moieties to Biologically Active Molecules

Chemical and Biological Characterization of Technetium(I) and Rhenium(I) Tricarbonyl Complexes with Dithioether Ligands Serving as Linkers for Coupling the Tc(CO)₃ and Re(CO)₃ Moieties to Biologically Active Molecules

Expanding the Cyclopentadienyl Framework: ^99mTc/Re Complexes with Orthogonal Functions for Bioconjugation