BIOMAT Database Logo BIOMAT Database Logo

Modulation of water exchange in europium(III) DOTA-tetraamide complexes via electronic substituent effects. 2008

S James Ratnakar, and Mark Woods, and Angelo J M Lubag, and Zoltan Kovacs, and A Dean Sherry
Advanced Imaging Research Center, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.

The chemical exchange saturation transfer (CEST) efficiency for a series Eu3+-based tetraamide complexes bearing p-substituents on a single coordinating pendant arm is highly sensitive to water exchange rates. The CEST effect increases in the order Me < MeO < F approximately CO2tBu < CN < H. These results show that CEST contrast can be modulated by changes in electron density at a single ligating atom, and this forms the basis of creating imaging agents that respond to chemical oxidation and reduction.

UI MeSH Term Description Entries
D008024 Ligands A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed) Ligand
D009942 Organometallic Compounds A class of compounds of the type R-M, where a C atom is joined directly to any other element except H, C, N, O, F, Cl, Br, I, or At. (Grant & Hackh's Chemical Dictionary, 5th ed) Metallo-Organic Compound,Metallo-Organic Compounds,Metalloorganic Compound,Organometallic Compound,Metalloorganic Compounds,Compound, Metallo-Organic,Compound, Metalloorganic,Compound, Organometallic,Compounds, Metallo-Organic,Compounds, Metalloorganic,Compounds, Organometallic,Metallo Organic Compound,Metallo Organic Compounds
D010084 Oxidation-Reduction A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471). Redox,Oxidation Reduction
D003287 Contrast Media Substances used to allow enhanced visualization of tissues. Radiopaque Media,Contrast Agent,Contrast Agents,Contrast Material,Contrast Materials,Radiocontrast Agent,Radiocontrast Agents,Radiocontrast Media,Agent, Contrast,Agent, Radiocontrast,Agents, Contrast,Agents, Radiocontrast,Material, Contrast,Materials, Contrast,Media, Contrast,Media, Radiocontrast,Media, Radiopaque
D004583 Electrons Stable elementary particles having the smallest known negative charge, present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers, energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS. Fast Electrons,Negatrons,Positrons,Electron,Electron, Fast,Electrons, Fast,Fast Electron,Negatron,Positron
D005063 Europium An element of the rare earth family of metals. It has the atomic symbol Eu, atomic number 63, and atomic weight 152. Europium is used in the form of its salts as coatings for cathode ray tubes and in the form of its organic derivatives as shift reagents in NMR spectroscopy.
D000577 Amides Organic compounds containing the -CO-NH2 radical. Amides are derived from acids by replacement of -OH by -NH2 or from ammonia by the replacement of H by an acyl group. (From Grant & Hackh's Chemical Dictionary, 5th ed) Amide
D013329 Structure-Activity Relationship The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups. Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships
D014867 Water A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed) Hydrogen Oxide

Related Publications

S James Ratnakar, and Mark Woods, and Angelo J M Lubag, and Zoltan Kovacs, and A Dean Sherry
Europium(III) DOTA-tetraamide complexes as redox-active MRI sensors.
April 2012, Journal of the American Chemical Society,
S James Ratnakar, and Mark Woods, and Angelo J M Lubag, and Zoltan Kovacs, and A Dean Sherry
Modulation of water exchange in Eu(III) DOTA-tetraamide complexes: considerations for in vivo imaging of PARACEST agents.
January 2009, Contrast media & molecular imaging,
S James Ratnakar, and Mark Woods, and Angelo J M Lubag, and Zoltan Kovacs, and A Dean Sherry
Multi-frequency PARACEST agents based on europium(III)-DOTA-tetraamide ligands.
January 2009, Angewandte Chemie (International ed. in English),
S James Ratnakar, and Mark Woods, and Angelo J M Lubag, and Zoltan Kovacs, and A Dean Sherry
Investigations into whole water, prototropic and amide proton exchange in lanthanide(III) DOTA-tetraamide chelates.
July 2011, Dalton transactions (Cambridge, England : 2003),
S James Ratnakar, and Mark Woods, and Angelo J M Lubag, and Zoltan Kovacs, and A Dean Sherry
A bridge to coordination isomer selection in lanthanide(III) DOTA-tetraamide complexes.
April 2007, Inorganic chemistry,
S James Ratnakar, and Mark Woods, and Angelo J M Lubag, and Zoltan Kovacs, and A Dean Sherry
Europium(III) DOTA-derivatives having ketone donor pendant arms display dramatically slower water exchange.
March 2011, Inorganic chemistry,
S James Ratnakar, and Mark Woods, and Angelo J M Lubag, and Zoltan Kovacs, and A Dean Sherry
The pH sensitivity of -NH exchange in LnDOTA-tetraamide complexes varies with amide substituent.
January 2011, Contrast media & molecular imaging,
S James Ratnakar, and Mark Woods, and Angelo J M Lubag, and Zoltan Kovacs, and A Dean Sherry
The effect of the amide substituent on the biodistribution and tolerance of lanthanide(III) DOTA-tetraamide derivatives.
December 2008, Investigative radiology,
S James Ratnakar, and Mark Woods, and Angelo J M Lubag, and Zoltan Kovacs, and A Dean Sherry
pH-sensitive modulation of the second hydration sphere in lanthanide(III) tetraamide-DOTA complexes: a novel approach to smart MR contrast media.
October 2003, Chemistry (Weinheim an der Bergstrasse, Germany),
S James Ratnakar, and Mark Woods, and Angelo J M Lubag, and Zoltan Kovacs, and A Dean Sherry
Synthesis and luminescence studies of aryl substituted tetraamide complexes of europium(III): a new approach to pH responsive luminescent europium probes.
July 2003, Inorganic chemistry,
Copied contents to your clipboard!