Misplaced Pages

DOTA (chelator)

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.

This is an old revision of this page, as edited by Beetstra (talk | contribs) at 10:52, 31 October 2011 (Script assisted update of identifiers for the Chem/Drugbox validation project (updated: 'CASNo').). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Revision as of 10:52, 31 October 2011 by Beetstra (talk | contribs) (Script assisted update of identifiers for the Chem/Drugbox validation project (updated: 'CASNo').)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)
DOTA
DOTA
DOTA
Names
IUPAC name 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid
Other names DOTA, DotA, tetraxetan
Identifiers
3D model (JSmol)
ECHA InfoCard 100.113.833 Edit this at Wikidata
PubChem CID
CompTox Dashboard (EPA)
InChI
  • InChI=1S/C16H28N4O8/c21-13(22)9-17-1-2-18(10-14(23)24)5-6-20(12-16(27)28)8-7-19(4-3-17)11-15(25)26/h1-12H2,(H,21,22)(H,23,24)(H,25,26)(H,27,28)Key: WDLRUFUQRNWCPK-UHFFFAOYSA-N
SMILES
  • O=C(O)CN(CC1)CCN(CC(=O)O)CCN(CC(=O)O)CCN1CC(=O)O
Properties
Chemical formula C16H28N4O8
Molar mass 404.420 g·mol
Appearance White crystalline solid
Hazards
GHS labelling:
Pictograms GHS07: Exclamation mark
Signal word Warning
Hazard statements H315, H319, H335
Precautionary statements P261, P305+P351+P338
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). checkY verify (what is  ?) Infobox references
Chemical compound For other uses, see DOTA (disambiguation).

1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (also known as DOTA) is an organic compound with the formula (CH2CH2NCH2CO2H)4. The molecule consists of a central 12-membered tetraaza (i.e., containing four nitrogen centers) ring. DOTA is used as a complexing agent, especially for lanthanide ions. Its complexes have medical applications as contrast agents and cancer treatments.

Terminology

The acronym DOTA is jargon for both the tetracarboxylic acid and its various conjugate bases. In the area of coordination chemistry, the tetraacid is called H4DOTA and its fully deprotonated derivative is DOTA. Many related ligands are referred to using the DOTA acronym, although these derivatives are generally not tetracarboxylic acids or the conjugate bases.

Structure

DOTA is derived from the macrocycle known as cyclen. The four secondary amine groups are modified by replacement of the N-H centers with N-CH2CO2H groups. The resulting polyamino carboxylic acid, upon ionization of the carboxylic acid groups, is a high affinity chelating agent for di- and trivalent cations. The tetracarboxylic acid was first reported in 1976. At the time of its discovery DOTA exhibited the largest known formation constant for the complexation (chelating) of Ca and Gd ions. Modified versions of DOTA were first reported in 1988 and this area has proliferated since.

As a polydentate ligand, DOTA envelops metal cations, but the denticity of the ligand depends on the geometric tendencies of the metal cation. The main applications involve the lanthanides and in such complexes DOTA functions as an octadentate ligand, binding the metal through four amine and four carboxylate groups. Most such complexes feature an additional water ligand, giving an overall coordination number of nine.

For most transition metals, DOTA functions as a hexadentate ligand, binding through the four nitrogen and two carboxylate centres. The complexes have octahedral coordination geometry, with two pendent carboxylate groups. In the case of , the ligand is heptadentate.

Uses

Cancer treatment and diagnosis

DOTA is used as part of some cancer therapies, where it functions as a chelating agent for the radioisotope Y. DOTA can be conjugated to monoclonal antibodies by attachment of one of the four carboxyl groups as an amide. The remaining three carboxylate anions are available for binding to the yttrium ion. The modified anitibody accumulates in the tumour cells, concentrating the effects of the radioactivity of Y. Drugs containing this module receive an International Nonproprietary Name ending in tetraxetan:

DOTA can also be linked to molecules that have affinity for various structures. The resulting compounds are used with a number of radioisotopes in cancer therapy and diagnosis (for example in positron emission tomography).

Contrast agent

The complex of Gd and DOTA is used as a gadolinium-based MRI contrast agent under the name gadoteric acid.

Synthesis

DOTA was first synthesized in 1976 from cyclen and bromoacetic acid. This method is simple and still in use.

References

  1. ^ Nerissa Viola-Villegas, Robert P. Doyle "The coordination chemistry of 1,4,7,10-tetraazacyclododecane-N,N′,N″,N′″-tetraacetic acid (H4DOTA): Structural overview and analyses on structure–stability relationships" Coordination Chemistry Reviews Volume 253, 2009, pp1906-1925. doi:10.1016/j.ccr.2009.03.013
  2. ^ Stetter, Hermann (1976). "Complex Formation with Tetraazacycloalkane-N,N',N'',N''';-tetraacetic Acids as a Function of Ring Size". Angewandte Chemie International Edition in English. 15 (11): 686. doi:10.1002/anie.197606861. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  3. Moi, Min K. (1988). "The peptide way to macrocyclic bifunctional chelating agents: synthesis of 2-(p-nitrobenzyl)-1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid and study of its yttrium(III) complex". Journal of the American Chemical Society. 110 (18): 6266–6267. doi:10.1021/ja00226a063. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  4. Volkert, Wynn A. (1999). "Therapeutic Radiopharmaceuticals". Chemical Reviews. 99 (9): 2269–2292. doi:10.1021/cr9804386. PMID 11749482. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  5. "Statement On A Nonproprietary Name Adopted By The USAN Council: Yttrium Y90 clivatuzumab tetraxetan" (PDF). American Medical Association.
  6. PMID 21624565
  7. PMID 10717908
  8. A Clinical Study of Gadoteric Acid in Non-Coronary Magnetic Resonance (MR) Angiography
  9. Knör, S; Modlinger, A; Poethko, T; Schottelius, M; Wester, HJ; Kessler, H (2007). "Synthesis of novel 1,4,7,10-tetraazacyclodecane-1,4,7,10-tetraacetic acid (DOTA) derivatives for chemoselective attachment to unprotected polyfunctionalized compounds". Chemistry (Weinheim an der Bergstrasse, Germany). 13 (21): 6082–90. doi:10.1002/chem.200700231. PMID 17503419.
Categories: