Isomer abundance of bis(beta-diketonato) complexes of titanium(IV). Crystal structures of the antitumor compound budotitane [Ti(IV)(bzac)(2)(OEt)(2)] and of its dichloro-derivative [Ti(IV)(bzac)(2)Cl(2)] (bzac=1-phenylbutane-1,3-dionate).

Abstract

The molecular tumor inhibiting titanium compound budotitane [Ti(IV)(bzac)(2)(OEt)(2)] (1) and its dichloro-derivative [Ti(IV)(bzac)(2)Cl(2)] (2) (bzac=1-phenylbutane-1,3-dionate) have been crystallized and characterized by X-ray crystallography and further physical methods. Budotitane (1) crystallizes in the tetragonal, non-centrosymmetric space group P4(1) with two molecules in the asymmetric unit. Both molecules adopt the cis-cis-trans configuration with the acetyl ends of the benzoylacetonate ligands in the trans position. The dichloro-derivative of budotitane, [Ti(IV)(bzac)(2)Cl(2)] (2) crystallizes in the monoclinic, centrosymmetric space group P2(1)/n with one molecule only in the asymmetric unit. In contrast to budotitane (1), (2) shows a cis-trans-cis arrangement with the benzoyl groups in the trans position. In both complexes there are equal numbers of Delta and Lambda enantiomers within the unit cell. The phenyl groups in (1) as well as in (2) are in approximately coplanar conjugation to the metal enolate rings. The thermal degradation of budotitane (1) was investigated in the temperature range from 25 degrees C up to 800 degrees C and reveals the formation of Ti(IV)O(bzac(2-)) as an intermediate and of the rutile phase of TiO(2) as a final product. It may be worthwhile to introduce budotitane in the form of isomerically pure crystals in the preparation of the drug used for future tests.

• Authors: Erich Dubler, Ralph Buschmann, Helmut W Schmalle
• Journal: Journal of inorganic biochemistry (J Inorg Biochem) Vol. 95 Issue 2-3 Pg. 97-104 (Jun 01 2003) ISSN: 0162-0134 [Print] United States
• PMID: 12763653 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents
• Hydrocarbons, Chlorinated
• Organometallic Compounds
• titanium dioxide
• Titanium
• diethoxy-(1-phenyl-1,3-butanedionato)titanium (IV)

Topics

• Antineoplastic Agents (chemistry)
• Crystallography, X-Ray
• Hydrocarbons, Chlorinated (chemistry)
• Isomerism
• Models, Molecular
• Organometallic Compounds (chemistry)
• Structure-Activity Relationship
• Temperature
• Thermogravimetry (methods)
• Titanium (chemistry)