Die Chemie der Cyclopentadienyltitan(IV)Verbindungen in w��rigem Medium

Döppert, Karl

doi:10.1007/bf01131789

Cited by 17 publications

(8 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Besides those resonances, the 1 H NMR spectra of titanocene derivatives 2a–2c show, during the first 24 h, metal bound Cp species (ca. 80–90% of metal bound Cp relative to 1,4-dioxane after 1 h and less than 10% after 24 h for 2b and 2c ) similar to those detected before in D 2 O solutions of [(η 5 -C 5 H 5 ) 2 TiCl 2 ] at pD = 4.1 (singlets at δ 6.60 and 6.50 [83,87], see Supplementary data). Evaluation of cytotoxic compounds (see Cytotoxicity studies, section 3.3.1) 1c·HCl , 2b or 2c in a 1:9 D 2 O:[D 8 ]THF mixture by 1 H NMR lead to similar results.…”

Section: Resultssupporting

confidence: 77%

“…Rapid hydrolysis of halide ligands occurs through a series of equilibrium reactions in which cyclopentadienyl rings (Cp) remain metal bound at pH < 3.0–3.5. At higher pH, protonolysis of Cp initiates to give cyclopentadiene as well as insoluble, uncharacterized titanium hydrolysis products [83,84,87,89]. Accordingly, resonances due to cyclopentadiene (multiplets at δ 6.61, 6.55 and 2.98, see Supplementary data) were observed in the recorded 1 H NMR spectra of more acidic 1a·HCl-1c·HCl or 2a only after 24 h, while more basic solutions of 2b and 2c exhibit, within the first min after dilution, minor multiplets assigned to free cyclopentadiene.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Novel enantiopure cyclopentadienyl Ti(IV) oximato compounds as potential anticancer agents

Cueva-Alique

Muñoz-Moreno

Benabdelouahab

et al. 2016

Journal of Inorganic Biochemistry

View full text Add to dashboard Cite

The synthesis and characterization of new enantiopure cyclopentadienyl titanium oximato compounds (S,R)-[(η5-C5H5)Ti{κ2NO,(R)NH·HCl}Cl2] (R = Ph (phenyl) 1a·HCl, Bn (benzyl) 1b·HCl, 2-pic (2-picolyl) 1c·HCl), (S,R)-[(η5-C5H5)TiCl2{κ2NO,(Ph)NH}] (1a) and (S,R)-[(η5-C5H5)2TiCl{κ2NO,(R)NH}] (R = Ph 2a, Bn 2b, 2-pic 2c), along with studies on their behaviour in D2O at different pD values are reported. The structure of previously described ammonium-oxime (2S,5R)-{NOH,(Bn)NH·HCl} (b·HCl) and novel titanium derivative 1a have been determined by single crystal X-ray crystallography. The effect of the compounds on cytotoxicity, cell adhesion and migration of the androgen-independent prostate cancer PC-3 cells has been assessed. Compounds 2b and 2c are more cytotoxic than additive doses of titanocene dichloride and free oxime proligand, probing the synergistic effect of these novel compounds. The cytotoxicity of 2b and 2c has been further evaluated against human renal Caki-1, colon DLD-1 and triple negative breast MDA-MB-231 cancer cell lines. The activity found for 2c on PC-3 and Caki-1 is higher than that of highly active Titanocene Y (bis-[(p-methoxybenzyl)cyclopentadienyl]titanium(IV) dichloride), while showing selectivity against renal cancer when compared to a non-tumorigenic human renal (HEK-293T) cell line. Compounds 2b and especially 2c are apoptotic in Caki-1 cancer cell lines. Cell adhesion and wound-healing assays confirmed that derivatives 1c·HCl, 2b and 2c affect the adhesion and migration patterns of the PC-3 cell line. Interactions of the novel compounds with plasmid (pBR322) DNA have also been studied, showing that the oximato Ti(IV) derivatives have a weak or no interaction with DNA at physiological pH.

show abstract

Section: Resultssupporting

confidence: 77%

Section: Resultsmentioning

confidence: 99%

Novel enantiopure cyclopentadienyl Ti(IV) oximato compounds as potential anticancer agents

Cueva-Alique

Muñoz-Moreno

Benabdelouahab

et al. 2016

Journal of Inorganic Biochemistry

View full text Add to dashboard Cite

show abstract

“…68 The aqueous chemistry of the related CpTiCl 3 has been the subject of a recent review article. 89 Interestingly, aerial oxidation of a dark-green toluene solution of Cp* 2 TiF (69) affords 50 in good yield. 68 Reaction of 50 with trimethylaluminum provides intriguing insight into the interactions of group 4 and 13 compounds (eq 22).…”

Section: Titanium(iv) Monocyclopentadienylmentioning

confidence: 99%

“…In the analogous hafnium reaction Cp* 2 HfMe 2 is isolated in only 50% yield. 133 (89) among other products. 120 Dienone-mediated oxidation chemistry observed for titanocene compounds (eq 15) has proven to be general for group 4 metals.…”

Section: Zirconocene and Hafnocene Metallocenesmentioning

confidence: 99%

See 1 more Smart Citation

Organometallic Fluorides: Compounds Containing Carbon−Metal−Fluorine Fragments of d-Block Metals

1997

View full text Add to dashboard Cite

Determination of titanocene, a new drug with anticancer potential, and its metabolism in solution by capillary electrophoresis

et al. 1998

View full text Add to dashboard Cite

Titanocene dichloride is one of the most promising cancerostatica of the future: nevertheless, its high activity against several tumor cells was discovered 20 years ago. Detailed knowledge of the mechanism of hydrolysis of titanocene dichloride and its stability in the infusion liquid is a prerequisite for clinical tests and for a successful application for permission as medication. Capillary electrophoresis (CE) was used to observe the hydrolysis behavior of titanocene dichloride in aqueous solutions. The hydrolysis products were separated in a 20 mM phosphate buffer, pH 6, and in a 20 mM malic acid buffer, pH 3. Up to five hydrolysis products were obtained. A significant influence of the sample preparation (pH, isoionic additives) on the hydrolysis rate was observed. The hydrolysis products were characterized by the UV scan and the element-selective particle-induced X-ray emission (PIXE) detection technique. The results obtained correspond with the hydrolysis mechanism described in the literature. The determination of free titanocene dichloride in human plasma failed due to the high affinity of the plasma proteins for this compound.

show abstract

Die Chemie der Cyclopentadienyltitan(IV)Verbindungen in w��rigem Medium

Cited by 17 publications

References 35 publications

Novel enantiopure cyclopentadienyl Ti(IV) oximato compounds as potential anticancer agents

Novel enantiopure cyclopentadienyl Ti(IV) oximato compounds as potential anticancer agents

Organometallic Fluorides: Compounds Containing Carbon−Metal−Fluorine Fragments of d-Block Metals

Determination of titanocene, a new drug with anticancer potential, and its metabolism in solution by capillary electrophoresis

Contact Info

Product

Resources

About