Titanocene Y

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Structure of Titanocene Y Titanocene Y.png
Structure of Titanocene Y

Titanocene Y also known as bis[(p-methoxybenzyl)cyclopentadienyl]titanium(IV) dichloride or dichloridobis(η5-(p-methoxybenzyl)cyclopentadienyl)titanium is an organotitanium compound that has been investigated for use as an anticancer drug. [1]



Titanocene dichloride is known to be a potential anticancer drug [2] since the late 1970s. After initial clinical trials against breast and renal-cell cancer were performed with this compound, [3] [4] the search for improved derivatives started. [5] Particularly, lipophilic titanocene dichloride derivatives derived from fulvenes [6] were synthesised in structural diversity and this led to the development of bis[(p-methoxybenzyl)cyclopentadienyl]titanium(IV) dichloride, [1] which became better known in the literature under its trivial name of Titanocene Y.

Mechanism of action

Titanocene Y is a cytotoxic apoptosis-inducing [7] and anti-angiogenic [8] drug candidate targeting renal-cell cancer and other solid tumors. [9] [10] The compound is transported via serum albumin selectively into cancer cells [11] [12] and targets their DNA by coordinating strongly to phosphate groups. [13] [14] Additionally, Titanocene Y is able to induce apoptosis via the FAS receptor pathway. [15] Very encouraging is the fact that Titanocene Y is breaking platinum-resistance in human colon and human lung cancer cells, [16] which might make it attractive as a cytotoxic component of future 2nd or 3rd line cancer treatments.

Animal testing

Titanocene Y was tested extensively in vivo; it showed promising results against xenografted human epidermoid carcinoma [17] and prostate cancer, [18] while best results are reached against breast [19] and renal-cell cancer. [20] Titanocene Y can be given in the mouse in high dosages and it shows generally mild toxicity in the form of diarrhea. Titanocene Y is not patent protected and would therefore benefit from non-commercial sponsoring to develop it into a cytotoxic drug candidate for the treatment of advanced renal-cell cancer – an area in need of better therapies.

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<span class="mw-page-title-main">Titanocene dichloride</span> Chemical compound

Titanocene dichloride is the organotitanium compound with the formula (η5-C5H5)2TiCl2, commonly abbreviated as Cp2TiCl2. This metallocene is a common reagent in organometallic and organic synthesis. It exists as a bright red solid that slowly hydrolyzes in air. It shows antitumour activity and was the first non-platinum complex to undergo clinical trials as a chemotherapy drug.

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<span class="mw-page-title-main">Titanocene pentasulfide</span> Chemical compound

Titanocene pentasulfide is the organotitanium compound with the formula (C5H5)2TiS5, commonly abbreviated as Cp2TiS5. This metallocene exists as a bright red solid that is soluble in organic solvents. It is of academic interest as a precursor to unusual allotropes of elemental sulfur as well as some related inorganic rings.

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<span class="mw-page-title-main">(Cyclopentadienyl)titanium trichloride</span> Chemical compound

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