Fluorinated Derivatives of Titanocene Y: Synthesis and Cytotoxicity Studies

Gold Derivatives Development as Prospective Anticancer Drugs for Breast Cancer Treatment

Commonly used anticancer drugs are cisplatin and other platinum-based drugs. However, the use of these drugs in chemotherapy causes numerous side effects and the onset of frequent drug resistance phenomena. This review summarizes the most recent results on the gold derivatives used for their significant inhibitory effects on the in vitro proliferation of breast cancer cell models and for the consequences deriving from morphological changes in the same cells. In particular, the study discusses the antitumor activity of gold nanoparticles, gold (I) and (III) compounds, gold complexes and carbene-based gold complexes, compared with cisplatin. The results of screening studies of cytotoxicity and antitumor activity for the gold derivatives show that the death of cancer cells can occur intrinsically by apoptosis. Recent research has shown that gold (III) compounds with square planar geometries, such as that of cisplatin, can intercalate the DNA and provide novel anticancer agents. The gold derivatives described can make an important contribution to expanding the knowledge of medicinal bioorganometallic chemistry and broadening the range of anticancer agents available, offering improved characteristics, such as increased activity and/or selectivity, and paving the way for further discoveries and applications.

Novel Gold and Silver Carbene Complexes Exert Antitumor Effects Triggering the Reactive Oxygen Species Dependent Intrinsic Apoptotic Pathway

Cisplatin and other platinum-based drugs are well-known valid anticancer drugs. However, during chemotherapy, the presence of numerous side effects and the onset of frequent phenomena of resistance has pushed many research groups to devise new metal-based compounds holding improved anticancer properties and fewer undesired effects. Amongst the variety of synthesized compounds, significant antiproliferative effects have been obtained by employing organometallic compounds, particularly those based on silver and gold. With this in mind, we synthesized four compounds, two silver complexes and two gold complexes, with good inhibitory effects on the in vitro proliferation of breast and ovarian cancer-cell models. The antitumor activity of the most active compound, that is, AuL4, was found to be ninefold higher than that of cisplatin, and this compound induced dramatic morphological changes in HeLa cells. AuL4 induced PARP-1 cleavage, caspases 3/7 and 9 activation, mitochondria disruption, cytochrome c release in cancer-cell cytoplasm, and the intracellular production of reactive oxygen species. Thus, AuL4 treatment caused cancer-cell death by the intrinsic apoptotic pathway, whereas no cytotoxic effects were recorded upon treating non-tumor cell lines. The reported outcomes may be an important contribution to the expanding knowledge of medicinal bio-organometallic chemistry and enlarge the available anticancer toolbox, offering improved features, such as higher activity and/or selectivity, and opening the way to new discoveries and applications.

Synthesis and Antitumor Activity of New Group 3 Metallocene Complexes

The quest for alternative drugs with respect to the well-known cis-platin and its derivatives, which are still used in more than 50% of the treatment regimens for patients suffering from cancer, is highly needed. In this context, organometallic compounds, which are defined as metal complexes containing at least one direct covalent metal-carbon bond, have recently been found to be promising anticancer drug candidates. A series of new metallocene complexes with scandium, yttrium, and neodymium have been prepared and characterized. Some of these compounds show a very interesting anti-proliferative activity in triple negative breast cancer cell line (MDA.MB231) and the non-hormone sensitive prostate cancer cell line (DU145). Moreover, the interaction of some of them with biological membranes, evaluated using liposomes as bio-membrane mimetic model systems, seems to be relevant. The biological activity of these compounds, particularly those based on yttrium, already effective at low concentrations on both cancer cell lines, should be taken into account with regard to new therapeutic approaches in anticancer therapy.

Regio- and diastereoselective synthesis of (E)-3-(2-aminochromen-4-yl)-6-aryl-substituted fulvenes

A practical base-catalyzed route was developed for the regio- and diastereoselective synthesis of (E)-3-aminochromene-6-aryl-disubstituted fulvenes in high yields up to 94% starting with the Michael addition of cyclopentadiene to 2-iminochromenes in the key step.

Heteroleptic titanium(IV) catecholato/piperazine systems and their anti-cancer properties

In this paper we report the synthesis and full characterisation of a range of Ti(IV)-catecholato systems complexed to piperazine or homopiperazine salan ligands. The steric/electronic environment of the catecholate moiety has been varied and the effect this has on cytotoxicity discussed. It was observed that the 7-membered homopiperazine complexes are more stable to hydrolysis than their piperazine cousins in biological media. In general the homopiperazine complexes show higher cytotoxicity than the piperazine complexes, with the most cytotoxic complex exhibiting IC50 (μM) values of 3 ± 0.5 μM (HT-29) and 4 ± 1 μM (OVCAR).

Synthesis, characterization and cytotoxic activity on breast cancer cells of new half-titanocene derivatives

A series of novel titanocene-complexes has been prepared and evaluated for their growth regulatory effects in MCF7 and SkBr3 breast cancer cells. The capability of some of these compound to elicit relevant repressive effects on cancer cell growth could be taken into account towards novel pharmacological approaches in cancer therapy.

Cytotoxic properties of titanocenyl amides on breast cancer cell line mcf-7

A new titanocenyl amide containing flavone as pendant group has been synthesized by reaction of titanocenyl carboxylic acid chloride and 7-Aminoflavone and structurally characterized by spectroscopic methods. This species and eight previously synthesized titanocenyl amide complexes have been tested in breast adenocarcinoma cancer cell line, MCF-7. The functionalization of titanocene dichloride with amides enhances the cytotoxic activity in MCF-7. Two sets of titanocenyl amides can be identified, with IC(50) <100 muM and IC(50)>100 muM. The most cytotoxic species is Cp(CpCO-NH-C(6)H(4)-(CH(2))(2)CH(3))TiCl(2) with an IC(50) of 24(2) muM, followed by Cp(CpCO-NH-C(6)H(4)-Br)TiCl(2), IC(50) of 46(4) muM and Cp(CpCO-NH-C(6)H(4)-OCF(3))TiCl(2), IC(50) of 49(6) muM. There is no correlation between the nature of the para substituent on the phenyl ring and the cytotoxic properties on MCF-7 cell line.

Synthesis, Structure and Biological Activity of Amide-Functionalized Titanocenyls: Improving their Cytotoxic Properties

Nine amide-functionalized titanocenyls have been synthesized and characterized by spectroscopic and analytical methods and the solid state structure of Cp(CpCO-NH-C(6)H(4)-OCF(3))TiCl(2) was determined by single crystal X-ray diffraction. X-ray analysis of Cp(CpCO-NH-C(6)H(4)-OCF(3))TiCl(2) showed that titanium is in a pseudo tetrahedral geometry and contains a Ti-O(amide) coordination. In principle, Ti-O coordination should provide more hydrolytic stability to the corresponding titanocenyls than titanocene dichloride. The cytotoxic activities of these amide-functionalized titanocenyls on HT-29 colon cancer cell line were determined by MTT assay to elucidate structure-activity relationship. All complexes were more cytotoxic than titanocene dichloride and there is no correlation between the para substituents on the phenyl ring and their cytotoxicities.