**2. Ferrocene derivatives**

Extensive applications of ferrocene and its derivative compounds in material science, homogeneous catalysis [15], nonlinear optics [16], and molecular sensors are observed [17]. Furthermore, an unexpected biological activity is often witnessed upon incorporating a fragment of ferrocene into a molecule of an organic compound [18]. Many ferrocene derivative compounds exhibit stimulating cytotoxic, antimalarial, antitumor, antioxidant, antifungal, and DNA-cleaving activity [19–21].

The anticancer [22] perspective of ferrocenyl derivative compounds was first premeditated around the 1970s. Brynes and collaborators explored the counter tumor action of ferrocenyl compounds containing amide or amine moieties against leukemia P-388 of the lymphocytic system [23]. They administrated these derivative compounds to mice intraperitoneally using either water or surfactant with water as Tween-80: water. The anti-tumor action of these compounds was considerable enough to show that the incorporation of the ferrocenyl moiety into an appropriate bearer could provide a drug with elevated antitumorous activity (**Figure 1**) [23].

Extensive study is carried out about ferrocene and its derivative compounds as efficient chemotherapeutic agents [24]. Stability, electroactivity, and extraordinary spectroscopic actions of ferrocene-incorporated organometallics are reasoned for being auspicious contenders for various biological applicabilities [25–27]. With reversible redox characteristics and elevated cell penetrability owing to its extensive lipophilicity, ferrocenyl moiety is responsible for pronounced characteristics of ferrocenyl derivative

**Figure 1.** *Structure of ferrocene.*

**53**

**Figure 3.**

*Some representative ferrocenyl ureas and thioureas.*

*Supramolecular Chemistry and DNA Interaction Studies of Ferrocenyl Ureas and Thioureas*

compounds [28]. For example, enhanced anticancer activity was observed when ferrocene was incorporated into tamoxifen which is a potent anticancer drug i.e. Ferrocenyl

Among the various ferrocenyl derivative compounds are i.e. amides, amines, polyacids, polymers, ureas, thioureas, and sulfonamide derivatives [30]. A lot of work is happening on the applications of ferrocenyl urea and thiourea compounds due to their pronounced interactions, supramolecular chemistry, electrochemical characteristics, and DNA interactions. Following are some examples of ferrocenyl urea and thiourea derivative compounds checked for their various activities depicted in **Figure 3** [30].

Urea (R1R2NC〓ONR3R4) is a striking building block in consequence of its widespread bioactivities and extensive bioavailability from natural products [31]. Among the urea derivative compounds, urea derivatives having aromaticity in them such as N-phenyl-N-(2-chloroethyl)urea and heterocyclic urea derivatives illustrate potential anticancer activities because of their efficient inhibitory effect against the

Urea is ascertained to be an appealing building obstruct for receptors of anion as it contributes two comparatively robust H-bonding positions [33]. The two N▬H groups in urea are able to make a bond with the only acceptor atom to form a ring structure comprising six-membered chelate or bind with two nearby oxygen atoms in an oxy-anion to give a ring structure consisting of eight-membered chelate as

derivative verified against lymphocytic leukemia P-388 (**Figure 2**) [29].

*DOI: http://dx.doi.org/10.5772/intechopen.84412*

**3. Ferrocenyl ureas and thiourea**

receptor tyrosine kinases (RTKs) [32].

**3.1 Ferrocenyl ureas**

**Figure 2.** *Ferrocenyl derivative verified against lymphocytic leukemia P-388.*

*Supramolecular Chemistry and DNA Interaction Studies of Ferrocenyl Ureas and Thioureas DOI: http://dx.doi.org/10.5772/intechopen.84412*

compounds [28]. For example, enhanced anticancer activity was observed when ferrocene was incorporated into tamoxifen which is a potent anticancer drug i.e. Ferrocenyl derivative verified against lymphocytic leukemia P-388 (**Figure 2**) [29].
