Question

The complex used as an anticancer agent is:
A.\[trans - [Co{(N{H_3})_3}C{I_3}]\]
B.\[cis - [PtC{l_2}{(N{H_3})_2}]\]
C.\[cis - {K_2}[PtB{r_2}C{l_2}]\]
D.$N{a_2}C{O_3}$

Answer 1

Hint: To answer this question, recall the concept of the therapeutic use of transition metals. It is a fact that transition metals are necessary in several biological processes, from electron transfer to enzyme cofactors. The drug used for anti-cancer treatment is also known as cisplatin.

Complete step by step answer:
Coordination compounds refer to the chemical entities that consist of an array of anions or neutral molecules that are bound to a central atom via coordinate covalent bonds. They are also known as coordination complexes. The neighbouring chemical particles that are bound to the central atom are referred to as ligands (also known as complexing agents). Platinum-containing complexes marked a milestone in drug discovery and revolutionized cancer treatment since the introduction of cisplatin. Initially invented in 1844 it was developed to treat testicular cancer and showed survival rates of more than ${\text{90\% }}$.
A platinum complex \[{\text{cis - [PtC}}{{\text{l}}_{\text{2}}}{{\text{(N}}{{\text{H}}_{\text{3}}}{\text{)}}_{\text{2}}}{\text{]}}\] known as cis−platin is used as an anticancer agent.

Hence, the correct option is option B.

Note:
The word ligand means to tie or bond. It performs the function to donate a pair of electrons to the central metal atom or ion to form a coordination complex. Ligands can be divided into a strong field and weak field ligands. The strong field ligands cause large splitting of crystal field energy and weak field ligands produce a small splitting. It is important to remember the spectrochemical series of ligands. The order according to their crystal field energy splitting can be written as:\[{I^ - }\; < \;B{r^ - }\; < \;{S^{2 - }}\; < \;SC{N^ - }\;\left( {S-bonded} \right){\text{ }} < \;C{l^ - }\; < \;N{O_3}^ - \; < \;{N_3}^ - \; < \;{F^ - }\; < \;O{H^ - }\; < \;{C_2}{O_4}^{2 - }\; < \;{H_2}O\; < \;NC{S^ - }\;\left( {N-bonded} \right)\]
\[{\text{ }} < \;C{H_3}CN\; < \;py\; < \;N{H_3}\; < \;en\; < \;2,2' - bipyridine\; < \;phen\; < \;N{O_2}^ - \; < \;PP{h_3}\; < \;C{N^ - }\; < \;CO.\]
Despite the benefits the platinum-based complexes suffer from severe side effects as well as intrinsic or acquired multidrug drug resistance (MDR), limiting its applications. To overcome these disadvantages research is being conducted on “rule-breaking” platinum compounds.