2. Answer ALL parts (a) (i) For each of the following metals, state: The most common oxidation states in aqueous solution The d or f electron count(s) of the most common oxidation states in aqueous solution The type of therapy or imaging modality the oxidized metal cation is used for in medicine Re; illin, Fe [9 marks] (ii) Place the following Pt(II) complexes in increasing order of rate of hydrolysis. Explain your reasoning. cis-[PtCl2(NH3)2], cis-[PtCl2(NH3)(3-Me-C5H4N)], cis-[PtCl2(NH3)(2-Me-C3H4N)] [3 marks] (b) The commercially available 99m Tc drug (compound 2, shown below) has been developed as a single-photon emission computed tomography (SPECT) imaging agent. + Mez CI Mez Pan... Me, CI Mez 2 Question 2 continued on next page Question 2 continued (i) State two key features of compound 2 that enable it to function as an effective imaging agent in vivo. [2 marks] (ii) Draw a synthetic scheme for 2 starting from 99m TcO4 to illustrate how this drug may synthesised. [4 marks] (iii) What is the chemical form of the 99m Tc complex 2 in the human body likely to be? Provide a reason for your answer. [2 marks] (c) Compound 3 (shown below) has been developed as a dual modal imaging agent: + Re ." OC 3 Question 2 continued on next page Question 2 continued (i) With reference to each of the metal centres in 3, describe the physical processes that give rise to the particular imaging capability of each part of the molecule. [4 marks] (ii) List all the possible types of electronic absorption transitions that can occur in the UV-visible region in a transition metal polypyridyl complex. [3 marks] (iii) State, with a brief explanation, where compound 3 is most likely to localise in human cells. [2 marks] (iv) Suggest, with explanations, two structural modifications to 3 that would make it a more effective imaging agent. [4 marks] [Total 33 marks] Question 3 on next page 2. Answer ALL parts (a) (i) For each of the following metals, state: The most common oxidation states in aqueous solution The d or f electron count(s) of the most common oxidation states in aqueous solution The type of therapy or imaging modality the oxidized metal cation is used for in medicine Re; illin, Fe [9 marks] (ii) Place the following Pt(II) complexes in increasing order of rate of hydrolysis. Explain your reasoning. cis-[PtCl2(NH3)2], cis-[PtCl2(NH3)(3-Me-C5H4N)], cis-[PtCl2(NH3)(2-Me-C3H4N)] [3 marks] (b) The commercially available 99m Tc drug (compound 2, shown below) has been developed as a single-photon emission computed tomography (SPECT) imaging agent. + Mez CI Mez Pan... Me, CI Mez 2 Question 2 continued on next page Question 2 continued (i) State two key features of compound 2 that enable it to function as an effective imaging agent in vivo. [2 marks] (ii) Draw a synthetic scheme for 2 starting from 99m TcO4 to illustrate how this drug may synthesised. [4 marks] (iii) What is the chemical form of the 99m Tc complex 2 in the human body likely to be? Provide a reason for your answer. [2 marks] (c) Compound 3 (shown below) has been developed as a dual modal imaging agent: + Re ." OC 3 Question 2 continued on next page Question 2 continued (i) With reference to each of the metal centres in 3, describe the physical processes that give rise to the particular imaging capability of each part of the molecule. [4 marks] (ii) List all the possible types of electronic absorption transitions that can occur in the UV-visible region in a transition metal polypyridyl complex. [3 marks] (iii) State, with a brief explanation, where compound 3 is most likely to localise in human cells. [2 marks] (iv) Suggest, with explanations, two structural modifications to 3 that would make it a more effective imaging agent. [4 marks] [Total 33 marks] Question 3 on next page
