3-aminobenzoic acid can be synthesised from methylbenzene in three steps. [Figure showing reaction scheme from methylbenzene to M (step 1), M to N (step 2), N to 3-aminobenzoic acid (step 3). Structure of 3-aminobenzoic acid is given.] Draw the structures of M and N in the boxes.

1. (a)(i)3-aminobenzoic acid can be synthesised from methylbenzene in three steps. [Figure showing reaction scheme from methylbenzene to M (step 1), M to N (step 2), N to 3-aminobenzoic acid (step 3). Structure of 3-aminobenzoic acid is given.] Draw the structures of M and N in the boxes.[2]
2. (a)(ii)Suggest reagents and conditions for each step of the synthesis. step 1 step 2 step 3[3]
3. (b)(i)A mixture of serine, HOCH₂CH(NH₂)CO₂H, and lysine, H₂N(CH₂)₄CH(NH₂)CO₂H, reacts to form several different products. Draw the structures of the two structural isomers with the molecular formula C₆H₁₂N₂O₅ that could be present in the product mixture. The functional group formed in each case should be displayed.[3]
4. (b)(ii)Predict the number of different structural isomers with the molecular formula C₉H₁₉N₃O₄ that could be present in the product mixture. molecular formula | number of structural isomers formed ------------------|----------------------------------- C₉H₁₉N₃O₄ |[1]
5. (c)(i)Glutathione is a naturally occurring compound found in plants. [Figure showing glutathione structure] On the diagram of glutathione, label each chiral centre with an asterisk (*).[1]
6. (c)(ii)Draw the structures of the three products formed after complete acid hydrolysis of glutathione. Assume the thiol group, –SH, does not react.[2]
7. (c)(iii)Glutathione is soluble in water. By referring to the structure of glutathione, explain why glutathione is soluble in water.[1]

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