A-LevelChemistryIntroduction to organic chemistry9701/42 · May/June 2023 · Q68 Marks

Perindopril is a drug used to treat heart disease. [Figure 6.1, structure of perindopril]

(a)(i)State the number of chiral carbon atoms present in one molecule of perindopril.[1]
(a)(ii)Suggest one benefit and one disadvantage of producing a drug such as perindopril as a single pure optical isomer. benefit disadvantage[2]
(b)(i)Name all the functional groups in perindopril.[2]
(b)(ii)A sample of perindopril is hydrolysed with hot aqueous acid. Draw the structures of the three organic products of the complete acid hydrolysis of perindopril.[3]

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Mark scheme

Marking points from the official mark scheme (May/June 2023). The mark or mark type is shown in brackets.

[1] 5/five
[1] M1 benefit: higher biological efficiency / activity (of the drug) OR less side effects OR smaller dose required (as drug more potent)
[1] M2 disadvantage: the need to separate (a racemic mixture into a single stereoisomer) OR lower yield (of biologically active molecule/product) OR need a chiral catalyst / enzyme (in the synthesis so expensive)
[1] carboxylic acid/carboxyl
[1] ester
[1] amide
[1] amine
[1] Structure of ethanol (CH3CH2OH)
[1] Structure of 2-amino-1,5-pentanedioic acid (HOOC-CH2CH2CH(NH2)COOH)
[1] Structure of (2S,3aS,7aS)-1-(2-carboxyethyl)octahydro-1H-indole-2-carboxylic acid (a bicyclic carboxylic acid with a secondary amine and another carboxylic acid group)

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