FPGEE Pharmaceutical Chemistry 2 — Questions and Answers
Question 1: Which functional group is responsible for the acidic properties of aspirin?
- Ester group
- Carboxylic acid group (Correct answer)
- Hydroxyl group
- Amide group
Correct answer: Carboxylic acid group
The carboxylic acid (-COOH) group in aspirin (acetylsalicylic acid) donates a proton, conferring its acidic properties.
Question 2: The term 'prodrug' refers to a compound that:
- Is active as administered
- Requires metabolic conversion to exert its effect (Correct answer)
- Is excreted unchanged in urine
- Binds irreversibly to its receptor
Correct answer: Requires metabolic conversion to exert its effect
A prodrug is pharmacologically inactive until metabolized in the body to its active form.
Question 3: Which bond type is hydrolyzed during the metabolism of ester prodrugs?
- Amide bond
- Ether bond
- Ester bond (Correct answer)
- Disulfide bond
Correct answer: Ester bond
Esterases in plasma and tissues cleave the ester bond, releasing the active drug from an ester prodrug.
Question 4: The Henderson-Hasselbalch equation is used primarily to predict:
- Drug solubility in organic solvents
- The degree of ionization of a drug at a given pH (Correct answer)
- The melting point of a pharmaceutical compound
- The rate of oxidative metabolism
Correct answer: The degree of ionization of a drug at a given pH
The Henderson-Hasselbalch equation relates pH, pKa, and the ratio of ionized to unionized drug forms.
Question 5: Which class of reaction is CYP3A4-mediated hydroxylation classified as?
- Phase II conjugation
- Phase I oxidation (Correct answer)
- Phase I reduction
- Phase II acetylation
Correct answer: Phase I oxidation
CYP3A4 is a cytochrome P450 enzyme that catalyzes Phase I oxidation reactions, including aromatic and aliphatic hydroxylation.
Question 6: Isomerism involving non-superimposable mirror images of a molecule is called:
- Geometric isomerism
- Constitutional isomerism
- Enantiomerism (Correct answer)
- Conformational isomerism
Correct answer: Enantiomerism
Enantiomers are non-superimposable mirror images of each other, differing in the spatial arrangement around a chiral center.
Question 7: Which property of a drug is most directly improved by salt formation?
- Lipophilicity
- Aqueous solubility (Correct answer)
- Protein binding
- Blood-brain barrier penetration
Correct answer: Aqueous solubility
Salt formation converts a poorly water-soluble drug into an ionized form that typically has significantly greater aqueous solubility.
FPGEE Pharmaceutical Chemistry 2
Which functional group is responsible for the acidic properties of aspirin?