CNS Active Agents (Sedatives & Antiepileptics) | Medicinal Chemistry | GPAT Mock Test

Welcome to the GPAT Mock Test on CNS Active Agents, a crucial topic in Medicinal Chemistry. This quiz is specifically designed for B.Pharma graduates preparing for the GPAT exam. It covers essential subtopics including sedative-hypnotics, antiepileptic agents, neuroleptics, and anti-anxiety drugs. You will face 25 multiple-choice questions that test your knowledge of drug classification, structure-activity relationships (SAR), mechanisms of action, and key chemical properties. After submitting your answers, you will receive your score instantly, with correct and incorrect answers highlighted for your review. To aid your preparation, you can also download a PDF file containing all the questions and their correct answers. Take this test to evaluate your understanding and identify areas for improvement. Best of luck!

1. The substitution at C5 position of barbituric acid is essential for its hypnotic activity. Which of the following statements about C5 substitution is TRUE?

2. Which position of the benzodiazepine ring is critical for anxiolytic activity, and substitution with an electron-withdrawing group like Cl or NO2 enhances it?

3. Phenytoin, a hydantoin derivative, primarily exerts its anticonvulsant effect by:

4. In the Structure-Activity Relationship (SAR) of phenothiazine antipsychotics, which position on the phenothiazine nucleus requires an electron-withdrawing substituent for optimal activity?

5. Buspirone is an anxiolytic agent that differs from benzodiazepines in its mechanism of action. What is its primary mechanism?

6. Zolpidem, a non-benzodiazepine hypnotic, selectively binds to which subunit of the GABA-A receptor?

7. Ethosuximide is the drug of choice for treating absence (petit mal) seizures. Its mechanism of action involves the blockage of:

8. Haloperidol belongs to which class of antipsychotic drugs and is characterized by a C4-tertiary amino propiophenone chain?

9. Which of the following benzodiazepines is an ultra-short-acting agent often used for inducing anesthesia, with a triazolo ring fused at the 1,2-position?

10. The metabolism of Diazepam produces active metabolites. Which of the following is an active metabolite of Diazepam?

11. Valproic acid is a broad-spectrum antiepileptic drug. Which of the following is NOT a proposed mechanism of action for Valproic acid?

12. Clozapine is an atypical antipsychotic known for its efficacy in treatment-resistant schizophrenia. What is a major life-threatening adverse effect associated with it?

13. Flumazenil is a specific antagonist used to reverse the sedative effects of benzodiazepines. It acts by:

14. Carbamazepine, used for treating partial and tonic-clonic seizures, is chemically classified as a:

15. In the SAR of butyrophenone antipsychotics like Haloperidol, what is the optimal length of the alkane chain connecting the ketone group and the tertiary amine?

16. For benzodiazepines, a phenyl group at position 5 is optimal for activity. What happens if this phenyl group is replaced with a cyclohexyl group?

17. The duration of action of barbiturates is primarily determined by their lipid solubility. Which of the following is an ultra-short-acting barbiturate with high lipid solubility?

18. Lamotrigine is a newer antiepileptic drug effective against a broad range of seizures. Its primary mechanism of action involves:

19. Thioxanthenes like Thiothixene are structurally similar to phenothiazines. What is the key structural difference?

20. Meprobamate, an older anxiolytic and sedative, belongs to which chemical class?

21. In the structure of Benzodiazepines, the presence of a carbonyl group at position 2 is important for activity. Replacing this carbonyl with a thiocarbonyl group generally:

22. Gabapentin was designed as a GABA agonist, but its primary antiepileptic mechanism is now understood to be:

23. Risperidone is an atypical antipsychotic that shows high affinity for which two receptor types, contributing to its efficacy and side-effect profile?

24. Propranolol is sometimes used to manage performance anxiety. Its anxiolytic effect is primarily due to:

25. Topiramate is a newer antiepileptic drug with multiple mechanisms of action. Which of the following is NOT a recognized mechanism of Topiramate?