Question

Morphine is the structure chiefly responsible for the biological activity of opium. What is the name given to the chemical that is chiefly responsible for the biological activity of a natural extract?

• A. Lead compound
• B. Pharmacophore
• C. Active principle
• D. Lead principle

Answer 1

The Correct Option is C

Step 1: Understanding Active Principles - The active principle of a natural extract is the bioactive chemical that is responsible for its pharmacological effects. - For example, morphine is the active principle of opium, and quinine is the active principle of cinchona bark.


Step 2: Evaluating the Options - (A) Lead compound → Incorrect. A lead compound is a synthetic or natural molecule with potential therapeutic effects, but it is not necessarily the main bioactive substance of a natural extract.
- (B) Pharmacophore → Incorrect. A pharmacophore is a structural feature within a molecule that is responsible for its biological activity but is not a specific bioactive compound itself.
- (C) Active principle → Correct. The active principle is the chief biologically active component in a natural product that gives it medicinal properties.
- (D) Lead principle → Incorrect. This is not a standard term in pharmacognosy or medicinal chemistry.


Step 3: Selecting the Correct Answer - The correct term for the biologically active component of a natural extract is active principle, making option (C) the correct choice.