Question

Identify a medicinal compound having amide linkage.

• A. Aspirin
• B. Methylsalicylate
• C. Curcumin
• D. Paracetamol

Hint:

Look for "aceta" or "mide" in the chemical names! Paracetamol is chemically known as Acetaminophen, an abbreviation of para-acetylaminophenol. The acetyl-amino part forms the amide link.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
We must identify which common medicinal drug from the given list contains an amide functional group linkage ($-\text{CONH}-$) within its chemical structure.

Step 2: Detailed Explanation:
Let's analyze the molecular structure and functional groups of each given medicinal compound:
(a) Aspirin (Acetylsalicylic acid): Made by reacting salicylic acid with acetic anhydride. It contains a carboxylic acid group ($-\text{COOH}$) and an ester linkage ($-\text{O-CO-CH}_3$). It does not contain an amide.
(b) Methyl salicylate (Oil of Wintergreen): Made by reacting salicylic acid with methanol. It contains a phenolic hydroxyl group ($-\text{OH}$) and an ester linkage ($-\text{COOCH}_3$). It does not contain an amide.
(c) Curcumin: The active ingredient in turmeric. It is a diarylheptanoid containing phenolic groups and ether linkages, but it entirely lacks any nitrogen atoms. Thus, it cannot have an amide.
(d) Paracetamol (Acetaminophen): Its IUPAC name is N-acetyl-p-aminophenol. It is synthesized by acetylating p-aminophenol. Its structure consists of a benzene ring attached to a hydroxyl group at one end, and an acetylated amine group at the para position. The acetylated amine group is $\text{CH}_3\text{-CO-NH-C}_6\text{H}_4\text{-OH}$. The $-\text{CO-NH}-$ bond bridging the acetyl group to the aromatic ring is a classic amide linkage.

Step 3: Final Answer:
Paracetamol has an amide linkage, matching option (d).