JEE Main 2022 · 29 June · morning · Single correct · +4 / −1
Which of the following compound does not contain sulphur atom?
- (a) Cimetidine
- (b) Ranitidine
- (c) Histamine
- (d) Saccharin
Answer and solution
Answer (c) Histamine
Solution
Chemistry ma’am · 3 steps
The antacids were built from histamine by adding a sulphur chain, so histamine itself has none.
- Start with histamine. Histamine is an imidazole ring joined to an ethylamine chain, C₅H₉N₃. It contains only carbon, hydrogen and nitrogen.
- The antacids. Cimetidine and ranitidine block the histamine receptors in the stomach. Chemists designed them by lengthening histamine's side chain, and that longer chain carries a thioether link, -CH₂-S-CH₂⁻.
Compound Formula Where sulphur sits Cimetidine C₁₀H₁₆N₆S thioether in the side chain Ranitidine C₁₃H₂₂N₄O₃S thioether in the side chain Histamine C₅H₉N₃ no sulphur Saccharin C₇H₅NO₃S SO₂ group in the five-membered ring - So. Three of the four contain sulphur. Only histamine has none, so the answer is (c).
The idea to keep. Histamine is the parent molecule. The antihistamine antacids cimetidine and ranitidine add a sulphur-containing chain to it, and saccharin carries an SO₂ group in its ring.
Answer from the NTA final answer key. Solution by PrepWiser.