JEE Main 2026 · 5 April · evening · Single correct · +4 / −1
Given below are two statements:
Statement I:
and
are two anomers of D-(+)-glucode.
Statement II : The open chain forms of D-glucose and D- fructose contain three similar chiral carbons at C₃,C₄ and C₅.
In the light of the above statements, choose the correct answer from the options given below :
- (a) Both Statement I and Statement II are true
- (b) Both Statement I and Statement II are false
- (c) Statement I is true but Statement II is false
- (d) Statement I is false but Statement II is true
Answer and solution
Answer (a) Both Statement I and Statement II are true
Solution
Chemistry ma’am · 4 steps
Check the rings carbon by carbon: if only C1 differs, they are anomers. Then line up the two Fischer chains.
- Compare the rings. Both structures have the same groups at C2 (OH down), C3 (OH up), C4 (OH down) and C5 (CH₂OH up). That is the pattern of D-glucopyranose.
- Only C1 differs. In the first ring the C1 OH points down, opposite to CH₂OH, so it is α-D-glucose. In the second it points up, on the same side as CH₂OH, so it is β-D-glucose. Isomers that differ only at the hemiacetal carbon C1 are anomers, so Statement I is true.
Carbon Open-chain D-glucose Open-chain D-fructose C2 chiral, OH on right C=O, not chiral C3 chiral, OH on left chiral, OH on left C4 chiral, OH on right chiral, OH on right C5 chiral, OH on right chiral, OH on right - Statement II. C3, C4 and C5 are chiral in both sugars and have the same configuration. The two differ only at C1 and C2, where glucose has CHO and a chiral C2 while fructose has CH₂OH and a keto C2. So Statement II is true.
- So. Both statements are true, which is option (a).
The idea to keep. Anomers differ only at C1, so check that every other ring carbon matches. Glucose and fructose share the same configuration at C3, C4 and C5, which is why they give the same osazone.
Answer from the NTA final answer key. Solution by PrepWiser.