JEE MainChemistryBiomolecules
An unknown carbohydrate 'C' with the molecular formula C ₁₂ H ₂₂ O ₁₁ does not exhibit mutarotation. On hydrolysis with the enzyme invertase, it gives a mixture which is overall laevorotatory. Identify the INCORRECT statement regarding the two monosaccharide components, 'M' and 'N', present in this mixture.
Options
- AM and N are epimers of each other.
- BM and N yield the same osazone upon reaction with excess phenylhydrazine.
- COne of them is oxidised by bromine water while the other is not.
- DBoth M and N undergo mutarotation in aqueous solution.
Correct answer
A. M and N are epimers of each other.
Step-by-step solution
The carbohydrate 'C' is sucrose, as it is a non-reducing sugar (does not exhibit mutarotation) and its hydrolysis produces invert sugar, which is a laevorotatory mixture of D-glucose and D-fructose. Let 'M' and 'N' be glucose and fructose. Glucose is an aldohexose and fructose is a ketohexose. They are functional isomers, not epimers. Epimers are diastereomers that differ in configuration at only one specific chiral center (e.g., glucose and mannose). Therefore, the statement that they are epimers is incorrect. Glu