An unknown plant sample is subjected to acidic hydrolysis and one of the water-soluble components found in the hydrolysate is fructose. Provide a Fischer projection structure for the open-chain form of fructose.
The following information is known about fructose:
i. Has a molecular formula of C6H12O6
ii. Exhibits mutarotation.
iii. Unreactive with Br2/H2O.
iv. Reduces Fehling's solution to give D-gluconic acid and D-mannonic acid.