Question

Pyranose ring structure of glucose is due to hemiacetal formation between:

• A. C${}_1$and C${}_5$
• B. C${}_1$and C${}_4$
• C. C${}_1$and C${}_3$
• D. C${}_2$and C${}_4$

Answer 1

The correct option is A C${}_1$and C${}_5$

Pyranose ring structure of glucose is due to hemiacetal formation between C${}_1$ and C${}_5$ carbon atoms. In general, a pyranose is any cyclic isomer that has a five carbon atoms and one oxygen atom in a ring of six atoms. If a hydroxyl at the 5 position of an aldohexose, such as glucose, forms a hemiacetal with the aldehyde (position 1), the resulting isomer is glucopyranose.