This question involves identifying the type of carbohydrate based on its structure. The structure shown is a six-membered ring with oxygen, indicating a pyranose form. The anomeric carbon (the carbon attached to two oxygen atoms in the ring) has the hydroxyl group pointing downward, which is characteristic of an α-anomer. The ring is formed from a hexose sugar, and since it is a cyclic form, it is derived from an aldohexose (as ketohexoses typically form furanose rings). Therefore, the correct identification is an α-pyranose.

Step-by-step reasoning:

Step 1: Observe the ring size. The ring has six atoms (five carbons and one oxygen), which is a pyranose ring.

Step 2: Check the anomeric carbon. The carbon at the right side of the oxygen in the ring has the OH group pointing downward. In Haworth projections, a downward OH on the anomeric carbon indicates the α-anomer.

Step 3: Determine the parent sugar. The ring has multiple CH₂OH groups, typical of hexoses. Since it is a pyranose, it is derived from an aldohexose (like glucose), not a ketohexose (like fructose, which usually forms furanose).

Final answer: It is an α-pyranose.

Related Topics

Carbohydrates: Carbohydrates are polyhydroxy aldehydes or ketones. They are classified based on their functional groups (aldose or ketose) and the number of carbons (e.g., hexose for 6 carbons). Cyclic forms are common for sugars, where the carbonyl group reacts with an OH to form a hemiacetal or hemiketal, resulting in pyranose (6-membered) or furanose (5-membered) rings. The anomeric carbon (the carbonyl carbon in the open chain) can have α or β configuration based on the orientation of the OH group relative to the ring.

Formulae

No specific formulae are required for this identification, but understanding the Haworth projection and anomeric configuration is key. The general formula for a hexose is C₆H₁₂O₆.