Explanation:

D-glucopyranose is a monosaccharide with the molecular formula C6H12O6. It exists in two different forms: α-D-glucopyranose and β-D-glucopyranose. These two forms differ in the orientation of the hydroxyl group attached to the anomeric carbon atom (C1).

Anomers:
Anomers are a type of stereoisomers that are formed when a cyclic sugar molecule undergoes mutarotation. In the case of D-glucopyranose, the cyclic form is formed by the reaction between the aldehyde group (C1) and the hydroxyl group (C5) within the same molecule. The resulting cyclic form can exist in two different orientations: α or β. These two forms are called anomers of each other.

Differences between α and β anomers:
The α-anomer has the hydroxyl group attached to the anomeric carbon atom (C1) in the opposite direction to the CH2OH group at C5. In contrast, the β-anomer has the hydroxyl group attached to the anomeric carbon atom in the same direction as the CH2OH group at C5. This difference in orientation gives rise to different spatial arrangements of the atoms in the molecule.

Epimers:
Epimers are a type of diastereomers that differ in the configuration of only one stereogenic center. In the case of D-glucopyranose, the α-anomer and the β-anomer are epimers of each other because they differ in the configuration of the hydroxyl group at the anomeric carbon atom (C1).

Diastereomers:
Diastereomers are stereoisomers that are not mirror images of each other and have different physical properties. In the case of D-glucopyranose, the α-anomer and the β-anomer are also diastereomers of each other because they have different physical properties such as melting point, boiling point, and solubility.

Conclusion:
In summary, the two forms of D-glucopyranose, α-D-glucopyranose and β-D-glucopyranose, are called anomers because they differ in the orientation of the hydroxyl group at the anomeric carbon atom. They are also epimers because they differ in the configuration of only one stereogenic center. They are not enantiomers because enantiomers are mirror images of each other, which is not the case for α and β-D-glucopyranose.