Question

In the following disaccharide,

• A. Ring [A] is pyranone with $ \alpha - $ glycosidic link
• B. Ring [A] is furanose with $ \alpha - $ glycosidic link
• C. Ring [B] is pyranose with $ \beta - $ glycosidic link
• D. Ring [B] is furanose with $ \alpha - $ glycosidic link

Answer 1

Answer: (A)

The ring $A$ is pyranone. In $\alpha -$ type glycosidic linkage, the hydroxyl group $(OH)$ nearer the oxygen atom of ring is written on lower side, whereas in $\beta -$ type it is written on upper side.