Questions from Organic Chemistry

Q: Draw the more stable chair conformation for each of the following compounds

Draw the more stable chair conformation for each of the following compounds: a. β-D-Galactopyranose b. α-D-Glucopyranose c. β-D-Glucopyranose

Q: Draw the open-chain form of the following cyclic monosaccharide:

Draw the open-chain form of the following cyclic monosaccharide:

Q: There are two chair conformations for β-D-glucopyranose.

There are two chair conformations for β-D-glucopyranose. Draw the less stable chair conformation.

Q: Consider the structures of the following two D-aldotetroses:

Consider the structures of the following two D-aldotetroses: Each of these compounds exists as a furanose ring, which is formed when the OH at C4 attacks the aldehyde group. Draw each of the followin...

Q: Draw a mechanism for the acid-catalyzed cyclization of l-

Draw a mechanism for the acid-catalyzed cyclization of l-threose to give β-L-threofuranose. (Hint: You may want to first review the mechanism for acid-catalyzed hemiacetal formation, Mechanism 19.5.)...

Q: Draw a mechanism for the acid-catalyzed cyclization of d-

Draw a mechanism for the acid-catalyzed cyclization of d-fructose to give β-D-fructofuranose.

Q: Draw the open-chain form of the carbohydrate that can undergo

Draw the open-chain form of the carbohydrate that can undergo acid-catalyzed cyclization to produce α-D-fructopyranose.

Q: Draw the product obtained when each of the following compounds is treated

Draw the product obtained when each of the following compounds is treated with acetic anhydride in the presence of pyridine: a. α-D-Galactopyranose b. α-D-Glucopyranose c. β-D-Galactopyranose

Q: Draw the product obtained when each of the compounds from the previous

Draw the product obtained when each of the compounds from the previous problem is treated with methyl iodide in the presence of silver oxide (Ag2O).

Q: When α-D-galactopyranose is treated with ethanol in the

When α-D-galactopyranose is treated with ethanol in the presence of an acid catalyst, such as HCl, two products are formed. Draw both products and account for their formation with a mechanism