Tetraisopropyldisiloxanyl, or TIPDS, is an important protective group created specifically for polyhydroxy substances like sugar. TIPDS can shield two alcohol groups of a molecule:

a. The isopropyl groups around the Si atoms hinder the TIPDS group slightly. Which —OH of 1-methoxy-α-D-arabinofuranose has a higher chance of reacting with TIPDS chlorine first? Draw the product with one oxygen attached to the TIPDS group.

b. Once the TIPDS group has been connected to the first oxygen, the next oxygen nearest to it is reached. Draw the final product with TIPDS attached to two oxygens.

c. Now that the oxygens are shielded, the unprotected hydroxy group can undergo a reaction. Draw the final product formed when treating the protected 1-methoxy-α-D-arabinofuranose from (b) with tosyl chloride, pyridine, and NaBr.