The following compound has been found to be an inhibitor of penicillinase. The enzyme can be reactivated by hydroxylamine (NH₂OH). Propose a mechanism to account for the reactivation.

Draw the products of the following reactions:

d.

Propose a mechanism for the rearrangement of the thiazoline obtained from the reaction of Edman's reagent with a peptide to a PTH-amino acid. (Hint: Thioesters are very reactive toward nucleophiles.)

Co²⁺ catalyzes the hydrolysis of the lactam shown here. Propose a mechanism for the metal-ion catalyzed reaction.

The following compound has been found to be an inhibitor of penicillinase. The enzyme can be reactivated by hydroxylamine (NH₂OH). Propose a mechanism to account for the inhibition.

A Mannich reaction puts a -group on the α-carbon of a ketone. Propose a mechanism for the reaction.

In condensation reactions, which of the following best describes what typically occurs?

Which of the following transformations is an example of a condensation reaction?