Labetalol, a β‑blocker antagonist of epinephrine and norepinephrine, is commonly used in treating high blood pressure. Labetalol can be synthesized from a primary amine and an epoxide. Using the starting materials given, identify the curved arrows to complete the mechanism for the synthesis of Labetalol. The general base (:B) will be used for proton transfers. Step 1: Identify the curved arrows for the first step.