Chapter 18, Problem 22P

(a)

Interpretation Introduction

Interpretation: The $\beta$ -lactam portion of amoxicillin and cephalexin is to be identified.

Concept Introduction:The cyclic amides are known as lactums. The four membered ring containing amide group is known as $\beta$ -lactam. Amoxicillin is a type of penicillin. The common feature in all penicillin is the $\beta$ -lactam ring is bonded to the five-membered ring containing sulfur atom. Cephalexin is known to be an effective $\beta$ -lactam antibiotic.

(b)

Interpretation Introduction

Interpretation: The structural formula of the molecule which is formed by the enzyme catalyzed hydrolysis of the $\beta$ -lactam ring of penicillin G is to be drawn.

Concept Introduction:The cyclic amides are known as lactums. The four membered ring containing amide group is known as $\beta$ -lactam. Due to the presence of $\beta$ -lactam ring the penicillin G shows antibacterial activity.