The structure given below is known as

Penicillin G is an antibiotic used to treat a number of bacterial infections. This includes pneumonia, strep throat, syphilis, cellulitis, tetanus.etc.

Penicillin G has a narrow spectrum. Those effective mainly against Gram-positive or Gram-negative bacteria are narrow-spectrum antibiotics.

 The functional groups are:

• at 1, a thioether
• at 4,7,8, an amide
• at 11,12,13, a carboxylate ion
• at 14,15, an amide

The 5-membered ring is called a thiazolidine ring.

An amide that is part of a 4-membered ring is called a β-lactam.