Penicillin, a widely used antibiotic, was first discovered in 1928. Over time, some bacteria have developed resistance to penicillin by producing an enzyme that breaks down the beta-lactam ring in its structure. To counter this resistance, chemists modified the penicillin structure to create methicillin, which is resistant to the bacterial enzyme.
(i) Encircle the ether group in methicillin.
(ii) Determine the amide group in methicillin and the type of amide it has.