To provide comprehensive coverage against

potential atypical pathogens, IV Azithromycin was added to the patient’s

regimen. Azithromycin is a semi-synthetic macrolide derived from the naturally

occurring erythromycin. What specific chemical alteration is made to the

macroscopic lactone ring of erythromycin to create azithromycin, and how does

this modification clinically benefit a patient requiring prolonged tissue concentrations?