Summary

Macrocycles are molecules with a ringed architecture =12 atoms. They are flexible and have very good binding activity to their site of activity. Their functional groups can interact across a wide range of binding sites without losing activity or being pushed off. They are very potent and very selective. Many have good solubility, lipophilicity, metabolic stability, and bioavailability. However, some, such as fidaxomicin and rifaximin, are not very well absorbed. This article discusses the emerging macrocycles and their mode of action.